B17A1 Build plans: help (thoughts, opinions) needed

ASSISTANCE Hybrids & Advanced Aftermarket Engine Performance
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Guys, I think I mentioned it but I fragged the head on my new (to me) 92 GS-R being irresponsible in some way while replacing the cam seals, so I’m going to accelerate my plans and go ahead and do a build now. I’m effectively just trying to make a strong daily driver with the same basic powerband as stock, but just a little more peppy. I am not looking for big high end HP numbers and I’m not looking for a tempermental beast.

Here are my plans. I need help and opinions on everything. I already have a replacement head but I’m not sure if I’m going to go with it or the Endyn DHPS “cleaned up” head.

If I don’t mention something specifically, just assume I’m using stock parts.

Stage 1:

Bottom end:
Flatten deck at local machine shop (don’t know the proper term)
hone cylinders
P30 pistons - skirts coated by swaintech
Balance rotating assembly I need a recomendation on where to send my crank/rods/pistons!
Shot peen stock rods
ARP hardware everywhere, OEM gaskets & bearings

Head:
Either the DHPS head as is or the used B17 head I bought with the valve job/clean inspect by Portflow.
Portflow is still considered a good company, right?
Type R Intake valves?? I’m not sure if these are worth the $150…
I’ve convinced myself the Toda valve springs are worth the extra cost.
Crower Cromoly retainers (I don’t buy into the whole TI bandwagon)

Other (already have this stuff):
K&N drop-in filter
Comptech 4-2-1 one piece Headers

Stage 2 Plans:
After everything above is all happy and running well and any other maintenance items are taken care of like replacing all the bushings in the suspension and replacing all the coolant lines, etc.

Skunk2 Pro I cams. I talked at length with a great guy (Mike) at KingMotorsports and he convinced me these would work well with my performance and reliability goals and, while more compression would of course be better, that they would be fine with an ~11:1 static CR. He said they make power pretty much everywhere over stock from 2k up to about 8.2k and that they wouldn’t really make power for me above that. A coworker has been running them for 85k miles and his rocker arms still don’t show excessive wear. Sounds good to me!

Skunk2 Pro Cam gears. These look like decent enough gears and I haven’t seen any complaints about them…I don’t really care what gears I use as long as they stay where I put them.

EMS: Some kind of good, proven, reliable Engine Managment System that doesn’t have any serious bugs and still has ongoing support. I need to find a good tuner in the Illinois/Indiana/Ohio/Kentucky area and will go with what they prefer. Probably Hondata S300, but the new AEM Series 2 EMS Plug N Play also looks pretty nice.

I’ll do the base tune with a wideband and accelerometer and then get it ironed out at a dyno.

Anyone know any good tuners in the area?

That pretty much covers everything for the next 6 months or so. Do you guys see anything glaringly out of place in this? Any and all comments and advice are welcome. There are suspension plans during this time too, but I thought this wasn’t the place to discuss them.

One last thing: how long has the most recent version of the RS*R exhaust been out of production. I thought they had just started making it again, but then realized that was back in like 2005! Man, where does the time go?

Anyway, does anywhere still have them new?

EDIT: current build plans at bottom of page 5

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For the most part things seem to be on the up and up, imo… I’ll just run down the list kinda as you typed it out and give my 2 cents.

Resurfacing the block is of course a given. You can ‘deck’ it and take more material off to raise compression, but I would take as little off as possible… just make it straight/level and call it good.

Honing the cylinders, again, is a given. But I would have them go to 81.5MM (20 thousandths over-bore). It makes absolutely sure that your cylinders are not out of round… on an engine that is 17years+ old, I’m sure the cylinder walls arent perfectly round anymore. Use the stock 81mm headgasket, it allows for the .5mm overbore.

As far as balancing, I can’t name a place for you as I’m not local to your area… but the same place that does the block should be able to do the internals as well, or at least refer you to someone. On that note, it would be nice if you know of a place that works on Honda motors regularly, just to be on the safe side.

The head… Well, I believe PortFlow to still be a reputable company with good work, so if they checked out the B17 head you have and they say its good, I would run that. Save the money and get a good intake manifold and maybe a bigger throttle body. On that link you provided, it states that Endyn has recalled his LMAs due to coil bind, the rocker arms are being re-designed, etc etc… That makes me weary and glad that my bro bought the honda coil-type LMA rather than waiting for the Endyn ones. I’m not knocking them, Endyn is a smart dude, but I like OEM stuff personally.

Type-R valves? Eh… I wouldn’t bother. Stock B16 valves are good to 600+whp, and the weight savings isn’t worth it imo.

As far as springs… I can’t really say much here. I’ve never had any experience with Toda stuff… My brother is running Skunk2 Pro Titanium retainers and dual springs with their cams, etc… but as you were getting at, Titanium stuff is going to wear down quicker so it may require replacement sooner than later. But if you’re going to buy Skunk cams, why not go with their springs? Just curious.

Cams… I’m kind of weary when it comes to this. Pro1s will probably do the trick. Though the more overlap the cams have, the less functional-compression your motor will have… so take that into account when choosing cams.

I do like Skunk Pro cam gears… my brother and I both use them. 6-bolts? Yes please. But once you get your cams degree’d in and everything… make sure to use thread-sealer and torque the bolts down to 8ft/lbs (as per Skunk2). Dont want those suckers vibrating out on you.

Engine management… Just make sure whoever you go with is a reputable place that has the cars to back up their product. Tuning is very key to any build. If you can find a Neptune dealer, i recommend that simply due to price and functionality… it can do a lot of stuff that Hondata can do. But as i said, whichever software you use, just make sure the tuner is experienced and can be vouched for.

The RS*R? On their website it’s no longer offered… You might get lucky scouring the web and calling dealers that still advertise them… Makes me realize how rare they are becoming.

Sorry for rambling along, I’m bored and since no one gave their 2cents… figured I’d just say mine.

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No need to appologize for rambling, I appreciate the input.

I was originally thinking that there weren’t any reputable engine builders in the area and was thinking I’d have to send stuff out to get balanced (I trust the local machine shop for flatening surfaces, but not much else) but I think I may have found a place in Indy who can take care of everything. I’ll call them on Monday and try to get a vibe off of them.

I may end up going .25 over, but if the cylinders are round, I don’t see a need to. I want to make sure I can bore it later if I need to and still use OEM cast pistons. The block only has 118k miles on it, so maybe I’ll get lucky and it won’t need it.

If I went with the Endyn head, I would not get any of their internals. The LMAs they are using now are just the Prelude/NSX ones with a machined shim added (I believe). The spring and surface is supposed to be the same as the Integra ones. But yeah, if the spring isn’t a Honda part, I’ll just pay the extra $5 ea for the B-series ones. I would use the rocker arms that are in the B17 head that is on the car and would sell the used B17 head that I bought.

The used head that I already purchased cost me $350 and I could probably sell it for the same price (although I’ll be out some shipping). Basic headwork from portflow would be an additional $350 plus shipping both ways (I must have explained poorly, the head hasn’t been checked out yet), but the ‘cleaned up’ Endyn DHPS head is $700, has new valve guides and was designed for better flow over a stock B17… So I’d actually save a little money if I went with the DHPS head. I went ahead and picked up a used set of B16 valves off ebay for $10 in case the ones in my old B17 head are bent or otherwise damaged. I can reuse my old keepers, valve seats are super cheap and the rest of the parts are going to be replaced anyway.

I’m actually a little concerned that the seat pressures on the Pro Series springs might be a little high considering they are also made for the Pro 3s that have a 13mm lift. You are right though, I should look into it a little more before blindly shelling out $90 more for the Todas. I do like that the Todas are progressively wound though, so I can get a normal seat pressure but still be able to handle the lift on those Skunk2s.

You said you were weary about cams. What do you mean exactly? I’m a little concerned about the Pro 1s myself. I had been looking at much milder cams like the Buddy Club III+, the Spoon Sports cams, Skunk2 Tuner Stage 1, etc. that could almost be used with ITR springs. I haven’t reallly researched the Pro 1s, so I need to look into them and see what the deal really is. Just because Mike was really nice and helpful doesn’t necessarily mean those are the prefect cams for my application.

As you say, I need to find a good, reputable tuner before I make any firm decisions about what EMS to use.

Thanks for the thoughts on everything and the heads up on the cam gears.

Hopefully some other folks will chime in their thoughts about the DHPS head option and the cams…

Robin

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As far as the cams, what I meant was the same thing you’re talking about… too big of a cam for the amount (or lack of) compression your block has. We just built a B16, 81.5mm bore, the dome on the piston was very close to a Civic Type-R piston… flat faced valves… prettymuch everything you could do to the B16 to get maximum compression, without boring it out.

At first we were going to go with the Skunk2 Pro2 cams, as the builder told us that the piston/valve combo would net 12.3-12.5:1 compression. Long story short, with the huge pistons and overbore, the motor was barely getting 11.1:1 or so. Taking that into consideration, we opted for the Tuner 2s.

After getting the car on the dyno, it ended up making 197whp… But the primary lobes on the cams are so big, that the vtec crossover had to be placed at 7,000rpm. It feels like the cam is too big. I believe a Tuner1 would suite his motor better.

On your setup, a Tuner1 might be on the big side, but still worth getting. I put '01 Type-R cams into my lsvtec and love the feel of them… But a little more aggressive might be an advantage.

On your setup, I wouldn’t go bigger than a Tuner1, max. But thats me.

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That build looks good. I pretty much agree w/ all of what United said.

I’m not really a fan of Skunk2, but my tuner also said GREAT things about the cams they’re making now. He pretty much wouldn’t recommend anything else. The cams I got (CTR) came w/ some skunk2 cam gears on them and one was sized onto the cam pretty bad. It obviously could just have been an install problem, but who knows. It was also an older cam gear, so I can’t put blame purely on Skunk2. But regardless, it made me very uneasy.

Toda was my choice for cam gears, never had any issues w/ them and had many friends using them for years and years with no issues. Plus they’re gorgeous compared to the skunks.

You’re definitely going to want an ITR intake manifold, 60+mm throttle body, and a good intake (stock size is just too small). I first dyno’d my motor w/ a stock ITR intake and it did quite well, but a velocity stack showed about 10hp gain, most of which should be able to be attained with a good 3" intake w/ normal cone filter. If you’re using the stock intake you’re just robbing yourself of the power your engine wants to put out.

And I wouldn’t recommend that comptech header unless it has a 2.5" collector. From what my tuner and friends have said it’s a huge benefit having that larger collector. I’m using a 2.5" collector (ITR replica), 2.5" SMSP cat, and RS*R exhaust and made excellent power with a setup very similar to what you’re planning. Nearly as much as my friend’s ITR engine w/ a 4-2-1 Comptech header (all other mods nearly the same).

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One quick sidenote that I touched on but didn’t clarify… Honda re-designed their LMA for the 99-00 civic si and made it like the Prelude ones, just a coil with no outer body. No need to use the Prelude LMA with a washer anymore. I’ll scan my computer when I get home and try to get you that part number. They aren’t as cheap as the Prelude ones, but still well worth it imo.

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Unified, I figured that was what you are talking about with the cams. I think you are probably right and you are helping me come back down to earth. I was so damn thankful that someone actually bothered to have an actual conversation with me that I kind of lost sight of my original goals after talking to Mike at King. You are probably right that the Skunk2 Pro 1 is just too radical for the rest of my package. I wasn’t even considering it before I made that phone call and those guys deal with crazy power all day which is why they consider the Pro 1 pretty mild.

I do find it interesting that the Tuner Stage 2 says fair-good drivability for street but the Pro 1 says very good drivability.

So Colin, do you have both CTR cams in now? ha ha. (Ran across your build in another thread)

I hear you about Skunk2; I’m also a little uneasy about them in general. My impression of them from 2002-04 (when I was last able to make time for all of this stuff) was not very good. Seemed like everyone had kind of jumped on their bandwagon but everywhere people were having shit breaking (especially suspension stuff and the cam gear problems like you had on those OG ones). My feeling had always been that they had the best cheap shit around. Seems like they have really stepped up with some of their stuff though (or their marketing is just fantastic) because it seems like no one really talks about anything else these days. The Pro cam gears look nothing like the ones you have pictured and seem decent. I do like the timing marks on the Todas though…

Mike from King was super into the Skunk2 cams as well, specifically the Pro 1s. He was telling me how those cams have kind of a bad rap because the timing was jacked on the first version and you could either make good power or make the car idle decently…but not both. But with the newer version it has all been sorted out.

I dunno. I should probably just pick up a set of CTR cams and call it a day. I guess I’m being kind of silly in resisting them; they probably are exactly what I actually need for the rest of the build.

Totally agree on the headers, but they’ll do until I see a decent set of fancy 4-2-1s come up for sale used. I originally picked them up because I have a nostalgic love for Comptech (1st gen racing) and they were cheap. Plus, 2.25" was what lots of people recommended back in the day for mild setups, I’m sure it’ll be fine for now. I’m not looking to change my name to Max Power or anything. :wink:

I’m not convinced the ITR intake manifold is what I want. I need to do some calculations after I get done at the Dyno the first time. Also, if peak torque isn’t where I want it with the stock manifold, I’ll look into it. I am considering getting the runners coated though in the stock manifold. I’ll wait on stuff like that; I see some value in seeing how each individual piece affects the whole package. That way if I put an ITR intake on and gain 15 HP but my power band moves up 700 rpms and I loose 10 ft-lbs of torque across the board, I’ll know that it is great for some people, but not for me…

Is your velocity stack an off the shelf part (if so, which), or is DIY? I saw you mention it in your other post and am intrigued.

With the Intake, I’ll wait and see; I’ll have to see what the appropriate size is for my TB once I decide what size it will be. But I’m sure something smoother on the inside than the stock one would be an improvement.

Thank you guys so much for chiming in. This is exactly the kind of advice that brought me back to this site after being gone for so long.

Robin

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Oh yeah, I am 100% on top of that one. The only reason I mentioned the Endyn ones is because I think he is just taking the $7 Prelude/NSX LMAs and adding the washer and selling them for $17. The Honda Civic ones are ~$22. The Acura Integra ones, (same part number as the civic) are ~$24. Part number for the new ones is: 14820-PCB-305

Thanks for looking out for me though. I will probably just end up getting the legitimate B-series ones.

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I’m currently running the CTR intake cam and the stock P61 exhaust cam. I had both but the exhaust cam was damaged. If I find a ctr/itr ex cam for cheap I’ll buy it, but considering the power I’m making already I don’t see it being worth much money to me as I doubt it’ll make much extra power.

Yeah, I probably wouldn’t hesitated to buy the Skunk2 cam gears, I just don’t really like their brand, there’s nothing that they make which strikes me as really nicely built, awesome looking or original. But like I said, the cams came very highly recommended, and a part like that I’d buy in a second if it’s the best. But I’ll pass on all the engine parts they sell that are just covered in their logo. But that’s just me, it’s personal preference, everyone has their brand loyalties and preferences.

Do you have a power goal? I’m beginning to believe that the whole concept of larger i/h/e leading to high hp but less torque is a bit of an old wives tale. I know there is some truth to it, but take this example.

Engine A
1.8 liter
2.25" collector
2.25" exhaust
2.75" intake
62mm throttle body
200. hp / 143.6 lbft

Engine B
1.7 liter
2.5" collector
2.25" exhaust
OEM ITR intake
60mm throttle body
188.4 hp / 139.1 lbft (properly tuned)
198.2 hp / 144.0 lbft (3" intake w/ velocity stack - not tuned)
200.2 hp / 144.5 lbft (3" intake w/ velocity stack, muffler removed - not tuned)

Both engines tuned on the same dyno, same tuner, same cams, same intake manifold, same compression… basically the same engines just different displacement and different bolt ons. The common thought about larger i/h/e and displacement would lead you to believe that the lower displacement motor will put out less torque & even less torque when combined with a larger header collector. That’s not what we see at all in those graphs. And yes, we’re talking peak torque numbers. However, if you look at the actual graphs the smaller motor made more torque in the lower rpm than the larger motor.

Additionally, the “not tuned” numbers quoted above may rise, there was a HUGE dip in power in the midrange due to the ECU retarding ignition. The engine was now seeing a ton more airflow and to be safe the ecu retarded timing to prevent detonation. If some time was spent to tune to that new airflow that dip would disappear as well as possibly increase power a little bit even at other spots on the curve.

Obviously, it’s still not a perfect comparison, there are lots of variables, but I still think there are some valid things to be learned by comparing the two motors. Also, with the velocity stack (same one) the 1.8l engine made about 210hp, I don’t have access to the graph or know the torque numbers though.

The velocity stack used for my dyno tune was one that the tuner had in the garage to show off with. it’s an aluminum piece of unknown origin.

On the 1.7

On the 1.8

I’m currently using a blox velocity stack + filter that I picked up for cheap. I have no idea if it’s better than the ITR intake or not, but I’ll be bringing it to the dyno next time. I also just put on an S2000 throttle body (same size as ITR) - but again, I have no idea of the power increase or lack thereof. But I would expect it to be a slight gain if I get it tuned for that size.

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Colin,

First off, that Skunk2 cam seal is fucking bad ass. Don’t tell me you don’t lust after one! You’re just too poor to rock that kind of bad as stuff! ha ha. Totally kidding.

All I have to go on right now is what I can read in books and learn online. Certainly the old notion of a car needing proper back pressure in the exhaust or it’ll loose significant torque has been dis-proven for all practical purposes as far as I’m concerned. Read an article that actually followed the scientific method to see what difference there actually was and it was minimal (this is on a V8 and they went up to like a 5" exhaust or something crazy like that).

There are ideals and there are things that work and in engineering, the two hardly ever meet. I think that is what those of us who are conscientious about what we do are doing are trying to figure out (I’m lumping you in this group, hope you don’t mind). Where does that boundary lie? Obviously runner length, plenum volume and throttle body diameter all play a part in not only how much power a car makes, but where it makes that power and how wide of a power band it really is. We know that slapping a 68mm TB on a stock B16 is going to just kill it but where is the line of diminishing returns? And then factor in costs…and reliability concerns. A juggling act to be sure. Maybe I’ll love what an ITR intake manifold does for me, but I want to make sure the math looks reasonable first and have a baseline on the dyno of what kind of difference it really makes. I’ve read that if your MAP sensor is at atmospheric pressure under load at WOT then there is no performance gains to be had with a bigger TB. Obviously throttle response will be different, but that logic makes sense to me.

Hmm, not really sure what my point was there…

Robin

P.S. I’m purposefully avoiding talking about your comparison for now because I’m tired and need something to do tomorrow morning at work anyway. In the meantime, here is a friend’s CRX who has an OBD-0 B16 with a 4-1 2.5" header, some kind of cheap ram air intake and CTR cams with stock cam gears tuned with BRE. Both headers and intake were on the parts car he got the B16 from, everything else is stock (assuming his TB is 58mm). That is ASE at the wheels numbers (not corrected for flywheel like the numbers you mention above). See that torque curve? That is the kind of torque curve I want! Basically flat from 2500 rpms to 7500. The black line is his personal tuning with an Ostrich 2 and an accelerometer app on his iPhone (no, I’m not kidding). Red is after an hour on the dyno. Just fuel and ignition timing, obviously.

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I’m glad to see this thread is going somewhere productive!

As far as the intake manifold is concerned, I really would spring for the ITR. After having a old school Skunk2, an ITR and an oem B16 manifold all next to eachother… The R is just too nice to ignore. Seeing the difference in the plenum and main air chamber when compared to the b16, it just makes sense to run the Type-R. A bigger TB is just extra icing on the cake imo… you’ll notice a better gain from swapping the manifolds, than you would swapping TB’s.

I agree with Colin, a 2.5" collector on your header would be a nice improvement as well. Thats why the Type-Rs (even the B16b Civic R motor) make more power with the 2.5" collectors and bigger manifolds with shorter runners.

Since we’re showing dyno graphs… this is the B16 we built…
Block:
B16 81.5 bore
Crower econo rods
JE 11:1 pistons

Head:
Port & Polished B16 Head
Skunk2 pro 1 cams
Pro series flat faced valves
Pro series springs and titamium retainers
3" cold air
70mm BDL throttle body
Skunk2 IM
Tri-y header with test pipe and 2.5 cat back.

Its just the final graph after a tune:

Even with all that air flowing through the motor, it had a hard time pushing those cams. Granted with the B17 it will be a little better due to the stroke being longer, but the overall compression will be about the same I believe.

Tuner 1s or '01 ITR (JDM ITR, CTR, same thing) cams, springs, retainers is what i’d recommend on your setup.

And like you said buymysoul, the Pro cam gears look different than the og ones that Colin posted… they’ve been redesigned and have been holding up well these days.

Sounds like a nice build you have going on though, it will be a solid motor when all is said and done.

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What I wanted to point out last night, but clearly didn’t due to exhaustion, is how the Pro1s performed in the motor I posted about. While it wasn’t a flat powerband, it built power pretty well. But the problem is that it never STOPS making power, and the vtec crossover is set at 7k because that is when the non-vtec lobes stop producing power as well… if the cams were a little less aggressive, I think the vtec crossover point could be dropped quite a bit and still make power to 9k.

So in the case of the build in question here, Pro1s would be too aggressive unless you were going to about 12:1 or higher. I’m not sure how much less aggressive the Tuner1s are… but I did the Type-Rs in my build… the '01 ITR/JDM ITR/CTR (all the same cam) and I really like the way they feel. the R is and was considered the best front engine fwd car for a reason… everything was designed and made to perform. On a relatively stock/mildly built vtec b-series, the Type-R cam is always a worthy choice.

Anywho, enough rambling, back to work heh.

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ha. Yeah, I wasted most of my morning composing a response and haven’t keep getting distracted. (hope for lunch right now)

I see your point. My other post (which I’ll put up after I get back to work and finish it) basically says that you’ve convinced me to stick with ITR parts. As you say, Honda does know what it is doing and has both reliability and performance in mind. Are the 2000-2001 USDM ITR cams also the same? If I end up being impatient and just buying new cams, they are much cheaper from the dealer than the new “JDM CTR” cams sold online.

Also, do you have any opinion about using the ITR intake springs on both sides? They are cheaper for one, but also are flat topped springs and I think may allow for a hair more lift (in case I decide to step up to a “Stage 1” cam later). My take is that in 97 and 98, the springs on both sides were the same and it wasn’t until 2000 that they upgraded the Intake springs…

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Im not sure about the springs… I don’t remember how aggressive the intake cam is compared to the exhaust cam… I simply assume they’re different for a reason lol. Could always get an aftermarket set, like the Todas you like. One less thing to upgrade down the road.

As far as the cams themselves… yes, the 2000-2001 USDM ITR cams are the exact same cam as the JDM CTR set. The CTR Intake (I think?) cam has a different part number, but the specs on the cam are the same… 273 degrees of duration, compared to the 270degrees of the '96 and '98 spec R.

15

This was from this morning, just saw your post above this one, I’ll think about the Todas…

Looks good. 197 seems pretty impressive for a B16. Shame the compression didn’t turn out where you guys expected it to. I’m not super experienced reading dyno grapsh, are there indicators in that graph that lead you to believe the engine is over cammed?

Interestingly, I was just playing around with a compression calculator and again I am perplexed as to why when you select all B17 components, you end up with a 9.6:1 CR. Also interesting is that if I was looking for higher compression, B16 rods would bump me up to 11.8:1 with stock (P61) pistons. Does it really work like that? I know I may be showing my ignorance here, but I’m curious (not that I’m considering this.) EDIT: NO! It does not work like this. What I didn’t notice is that while the compression may be reasonable; piston to deck height is negative meaning a (very small) part of the piston would actually be sticking out of the deck…so probably not a good idea. :wink:

I probably will eventually try out the ITR IM and TB. I’m certainly not trying to say I’ve ruled it out, just that I’d like to see what kind of difference it makes after the fact. It is easy to find comparisons between some of this stuff online, but you can never be sure of the agenda. There are enough conflicting opinions out there that I’ll have to just see for myself. There is no doubt that the B16 IM starts to not be able to physically deliver enough flow at ‘higher’ RPM, but I may find that I won’t need it…

Mostly as a result of talking with you and Colin, I think I have decided that I’m going to put a little more money into the actual headwork and be a little more reasonable on the valve train. If I decide my power isn’t where I want it or the amount I want, I can always make changes later. Fortunately cams don’t seem to really loose any value on the used market (when also purchsed used that is)

Alright, I’m going to start buying some parts today I think, nothing locks you into a plan like having parts you have to use. I’ll start this order with the ITR springs, the ‘new’ LMAs and all the gaskets I know I’ll need as well as all those darn annyoning heater hoses on the back. Those are a pain to change in the car and I know they are just ready to start leaking. :wink:

On a completely unrelated note, a coworker was just reading me this ten most annoying car owners article. I love the one for Civic owners. This is totally going to be me (emphasis is mine):

“Yo, check it. You feel that? No? Hold up, lemme do it again. Now? That’s that VTEC, dude! Yo how about these lights, man? I wired that up myself. Fresh as hell. Yeah, and I got those sweet new springs on there, dropped like, two inches. Hella flush. Tight. Rollin’ on Roti 18s, man. You don’t even know. See my wing out the rearview? Nah, that is the wing. It blocks the mirror, dude. That’s legit imitation carbon fiber, son.”

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Here’s a post I started last night but didn’t get a chance to finish:

Here’s my dyno sheet:

The red line is my base number using map for a different b17a. The green line is the curve I left with. The blue line is the curve w/ the velocity stack pictured above and everything else left the same. You can see pretty huge gains in midrange torque from 3500-4500rpm, and no noticeable loss below that. Then a dip in power from 4500-5400 rpm. Then another drastic increase from 5400 to redline.

That dip is what I was talking about before, it should be able to be tuned out and basically just make the curve smooth and continuous. You see a similar, yet less pronounced dip in the HP curve. It’s pretty obvious to me that the more restrictive intake was limiting midrange significantly. How that changes with a different intake manifold, I’m not sure, but I’d love to know. Man, it would be so awesome to have your own dyno and just be able to try out all sorts of combinations.

Now my comments from reading what was posted since last night.

Compression ratio calculators are notorious for being wrong, often they’ll have the specs on a certain part incorrect. I’ve always used c-speed’s: http://www.c-speedracing.com/howto/compcalc/compcalc.php But when I was dealing with this previously I used as many as I could find to make sure I was getting consistent numbers. I think I even did the research on the parts and made my own calculations.

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Man I don’t know why my work blocks flickr. So I could watch Hulu if I really didn’t care about my job, but I can’t look at flickr? Weird.

Man, having a dyno would be pimp. Maybe I can convince the significant other that it would be great exercise for her horse. I’ve always wondered if that would really be one horsepower…

I’ll have to check it out when I get home. I’m particularly interested in the B18 (I assume) vs B17 dynos. As you say, them being so close is definitely interesting. From your description it sounds like the B17 graph is probably the same one I saw in the build thread you posted to a while back.

My thought was that those two peaks in your graph was from the two different cams trying to make peak torque in two different areas. I don’t really know anything about reading dyno graphs though.

There is a formula to calculate the proper diameter of your intake based on the size of the throttle body opening (at the butterfly) but I’m sure having a smoother intake also helps the air accelerate faster. But as I said last night, calculations are all well and good, but sometimes it doesn’t really work that way. Fluid dynamics is complicated. Hell, that and thermo scared me enough that I became an electrical engineer instead of mechanical. :wink:

Speaking of accelerating air, have you ever heard anyone talk about using some of the fancy coatings from swaintech in intake manifold runners and intake ports? The guy from King talked about using their heat coatings on some forged pistons years ago but it actually worked so well the pistons never expanded properly (they should have accounted for this in their tolerances, but whatever). According to their website, I could get every coating they make for every engine part for under $1000. Somehow I think I’ll appreciate decent cams and valve springs better though. ha ha.

I’ve looked at several compression calculators including the c-speed and they all seem to calculate out to 9.6. The reason I was curious about it is according to them, P30s give 10.9:1, but you quote 11.1:1 and if I fudge the numbers to start off with 9.7, I do end up with 11.1 so I was kind of curious what the actual difference is. Is it the piston to deck height or something? I guess it doesn’t really matter for me, I’m going to get P30s regardless and the compression will just be what it is…

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Yes, the dyno is of my motor that you probably saw before. The 1.8 is a friend’s ITR motor, I can share the graph if you email me.

The peaks are definitely not due to vtec, they’re do to the extra airflow and the ecu retarding ignition timing in order not to lean out the air/fuel mixture. The ecu would need to be tuned for that additional airflow for it to be able to be taken advantage of.

In a similar fashion the basemap I was originally using for break in was tuned for a 12:1 (or higher) b17a. This engine didn’t like pump gas and the ecu was set to retard timing in the midrange to help protect the engine. Once my tuner fixed those settings I gained a lot of midrange power, the car felt much better. He was also able to lower my vtec engagement point giving me more time on my big cam. After seeing what gains I could make from an upgraded intake he said he’d probably be able to lower my vtec engagement even more.

Obviously it doesn’t really matter where your vtec engagement is, and the goal is to make smooth power and set vtec to achieve that. However, assuming you have a smooth curve, the lower you can set vtec the better. This means you have more useable rpm before dropping out of vtec. But that’s in my situation where the car’s purpose is track days, I want the car in vtec the entire time if possible. With that said I’m not looking for peak hp, I need power in as wide of an rpm band as possible since it’s not drag racing.

I haven’t heard much about those coatings, but the first thing that comes to mind is that it’s a waste of money unless you’re already running the best flowing parts to begin with. I wouldn’t look into that stuff unless you’ve already got the best parts and still need an improvement. But that’s my assumption, I could totally be off base with that.

I’m a little confused as to your beef with the compression ratio calculators. You keep mentioning 9.6:1. That’s basically the stock b17a compression ratio. I don’t get too bent out of shape about 0.1 compression on these calculators. I generally say that my CR is “nearly” 11:1. You are correct, it’s not exactly 11:1, but it rounds up to that. I’m running 0.25 oversize pistons, that extra displacement actually rounds my CR to 11:1 instead of 10.9:1. Either way, it’s splitting hairs.

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I’m with Colin there as well… .1 point of compression isn’t really worth getting too worried about. As I said earlier, depending on which cams you run, you’re useable compression ratio is different than the static ratio anyway. As long as you have a general idea (say, to the nearest .5) then you’re good.

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I guess I seemed more put out by that than I intended to. I was just curious as to why it was off (9.54 instead of closer to the Honda quote of 9.7)… I also thought that I had seen Colin quote 11.1:1 before, which worked out if you fudged things to make the stock setup 9.7:1, so I figured he knew something that I didn’t about what measurement to change. Perhaps Honda just calculated it wrong in the first place. :wink:

I didn’t think the peaks were due to VTEC, just mismatched cams – but your explination makes sense.

As far as the coatings, my thoughts are pretty much in line with yours; I just keep bringing them up because they intrigue me and eventually I’m going to run into someone who say “man, that stuff is so awesome, my intake air velocity increased by 5,00000% using that coating and my incoming air intake temperatures are now about 6 degrees Kelvin” or, conversely “I paid $1000 to have everything they offer done to my engine and it turns out it is all actually made of C4 and one day my engine pinged and the whole car ignited in a ball of flames.”

I am going to do the teflonesque piston skirts though. That makes sense to me on a very fundamental level, is reasonably priced and is done on many higher performance OEM pistons. Now maybe that is just a marketing ploy, but for like $21 it seems worth the risk if it cuts down on cylinder wall wear.