Turbo Hybrid - Help please! :) (Long post)

Hi everyone… I’m in the process of building my 93 Integra, but I have a few questions I need to get answers to before I start installing the engine and stuff. First, heres a list of everything going into it: (Not including engine management):

B16 Shortblock:
Benson Sleeves
Micropolished/Chanfered crank
Balanced/Blue Printed
Crower Rods
Arias Pistons

VTEC Head from a 95 Delsol:
Custom grind Web cams (setup for forced induction)
Completely ported/polished Del Sol head
Stainless Steel swirl polished valves
Titanium valve springs/retainers

Complete Rev Hard Turbo kit (T3/4 Hybrid, using the Tial wastegate instead of the Deltagate)
Ported Type-R Intake

That’s everything I have so far, I’m still undecided on exhaust, and a few other things – This is why I’m making this post :slight_smile:

Heres the list of questions:

  1. The turbo kit comes with a 2.5” downpipe – I’m wondering, is that really going to be big enough? I’ve owned other turbo cars, and I’ve always seen good performance gains with a 3” downpipe (Faster spooling). Do you think I should have a 3” downpipe made? Or stick with the 2.5” one that came with the kit?

  2. I’m going from a non-vtec engine to a Vtec engine – I’m curious, if I hook up the stock (non-vtec) computer, without doing any wiring or anything for the Vtec solonoid and stuff, will I be able to drive the car? I hope to put the engine in, and drive it 400 miles to a shop to have a new ECU, Stage 4 Hondata, etc installed… I would LIKE to let them do the wiring to hook up the Vtec solonoid and stuff. Or will I need to do it to drive it out there? In theory, I should be able to drop the engine in, hook up everything I can (excluding the Vtec stuff) and be able to drive the car just fine… I’m just curious if it’ll really work like that

  3. I plan on running 24 PSI of boost at the track, what size injectors will I need to be able to do this safely? Are 720cc injectors going to be big enough? Or should I look at 800cc+ injectors?

  4. I plan on running some sort of aftermarket LSD, however, I’m not 100% sure which one to go with yet… Any suggestions? Also, is there anything I can do to the transmission itself to make it handle the horsepower better? I know Cryogenically treating the gears and stuff is possible, anything other than that? I hope to dyno around 450HP, and I have a bad feeling the stock transmission isnt going to hold up for a long time with those numbers. Any recommendations on a good tranny builder?

  5. Back to exhaust again – Who out there makes a 3” catback for these cars? Only company I know of is Thermal Research & Development. Any others? Only requirement is none of that annoying buzzing crap. If I want to hear a weedwacker, I’ll buy one :slight_smile: … The quieter the better, but I don’t want to give up much airflow to keep it quiet. Also, anyone know of a web page that has sound bytes of different exhaust systems on Hondas? It’d be nice to hear a couple to be able to make a decision.

Well, that’s all I can think of for now… I’m sure I’ll have more long posts soon! Hehe, this project got way bigger than I anticipated….

Thanks in advance guys/gals! :slight_smile:

  1. 2.5" downpipe should be fine, typically the backpressure is caused beyond the downpipe, ie.cat, resonator, muffler section of the exhaust. The thing is, when your boostin 24 psi at the track, I’d assume your going to unbolt the exhaust anyway, right? If you do decide to go bigger, check the downpipe DRAG supplies with it’s kit’s. I Have the DRAG kit and am pretty sure my downpipe is 3"

  2. Not sure about the ECU thing, I THINK I’ve heard people use stock non/VTEC ECu and a VTEC controller and have intermittent CEL’s, but the car will run. Like I said, not sure, though.

  3. 720’s should be more than enough. How much do you plan to boost off the track? Don’t want to go too big and bog on the street, you know.

  4. A good LSD to run is Quaife, usually run about $800. A sheaper alternative would be Cusco LSD, they usually go for $280. I’m a believer in you get what you pay for, though. Just a side note on the drivetrain issue you may want to address is the axles. I snapped mine pushing just 10psi. You may want to invest in some RACE units, can’t remember the company that makes em off hand, seen em in the mags, though.

  5. Yeah Thermal Reseach is the only company I’ve heard of that manufactures 3" exhausts for our cars.

Damn, sounds like your gonna have a beast of an engine when your all done. Keep us posted, good luck.

Thanks… Don’t suppose you happen to know of any place I can hear a sound byte of the Thermal R&D exhaust would ya? I’d love to be able to hear what it sounds like before I drop the cash for it :slight_smile: … Though, I guess it doesnt matter much since there arent really any other options for 3" exhaust…

Hmm, as far as how much boost I plan on running on the street, its hard to say really. When we dyno tune it after the Hondata installation, I want to set up 3 different engine maps… One for the track <24psi, racegas…> one for 18psi on regular gas, and one for 10psi regular gas… I’m sure most of the time on the street, i’ll only be running 10 psi or so, but depending on how good traction is, I might try 18psi…

Its really hard to say at this point… I’ve never even SEEN a turbocharged Honda in real life… So I have no idea what their like to drive with any amount of boost… And this is by far the wildest project I’ve ever done (a total of about $8500 has been spent for the engine/turbo kit so far… I plan on having $20,000 stuck into it by late spring (Car should be done completely around the end of April)… Its gunna be an adventure, thats for damn sure! :smiley:

I can’t believe how fast this project spiriled out of control… Started out, we just wanted to make the car faster, turned into this monstor race machine thing… Can’t wait till its done! :slight_smile:

Just curious, what setup do you have? <engine/turbo/etc…?> … I’d like to hear more about it… Any problems with your tranny holding all the power your making? I’m wondering what sort of beefing up of the drivetrain I can do <besides heavy duty axles… Is there anything we can do to beef up the trannys?> …

Sorry for sort of rambling on… Its been on a loooong week and I’m tired… Thanks for your time!!! I’ll keep everyone posted on the project…


yeah your car will run with an ls computer. you just won’t have vtec.

450 hp from a b16 is not the easiest of tasks, especially if you are using an off the shelf turbo from a revhard kit. have you thought about trying to locate a 1.8 block?

you do know that your 93 uses saturated injectors right? rc only makes your style injectors upto 550cc. any larger & you’ll have to wire up a resistor box from a car like a 90-91 integra (no idea how to do that) if you planned on using a hondata. with your power goals i would say a more complete fuel management system might be a better alternative. check out accel’s new dfi7, it looks really good. speedpro is also a nice option.

if you’re really set on those power goals, have a backup plan prepared for when things start to break (and they will). axles will snap so you should have spares at the track. and even you will have a fully built motor, you should tear it down after every season to inspect for bearing wear. a quaife diff is the best & if you have the funds, get it.

with proper knowledge, $20k is enough to propel a car into the 10s.

Yeh, I knew about the saturated injector problem - The shop whos going to install the Hondata said they could wire up the resistor box.

The reason I decided to go with the Hondata instead of the DFI or other engine management system, is because it will allow me to keep the stock idle circuit/enrichment stuff. In most areas this would be handled no problem by a DFI or something, however, I’ve heard from a couple people here in Wisconsin, that when it gets cold in winter, that the DFI’s have a real hard time getting the car to start and run consistantly. The people I’ve talked to say they always need to mess with the cold start richness from day to day during the winter. I’ve heard the Hondata will handle extreme cold conditions better.

Thats the main reason I chose the Hondata, the others are, the easily adjustable rev limiter/vtec engaugement points, the 2 step launch rev limiter, the full throttle shift ability, and the software it comes with appears to be pretty easy to deal with (and the datalogger rocks :slight_smile: ) …

I could be wrong about the DFI having the problems in winter, it could just be the people who I talked to didn’t have it tuned right. But, considering I’ve never set one up, I think its better to stick with the Hondata.

Just curious, what advantages would you say the DFI would have over the Hondata? <Besides the injector resistor box stuff> … Its not to late for me to decide on different engine management, but I haven’t heard a real great Hondata vs DFI (Or something else) arguement. Also, if you happen to know of a web page that has good information about the DFI, that’d be helpful.


PS. The car will <hopefully> be a daily driver year round, so the ability to idle is important, also, I don’t want to have to retune the car completely every time the weather changes 20 degrees… Those are the basic requirements for me :slight_smile:

benefits? well for one thing when you get an aftermarket system you will get a system with a wideband o2 sensor for tuning. that is something like a $1300 option with hondata. for instance, speedpro uses this sensor to basically “tune itself.” you type in the desired a/f ratio into the tuning map & it will automatically make corrections to that map to reach that a/f ratio. then you can alter the map values in an attempt to make the correction factor as small as possible. also, these map sensors are durable enough to be run with leaded racegas, which cannot be said for the typical stock one on your car now.

now add to that the laptop tuneability of these other systems without the need to burn a new rom for every time a change is made/part is added to your setup & you begin to see the better flexibility offered from a true standalone.

as for idling/starting, a bank-to-bank system such as the lower model speedpro still will do an adequete job of idling large injectors, and sequential is an option if so desired. dfi version 7 comes with sequential operation. the truth is though, anytime you have such large injectors on a motor that wasn’t designed to operate with them, you will sometimes have starting problems. i wouldn’t really want to drive a 300hp front wheel drive car in the snowy seasons much anyways…

most standalone systems will come with rev limiters, but its better to use an ignition controlled rev limiter so spark is cut instead of fuel. and some standalone systems do offer vtec control as well (haltech). if not, then a simple rpm activated switch can be used.

check out these sites for more info:

also, aem is coming out with a system as well, but no info is available on their site yet…