I recently snapped my timing belt and replaced the head of my 90 LS with a 01 LS head. Am I going to see any difference in performance with the newer head on? My old head had a miracle snap that when we took the head off all the valves were perfectly fine (not a single bent one) but I threw on the other head anyways because it was newer.
Im guessing you went from a pr4 head to a p75 (im pretty sure)… which are basically the same, minor difference in one of the cams and a different design intake manifold and throttle body.
If you used the newer intake manifold (which apparently flows alittle better) … u might gain something, but probably unnoticable, if anything at least your new head is 10 years younger than your last. Valves etc might have less wear.
Not really a good answer, but i hope it helps.
I think the newer LS motors from the DC integras had 10 more horses due to the cams and maybe something else but I’m not 100% sure. I know they were rated at 140hp instead of the 130hp. Maybe someone can shed more light on this subject.
This is a question that has come up all time while ive been reading through the forums. One of the cams is slightly different (not sure which one, int/exh), and the intake manifold is definantly different. and the move from a 58mm to 60mm throttle body was added in there somewhere too.
The biggest difference i think would be the moves from OBD0 the OBD1 and then OBD2 … running different engine maps can give or take 10hp easily, any tuner (not me) can agree on this.
[QUOTE=Denied;2320900]…The biggest difference i think would be the moves from OBD0 the OBD1 and then OBD2 … running different engine maps can give or take 10hp easily, any tuner (not me) can agree on this.[/QUOTE]I would agree with that. The fuel maps can make a big difference in horsepower, which is why on some cars, people keep two ECUs. One to pass emissions, and a second one for higher engine output. If the cams are different, there is really no easy way to predict the outcome without matching the fuel map and ignition timing to the cams. Peak output could actually go down.
the intake cam utilizes lobe profiles with higher lift.
the intake manifold is a more efficient design with larger runners.
as well, i believe the actual cast may be different. or at least the intake ports, to accomidate the larger runners and cam profile. don’t quote me on that last bit tho. it’s been awhile. would make sense tho.
also, of course, engine management
something people need to keep in mind as well about engine management and fuel maps, is that the manufacturers main concern is not hp or torque. cost, rmissions, noise and driveability would likely rank above.
some factory maps just look terrible from a power point of view.
I dont mean to go off topic, but does anyone have any good links or info where i can learn alittle about the tuning side of things, like engine mapping etc… what the tuner is trying to achive (perfect a/f ratios? , perfect timing through the rev range?)etc…
Any help, or a point in the right direction would be much appreciated.
Thanks
[QUOTE=welfare;2320926]something people need to keep in mind as well about engine management and fuel maps, is that the manufacturers main concern is not hp or torque. cost, emissions, noise and driveability would likely rank above.
some factory maps just look terrible from a power point of view.[/QUOTE]Yes, and considering the OP wants his car to be a little more competitive against similar cars/engines, I would say that talking to a tuner would be the next logical step. Something that works just fine on the street on a dd, can just be f-ing embarassing at the track if you end up losing a few hp instead of gaining a few, and suddenly youre losing to cars you were beating a few weeks ago.
[QUOTE=Denied;2320927]I dont mean to go off topic, but does anyone have any good links or info where i can learn alittle about the tuning side of things, like engine mapping etc… [/QUOTE]You could just start with the hondata.com web site. Its there to promote their products, but there is a LOT of information there. Fairly easy to navigate, and you can do google searches like “hondata fuel map”, etc. (note, they do not cover '90-91 model ecus, but the generic info is good).
Also, Honda/Acura Engine Performance by M. Kojima, still available used in paperback online (just checked to be sure).
Wow! Just got back to this thread and yes, I do believe the cam(s) have a slightly different profile which gives the 10 extra hp. That I already knew coming into this but wanted to know if there was anything else I should look out for or things that I can do to this head that I could not do to the other. Thank you very much guys. The input is greatly appreciated.
What i think we have all agreed upon is that there is a slight difference in one of the cams, but the cam itself is not going to get you that 10hp your chasing, i doubt it would add anything really…
That 10hp comes from the combination of all the things weve brought up… they changed the intake manifold, went from a 58mm to a 60mm throttle body as well as a whole new OBD system running what id assume to be a better fuel map too.
ALL of that combined added 10hp… changing one cam (and not even having your car tuned to make use of it anyway), i very much doubt it would do anything, the jump to the 60mm throttle body probably played a bigger part in the increase in hp than the cam alone would have. Ive read hundreds of threads on this topic, and everyone has there own opinion (hell i could be dead wrong too!), but my view is that all the minor changes added up and working together got them that extra power.
I was going to do the same thing a while ago, swap a B18b/1 head onto my B18a1 block, but i just got the intake manifold and throttle body, and im saving for some real cams eventually.
You did good by upgading, its gotta be fresher than your old one, and thats where youll get your benifits… did you swap the intake manifold and throttle body too?
swapping the intake cam would still make some difference. the fuel maps are just base maps. there is still correction in fuel delivery made by the ecm depending on what it sees from the o2. mind you, if you’re dealing with a single wire o2, the ecm will only see a small window of closed loop time
[QUOTE=Denied;2320963]…a whole new OBD system running what id assume to be a better fuel map too. [/QUOTE]I would say the OP would get best info posting a question where one of the tuners can see it. Hondata tuned ECUs were only available for OBD1 and later engines, probably for good reason.
@Denied: In an OBD0, 90-91 Integra, I think you will need an OBD1 ecu, a small wiring harness adapter, an OBD1 distributor, the intake, and 92 or later head, before you even get the Hondata or similar “accessories” and start tweaking the fuel maps… (not a big deal for a man who is fabbing his own adapters and blockoff plates and throwing perfectly good antique engine parts into the dustbin)
Not quite the Frankenstein solution, but it is a slippery slope!.. 
I don’t know if the OP wants to go that route, which is why I would say again… talk to a tuner, or someone with a tuned car.
to go obd0 to obd1, you need an obd1 ecm, obd0 to obd1 conversion harness, obd1 distributor, 4 wire o2 sensor. that’s pretty much it.
you can use an obd1 engine harness instead of buying a conversion harness if you want. that way the distributor connectors match up. instead of repinning the obd1 distributor to the obd0 connector, or buying a conversion harness for it. this also enables you to just plug in your 4 wire o2, instead of wiring it to the conversion harness. also, i believe obd1 ecm is designed to run low impedence injectors, so the resistor box would need to be deleted. another task that would be bypassed by using an oe harness.
it’s a bit more work. but it’s cheaper, and much less room for issues
you can still tune and datalog on obd0 though. tbh, obd0 and obd1 are exactly the same. only difference is the 4wire o2 sensor.
obd2 is where all the real changes were made.
Lol @ PMI , hey ive still got all the old parts in a box! But yea, things escalate pretty quickly! I shouldve have never bought that cam seal!, it all started there… now ive got the head in my kitchen, top end plactically rebuilt, all cuz the cam seal leaked!
Ive got a 92 so OBD1, would be real easy to do the swap for me, pretty sure everything will bolt and plug straight in.
Ive been reading up alot more on engine tuning now, and i think it amazing what can be done with a laptop… i grew up with carbys and V8s, a simpler time when all you needed was a vacuum gauge!
[QUOTE=Denied;2320987]Ive been reading up alot more on engine tuning now, and i think it amazing what can be done with a laptop… i grew up with carbys and V8s, a simpler time when all you needed was a vacuum gauge![/QUOTE]Yea, you are definitely on your way down that rabbit hole… chuckle.
[QUOTE=welfare;2320975]…i believe obd1 ecm is designed to run low impedence injectors, so the resistor box would need to be deleted. another task that would be bypassed by using an oe harness…[/QUOTE]I did not know that - The injector part numbers are different, although I did not know there was no resistor pack, which presumably means different wiring. Fuel injectors for the 92 and later cars are a lot more expensive, so if that turns out to be a necessary item to take advantage of the obd1/obd2 ecus and heads, it would raise the cost of a conversion substantially. (not really sure whats the right way here, or if you are saying its just a cleaner option to using the orig harness with old injectrs and leaving the box in place?)
sorry, i got that wrong. obd1 ecm’s are typically designed to run high impedence injectors. meaning if you want to run your low impedence obd0 injectors, you must KEEP the resistor box in place and hooked up. otherwise the ecm’s drivers will burn out due to excessive current draw from the low resistance injectors.
if you want to run a full obd1 engine harness instead of buying/making a conversion harness, you must use high impedence obd1 injectors. or wire in a resistor box
[QUOTE=welfare;2321000]if you want to run a full obd1 engine harness instead of buying/making a conversion harness, you must use high impedence obd1 injectors. or wire in a resistor box[/QUOTE]Thanks, now is makes sense to me, 
