cylinder heads

[EDRNSX1]

i put on this section since i dont see an "engine" section... im a m/c guy so dont laugh (you can on several bikes!)

Can you use the newer cylinder heads on a 1995? I have a set of 1999 heads in my garage.

Again, could be way out of line..but hey, even the GSXR's you can swap heads from years and 750cc or 1000cc so i thought i'd ask.. i mean, i got them and port heads all day long, can do my own machine work and flow benching..might be fun to do up this set of heads and then swap over.

If not..thanks and hope ya'll get a good laugh..but until you kids can get over 220rwhp per liter NA ill keep my head up...lol thanks!

 

[prestonmay]

i have done the same on 3 of my bikes. took a spill and wifey made me get rid of the bikes---SO the NSX SC feel was the closest I could get to being on a bike feeling.....

I wondered the same , but was shy to ask.:redface:

 

[David]

All the cylinder head castings are the same. The later ones have (slightly) bigger valves, but I believe everything else is the same.

As for porting, you probably won't see any real gains unless you go to bigger cams. The stock heads flow pretty well already. If they were mine, I would just blend the seats, correct any casting drift/flaws, match the ports, throw in a bigger set of cams and call it a day.

PM me if you want some input on cam selection.

Best of luck with your project.

 

[EDRNSX1]

All the cylinder head castings are the same. The later ones have (slightly) bigger valves, but I believe everything else is the same.

As for porting, you probably won't see any real gains unless you go to bigger cams. The stock heads flow pretty well already. If they were mine, I would just blend the seats, correct any casting drift/flaws, match the ports, throw in a bigger set of cams and call it a day.

PM me if you want some input on cam selection.

Best of luck with your project.

Cool thanks. As for "not gaining much hp" lol..im willing to bet i can. Honestly, even thou the NSX is an AMAZING car...the heads are NOT that impressive....seriously, they are production heads. Besides, i dont mind even if i get 5 hp...i do this for living (yeah yeah...little motors of course) but its all about i have them...and the tools/knowledge so why not?? besides mine has 70K on it...so it would be great time to install new head gaskets, maybe better studs, do some great head work, a good (fresh!) valve job (full radius), then throw in some cams, time them, etc...cams would be only cost out of my pocket...and most the fun is knowing i did it...not just bolted on something someone else did :biggrin:

Thanks for heads up...the valve size i knew was different but so long as your ptv is ok, i figured it'd be fine...no not 100% perfect due to included angle if different but so long as the most important thing ptv is ok then good too go.

Ill have to hit up the old HS friend of friends Shad about PTV clearences...we run our AMA 600cc bikes as tight as .030" but thinking might be too tight for big motors...lol


Heck, i got a whole 3.2l motor...maybe ill just build the whole thing (ti rods dont scare me...use/set them up all the time) and put that in there? hmmm..build for high hp NA or build low comp. boost motor??...hmmmm...need more time in the weeks!

thanks guys

 

[greenberet]

In case you haven't seen it, there's some interesting information on building performance NSX engines on this web page.

 

[BluryNSX]

In case you haven't seen it, there's some interesting information on building performance NSX engines on this web page.

great website!

to the OP, I am interested to see what kind of gains you recieve from porting the heads, on all my previous builds it was always a significant gain but it seems as though not alot of people have tried it on prime(unsure why not) but I myself would love to see the results of that kind of test with and without cams.. I am planning a direct port setup and wanted to have some port work done (no polish to create more turbulence) but from what I have seen noone has done alot in that area and for the cost involved if gains aren't significant I may or may not do it based on your results.

 

[docjohn]

I have heard that some people have put 3.0 heads on 3.2l short blocks,which raises compression slightly,might be a thought if you were going to go NA with cams.

 

[BluryNSX]

I have heard that some people have put 3.0 heads on 3.2l short blocks,which raises compression slightly,might be a thought if you were going to go NA with cams.

wouldn't that decrease cam option as well as decrease the adjustability with the cams? also if that is the case wouldn't using 3.2 heads decrease compression therefore allowing more cam adjustability/options?? maybe I am talking out of my a$$ this is all just based on what I have read I have no real hands on unfortunately.:frown:

 

[docjohn]

wouldn't that decrease cam option as well as decrease the adjustability with the cams? also if that is the case wouldn't using 3.2 heads decrease compression therefore allowing more cam adjustability/options?? maybe I am talking out of my a$$ this is all just based on what I have read I have no real hands on unfortunately.:frown:

No you just use 3.0 cams /double springs.Shad had discussed it with me inbetween my myriad engine rebuilds.

 

[EDRNSX1]

I have heard that some people have put 3.0 heads on 3.2l short blocks,which raises compression slightly,might be a thought if you were going to go NA with cams.

most likely it has a smaller CC. anytime you put a smaller CC on a bigger bore your gonna dramatically increase compression.

Thanks for the pm's guys. I honestly didnt even consider VtV issues....lol guess i work on too high tech stuff..you know heads that flow up over 15,000rpm and also have an included valve angle under 15degs so VtV is never really an issue..we cant run huge cams mainly due to small(ish) tappet buckets dont allow us to run a huge dur/lift cam without running "off" the buckets...but still i think ill build the entire motor up (3.2l) for a boosted motor..i can get parts at cost (hell, JE sponsors us..maybe ill beg them for some "BIG" pistons..you know something finally over 70mm)

Thanks again guys...sorry if too "nerdy" talking on engines..its what i do...and its FUN to do a car motor since i do about 55 race engines a year for bikes..now for a REAL challenge..maybe i could fit "desmo" valve train from our Ducati 848 to it and then never ever worry about valve float...ROFL...jk

 

[ScienceofSpeed]

The later 3.2L have air injection ports, these can be welded closed if you are using them on an earlier car. The cams and valvetrain are identical between 3.0L and 3.2L. Only the A/T vs M/T differ.

Cheers,
-- Chris

 

[EDRNSX1]

The later 3.2L have air injection ports, these can be welded closed if you are using them on an earlier car. The cams and valvetrain are identical between 3.0L and 3.2L. Only the A/T vs M/T differ.

Cheers,
-- Chris

Figures Honda puts AIJ in them...lol we have to bypass this on the bikes all the time..annoying...but all in the name of clean air..as i sit behind a public bus puking out raw emissions!