Road not taken 400hp NA?? Cams Ported heads ect.

[AJKS]

Has anyone out there went crazy yet and put the Toda or Comptech cams on their NSX and or port the heads.
Also a little known fact that there are alot of other engine parts in Japan for the NSX like larger throttle bodies, modified intake manifolds, high compression pistons, all together repoted to put the 3.0/3.2 up to 400hp normally aspirated.
400hp with no FI....now thats what I am talkin about!!!!!!

 

[Ponyboy]

I've heard of a couple of people out there but I'm not sure if they frequent the forum. When I called Comptech I was told the cams alone will produce around 320hp. I don't remember if that was rear wheel or flywheel but I'd think it was fly considering their SC output. I don't think the Toda cams are out yet, at least according to the King Motorsports web site.

I like the idea of going 400hp NA but would really like to see the dyno graph on such a car. My concern would be the torque curve and if it'll just amplify the present stock one or produce goobs of power just up high or goobs down low too.

 

[David]

The Japanes parts are harldy a secreat and I suspect most of the people on this board are familiar with them. Frankly, most of the Japanese parts I have seen (Toda, Revolution, etc.) are of no higher quality than most US aftermarket parts and some (Revolution throttle kit) are just not as good.

You could use well-know domestic builders and get 400 hp without a lot of fuss. I don not consider that a major challange. It just costs money.

 

[matteni]

I knew of at least one member who did the full Comptech internal engine modification IEM kit and only got about 1/5th of what their dyno promissed - all top end too. I think the benifits of a SuperCharger adding low end, under the curve, seat of the pants torque are well documented as well.

Good luck - hopefully somebody with the IEM mods will chime in.

 

[Lud]

I believe Mark Johnson (Dali Racing) has mentioned he was not happy with his IEM job, but others seem to have had much better experiences. See this thread for some other comments and dyno: http://www.nsxprime.com/ubb/Forum1/HTML/005596.html


I've heard several people in the US say they were going to pursue the ~400 HP naturally aspirated build-up, but people who have actually done it seem to be very few and far between... As David said it wouldn't be cheap, and I suspect it's going to be a lot of top-end power and not much on the low end.

[This message has been edited by Lud (edited 13 February 2003).]

 

[zoomnsx]

Originally posted by Ponyboy:
My concern would be the torque curve and if it'll just amplify the present stock one or produce goobs of power just up high or goobs down low too.[/B]

............................................
One of the best ways in getting a good low end torque is by increasing the stroke. Unless the IEM involves using a stroker kit, there won't be a major change in the low end.

 

[SpankyPop]

I would wonder about stroking due to its effects on the rod/stroke ratio. THere truly is no replacement for displacement, perhaps boring would net you better results? Does anyone know how much a nsx can be over bored?

 

[lowellhigh79]

326 rwhp @ 9200 rpm. Full motec, full head job, larger TB (welded). We did this back in 95

No difference down low, Vtec a little more pronounced,great from 7000 to 9200.

 

[David]

Originally posted by SpankyPop:
I would wonder about stroking due to its effects on the rod/stroke ratio. THere truly is no replacement for displacement, perhaps boring would net you better results? Does anyone know how much a nsx can be over bored?

I know at least one block has gone to 3.3L with no increase in stroke. You might call Darton and ask them how far they believe you could reliably go with their sleeves.

 

[zoomnsx]

Originally posted by SpankyPop:
THere truly is no replacement for displacement.[/B]

Displacement = bore X stroke

 

[zoomnsx]

Originally posted by lowellhigh79:
No difference down low, [/B]

Do you mean no increase or decrease in torque?

 

[jdnsx]

How much does this cost and who can do it?


326 rwhp @ 9200 rpm. Full motec, full head job, larger TB (welded). We did this back in 95 No difference down low, Vtec a little more pronounced,great from 7000 to 9200.

 

[lowellhigh79]

Originally posted by jdnsx:
How much does this cost and who can do it?

Lots of money and time. The Motec unit alone costs 4K. Most any engine builder can P/P heads, and intake manifold. SS swirled valves are now readily available too. You will find that trying to wring hp out of the NSX NA is low bang for the buck. Stick with the forced induction. There is nothing (HP and torque)increased nor decreased down low. About 6000, the switch to Vtec is more pronounced. No drop off at 7200, still climbing with a steeper slope. We ended up increasing the redline to see where the curve would start to drop off, about 9100. Additional inline fuel pump did not help much. This is a good mod for road racing only, where you can live above 5000. Also, the sound from the side vent is phenomenal.

 

[David]

Originally posted by jdnsx:
How much does this cost and who can do it?

Not hard at all to do. Just hook up with the right folks and be ready to write some checks.

1) Go with AEM, not Motec if you are 91-94. It does everything the Motec does, except traction control, uses the stock harness and costs much, much less.

2) Headwork is easy. Find someone who knows Honda heads and has a good rep building NA horsepower. I would probably use BCE, Dan Paramore, Portflow or Alaniz. Might want to go with bigger valves while you're at it. Definitely want to upgrade the springs.

3) The bump sticks are a bit trickier. You could get the CT ones or work with a good cam guy and work up your own specs. Leave the first profile alone and only modify the VTEC lobes.

4) Call Darton about getting sleeves with a bigger bore. If they don't work out, try AEBS or Golden Eagle.

5) JE or Arias can build high compression pistons for you.

6) Hold off on the intake for now. There is going to be a neat NA solution for this later this year.

Done. Now go drive real fast.

[This message has been edited by David (edited 14 February 2003).]