High compression???

[AR]

Any idea how much extra HP can be attained by increasing the ratio to 11.5 to one and addding cams, ems, injectors, etc.

Porsche runs 12 to 1 on the gt3 the S2000 is 11 to 1 AFAIK.

Maybe 350?

Cheers,

AR

[Senninha]

Ary,

In the Uk I would ask the guys at TDI as they have a well tuned FI NSX so real llife experience. Otherwise I would post the question on Prime

HTH, Paul

[markc]

It's hard to be very specific with NA tuning, it tends to be that an holistic approach yields the best result. It also tends to be expensive because you have to modify lots of things rather than just one :(

The very best high performance engines fitted to production road cars produce 110-120bhp/ltr. Think S2000, M3CSL, GT3 etc Perhaps an engine built without the need for a worldwide anyoldpunter warranty could make a reasonably reliable 125bhp/ltr. This sort of power would be made at high revs so the NSX's already high 8K range might need to be raised a touch. If this is beyond 8.5K it will need stronger con rod bolts at a minimum. You'd probably have to make the switch to individual throttle bodies (ITB's) as well to make 125bhp/ltr. Using these specific output per litre figures, a 3.0ltr could make 375bhp and a 3.2ltr 400bhp :)

More likely, a nicely balanced set of top end (breathing) mods which could include camshafts, valves, and cylinder head/inlet manifold porting with a free flowing exhaust/manifold combo and possibly a raised compression ratio could yield a 110bhp/ltr engine and therefore make 330bhp (3.0ltr) or 352bhp (3.2ltr).

It's unlikely that the injectors themselves are a limiting factor for these power levels but perhaps a higher capacity fuel pump would be a sensible upgrade. The NSX's 1990's vintage PGMFI ECU is probably not up to the job of making the most of this beast so a higher performance fuel/ignition computer (ECU) will likely be required to more accurately provide the fuel and ignition requirements. I don't think you'd need ITB's but the rumoured throttle body inlet restriction, as measured on our recent TDI dyno day, would have to be solved.

The other method of making more power is of course larger capacity. In the same standard state of tune (87.5bhp/litre), a 3.8ltr NSX engine would make 332.5bhp One with the similar mods to the above and 110bhp/ltr could make 418bhp

I'll settle for a 3.6ltr motor, running on a MOTEC ECU, making 111bhp/ltr and a nice round 400bhp :)

Not that I've thought about of course... :)

Mark

[NoelWatson]

It's hard to be very specific with NA tuning, it tends to be that an holistic approach yields the best result. It also tends to be expensive because you have to modify lots of things rather than just one :(

The very best high performance engines fitted to production road cars produce 110-120bhp/ltr. Think S2000, M3CSL, GT3 etc Perhaps an engine built without the need for a worldwide anyoldpunter warranty could make a reasonably reliable 125bhp/ltr. This sort of power would be made at high revs so the NSX's already high 8K range might need to be raised a touch. If this is beyond 8.5K it will need stronger con rod bolts at a minimum. You'd probably have to make the switch to individual throttle bodies (ITB's) as well to make 125bhp/ltr. Using these specific output per litre figures, a 3.0ltr could make 375bhp and a 3.2ltr 400bhp :)

More likely, a nicely balanced set of top end (breathing) mods which could include camshafts, valves, and cylinder head/inlet manifold porting with a free flowing exhaust/manifold combo and possibly a raised compression ratio could yield a 110bhp/ltr engine and therefore make 330bhp (3.0ltr) or 352bhp (3.2ltr).

It's unlikely that the injectors themselves are a limiting factor for these power levels but perhaps a higher capacity fuel pump would be a sensible upgrade. The NSX's 1990's vintage PGMFI ECU is probably not up to the job of making the most of this beast so a higher performance fuel/ignition computer (ECU) will likely be required to more accurately provide the fuel and ignition requirements. I don't think you'd need ITB's but the rumoured throttle body inlet restriction, as measured on our recent TDI dyno day, would have to be solved.

The other method of making more power is of course larger capacity. In the same standard state of tune (87.5bhp/litre), a 3.8ltr NSX engine would make 332.5bhp One with the similar mods to the above and 110bhp/ltr could make 418bhp

I'll settle for a 3.6ltr motor, running on a MOTEC ECU, making 111bhp/ltr and a nice round 400bhp :)

Not that I've thought about of course... :)

Mark

Not sure how accurate this is

http://www.442.com/oldsfaq/ofcrc.htm

[AR]

Paul already spoken to them :) I remember speaking to them in 2005 and when Amo was getting his I mention them, as they are IMHO a very knowledable and professional firm.

Mark I was thinking along those lines since the SOS stage 3 ( cams, valve springs and retainers ) nets 52 hp. Supposing that a 3.0 with I/H/E has an extra 20 BHP on the conservative side.

So iof we judge by the Dyno day resulsts and say that at the very least a 3.0 NSX will have 260 BHP accounting for transmission losses.

Then we increase the compression ratio and I think we will be there where you mentioned.

Noel thanks for the link, I found this one as well, I am sure either you or Mark will make better sense of it:

http://www.popularhotrodding.com/tech/0311_phr_compression_ratio_tech/index.html

It makes me wonder as to go FI without worries, one would need to spend well over £7K, for a low compression build up with EMS and tuning.

Why not NA if one must build the engine anyways.

Cheers,

AR

[AR]

It's hard to be very specific with NA tuning, it tends to be that an holistic approach yields the best result. It also tends to be expensive because you have to modify lots of things rather than just one

Mark

Mark the first thing on my shopping list either way is an AEM EMS, with AEM UEGO Wide Band Controller & Sensor, Fuel pump and RC injectors as well as a clean Throtle Body.

Those are needed no matter what for a little extra BHP.

The rest well it all depends on how sweet on can talk to the wife!!! :)

[markc]

TDI aren't big fans of the AEM kit they prefer MOTEC. They specifically mentioned the MOTEC M800 unit as their weapon of choice.

I think I'd probably be tempted to go for a mild cylinder head and inlet manifold port and polish before investing in new cams.

This thread on Prime talks about stock cams being able to make power upto 9K with headwork...

http://www.nsxprime.com/forums/showthread.php?t=81540&highlight=camshaft

Mark

[AR]

TDI aren't big fans of the AEM kit they prefer MOTEC. They specifically mentioned the MOTEC M800 unit as their weapon of choice.

I think I'd probably be tempted to go for a mild cylinder head and inlet manifold port and polish before investing in new cams.

This thread on Prime talks about stock cams being able to make power upto 9K with headwork...

http://www.nsxprime.com/forums/showthread.php?t=81540&highlight=camshaft

Mark

I mentioned AEM to them on the phone and they seemed OK with it. They already done one NSX with AEM. But I'll have a look at the motec £££.

[AR]

TDI aren't big fans of the AEM kit they prefer MOTEC. They specifically mentioned the MOTEC M800 unit as their weapon of choice.

Mark

Mark it looks as if the M800 would be more indicated for a DBW NSX, for what I have in mind the AEM is more than enough.

Cheers,

Ary

[simonprelude]

That's quite funny as it is 99% the same ECU and both are made by GEMS in the UK :)


TDI aren't big fans of the AEM kit they prefer MOTEC. They specifically mentioned the MOTEC M800 unit as their weapon of choice.

[markc]

Ahh, badge engineering! I love my Acura but wouldn't be seen dead in a Honda ;)

It could be that the physical electronics, of the AEM/MOTEC/GEM units, are almost identical but the software makes the differance. If you can't program these things easily and accurately they're useless.

Mark

[markdas]

Isn't this a bit of a balance with regard to either bhp per litre and bhp per tonne? Admitted with a 3 litre engine the 82bhp for litre can be beaten by quite a few days these days but I would think the bhp per tonne of an nsx is up there just behind things like Atoms, Westfields, Ultimata etc.

The big problem is using the extra power, especially off the line....certainly on a 1/4 sprint the NSX struggles with much more than standard as far as I can tell so far and a good driver (not me) can do a great deal with these cars as standard.

I am just wondering if additional speed or performance is desired, whether a theoretical 20-30 bhp improvement could be reached more cheaply by sheading more weight?

Just a thought

[Senninha]

I am just wondering if additional speed or performance is desired, whether a theoretical 20-30 bhp improvement could be reached more cheaply by sheading more weight?

Just a thought

This is one of the key areas I have looked at and and to date have shed around 135lbs from my NSX, plus over 16lbs from myself :)

I know Ary has been doing similar work and has shed >150lbs from his NSX

I'm hoping that this weight loss, the recent good TDI performance and some improvements to the overall aero package will yield good results at the Vmax run.

regards, Paul

[markdas]

So is there anyway you can measure an improvement...a kind of before an after 1/4 mile or track time? Also an estimate of how much the weight loss cost (of the car of course) because I guess CF is not cheap either? Sometimes though you have to trust the Honda did a good job of getting most things right with these?

[Senninha]

So is there anyway you can measure an improvement...a kind of before an after 1/4 mile or track time? ............... Sometimes though you have to trust the Honda did a good job of getting most things right with these?

All I can offer by way of comparison is that several owners have Vmaxed around the 160mph mark in both 3.0 and 3.2 coupes. Mine is the Targa (so heavier to start with), but if the changes/improvements deliver a better result then this would suggest that weight loss is possibly better than lots of re-engineering.

On the second point I would agree that Honda spent many years developing the NSX and significantly raising the bar for supercars of that era. Even today it is not far adrift. Its this belief in Honda's engineering that has guided me to use OEM parts for many of the changes to my NSX.

The other point that you made earlier is possibly even more important. The drivers skill level. For the Vmax this is limited IMO to being able to launch the NSX cleanly off the line. The real difference would be noted on track. No matter what any of us do in terms of weight reduction or power hikes, give an OEM 3.0 to a qualified and skilled driver and we would be left looking at their tail lights for the entire lap!

An example of this was given to me by Kevin recently. He did some driver training a few years back and over the course of a day improved his lap time by several seconds. At the end of the day he gave chase to his instructor who convincingly beat him round the lap. His instructor was using a VW Golf IIRC.

regards, Paul

[markdas]

Yep agree with all that.

Similar to the Top Gear episode where James May (Captain Slow) went to a track for the day in a TVR for some instruction from Jackie Stewart.....and by the end he had reduced his initial lap time by a huge amount! Its all in the driver really I guess.

Anyway....I have strict instructions not to even touch the dip stick for too long....I will stay content with the standard version for as long as I can!

Mark

[AR]

As good as it might be is also nice to have some extra ponies in there!

[Senninha]

Anyway....I have strict instructions not to even touch the dip stick for too long....I will stay content with the standard version for as long as I can! Mark

but remember, some things just wear out and need replacing .... and its often 'cheaper' to use aftermarket parts ;)

[AR]

but remember, some things just wear out and need replacing .... and its often 'cheaper' to use aftermarket parts ;)

Try that after 14 years together!!! She knows me too well and I can't disguise it when I get something new.

[markc]

You're quite correct that less weight is another route to higher performance but more power AND less weight give you a (good) double whammy. You can do either but why not do both? :)

Actually the NSX's power to weight ratio is pretty poor by todays standards, it's circa 200bhp/ton and not even close to an Atom or Caterham. The car manages to outperform it's suggested power to weight ratio by having a decent spread of torque and well matched gearing.

None of the suggested NA (Naturally Aspirated) tuning discussed in this thread would add any weight.

I know that there are some websites where you can pretty accurately estimate a cars performance by entering various factor such as power, weight, gearing, drag, frontal area etc. Tinker with the weight while keeping all the other parameters the same will demonstrate the straightline perfomance improvement. I'll see if I can find a website or spreadsheet.

Of course weight makes no differance at all to top speed. At the VMAX days you enter the timed straight at fairly high speed anyway so weight is going to have a negligable effect. Power and aero efficiency rule :)

As Paul says weight loss pays the biggest dividends in handling, specifically direction changes, acceleration and particularly braking. Another BIG (HUGE) advantage you can gain on a circuit without losing any weight or adding any power is tyres. Track biased or even slick tyres will make you car massively faster in the corners and unedr braking.

There's no skill in just going fast in a straight line so the driver, no matter how skilled, can't help. On a circuit it's a very differant matter.

Mark

[AR]

http://www.bgsoflex.com/aero.html

http://www.nsxprime.com/forums/showpost.php?p=982911&postcount=39

Enjoy!

[Senninha]

Another BIG (HUGE) advantage you can gain on a circuit without losing any weight or adding any power is tyres. Track biased or even slick tyres will make you car massively faster in the corners and under braking. Mark

Mark,

Do these tyres also help with top speed through either better contact area/grip? Would they maybe be lighter at all?

I will be needing tyres at some point and have been considering some more focused tyres as I do less 'daily' driving. Tyres currently being considered include the original NSX-R RE070, the newer RE055S or possibly Cup Sports as used by Porcshe.

regards, Paul

[AR]

RE055S

regards, Paul

Paul I had 520s on the NSX-R and it was sticky, very sticky! Be prepared for less mileage. Maybe two sets? Maybe you need some bronze TE-37 as your track wheels? :)

[markc]

Paul, I don't think that this type of tyre will help with top speed at at. The fact that they have a stickier compound, which will key into the road better, and sometimes run lower pressures giving a larger contact patch might actually hinder top speed a touch. I wouldn't use them if I were trying to wring out the last 1/10th of a mph :)

The construction of these tyres is similar to normal road tyresso they won't be much lighter either.

Any of the ones you mention or Pirelli's P Zero Nero, Dunlop RJ and Toyo's R888 will do the job depending on what size you're after.

I'm saving up to equip my spare 17"/18" wheels with a set. Having experienced Kevin's car on them (from the passenger seat at Bedford) I'll probably go with the Toyo's as they work well are good value.

Mark

[forumadmin]

Regarding the track tyres. The rubber used in them is for summer use only. If it's chilly the rubber will be hard and useless. Toyo recommend this on their website, and I can tell you from experience that RE070 in the cold and damp, is not a good tyre to be on.

Also to get the best out of track tyres as well you can be running anything up to 5deg of camber. Are you?

If we (me and Mo) were to start from scratch the upgrades to the car would be tyres (probably on fat wheels), suspension, brakes. In that order. Not much else makes the same amount of difference as these.

[NoelWatson]

For the Vmax this is limited IMO to being able to launch the NSX cleanly off the line.
regards, Paul

It's actually your speed off the corner coming onto the main straight - you launch about here

http://maps.google.co.uk/maps?f=q&hl=en&geocode=&q=bruntingthorpe&jsv=107&ie=UTF8&ll=52.484949,-1.14084&spn=0.003241,0.007253&t=h&z=17&iwloc=addr

so have to slow down for the corner

[NoelWatson]

It's hard to be very specific with NA tuning, it tends to be that an holistic approach yields the best result. It also tends to be expensive because you have to modify lots of things rather than just one :(

The very best high performance engines fitted to production road cars produce 110-120bhp/ltr. Think S2000, M3CSL, GT3 etc Perhaps an engine built without the need for a worldwide anyoldpunter warranty could make a reasonably reliable 125bhp/ltr. This sort of power would be made at high revs so the NSX's already high 8K range might need to be raised a touch. If this is beyond 8.5K it will need stronger con rod bolts at a minimum. You'd probably have to make the switch to individual throttle bodies (ITB's) as well to make 125bhp/ltr. Using these specific output per litre figures, a 3.0ltr could make 375bhp and a 3.2ltr 400bhp :)

More likely, a nicely balanced set of top end (breathing) mods which could include camshafts, valves, and cylinder head/inlet manifold porting with a free flowing exhaust/manifold combo and possibly a raised compression ratio could yield a 110bhp/ltr engine and therefore make 330bhp (3.0ltr) or 352bhp (3.2ltr).

It's unlikely that the injectors themselves are a limiting factor for these power levels but perhaps a higher capacity fuel pump would be a sensible upgrade. The NSX's 1990's vintage PGMFI ECU is probably not up to the job of making the most of this beast so a higher performance fuel/ignition computer (ECU) will likely be required to more accurately provide the fuel and ignition requirements. I don't think you'd need ITB's but the rumoured throttle body inlet restriction, as measured on our recent TDI dyno day, would have to be solved.

The other method of making more power is of course larger capacity. In the same standard state of tune (87.5bhp/litre), a 3.8ltr NSX engine would make 332.5bhp One with the similar mods to the above and 110bhp/ltr could make 418bhp

I'll settle for a 3.6ltr motor, running on a MOTEC ECU, making 111bhp/ltr and a nice round 400bhp :)

Not that I've thought about of course... :)

Mark

New NSX has >120bhp/litre

http://www.autoblog.com/2008/04/17/honda-nsx-to-spearhead-rwd-model-lineup/

Allegedly