NSX track project help required

[f1racr]

Hi all,

Well as you'll no doubt see by my post count I'm new to the forum.

I am a current Honda owner with a modified Civic Type R EP3, and also a Skyline GTR owner also, but am in the throws of putting together my next project car and I've always loved the NSX and so me and a friend have decided to build a car dedicated to track and road race use.

The main reason for this is that over here in NZ to be able to road register an NSX it has to be a 1998 or later model and it's simply going to blow our budget out if we have to purchase something like that, so we're looking at purchasing an earlier model and making it exclusively for track use.

We'll be able to get a dispensation from the government to be able to drive it to and from event and between stages on open road events so that's all we'll need.

What I'm really after is hearing from anyone who has any experience modifying NSX's for race use. Are there any known issues with the NSX ? I heard someone mention that with heavy use, they can overheat ......no idea if that's true, but really want to understand what I'm getting myself into before we go ahead an purchase the car.

The plan is to probably drop the factory engine and look at purchasing a complete engine from or a rebuild from a specialist in the US possibly or if I can find enough information, I'll have my engine builder here look at it.

In short I'm hoping that you guys might be able to tell me if it's fairly straight forward or simply too hard and expensive to make an NSX into a reliable track day car. I'm not wanting to compete in endurance events or a full on race series, but I do want to be able to compete in our annual Targa road race event which allows you to drive as fast as you want on closed roads, and not have to worry about the car getting too hot, or melting, starving of oil or other such dramas.

Any help is much appreciated. I'm going to continue searching through the forums as there seems to be a lot of information for me already.

Just a final note, my plan is to supercharge the car also, nothing to mad, probably around the 500-550HP at the flywheel kinda power.

I'll add pics of the Civic and GTR in a minute.

Thanks in advance for any advice.

 

[f1racr]

 

[MichaelD]

Don't know how to answer your question, but the Skyline is HOT!! Good luck with the new project!

 

[docjohn]

I have actualy watched some targa events that are on speed TV.I have always felt that a good nsx setup for the changing conditions and rough roads would simply be a lightened 91-94 coupe with a simple bbk and a simple yet strong susp like the oem type R.Get the other non compliance stuff,rear beam ect toe links front pivot clamps,and stuff the biggest R compound tires in the wells.Bolt the required safety cage and fire suspresion and you are off!There are a few prime members who have built track cars.Search for posts on track cars plus pm Rob Morrison,as well as vintage racer NY.PM titanium Dave and Kip Olson all these guys have wealth of knowledge on building up the nsx for racing.

 

[NSXDreamer2]

are you planning on retaining the ABS system, I don't have much problem with my limited skill at my local track, but na2 system is a better system.

oil pump gear, harmonic balancer are a few items that you want to replace if you are going to have the engine out anyway, maybe upgrading the engine mounts too.

accusump and baffled oil pan is the best solution against the oil starvation...

Since you are planning to rebuild or buying another engine, maybe just slaping a set of nice suspension, BBK and short gears, and enter the car that way and see what you need for the Targa race?? eg. built na, or FI... etc...

 

[stuntman]

Moton ClubSport Dampers (dual-adjustable)
235/40-17f 17X8
275/35-18r 18x9.5 (or wider)
Brembo BBK (off the shelf Lotus kit or Titanium Dave's "F50/Lotus" kit)

have fun... they're great track cars.

 

[eNeSeX 95T]

Look up the Dali Boostzilla Supercharger. Probably gonna be the closest to 550 ull get with a supercharger.

 

[MCM]

Any solid coupe, minor susp & exhaust work, & a loose nut behind the wheel and your all set!

 

[Swift]

besides the norm of making any car a race car(stripping/roll cage)..

Good suspension, BBK, exhaust, sway bars are obvious as well.

The engine and tuning/building a few member should come in shortly to help you with that and the best options for what you want and the style of racing you will be doing.

Ps-this engine is open deck and MAY have overheating causing BHG due to cylinder sleeve shift though very rare. Options are there to add sleeves and make it a closed deck to gain reliability under hard track use.

 

[f1racr]

Wow thanks so much guys for the useful posts............

I certainly will be doing some more reading and contacting who I can for more information as I would like to make a realistic assessment of what costs and techical challenges I'm likely to face along the way.

I'll post back as is needed for more info, decisions are made (they'll be up for discussion if you think it's a bad call) or as things develop.

Thanks again

 

[nsxtasy]

If the NSX is in good condition and all the scheduled maintenance (including the timing belt and water pump) has been done, there's almost nothing you need to do to make it reliable. I would change the cooling system hoses if they've never been done, and the crankshaft pulley, and fresh brake fluid (preferably high-temp stuff like Motul RBF 600) and that will do it. If you want to change things to upgrade the performance - the drivetrain power and/or the suspension and/or losing weight and/or R compound tires and/or brake pads/rotors/calipers - by all means feel free to do so, but if your question was only about reliability, that's about it.

 

[f1racr]

Brilliant, it was a bit about both, but that's very useful to know.......... my primary questions was about whether there was any issues to worry about with the NSX, the second part was really about what needs to be done to make them reliable when on the track.

Thanks for the reply mate, much appreciated, it's helping me to form my impressions of the NSX in general.

 

[titaniumdave]

I agree with all that has been said so far. Base NSX is a great track toy.

If you are going dedicated track rat, the best upgrade is to drop weight. There are a number of sub 2500 lb. race cars out there, that is by far the best thing to do to make the car handle and accelerate. I have done lots of mods on my car and others, I think the most fun car to drive I have been in is Gary Yates (ncdogdoc) stripped track rat. He has a little extra power, full mono-ball suspension, Koni-coil overs, huge front sway, racing cage, race seats, some aero body parts, rear wing. He is still running stock calipers with lots of ducting and his brakes are fine. The need for big brakes is greatly reduced by dropping weight. I still like mine If you stay stock, you have lots of very cheap tire solutions out there too, and the stock wheels are about as light as you can get, lighter car does not need real big tires to get max lateral accelerations too. Light wheels and tires do great things for traction as well, especially on rough surfaces.

If I was starting over on a track build, this would be my list and order(more or less):
Chassis
1.strip the car, that was not needed!
2.full mono-ball suspension-remove all the rubber from the pivots, offset for more -camber, and caster adjustment, compliance front clamps, yes, I make all these:biggrin:
3.good coil overs with adjustable spring height,(Motons are great!), 1000 lb front, 600 lb rear springs to start
4.the biggest front sway bar you can find...I will have 1 1/4" bladed ones this summer:biggrin:
5.race seats and 6 point harnesses, start with a basic harness bar and sub mounts, oh yah, I make these too
6.smaller,lighter wheel with a QR hub
7.type R chassis braces

Engine
1.headers on a NA1, NA2 headers are OK
2.exhaust, lighter and free-er flowing
3.intake airbox
4.clean the injectors and have them flow matched!
5.baffled oil pan and Accusump set up, me again:wink:
6.external oil cooler
7.valve cover breather, blow-by catch can system, more self promotion:wink:
8.bigger radiator, only if needed

Drive line
1.keep the 5 speed tranny, install short gears if you don't have them already
2.rear diff, either go Type R 4.23 with the extra pre-load spring or OG Giken 4.44 locker. The OSG is one of the nicest track mods I have done, makes the car soooo easy to throttle steer!
3.lighter clutch, Tilton carbon/carbon is the best out there, drops 26 lb. from the drive line, releases tons of power to the rear wheels!

Brakes
1.DUCTS to all 4 corners, remove the inner shields
2.slotted floating rotors all 4 corners
3.aggressive pads

Wheels
1.stock with race rubber

Body
1.ducted hood
2.splitter under front bumper, longer the better!
3.under tray for bumper and battery area
4.rear valance and diffuser
5.rear wing, not too aggressive because they really take lots of power to push through the air and high speed

Once you take the plunge and go with FI, a BBK, bigger wheels and tires will be in order. I would go to a good 6 or 7 point cage at the same time, tie the rear spring perches to the roll hoop, to the front sub frame by the dash.

I am happy to help if you have specific questions, PM me if you want.
Dave

 

[f1racr]

Dave, that's truly everything I was looking for and then some.

I certainly will be purchasing some of the items you mention when things kick off so I'll be in touch.

I'll drop you a PM so I can get some contact details from you so I can get in touch.

By BBK you guys mean Big Brake Kit right ?

I was thinking of Stoptech as I've got some on the GTR and they're awesome. We've put some on a mates Targa GTR and he's won the event for the last 2 years.

Anyone got any opinions on the best aftermarket brake kit if I feel the need ?

What about Superchargers ? Any well known workable combos ?

Also on the ECU front I'm thinking HKS FCON Pro as again I have one in the GTR and it's sooooo smooth and makes great power. Any comments for or against anything I've mentioned is much appreciated.

 

[robfenn]

Perhaps it would help if you could say what sort of environment the NSX will be racing in?

From my point of view, our NSX is in 30-40 min races which is pretty damn hard on the car. Consequently, we have spent that bit more on getting the best brakes and suspension possible. This has led to huge development cost which is where it tends to make much more sense to buy something like a 911 Porsche where modifications are all off the shelf.

 

[titaniumdave]

Dave, that's truly everything I was looking for and then some.

By BBK you guys mean Big Brake Kit right ?

I was thinking of Stoptech as I've got some on the GTR and they're awesome. We've put some on a mates Targa GTR and he's won the event for the last 2 years.

Anyone got any opinions on the best aftermarket brake kit if I feel the need ?

What about Superchargers ? Any well known workable combos ?

Also on the ECU front I'm thinking HKS FCON Pro as again I have one in the GTR and it's sooooo smooth and makes great power. Any comments for or against anything I've mentioned is much appreciated.

Happy to help!

BBK= Big Brake Kit

Most of the big name brands are good. Most important thing is to define where you want to end up with the car. So easy to overspend in one area and not make your goals in another. If you want endurance racing level brakes, your options are limited, the Brembo Racing brakes in this thread:
www.nsxprime.com/forums/showthread.php?t=95471
will work for you. Most folks don't need that much so the money is better spent in other places. The other down side on these calipers in no dust boots, so they are a bit fussier to live with.
Stoptech is working on a new line of forged calipers they will have out the end of this year, might be worth waiting for if you are committed to that brand. They will be smaller, lighter and stiffer!

Take a look at turbos for FI, not much development going on with SC right now. If Comptech gets going again, there are now good options with Shad's aftercooler for the high boost SC set ups.

The ECU choice is more about getting good tuning. The systems are pretty good for the complete stand alones, comes down to who can get the maps correct and fiddle with it to keep it running safe and powerfully.

 

[f1racr]

Perhaps it would help if you could say what sort of environment the NSX will be racing in?

From my point of view, our NSX is in 30-40 min races which is pretty damn hard on the car. Consequently, we have spent that bit more on getting the best brakes and suspension possible. This has led to huge development cost which is where it tends to make much more sense to buy something like a 911 Porsche where modifications are all off the shelf.

Hi there,

Yep as mentioned in the original postings, what I'm really after is using the vehicle for your normal track day events, so no more than say 10 laps at a time, but also longer events, say, 15-20 minute sprint races which I would like to run, and then the last event type which is our annual Targa road race.

Now I of course understand that I'll need to engineer the car for the worst of those 3, however the Targa isn't particularly about out and out speed, it's more of a fun event for me, so my plan is to engineer the car to last for those 15-20 minute sprint events and then running it for anything else should be a breeze.

Dave, I fancied a supercharger as it's something different and didn't want to have another turbo car with nothing below 3000rpm. Was hoping that some of the supercharger setups for the NSX might give it some low down grunt and let the engine natural character take care of the high stuff the same as my EP3 Civic........ is that not the case ???

I'd read somewhere of someone making a 3.5 litre engine which when combined with a low boost (4-5lb) supercharger was good for around 500hp.

Can't remember the website now, but I'll hunt it out again.

 

[docjohn]

For the 3.5 supercharged motor pm Chad at Driving ambitions.

 

[f1racr]

Huh........ just goes to show ya.

They're one of our customers (I work for Dynapack) ...... didn't even know !!

Looks like I've found my engine provider........it's all coming together.

Just on another angle...........any upsides / downsides to going 3.5 ? Worth it ? Best suited to NA or FI ? Interested in peoples comments.

 

[titaniumdave]

Huh........ just goes to show ya.

They're one of our customers (I work for Dynapack) ...... didn't even know !!

Looks like I've found my engine provider........it's all coming together.

Just on another angle...........any upsides / downsides to going 3.5 ? Worth it ? Best suited to NA or FI ? Interested in peoples comments.

The only down side tot he 3.5 L is cost...and delivery time...with 12 lb of boost the car drives like a V8...with 6 lb of boost it still pushes harder my 3.0 with 10 lb of boost!

Shad at Driving Ambition is the man!

 

[f1racr]

OK it's been a while since I last posted, but things are coming along nicely.

I just missed out on this donor car at auction.......

..... went for a song, but still, I'm bidding on a couple of other stock cars which might be better suited, at least I'll know what I'm getting I suppose, but that car had a fair few nice bits already and some of the body mods that I'd planned to do already so might have saved some time and money.

I've been talking to my tuner here that looks after my GTR and he's fairly comfortable with the concept of the NSX engine, although never worked on one, so I think we're going to look to a US builder, Driving Ambition potentially unless others tell me why not or who I should look to, to build a 3.5L unit which we'll supercharge, and then we'll go over it here rather than reinventing the wheel since you guys have a lot more exposure to these cars than we do down here.

One question though that came out of our discussions is what engine management do you guys run ? I currently use HKS FCON Pro in the GTR, and MOTEC in my other car, but wondered if there's a more suggested route for NSX's ?? Any sugggestions much appreciated.

 

[stuntman]

Both F-Con and Motec are great ECU options.

What was this car going to be built for again? Track days, regaional racing, time trials,...?

I would still look into using Brembo for your braking needs. As far as suspension goes, their are a few different options out for varying price ranges, but depending on the budget and intended use, any of these would be great options:

Moton 3-way Race coilovers
Moton 2-way Club Sports coilovers
KW Variant 3 2-way coilovers
Penske 2-way Race coilovers
Koni/Comptech 2-way coilovers

 

[f1racr]

Yeah car will be exclusively for track days, road racing and the like. Not interested in making too many compromises for road use.

From what you've written I'd assume the 3 way Moton's would be your choice then based on what I've stated ? Where can I look at these some more and get pricing ?

If you think the FCON will be a good fit then I'll go that route as my tuner is an HKS agent and I'll be trying to stick to that brand for other parts if I can, but suspension and brakes I'd rather get the best and HKS tend to just rebrand other people stuff in those area's anyhow.

Thanks heaps for your help and insight into this area, it's very helpful to us less enlightened people

 

[syam]

Yeah car will be exclusively for track days, road racing and the like. Not interested in making too many compromises for road use.

From what you've written I'd assume the 3 way Moton's would be your choice then based on what I've stated ? Where can I look at these some more and get pricing ?

If you think the FCON will be a good fit then I'll go that route as my tuner is an HKS agent and I'll be trying to stick to that brand for other parts if I can, but suspension and brakes I'd rather get the best and HKS tend to just rebrand other people stuff in those area's anyhow.

Thanks heaps for your help and insight into this area, it's very helpful to us less enlightened people

you can check out the prices of several suspension systems at Science of Speed's website. (www.scienceofspeed.com) the Moton 3 way adjustables are just about the best you can buy, but price again comes into the question. they also carry a few other very nice suspension packages.

also, to achieve the power goal you are after, a 3.5L stroker seems like a very good fit. add an intercooled supercharger system with that, and you'll have a beast. probably something like this: click

there are many very good engine management systems that can be used on the nsx. alot of people choose the AEM EMS, along with the F-Con system. As you know someone who knows the F-Con system, this may be the best choice.

keep us updated on the project as it looks like an awesome build.

 

[f1racr]

Some really interesting reading there........ thanks for the link.

I've been doing some more reading through posts as well and have another question.

Assuming that we're looking at about 500HP at the wheels then is the factory gearbox going to cope, short and long term ?

Any sequential options for the NSX ?

I think those Moton shock kits are pretty reasonably priced relative to what they are......... I'll have to do some more research, but at this point I think that part of the build is covered now