S2000 Reborn for Racing
Joined: Oct 2000
Posts: 17,288
Likes: 39
From: Nashville
Wish I could find someone to sell me a wrecked S2000 for $4500. 
GREAT CAR GARETH!!! We do need more pics and more details on how you got the weight sooo low. Plus I think I remember you saying about a $25k spending limit.?
Scot
GREAT CAR GARETH!!! We do need more pics and more details on how you got the weight sooo low. Plus I think I remember you saying about a $25k spending limit.?
Scot
Joined: Oct 2000
Posts: 176
Likes: 1
From: Charlotte, NC
Holy $#*K! Can someone do some number crunching based on the power to weight ratio...i'm curious how quickly that thing will accelerate. I think we might be talkin ferrari territory here. 
keep in mind that if he is modding the engine it will be even faster! Double
keep in mind that if he is modding the engine it will be even faster! Double
Registered User
Joined: Feb 2001
Posts: 2,895
Likes: 1
From: You wish
The S2000 engine is about as close as you can get to a 2 liter BTCC engine - from a factory at least. It has excellent cylinder head design and bottom end geometry. Also, BTCC cars are limited to only 8500 rpm, so _theoretically_ the S2000 mill, if allowed to rev and properly modified, has more power potential.
Even in endurance trim, there should be little issue with getting 300 hp normally aspirated from the F20C. There are lots of things that can be improved:
1. More compression - depending on the series regs on fuel this could add a lot of power. With 100 Octane (R+M/2 the american way) you could easily run 13:1 compression, which would be good for a 2-4% power increase. Even with less stout fuel, you should still be able to run 12-12.5:1 with a good bit of headwork.
2. Camshafts - those who think the F20C is maxed haven't played with many other DOHC VTEC engines. The F20C's output is tame compared to big cammed B18Cs. There is easily another 15-30 hp in the camshafts depending on how much bottom end you're willing to sacrifice (the small lobes have to be made bigger too to avoid a midrange hole - but 15hp wouldn't cost you anything and would be streetable).
3. Cylinder head work - It's a good factory design but hand work (or proper CNC porting) always is good for a few hp. A good porter will be able to extract at least 10 hp more and perhaps as much as 20 hp with enough R&D.
4. Intake manifold - toss it for individual throttle bodies, or at least make the plenum bigger. 5-25 hp depending.
I'm curious to see if I've mapped out what Gareth has already done :-)
Of course, all this will require good tuning, etc., but it can be done. As proof, I would point out the numerous B18C Integras running around today, on the street, passing emissions, producing 200-210 wheel hp from 1.8 liters. The F20C has 11% more displacement, much less valvetrain friction (rollers instead of sliders), less bottom end loss (better rod ratio), bigger bore and valves (more flow), etc. Simply on displacement alone you'd expect to be able to get 230 wheel hp. All told, if you were really serious, 300-330 crank hp at 9000-9500 rpm should be doable. On the street, 270-280 is a very reasonable goal, probably achievable just with cams/headwork and maybe an intake manifold.
As for calcs, if the car comes in at a pessimistic 1800 lbs with a full load of fuel and driver, he should have a p/w ratio between 6 and 7:1 depending on output. By comparison, a Dodge Viper with driver has a p/w ratio of about 7.5:1, a 360 Modena is around 8:1 and a 911 Turbo is at 8:1. Even your typical 600 cc sportbike these days is only around 5:1 with a typical rider. Should be a quick car.
UL
Even in endurance trim, there should be little issue with getting 300 hp normally aspirated from the F20C. There are lots of things that can be improved:
1. More compression - depending on the series regs on fuel this could add a lot of power. With 100 Octane (R+M/2 the american way) you could easily run 13:1 compression, which would be good for a 2-4% power increase. Even with less stout fuel, you should still be able to run 12-12.5:1 with a good bit of headwork.
2. Camshafts - those who think the F20C is maxed haven't played with many other DOHC VTEC engines. The F20C's output is tame compared to big cammed B18Cs. There is easily another 15-30 hp in the camshafts depending on how much bottom end you're willing to sacrifice (the small lobes have to be made bigger too to avoid a midrange hole - but 15hp wouldn't cost you anything and would be streetable).
3. Cylinder head work - It's a good factory design but hand work (or proper CNC porting) always is good for a few hp. A good porter will be able to extract at least 10 hp more and perhaps as much as 20 hp with enough R&D.
4. Intake manifold - toss it for individual throttle bodies, or at least make the plenum bigger. 5-25 hp depending.
I'm curious to see if I've mapped out what Gareth has already done :-)
Of course, all this will require good tuning, etc., but it can be done. As proof, I would point out the numerous B18C Integras running around today, on the street, passing emissions, producing 200-210 wheel hp from 1.8 liters. The F20C has 11% more displacement, much less valvetrain friction (rollers instead of sliders), less bottom end loss (better rod ratio), bigger bore and valves (more flow), etc. Simply on displacement alone you'd expect to be able to get 230 wheel hp. All told, if you were really serious, 300-330 crank hp at 9000-9500 rpm should be doable. On the street, 270-280 is a very reasonable goal, probably achievable just with cams/headwork and maybe an intake manifold.
As for calcs, if the car comes in at a pessimistic 1800 lbs with a full load of fuel and driver, he should have a p/w ratio between 6 and 7:1 depending on output. By comparison, a Dodge Viper with driver has a p/w ratio of about 7.5:1, a 360 Modena is around 8:1 and a 911 Turbo is at 8:1. Even your typical 600 cc sportbike these days is only around 5:1 with a typical rider. Should be a quick car.
UL
Registered User
Joined: Oct 2000
Posts: 1,445
Likes: 0
From: Chicago
Great post UL... I've had very similar thoughts about the F20c's potential, but obviously in stock-class autocrossing I can't change anything on the engine. It will certainly be interesting to see what type of output Gareth's engine will attain.
On a seperate note, I'm glad to see that I'm not the only one drawing comparisons between our engine and the BTCC mills. With the Mugen exhaust our sound is even reminiscent of these racing machines. Whenever anyone 'doubts' the Stook's output I just bring up the BTCC rules and remind them that they are getting 330hp from a 2.0l with an 8500rpm rev limit!
Once again, great post UL... now Gareth - Let's see some specs!
On a seperate note, I'm glad to see that I'm not the only one drawing comparisons between our engine and the BTCC mills. With the Mugen exhaust our sound is even reminiscent of these racing machines. Whenever anyone 'doubts' the Stook's output I just bring up the BTCC rules and remind them that they are getting 330hp from a 2.0l with an 8500rpm rev limit!
Once again, great post UL... now Gareth - Let's see some specs!
Moderator
Joined: Oct 2000
Posts: 12,904
Likes: 93
From: Big Box suburb, IL
Didn't someone on this board last year issue a challenge as pertaining to the 'maximum' modification done to the engine while only seeing end results of minimally increased output without going with forced induction?
If I remember correctly the challenge was to squeeze out another 50 or so horses out of the engine. Anyway, my point is to find out who he is/was, and what are his thoughts on this thread?
If I remember correctly the challenge was to squeeze out another 50 or so horses out of the engine. Anyway, my point is to find out who he is/was, and what are his thoughts on this thread?
Thread Starter
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Joined: Jan 2001
Posts: 44
Likes: 0
Sorry for the delay, timezone stuff.
Wheels from Dymag -thru Raven Automotive, there Web site is down due to a ISP going bust, try http://www.ravenmotorsport.co.uk/
They sorted offsets etc
Engine Wise for Endurance we beleive 320BHP is the best we could acheive, the concern is movement of the Wet liners in the block, UL knows his stuff and has the engine mods spot on.
The GT web site is http://www.powertour.co.uk
One site to cruise http://ukmotorsport.com/ great links to
everyone who is doing something !!
Did you know you could get Titanium conrods thanks F1 and Indy !!
Funcar - yes we have a night race this year.
Weight loss - well apart from me down the gym every day since new year = 14lbs
From what I have seen Honda deliberately built weight into the car or did not care or for safety reasons. But the subframes are massive and very heavy, the doors have 2 iron bars called side inpact things, must have been 3/4 of the door weight. Wiring loom is massive. Boot etc
Plus all the usual seats,carpets,aircon,etc etc.
Anyway a rear wing is needed, front splitter, carbon fibre doors,body panels and boot need to be costed.
After the start of the season I will do a web site with shots of the roll cage, brakes, suspension, when we have to reveal what we have.
On the power to weight a 2litre car can weigh 700Kg anything else
So the TVR speed 6 weights 1000Kg and has 400Bhp or 0.4
If we get 300BHP and weight 800Kg = 0.375
Plus we should do corners better
Another pic
Wheels from Dymag -thru Raven Automotive, there Web site is down due to a ISP going bust, try http://www.ravenmotorsport.co.uk/
They sorted offsets etc
Engine Wise for Endurance we beleive 320BHP is the best we could acheive, the concern is movement of the Wet liners in the block, UL knows his stuff and has the engine mods spot on.
The GT web site is http://www.powertour.co.uk
One site to cruise http://ukmotorsport.com/ great links to
everyone who is doing something !!
Did you know you could get Titanium conrods thanks F1 and Indy !!
Funcar - yes we have a night race this year.
Weight loss - well apart from me down the gym every day since new year = 14lbs
From what I have seen Honda deliberately built weight into the car or did not care or for safety reasons. But the subframes are massive and very heavy, the doors have 2 iron bars called side inpact things, must have been 3/4 of the door weight. Wiring loom is massive. Boot etc
Plus all the usual seats,carpets,aircon,etc etc.
Anyway a rear wing is needed, front splitter, carbon fibre doors,body panels and boot need to be costed.
After the start of the season I will do a web site with shots of the roll cage, brakes, suspension, when we have to reveal what we have.
On the power to weight a 2litre car can weigh 700Kg anything else
So the TVR speed 6 weights 1000Kg and has 400Bhp or 0.4
If we get 300BHP and weight 800Kg = 0.375
Plus we should do corners better
Another pic