Lotus Esprit vs. Honda NSX

[scirocco]

Originally posted by Octagon
A wonderfully nimble chassis is a lot of fun in constantly sweeping corners, but a gutless engine saps all the fun away once you come to that first 2nd gear hairpin. Torque brings a car to life, leaping out of the corners and throwing the tail around with glorious aplomb.

But then, I've also driven a 1700lb car powered by an 880hp, 950lb ft of torque methanol burning big block Chevy, running direct drive back to a Halibrand quick change rear axle. Just about anything seems unresponsive after hot lapping an ISMA Supermodified.



That's the 1981 Showcar chassis supermodified I tested. It was owned by the late Dion Parish, my friend and would-be car owner had he not died testing his new car at Kalamazoo Speedway.

While I'm here, holy crap. You are so lucky. How many G's on acceleration would you fathom there are in that thing? I mean really, 880 hp. That is amazing for such a light car.

[jaydm180sx]

Originally posted by scirocco
okay i will send it to your e mail.. what is it?

go to my profile

[scirocco]

okay i have tried sending it to myself and it keeps saying "retry network?" Anybody got a cell phone that I can send it to? I got to go now I'm off to the races so to speak but I'll make sure to be in later. Bye for now.

[scirocco]

Originally posted by mr2
The Elise has a Lotus tuned ECU for the GTS engine and its not all of the parts in the Engine is stock and I think that the gear ratio is turned differently.

The reason why the elise weights in around 1600-1800lbs is because of its chasis. It's not a standard steel chassis as like the Esprit except that it is zinc coated.

The Elise chassis is a remarkable piece of engineering. Made from extruded aluminium glued and riveted together to form an immensly stiff and light weight platform on which to built an open top car. The bare chassis weighs about 70kg and the rivets are only there to prevent peeling in the event of a crash.

It only weighs 1600 lbs?! I thought it weighed around 2,000 which is light anyways. Wow maybe I should ditch my scirocco and get me one of those fine machines. Imagine what some money could do for one of those! They are very aerodynamic as well.

[Octagon]

To answer your question, scirocco, not as many as you'd think.

Since they're direct drive, supermodifieds are push started by jeeps. The process goes pretty much like this.

1 - turn on the fuel pump.
2 - engage the "in-out" box, basically a coupler that engages the driveshaft to the crankshaft.
3 - get off brakes as jeep starts pushing.
4 - watch oil pressure gauge.
5 - once oil pressure gauge reads normal running levels, flip the kill switch off on the magneto and hold on as the engine fires and attempts to rattle the car to pieces.

The cars run at about 30-45mph at idle (depending on gearing for the track). The average speed for a lap is usually between 140-160mph. A good lap time at a fast 1/2mile oval like Toledo or Mansfield Speedway is about 14.3seconds or less. The car is usually running around 125-140 in the turns and accelerates up to 165-180 on the straights.

I'd guess, though, 2+ g's accelerative, and a bit more decelerative.

[Octagon]

I also might as well tell you that the car I drove is a mid-pack at best car for ISMA. The real top dog car is the Clyde Booth built #61 driven by Mike Ordway. They're more like 950hp and the chassis is much more refined with an Indy-style pullrod IFS as opposed to the torsion bar solid axle front of the Showcar.



Good picture of Ordway battling with "Liquid" Lou Cicconi at Toledo. They're going about 150+mph in this shot coming through turns 3 & 4. The speed of the cars is 1/3rd engine, 1/3rd advanced chassis and aerodynamics, and 1/3rd these monster Hoosier tires.

[scirocco]

Actually, I was thinking 2 or maybe less. I noticed that the tires aren't really big enough to handle that horsepower through the entire rev band and I would assume that that is why so much torque is desirable through the rev band

[Parry]

Originally posted by scirocco
okay i have tried sending it to myself and it keeps saying "retry network?" Anybody got a cell phone that I can send it to? I got to go now I'm off to the races so to speak but I'll make sure to be in later. Bye for now.

What you need to do is go get a disposable camera. Burn the entire roll of film taking pictures of the car. I specificly want to see the shift assembly/tranny, rear diff mount, rear suspension, engine mounts, transfer case placement, and front and rear axles spindles controll arms, the steering rack, and a pic of you smoking the rear tires. I'd also like a picture of you standing next to it if you could. Hold up a sign that says "PARRY SUCKS" for me, please. When you are done get it developed, and get a picture CD so that you can get them onto your computer and send them to me.

Anyways, I still think you are a liar. Go spend 10 bucks on some pictures and prove me wrong and I will praise you as one of the most innovative and out of the box VW builders ever. If you were to send those pictures to magazines I 100% guarentee they will be all over that car.


Slightly more relevent, how tight do they wind up those motors Octagon? What's the rear end gearing like?

[Octagon]

Well, I've seen gears as steep as 4:30's for tracks like Star (which is a 1/4mile bullring) but more common is something along the lines of between a 3:73 to 4:10 for the more common 3/8ths and 1/2's like Kawartha and Sandusky.

The layout of the track also tends to determine what gears are run. Sandusky is a "little 1/2" which means it's a 1/2mile measured around the outer perimeter of the track. It's also a "paper clip" layout with long straights and tight corners. A steeper gear, less downforce on the bodywork, and more less resistance in the air strut on the top wing (the top wings are hinged so that they flatten out on the straightaways for less drag, and then pop back up at an angle in the corners for more downforce) are run at a track like Sandusky. Mansfield Motorsports Speedway, on the other hand, is a "big 1/2" - measured along the inside edge of the track - and has short straights and sweeping corners. The supers spend more time on the gas there, so more aero is needed for more grip and shallower gears are run for more top end.

A good supermodified engine (which, by the way, is a 468ci Chevy big block, iron block, iron heads, running mechanical fuel injection and methanol) will make good power up to 7200rpm. However, the most potent supermodified engines were built by Kevin Enders for RaceRace America, a team my father did PR work for. They were installed in a pair of chassis (1996 Bodnars) that I got the oppurtunity to assist in designing. The Kevin Enders engines used a flat crank and (instead of a stroker crank in a 454ci block) were bored out 427's.

They'd wind all the way up to 8500rpm without valve float and still be putting out monstrous power.

[Parry]

Star Speedway in NH? That's right down the road from me.

For those of you who don't know, turning motors like that to 8500 is wrapping them very tight to say the least .


It's interesting that they apear to be running ITB's. What does the torque curve look like? Where is peak torque?

[Octagon]

Well the torque curve is broad and meaty from idle upwards - natch for a big block like this - except for the aforementioned Enders engines which had a bit of a flat spot until 2200rpm.

Peak torque is usually between 4500-5200, and is well into the 900+ range. Very gutsy engines and there's very little driveline loss.

And Parry, you are so 'effin lucky to be right down the road from Star. It's home to one of the Triple Crown races of the supermodified world - The Star Classic. You missed it this year - it was on September 11th - but it's an annual 200lap feature at the Star 1/4mile that's a real test of a supermod's handling and a driver's patience. The master of Star is Pelham, New Hampshire's Russ Wood. Wood is a 5 time Star Classic winner, as well as the all time winningest driver in ISMA competition alongside 6 championships.



Here's Russ taking the checkers at Star this year. Notice the odd stance of his car, the way the tail is picked up while the wing is flattened. This is the way the chassis his team - Dunigan Racing - work. The Allegresso-Bartel chassis has an odd cantilever mechanism to its solid axle rear suspension that lifts the tail as the wing flattens so that air can flow more smoothly along the ground effects package and through NACA ducts on the car's underside that feed oil coolers. When the wing pops up going into the corner, the tail slaps down to load the rear tires and get them to dig in.

This chassis concept has worked for the Allegresso-Bartel chassis supermodifieds since Paul Dunigan had the first one built in 1988.

[Parry]

Hrm. The ITB's are fairly long, but I sorta expected peak torque to be a bit higher. With dispacement and compression like that you make power left right and center though.

I don't usually get down to Star. I am lucky though...i'm 15 minutes from New England Dragway, probably 20 from Star, an hour and a half from the white mountains (kancamangus, etc), 15 from the beach, and I can park my car on the front lawn with the keys in it and the house unlocked and sleep soundly. Can't crap on that.

[Octagon]

Heh, those aren't throttle bodies you're looking at, they're just the velocity stacks. The butterflies are down about two inches from where the chrome ends.

Here's a typical setup that would be used on a supermod.

[Parry]

No, I realize that, but overall intake leangth effects peak torque placement. That's why I was curious.

[Octagon]

Very true, the trumpet length makes a big difference, that's why teams keep a bunch of stacks of different lengths on hand. You'll often see a lot of varying height stacks on the same engine when one cylinder is running lean or rich.

Good that you're curious about these beasts. Supermods are an endangered species. Because they're so highly specialized and because there's no such thing as a mass-produced chassis in supermod racing, it's a very expensive form of racing to get into. The men who campaign the cars do it out of love for the cars and love for the thrill of competition. Between the MSA (Midwest Supermodified Association based out of Ohio), the weekly 350 Super series at Star (like I said, lucky), the weekly non-wing series at Oswego, and ISMA, there's only about 40-50 cars on the whole East Coast in active competition.

Couple that with the Supermodified Racing League and Englewood Racing Association on the West Coast, and there's maybe a grand total of 80-90 competitive supermodifieds in the country. Factor in that none of the organizations have completely homogenous rulebooks (ISMA and MSA are the most similar, but the MSA has no ci limit and allows small blocks and non Chevy engines, Oswego runs without wings, Star runs carbureted 350's, and the West Coast cars are totally screwy with more offset, smaller engines, no independent suspensions in the SRL, and fixed wings) and you have the exact reason why the supermod is dying slowly.

Anymore fans we can bring in are welcome to enjoy the most exciting racing on asphalt. There's nothing like that moment when they drop the green on the feature field and the whole ground shakes as 25 of the Offset Outlaws roar down the front straight.