ITS TR8 Torque and Horsepower Numbers -- Dynojet

JeffYoung

New member
Since I firmly believe in full disclosure and since I am also fairly buzzed, I figured I would post my dyno results.

Car: 1980 Triumph TR8 ITS. Stock cam, compression, pistons. Headers. That's it (no emissions, etc.).

Stock numbers: 133 hp (crank), 170 torque (crank).

Dynojet: 159 hp (wheels), 188 torque (wheels).

Nice fat torque curve too.

So, significant gains simply from dichig emissions and working the exhaust a bit.

Meaning to me? Lots of cars with less hp turning faster laps than me. Gots to work on the driver, as the car appears to have seriously potentil when built to the max.
 
Good stuff, Jeff. Nice disclosure!

So, dreaming here...IF you went 40 over, got the compression right on the money, and a host of other little tweaks, you'd have another????

10? 15?

Wat does your car weigh?

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Jake Gulick
CarriageHouse Motorsports
ITA 57 RX-7
New England Region
[email protected]
 
Awesome! Throw some .40 over slugs in there, some well thought out head work (nice gains there), a custom (dyno tested) exhaust, hmmmm....I bet you could EASILY see 175 at the wheels and 190 ft/lbs...

What RPM range are we working in? I am assuming the 5700-5800 peak HP area?

NICE!

AB

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Andy Bettencourt
New England Region, R188967
ITA project SM
www.flatout-motorsports.com
 
Very nice results!!! I was suprised a bit that it was this strong but that is a good suprise.

I think there is around 25 more rear wheel hp in the engine, based on what I know of it and have seen on this engine. I think we can extract that much more out of it and hopefully shift the torque curve up 1000 RPM, but, once that is done I think all the hp/torque will have been had from the motor and it'll all be driver at that point.

Still, if the car had 185 rear wheel hp it'll certainly help a lot and at a weight of 26XX it'll be very competitive, especially on twisty tracks where the torque will help. I think aero will kill the 8 and my own JH on the straights, open cars are in no way nearly as aerodynamically clean as coupes.

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Ron
http://www.gt40s.com
Lotus Turbo Esprit
Ford Lightning
RF GT40 Replica
Jensen-Healey: IT prep progressing!
 
So let's say 180 RHHP and 195 ftlbs in a 10/10ths motor. At 2610, you have a SERIOUSLY fast car.

If you had to do it again, how about the coupe? Hardtop with revised cage?

Cool car.

AB

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Andy Bettencourt
New England Region, R188967
ITA project SM
www.flatout-motorsports.com
 
As it is it still gets SMOKED by the BMWs on the two straights at VIR. I've watched that happen myself, out of the corner very close but by the start of braking at the end of the straight the BMWs are 6-7 car lengths, easily and sometimes more, ahead of the little TR8. But, maybe more power here and a restrictor there will equalize things a little more.

R

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Ron
http://www.gt40s.com
Lotus Turbo Esprit
Ford Lightning
RF GT40 Replica
Jensen-Healey: IT prep progressing!
 
Originally posted by rlearp:
As it is it still gets SMOKED by the BMWs on the two straights at VIR. I've watched that happen myself, out of the corner very close but by the start of braking at the end of the straight the BMWs are 6-7 car lengths, easily and sometimes more, ahead of the little TR8. But, maybe more power here and a restrictor there will equalize things a little more.

R


...and getting off the corner better! How is the handling?

AB
 
Jake, weight on my car is 2560 and I have to run ballast to make it with a 180 lb driver (Andy the coupes are listed a bit heavier at 2610).

I too was surprised by the strength of the numbers. I told Ron before the run that I expected 160 at the crank, 140 or so at the wheels.

I guess we forget how smogged out and sloppy motors from the late 70s and early 80s were. Surprising that I picked up nearly 50 hp (that's over 30%) from exhaust and balance/blueprint, but maybe it shouldn't be. If you saw the emissions stuff on this car, you would have laughed. Air pumped via rails into the cylinder head. Air drawn of the manifold into the intake track. Air from the cylinder heads pushed into the carbs. Also, the stock manifolds were tight and the car had one cat and TWO mufflers on each pipe.

So maybe not so surprising, the gains.

Ron believes that ignition (the timing is moving around) and exhaust will get another 10-15 hp. Head work should give some, and you can go .020 over (the cylinders are too close together for .040) for a bit more (although the pistons are $1000!).

I suspect 180 at the wheels is possible, although I would not have thought it. Another big gain will be using the exhaust (Ron knows how to do this, I don't) tube length to move the peak torqu from 3000 to 4000 RPM. While the torque curve is fat, the peak is very low.

Andy, yes, if I had to do it over, I would have built a coupe. The problem is that there were only about 200 TR8 coupes made, and they are hard to find (but when you find them, they can be had for much cheaper than a convertible).

What's the rationale on not allowing a hardtop on a convertible in IT? Just wondering if there was any room for a change in the rules there, as switching everything over to a coupe body (if I could find one) would be a ton of work.

Thanks for the encouragement guys. This really reaffirmed for me that the driver is the slow part of the car STILL. I've got plenty of power as it is now that I'm not using as wellas I should.
 
Need to stop oogling this dyno plot and get back to work, BUT....

Andy, handling is decent. It's a live rear axle but the car is very wide for its wheelbase (which is short) and pretty stable. It used to just spin the wheels out of tight corners, but a Quaiffe cured that and netted me 2 seconds at VIR.

I've got some development work to do on the rear. I'm still running rubber bushings, and SPAX shocks. Revalved Konis would be a help and the spring rates are wrong (400 lbs, I've been told by others I should go a bit softer to get more grip).

Car will snap spin under power if you are not careful. That is the biggest limiting factor coming out of corners right now.
 
Why are the pistons so expensive? I thought the BL V-8 was the same Buick/Olds/Pontiac (all-aluminum) V-8 that was used in the early sixties cars. It was the same engine that was shortened to make the now famous Buick V-6, so wouldn't pistons be easy to find, and cheap, too?
 
Mark, good point. I just looked in the Victoria British catalog and those jokers want $1000 for the .020s. You are aboslutely right, the motor is the old Buick 215 (the Olds version is slightly different) that Rover bought from Buick in the mid 60s. Need to find .020 over Buick pistons, but might be hard to find them with the correct compression. The TR8 is I think THE lowest compression version of the 215 ever made (8.15 or something to 1).
 
Can't you just have some whittled out of a lump of aluminum to the same design and dimensions - plus .020 - for a lot less dough?

K
 
Don't know, I'm knew to this stuff. Can some one custom make you pistons to your specs? For less than $1000? I guess I just figured that it would be more than buying off the shelf.

Did a bit of on-line searching. Only Buick 215 pistons available are 8.8 or 9.6 compression. ILLEGAL....durn, cause they are cheap.
 
Yep, they can. Try JE Pistons.

Also, you could get the 8.8 pistons and have a machinist take some off to get it back down. No big deal in some cases, depending on the design. Still I bet cheaper than $1000.

Ron

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Ron
http://www.gt40s.com
Lotus Turbo Esprit
Ford Lightning
RF GT40 Replica
Jensen-Healey: IT prep progressing!
 
As a fellow TR8 racer in the midwest, you have to love torque. It helps makes up for its handling and braking. Give me v8 torque anyday, blast to race.

I also wouldn't be so quick to take the coupe over the convert. Having both, I find I like the convert a little more. Some of the reasons are; it is 50lbs lighter, which is not much, but think of where the weight is, all above your shoulders. Also the car was originaly designed to be a convert, not a coupe. Triumph built the car with side and frame stiffeners that the coupe do not have. Also, a point that I like is that there is far more visability than the coupe offers. If you have ever been in a coupe with a cage, it has poor side and rear visability. However, it does come down to what is available, the coupe we have have been a racecar for 25 years from the showroom. I don't think you wouold find a true TR8 coupe anymore that would be good for racing. If it is in good shape, they could be worth something.

It was good to hear those numbers Jeff. Also try over seas to get pistons, should be cheaper
 
Jeff sounds like you have done some great work with that car-those are good numbers. You should try 300 pound or less springs in the rear and do not run a rear bar if you want it more predictable. If you deceide to go with the pistons, drop me a line or see me at the track and I can order them at cost (lots of years racing production Triumphs) from VB.

Steve Eckerich
ITS 18 Speedsource RX7
Southeast
 
All this talk about TR8s and especially coupes made me pull out this old photo.

The very first TR8 in this country (of any sort, race or otherwise) in it's first appearance - 6 hours of Watkins Glen, 1979.

TR8.jpg



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George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com
 
The Group 44 cars (nos. 4 and 44) were beautiful cars, and overdogs. SCCA loaded them up with weight after they dominated the 79 season, so Tullius went to IMSA. Tullius loved the car, and his mechanic, Lanky Foushee, says it saw 195 on the banks at Daytona.

Check out www.lanocharacing.com. Lots of Group 44 (and Ken Slagle, who won C Prod in a convertible in 82 as a privateer) pics and information. Tim Lanocha actually got his hands on the old Group 44 fiberglass molds and can make you a replica of the car pictured above if you have the desire and the dollars.

George, one clarification on TR8 lore. The 7 was originally designed to house the 3.5 liter Rover V8 and the TR8 was originally supposed to debut shortly after the 7 (and Triumph might still be with us if it had). However, the Rover V8 was in short supply in 75 and 76, and that delayed the launch.

About 50 pre-production TR8 coupes, almost all automatics and all with no markings to identify them as something other than a 90 hp TR7 came to the states in 1978, were tested by dealers and sold to the public. Those were the "first" TR8s. Buffum may have had his TR8 (I think it was actually called a TR7V8 at the time, like the English rally cars) rallying in 78 as well.

But, you are correct, the Tullius Group 44 8s came to the states and raced in 79 before the "official" launch of the TR8 in 1980.

Andy Doyle's dad Morey (Andy posted above as TRD77) actually bought a 1980 TR8 coupe off the showroom floor and went showroom stock racing with it. In the mid-80s, Ted Schumacher in Ohio got the car classed in Improved Touring S (there was resistance because of the V8) and Morey has a number of ITS regional wins over the years. Ted had a fair amount of success with teh car in the Playboy Endurance series. I still rely on him for parts and racing advice. He's making me some new headers over the off-season, and is a great guy to talk to for racing lore.

Andy and Morey still run 8s (I think they, and myself, are the only ones left with Kischbach's car in the NEDiv parked, and John Roper in Louisiana parked), and they run them competively in the MidWest. Go look up results at Gateway, where they win, or in large (15 car plus) fields at Mid-Ohio, where they run top-5. Amazing what they get out of the car. Especially since Andy is right, the torque is great, but it masks serious weakness in the brakes.

Steve, thanks for the words of encouragement. Lots of work left to do, a lot of it on the driver as the results Andy and Morey post show my car is far more capable than the driver right now.

I have 300 and 250 lb springs on order and will try those at the VIR test day in March. You would also disconnect the rear bar?

Thanks on the pistons as well. I will catch up with you about that. I'm going to run this motor till it dies, and then build a 10/10 motor out of an old block I have. But if I can get the pistons cheap now through you, I will, and then store them. Maybe then I can stay out of your way...lol...that black RX7 looks nice going by. You were hauling it at Roebling...

Thanks agian guys.

Jeff
 
Originally posted by JeffYoung:
About 50 pre-production TR8 coupes, almost all automatics and all with no markings to identify them as something other than a 90 hp TR7 came to the states in 1978, were tested by dealers and sold to the public. Those were the "first" TR8s. Buffum may have had his TR8 (I think it was actually called a TR7V8 at the time, like the English rally cars) rallying in 78 as well.

That's interesting. That weekend they made a big deal of this being the very first on US soil. Regardless, this car made me a life-long fan of the TR8. The car ran flawlessly and beat many bigger and faster cars. I always thought it would be fun to have one. This car made me a real fan of the coupe which is quite rare compared with the convertable.


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George Roffe
Houston, TX
84 944 ITS car under construction
92 ITS Sentra SE-R occasionally borrowed
http://www.nissport.com
 
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