I just got back from the dyno with the blue RF. We dynoed at 483hp and 435lbft of torque. On the drive home by the top of the freeway onramp I hit 140 and it was pulling so hard. I love this car. I can hardly wait to run it at Willow Springs at the end of the month.
holy Spit
- Thread starter Gordon Levy
- Start date
The engine is a 342 stroker w/ a custom designed cam. it also has the 8 barrel MoTeC injection. If I had the larger throdel bodies it would have made over 500hp. when I hit 140 I was still in 4th with alot of revs to go. I think this car would top out at about 190mph. The 180 degree exhaust makes the car sound like a 6.0 litre F1 car, just awsome.
[ October 03, 2001: Message edited by: Gordon Levy ]
[ October 03, 2001: Message edited by: Gordon Levy ]
G
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Hey Gordon, I would like to know more about that cam. I have a 347 with Holley (same as Brodix) heads that have been worked. The springs and retainers have also been changed to deal with the cam. I have the same induction and induction system that you have on the blue car. My cam is a special design for independent runner FI with a goal of 10 inches of vacum at idle. This is so that MAP sensing can be used instead of throttle position only. The roller cam specs are .539/227 Intake and .565/236 exhaust Lobe center is 110 degrees. I worked with Ted Iskenderian to come up with this. What do you think?
G
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OOps, I meant to say same induction and ignition system from Roaring forties. Along with the Motec M48 computer.
My cam is a bit more agressive than yours and will rev to 7000. The cam you have will work good and will probably be within 30hp of the engine I have here.
Ron Earp
Admin
Hey Gordon,
What correction factor did you use from the rear wheel dyno to get the flywheel numbers?
Bob, you'll probably get similar torque at a lower RPM than Gordon is getting. Power may be down a little too, but I think it will be very close if the heads will flow well. I cannot remember comparisons I've read of the Holley heads, but I know the AFRs are tops for SBs.
Are the RF Tbodies 48mm?
Ron
What correction factor did you use from the rear wheel dyno to get the flywheel numbers?
Bob, you'll probably get similar torque at a lower RPM than Gordon is getting. Power may be down a little too, but I think it will be very close if the heads will flow well. I cannot remember comparisons I've read of the Holley heads, but I know the AFRs are tops for SBs.
Are the RF Tbodies 48mm?
Ron
Ron Earp
Admin
My experience has been that 0.7 for a correction factor is too high. With this number you're assuming a 30% drivetrain loss, seems to be a bit too much. I'd estimate a loss of around 17-22%, or a correction factor of about 0.8.
At least that is what is always comes out to be when I've run cars on the dynos. This would make your numbers a little lower, but numbers don't matter at all - its what happens on the track. And that motor sounds like it has plently of go for the road course, looking forward to reports. Have you run it in the quarter yet?
I also found the Victor Jrs to be pretty good on the upper range when they're ported well and have a high flowing intake to match.
Ron
At least that is what is always comes out to be when I've run cars on the dynos. This would make your numbers a little lower, but numbers don't matter at all - its what happens on the track. And that motor sounds like it has plently of go for the road course, looking forward to reports. Have you run it in the quarter yet?
I also found the Victor Jrs to be pretty good on the upper range when they're ported well and have a high flowing intake to match.
Ron
G
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I don't know much about the Holley heads. I bought an engine out of a totaled Mustang. Just before totaling the car, the owner installed the full Holley System Max kit with Ford MotorSport roller rockers and push rods. I bought the entire engine for $1,000. After I sold the Holley intake, cam, crank, rods, a/c compressor and all the other junk I ended up with a block and heads for less than nothing. My engine builder really likes the Holley Heads which are exactly the same as Brodix who makes them for Holley. I don't know if I will get every last bit of potential power, but I don't really care. I know it will be a thrilling ride. I highly recomend FREE Holley aluminum heads to anyone who has a similar opportunity.
Ron, In flow tests we find that the Victor Jrs will build more top end hp but the AFR's are a little better in the midrange. I think we were using a .7 correction factor. I sent Robert one of these engines and he is using the 52mm t-bodies. He should be able to pull about 40 more hp than we did.
[ October 04, 2001: Message edited by: Gordon Levy ]
[ October 04, 2001: Message edited by: Gordon Levy ]
pump premium. we are only using 10:1 compression.
Ron Earp
Admin
I think those heads flow good numbers. If I remember right, when dynoed against some of the other heads they came out to be good torque producing heads with a wide RPM range. Should be real nice for the car and very drivable. You can probably find out on the Corral, those guys always have the skinny on parts. Those heads cost over $1000 bucks, and you got them free.?!
R
R
It sounds like I might have to make a trip to Willow Srings. I would really love to see that RFGT40 with Gordon behind the wheel. If anyone can get the most out of this car it will be Gordon. I still think that the stock 302 that was in it before was quick enough for me. But I know my limitations. It's so hard for me to imagine that car being faster than when I rode in it with the 302.
I never seen a guy that gets this funny looking smile on his face when he talks fast like Gordon does.
Hersh
I never seen a guy that gets this funny looking smile on his face when he talks fast like Gordon does.
Hersh
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Gordon,
You've had lots of experience with "roadsters" (Cobra replicas ... for those that don't read Cobra Forum or the like) ... how does the GT40 compare in performance with a Cobra of similar horsepower and torque?
How about a comparison between them for us who really want to know what this is going to be like when its done?
Thanks!
You've had lots of experience with "roadsters" (Cobra replicas ... for those that don't read Cobra Forum or the like) ... how does the GT40 compare in performance with a Cobra of similar horsepower and torque?
How about a comparison between them for us who really want to know what this is going to be like when its done?
Thanks!
The biggest difference between the two is, the roadster moves around alot more than the 40. It also has a high sinsation of speed than the 40. The 40 is mush smoother, it accelerates much faster at over 100 than the roadster and is much smoother because of the aerodynamics. It is more comfortable in the 40 at 150mph thn the roadster. It's hard to tell how fast you are really going in the 40 unless you look at the speedo. or notice how fast you are passing everything around you. I love driving both, but they are two completely different cars.
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