Horsepower - Page 2

JP · 08-05-03, 10:08 AM

[ QUOTE ]

JP, there is a production car that was originally purely designed for the road and has 600 bhp, weighs about 1 ton and has boot space for the golf bag plus comfortable seating for two passengers. McLaren F1. Yes please!

Malcolm

[/ QUOTE ]

If only I had the spare million! [img]/ubbthreads/images/graemlins/crazy.gif[/img]

Driveable and modern with 600HP. How's about a Brabus Merc. to tow the 40 to the track! [img]/ubbthreads/images/graemlins/grin.gif[/img] That's more like it, might look like a pimp though!

Regards,

J.P

JP · 08-05-03, 10:10 AM

Oh, almost forgot! I here that Dave Millam's funny car is very driveable with 2000HP!! [img]/ubbthreads/images/graemlins/wink.gif[/img] In a straight line of course!

J.P

Malcolm · 08-06-03, 05:22 AM

I think you will find that that car is his missus's car. He "just" polishes it for her! [img]/ubbthreads/images/graemlins/grin.gif[/img] I also thought it was about 2500 bhp but heck whats 500 bhp between friends?

However it does raise an interesting thought to me. I am a beleiver that the power loss through a tranny is a finite amount. I know I am in a minority on this forum with that one but are the guys who work on percentage losses telling me that Steph loses 400 bhp through tranny power drain? Or do they just adjust the percentage to suit?

Malcolm

Gary Gibbs · 08-06-03, 08:38 AM

I would guess on a 2000 HP car you would loose 300 - 400 HP through drivetrain losses. Just my opinion [img]/ubbthreads/images/graemlins/smile.gif[/img] It would be interesting to put his car on a chassis dyno as surely this amount of loss would be measureable.

Mark Worthington · 08-06-03, 09:41 AM

[ QUOTE ]
However it does raise an interesting thought to me. I am a beleiver that the power loss through a tranny is a finite amount. I know I am in a minority on this forum with that one but are the guys who work on percentage losses telling me that Steph loses 400 bhp through tranny power drain? Or do they just adjust the percentage to suit?

[/ QUOTE ]

I agree with you, Malcolm. Well, sort of. I agree with you that drivetrain losses are not a fixed percentage of crank hp, rather, the inertial losses are fixed, and the frictional losses will increase with applied torque, but at a rate that is nowhere near 15% of the crank hp.

Ron Earp · 08-06-03, 10:20 AM

I agree with this too. If it is a fixed percentage then the horsepower lost gets very high with high horsepower motors.

For example, if my 4.6L DOHC on 24 lbs of boost makes 760 hp at the crank with a 15% driveline loss then I'm losing 114 hp in the driveline and transmission.

One horsepower is 745 watts, so, we're losing 84930 watts on the way to the rear wheels. 1 W is 1 Joule/second. 84930 joules is a lot of energy and will generate a heck of a lot of heat.

Where does this heat go? If it is from friction then some fluid temperatures are going to get really hot.

Just looking for answers in an interesting discussion.

Ron

Veleno · 08-06-03, 06:42 PM

[ QUOTE ]
I just picked up Muscle Mustangs and Fast Fords (yes, good dyno articles every now and then). The 03 Cobra (4.6 DOHC, Eaton blower), with only some simple mods - pulley change, throttle body change, cats, and full exhaust with headers, was making 530hp and 600 lb/ft at the rear wheels. Good huh?

Not the focus of the article. The article was to highlight a Kenne Bell blower swap on the car for a screw type setup. Once done the car netted 708hp and 670 lb/ft. That is quite impressive for such a small mill and pushes the porky (3800 lbs) Mustang at 11.00 at 139.60 mph. These are all rear wheel numbers, not crank numbers. And, the supercharged motor has all the drivability that you'd ever want - low-end torque and horsepower - it isn't peaky at all, table like torque production.

Ron

[/ QUOTE ]

Ron, I read the same article..... It's so crazy.

I was planning to built a GT40 with a N/A 4.6 DOHC. I think I can push this engine between 550-600 hp at 7500 rpm (crank HP) with the help of a freak HP friend.

With Supercharger, you need to have to produce HP on lower RPM band to save the Supercharger and don't produce to much heat (correct me if I'm wrong).

I also like the thinking to have a 8000 rpm Red Line on my GT40 with a low torque at low RPM (easy for crusing on town).

Please, give me your comments.

Thanks

EG

Ron Earp · 08-06-03, 09:48 PM

I don't know if that motor is RPM limited due to piston speed, valve train, or blower speed. I suspect blower speed. I've used Eaton blowers before and they are limited to somewhere between 12000-18000 RPM. It depends on the model. That engine uses the 112 inch Eaton unit which is probably limited to around 12k (blower speed, not engine speed). These guys put smaller pullies on them to turn them faster and produce more boost. It might shorten the life, who really knows?

But, that wouldn't matter for you. If you want a blower and you want high RPM use can use a centrifugal blower like a Paxton, Powerdyne, ATI, etc. And mod motors really like these blowers! They are not positive displacement blowers so they don't make the power down low like the Eatons and screw types.

Better yet, if that is what your are after then turbocharge it, you'd be better off!

R

Knighton · 08-07-03, 01:05 AM

Is it possible to put a twin turbo on a 302 in an RF GT40? Is there enough room?

Does Gordon Levy turbo charge his engines?

Mark Worthington · 08-07-03, 02:36 AM

Gordon has not fitted a TT engine to a GT40. I think there would be room for the turbos, if you used small, efficient turbos like Garrett GT35s and had the manifolds and dumps custom made from 321 stainless. The problem would be finding a place to fit suitably sized intercoolers. Twin intercoolers could be fit up against the side scoops but they couldn't be too large.

Do a search on this tpic and you'll find pics of Tony Marsh's TT Rover VE setup. Tony was helped by his smaller engine and his use of the slightly larger Mk II rear clip. I'm also told there's a TT (GTD maybe?) running around somewhere in Australia.

Bill Bayard · 08-07-03, 06:20 AM

Mark,

Cos Sorgiovanni owns the TT GTD, in Australia.

GT40 NZ is offering a TT setup. Perhaps Dave Harvey could

enlighten us on how this task is accomplished, without

melting the rear clip! [img]/ubbthreads/images/graemlins/shocked.gif[/img]

Bill

LeGT40Mans · 08-07-03, 07:20 PM

HA HA! There is so much feedback, I don't have anything of much interest to write. . .

Realistically, I could care less how much horsepower a GT40 has. A GT40 is a GT40, and awesome no matter what drivetrain you have. But if it's fast and you can drive it without detaching your arms from their sockets-more power to you.

Brett James-McCall · 08-08-03, 09:13 AM

Here's a picture a friend sent of a 1300bhp Chevy from an Ultima.... its had to be detuned to 850 though as it keeps dismissing gearboxes!!!

Martin Weigold · 08-09-03, 02:55 PM

Scott

I just checked out the Roush site you mentioned because I am interested in going down this route. However, when I looked at the dyno sheet for the 402R it was inconsistent with the spec sheet. The spec sheet quoted 525 HP and 500 Ft/lb whereas the dyno sheet shows 500 HP and 475 Ft/lb.

Were you aware of this?

Also, do you know what the weight of the engine is?

Martin [img]/ubbthreads/images/graemlins/confused.gif[/img]

cos · 08-10-03, 02:43 AM

A few pictures of the car and engine.

cos · 08-10-03, 02:44 AM

.

cos · 08-10-03, 02:46 AM

,

cos · 08-10-03, 02:47 AM

..

Mark Worthington · 08-10-03, 03:10 AM

Cos, that is a sweet setup. Congratulations on an extremely well-done GTD. Care to tell us about your gearbox? Where do the intercoolers draw fressh air? How much horsepower does your engine make?

Nice to see you post here...I've heard about your car and have wanted to see it.

Ron Earp · 08-10-03, 08:15 AM

If any of you are into dynos and seeing what cars do on them you might want to check this out:

http://dynoperformance.com/index.php

It is a forum specifically for talking about engine output etc. Not bad really and there are a lot of those 4.6L DOHC Cobra motors (in the new GT40 soon) putting up some impressive numbers.

Ron