justaguy

Wow! That fugly thing was at Laguna the time I was there I had no Idea it had that kind of power. It broke I just thought it was obnoxious. I should have looked closer.

GregBBRD

I wonder how long this would live on a racetrack?

A grand a minute?

dprantl

I really would like to see. As long as the intake temps can be kept to a reasonable level and crankcase breathing is sorted (), it should be as reliable as NA. There are other race cars in similar classes to race 928's that have forced induction. A 500rwhp 5.0 liter 928 should be just as reliable as a 250rwhp 2.5 liter 944 with both having FI (not accounting for the 928's faster speed around the track due to the extra power, that is a separate discussion); the 928's crank will still be yawning at double the stress.

Dan
'91 928GT S/C 475hp/460lb.ft

justaguy

A grand a minute?"
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That seems about right. People don't seem to realize how extreme door to door racing actually is. Like I said I can cruise around all day city or high way with no heating problems. I can even drive it on track at about 80%. But I only can race about 3-4 laps before it pukes. Bigger rads with better air flow would probabaly cure the issue. But with a Supercharger you have a whole other system that can potentially fail.

This car was originally built for Open Road Racing and the supercharger would probably work well in that application ( until it throws a belt)
The continous on and off the throttle in road racing is a problem for supercharged engines. My buddy tried to race a chevy cobalt ss with a supercharger and he experienced the same issues as me. The thing puked a few laps after the green flag dropped. A system designed by a team of engineers at GM was not up to the task of Road Racing. I was feeling frustrated with my overheating issues until I saw Mike have the same issue with a factory system. At that point I realized trying to race a supercharged 928 was a futile exercise. Sure I've go 550 hp and it looks good on paper but what's the point if I can't finish a race.

I would like to get a supercharged Z 06 on track on a hot day and see if the cooling system on that thing is up to the task. It may be but I doubt it.

mark kibort

500hp breaks transmissions. not immediately, but they do break. also clutches as i have heard.

400rwhp is achievable, that will get you under 2min, but nice luck trying to do it for under $10k. your smokin crack to think any car under 10k can run that fast. not that it isnt possible, but not probable!

plan on $20k in anything you want to drive out there. bmw , porsche, mustang, etc. $20k to break 2min. if its been done for cheaper, let me know

what do you think it takes to break 1:37 at Laguna seca? Ive run 1:36.1 in the holbert car and the remake of the Holbert car, and i can almost gurantee, mine is the cheapest car out there runninng that fast.

mark kibort

yeah, thats what im saying. you understand the relationship between power and acceleration, drag, speed, etc?? its a cubed factor. double the speed, 8x the power....... that kind of thing. go to a simple drag calculator, and see what it takes to get a car to go from a 1/4mile top speed of 120 and then a car that does 140. look at the power it takes. then, get back to me!

Brian is smokin crack too. he is not hitting 120 down the straight at thunderhill. his speedo might be saying it, but its not happening. more like 115. the holbert car went 120, maybe on a good day, 123mph and the 372rwhp stroker 928 gets a solid 130. Looks like that is about 50hp for 7mph which is in the right range of the math.

oh yes, it is a marvel of racing engineering , in aero , chassis and engine. 1000hp. its made from an old Nascar from the 70s . Its a a work of art. take a closer look next time, it is a BEAST! anyway, THAT gets to 150mph, but nothing ive seen on the track but the 1000hp transam cars (the one that won the championship a couple of years ago, was there) can keep up with it on the straights.

justaguy

Mark I don't smoke crack or anything else for that matter, but I do drink a lot of wine and beer. Especially when arguing on here. I don't think Brian has a speedo or the time to look at it if he did. He uses a GPS data logger.

James Bailey

one big component of your highest speed at the end of a straight is the speed at which you enter that straight......be 5 mph faster in the turn and you carry that all the way down the straight. Light weight, sticky tires, and a good driver often out performs a lot of horsepower....very often

mark kibort

yes, this is very true and could give brian a higher top speed than I would guess.

Thats right! Yeah, i bet since he is on the slicks now , he is closer to that 120mph mark. im sure he is coming off turn 14 with a vengence with those slicks now. im tempted to run up there with him on the 29th and we change rims and tires for a session.

GregBBRD

I'm just guessing, but I'm betting that Brian is smart enough to know that a bunch more horsepower is going to make your car faster than his, without going through the effort of switching tires.

mark kibort

i think you missed the point. There is no question about my car being faster, its about the effect of slicks. i want to see what they will do on my car and i want to see where his driving has gone to by going back to a DOT and see how his car and driving stacks up to where we all have been in the past.

mark kibort

more of that 1000hp mercury. Im going to get Matt to stop shuffle sterring and watch his times DROP! that car will be 2 seconds faster!

IcemanG17

GUYS......great discussion......my best top speed at the end of the straight is 121.2 based off my data logger.....I don't have a speedo....

It varies but typically a good quick lap is around 118-120mph on the main straight....keep in mind I hold flat well past start finish....I typically hit the brakes around the 2.5-3 mark on brief quick stab is it....

MK and I did a power-weight vs time on straight study recently.....a friend with an extremely fast C5 vette that turns 1:50.8 on the bypass at 366whp-3260lbs....it takes him 8.8 seconds from the exit berm of 15 to start finish line which is exactly the same as in takes MK..... A cup car takes 7.8 seconds and shifts about a thousand times.....Darrell Andersons Griggs mustang when it had an unrestricted NASCAR engine also took 7.8 seconds.... My brute 243whp takes 9.3 seconds......

justaguy

Brian so 123 hp is good for .5 sec on the front straight. 200 more hp (cup car) is good for 1.5 sec.

mark kibort

its so hard to really tell by using a stop watch, but think about this. your vet friend would beat the Griggs/anderson mustang pretty easily with 150 less HP!
anderson is one of the "better drivers" and runs now, in the 1:54s with the hill.
even Mike hedman who wheels the stock cup car, and did so in WCGT at sears and took 9th, runs 1:54s. you stick by the Vet all you want, but there are some "funny' things going on with it. the driver is good , no doubt, but when you are 7 seconds faster than another decent driver, something else is going on. put it this way, pobst and I were only a second apart with two cars with the exact same HP and same weight, and him on new tires vs me on old. (not to mention a 10 year newer car professionally prepared for a pro series vs mine built with metwrench.

anyway, until we get more data, or we both show up at the track and get some video, all lthe tire, temp of the day, track conditions, etc etc, skew the data so far it can only point to relative differences.

Ill make it a point to run at sears this year to see big Bill and the Vet. I have a feeling we will be seeing that car on the dyno again soon, not at thunderhill, but at Sears!