Robby

Yes, I'm not exactly sure where 4000rpms is in 3rd, but could find out... 6400 should be right at 99mph in 3rd though assuming you're running stock RD tires. At 6500 you should be just over 100 and should be hitting the rev-limiter. Either way, you would be shrting yourself if full accelaration is what you're after. Like Adrial said, you should be shifting at about the 6000rpm range, or maybe slightly before to be in the meaty part of your power bands. I've been told by some that you should never go above 5500 for max accelaration, but this can depend on the specific car (Turbo or Turbo S) AND/OR what kind of mods you may have. I'll try to get my 60-100 times and/or 4000-6000rpm 3rd gear tests for comparison soon- mine's a Turbo S, but isn't in the best condition unfortunately...

rage2

[quote]Originally posted by Konstantin:
<strong>hello
can someone do the folkowing test and tell me the time?
Start at 3000 rpm in third gear go on WOT and stop teh time from 4000 to 6000 rpm in third gear.
I would like to know the times.
A stock car from my friend with APE chips and LBE needs 7,3-7,6 sec with two people in teh car and half tank gas.
My best was 4.5 sec with MAF bigger Turbo etc.

Rage2?
Paul?
89944Turbo?

Thanks

Konstantin</strong><hr></blockquote>

There's a bit too much snow to test right now. I'll get to it as soon as the weather co-operates.

My GTech Pro run at 14psi :

1/4 mile - 12.89s @ 119mph
0-60 - 5.8s (winter, lots of wheelspin)

I should be able to hit low 12's with real tires and higher boost when the weather gets nicer.

rage2

I went back to the video that I posted, and realized I had a very accurate way of telling how fast I ran 4000rpm to 6000rpm in 3rd gear... My video editing software can go frame by frame, with timestamp accurate to 3ms.

According to my video, I ran 4001rpm to 5986rpm in 4.30s. The actual time should be a few ticks faster, as I got wheelspin and the revs hovered around 4500rpm for about 0.5s.

The weight of the car for that run :

2950lbs - Car w/10% tank fuel (I had 1/2 a tank for the run, not sure how much more it weighs)
350lbs - Me and passenger.

Konstantin

Helllo
here a pic for teh gearing in a 951
<a href="http://www-public.tu-bs.de:8080/~y0003315/gearboxratio.html" target="_blank">http://www-public.tu-bs.de:8080/~y0003315/gearboxratio.html</a>
4000 are 60 mph and 6420 are 160 km/h or ~100 miles.
I test the time from 4000to 6000 rpm because it is easier. My rev limite ris at 7000 and I run many times up to 6900 without problem. 5500 is to early for my car.
i think the 4000 to 6000 RPM time is ok to test and very easy. Also teh engine do not get abused at 6000 rpm.
@ rage. I expect your car to be faster than the 4.2 sec. I had 4.5 sec. I thing you shoul be at about 3.7 sec.
I had a enail with the times and if I remeber corectly a 370 or a 420 HP 951 will do 3.7 Sec with stco tires. If you use 17" or 18" you must calculate teh time from 62 mph to 94 mph but go always with the rpm and not with the mph as the speed is not accurate.

Konstantin

Robby

I ran the 60 - 100 time tonight w/my stock Turbo S (no chips or anything, plus, 152K)- I didn't have much time, and I forgot about the 4000 - 6000rpm test, but, the first time I did the 60 - 100 test, I dropped the stop watch, and when I got it picked back up, I was just above 100- it read 8.9something. I assume I lost about 1 second. The second time I hit it in 7.97 seconds. Both times I got going about 55mph in 3rd, and rolled on the throttle quickly- by the time I reached 60, I was full on, and had started the stop watch. I shifted as close to 6000rpm as possible (about 90) and passed 100 in 4th. The second time of 7.97 sounds about right for a Turbo S to me. The stock Turbo S ran about 5.5 w/professionals, and the 1/4 at about 14.2 @ 101- I don't care what Porsche claimed- we know a 13.5 is BS- even C&D only got a 13.9 w/the EURO gearing. Anyway, if you factor in a 6.0 sec run to 60, then I would have hit 100 in a hair under 14 seconds, and 101 or 102 a hair later. I also didn't have to shift from 2nd to 3rd like the pros would have done on a 1/4 mile run (it should come just above 60), thereby saving a few 1/10's. Anyway, this method has to be highly inacurate overall, as I was relying on my reaction time, as well as the speedo and tach too much- I'd take a G-Tech reading over it any day, but it should be w/in 1/2 sec or so. Anyway, hope this helps...

Paul Bloomberg

Rage2,
Hope you dyno that thing soon. I am lookin to upgrade and I like to see where the bigger injectors/turbo would leave me in the dust!
Paul

86944turbo

With my old 2.5 litre Milledge motor, I could record dead accurate 4000-6000 rpm runs, due to the fact that MoTeC allows you to keep the last 20 minutes @ 1/10 per sec. intervals. On high boost (240 kpa) 20.6lb., It always ran 3.0 to 3.1 seconds. In cold (40F ambient), I recorded a few 2.9 second runs. I always found my tach to be a little optimistic. That motor dyno'd at 434 h/p, (rear dyno revealed 392) My 3.1 is significantly more powerful, but I have a 6 spd. so cannot do a direct comparison. Since it has over 100 more flywheel H/P it would probably cut another 1/2 second off that time.

rage2

Still had a bit of 103 octane left before the car was empty, so I went out for a quick blast. Drove out of town, did 3 runs and recorded it with my camcorder again (very crudely duct taped onto the rear seats hehe).

First run, 3.7s, got light wheelspin. Second run, 3.5s. Third run (Engine Temp starting to get hot) 3.7s. Gas light came on, turned around, cruised in 5th to conserve fuel, and went home.

Car ran at 20psi peak (4500rpm), 18psi at 6000rpm for all 3 runs. Car was still making boost at 4000-4500rpm, started slowly dropping off after that.

Konstantin, your 3.7s guess for my car was pretty accurate =).

Luke

I wonder what your 0-60 would be on 18 in wheels?

Konstantin

@86944turbo
if you stop the time from 62 mph to 94 mph with your 6 speed it is teh same.
Are you say you needed 3.1 Sec!!!!
say that again. This is really fast!!

or check the RPM at 94 mph (it dosn't matter which gear just chose teh smallest posible) and tell me the time with your new engine.

Thnaks

This is really amazing and I thought the 4.5 sec was fast.

Konstantin

Konstantin

Konstantin

@ Rage 2. yes thes enumbere are pretty accurate and messured with many cars.
I guess teh dyno shop wa scrap. Did tehy had a fan for teh inetrcooler, messured teh barometric this day, teh temp the altitude, calculate the wkeel spinn messure teh boost while dynoing etc tec?
I think you got a number for 14 PSI boost and not for teh 17 PSI boost since the boost went down in your car. so over 300 RWHP with 14 PSI is very good. Cann you tell me what boost did you had at 6000 rpm?

Konstantin

rage2

[quote]Originally posted by Konstantin:
<strong>@ Rage 2. yes thes enumbere are pretty accurate and messured with many cars.
I guess teh dyno shop wa scrap. Did tehy had a fan for teh inetrcooler, messured teh barometric this day, teh temp the altitude, calculate the wkeel spinn messure teh boost while dynoing etc tec?
I think you got a number for 14 PSI boost and not for teh 17 PSI boost since the boost went down in your car. so over 300 RWHP with 14 PSI is very good. Cann you tell me what boost did you had at 6000 rpm?

Konstantin</strong><hr></blockquote>

Yes, they had a fan. The air temp was getting cooler, but the temps at the manifold were not. Intercooler was probably not cool enough (temps read off SDS). Boost was 14psi at 6000rpm. That netted 244.8ft/lbs of torque, calculates to 279.7hp. My peak HP was made at peak TQ, 4400rpm. My peak HP should've been at 5500rpm or higher, unless there's something seriously wrong with the turbo =).

Jim Nowak

Rage2,

I'm a regular on the 928 board but I've been reading all the 944 turbo posts recently. I'm trying to figure what I should expect from turbocharging/surpercharging my 928 and I will give a list of modifications at the end of this post. However, I see inconsistencies in the rear wheel horsepower numbers. Could this be caused by different dynos?

It appears that, in fact, many of the differences may be caused by the types of dynos and their opptomistic or pessimistic nature as well as input of the correction factors. For accuracy, Dyno Jet is the absolute best and has become the standard for measurnig RWHP but even the Dyno Jet is no good if the correction variables are not accurate.

I would be leary of letting many engine builders dyno numbers if it is on their own equipment. An independent dyno is the best way to measure hp increases and determine if you got your moneys worth.

How much estimated RWHP, on a Dyno Jet, should I see if I prodded the engine with 5lbs or 10lbs of intercooled boost? I recorded approx 270 RWHP and 315 RWTQ on a dyno jet before my recent addition of the Extrued Honed Euro S intake and the Electromotive Tec II engine management(replaces stock CIS). The engine is 5.4L and remember you've got to think double in terms of displacement.

Jim Nowak

1979 928 (2900 lbs)
88 S4 block bored to 104mm 10.4:1 CR
1985 & 1/2 944 heads (I know you like to see that)
J&E forged and coated pistons
Redrilled crank to fix high speed oiling problems
Devek 2-valve billet cams
Extrued Honed Euro S induction
Electromotive Tec II engine management
Devek racing radiator & S4 cooling fans
S4 brakes to slow her down

rage2

[quote]Originally posted by Jim Nowak:
<strong>However, I see inconsistencies in the rear wheel horsepower numbers. Could this be caused by different dynos?

It appears that, in fact, many of the differences may be caused by the types of dynos and their opptomistic or pessimistic nature as well as input of the correction factors. For accuracy, Dyno Jet is the absolute best and has become the standard for measurnig RWHP but even the Dyno Jet is no good if the correction variables are not accurate.</strong><hr></blockquote>

Most likely. While the dynojets are pretty accurate (assuming you don't get any wheelspin) they have some correction factors that differ from location to location. They can be turned on or off. From what I was told, my dyno runs were done with no corrections.

[quote]Originally posted by Jim Nowak:
<strong>I would be leary of letting many engine builders dyno numbers if it is on their own equipment. An independent dyno is the best way to measure hp increases and determine if you got your moneys worth.</strong><hr></blockquote>

I think the dynojet's intended usage is to get a baseline and compare modifications. Stick with one dyno, one set of correction factors. Find out how much *more* power it's making based on the different mods. For me, I have a slightly skewed agenda, I need to hit that 400rwhp reliably just for bragging rights (but I do care about mods too!) =).

[quote]Originally posted by Jim Nowak:
<strong>How much estimated RWHP, on a Dyno Jet, should I see if I prodded the engine with 5lbs or 10lbs of intercooled boost? I recorded approx 270 RWHP and 315 RWTQ on a dyno jet before my recent addition of the Extrued Honed Euro S intake and the Electromotive Tec II engine management(replaces stock CIS). The engine is 5.4L and remember you've got to think double in terms of displacement.</strong><hr></blockquote>

I'm jealous already =). Maybe we should start dyno pool #2... see who comes closest. Are you using 91 octane fuel or race fuel? With your high compression ratio, 91 octane will have a hell of a time with 10psi. I learned over the last month how crappy 91 octane really is =).

2900lbs... you're lighter than me, now I'm REALLY jealous!

Jim Nowak

Rage2,

Right now my engine is normally aspirated and I'm using 91 oct. I haven't had any problems with detonation but I expect there could be some when I supercharge the motor. I pulled off the old CIS fuel injection in favor of an engine management system that has a good knock sensor so I don't blow holes in the pistons and a MAP sensor so air-flow would not be impeaded.

I haven't had the engine dynoed with the addition of the Extrued Honed Euro S induction or the engine management but I'm expecting big things. My engine builder, from Devek, thinks I will see an additional 30% gain in my RWHP and TQ with the mods. I guess they should know since they are getting over 450 RWHP out of their normally aspirated street driven/race 928.

Jim Nowak