Techno Ducks Dyno Run
11-23-2007, 08:46 AM
#16
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I would have to say that valve float is not your problem. If the springs were weak, it would not show up all the way across the rpm range. Valve float occurs at high rpms as the springs can't close the valves quickly enough. As far as the strange flucuations in the power, it could be many things and any answer would just be a random guess.
11-23-2007, 10:05 AM
#17
Burning Brakes
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11-23-2007, 10:23 AM
#18
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Jon, get rid of the LBE if running Autothority Stage 2 chips and use the supplied banjo bolt. The boost curve you'll have will not match what the chips were designed for. Did you recieve instructions with the chips?
11-23-2007, 12:20 PM
#19
Nordschleife Master
Once the broken exhaust manifold stud is fixed the first round of upgrades i plan to do are a proper boost controller, Vitesse chips for the stock 26/6 and probably a Tial wastegate. But to fix this stud i am probably going to have to pull the head..which means i want to do a Cometic head gasket and replace all the lines and hoses under the intake while its apart...which turns what would have been a $15 job (for bits and extractors) to a $3-400 job for all the new parts.
11-23-2007, 01:27 PM
#20
RL Community Team
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Ah yes... the slippery slope...
11-23-2007, 03:14 PM
#21
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I love the Interweb speculation from the kids on this thread.
J.R. dynoes his F1 vintage Cosworths on THIS dyno.
Anthony dynoes his GRAND AM Hondas on THIS dyno.
If this dyno op says its a spring problem, ITS A SPRING PROBLEM.
I'll tell you a story...
The last time one of J.R.'s customers F1 cars was in for mis-fire.
3.5 liter Cosworth.
Car kept coughing at 9,000, and this is an 11,000 RPM engine.
He told Geoff to HOLD IT UNDER LOAD AT 8,000 RPM.
"You TRYING to blow this thing up?", he says.
"Hold it at 8,000"
Just so you guys understand - this means foot flat on the floor, but the dyno stops it at 8,000 RPM. That makes heat.
So they did.
Coolant started coming out of the right bank.
Problem found - weak headgasket.
Try to do THAT on a Dynojet.
Nor does saying that two guys named "Anthony" and "JR" use the dyno
I stand by my assertion that valve float will destroy an interference engine because I've seen it happen (on a Yamaha R6 engine).
Valve float won't cause the kind of fluctuations that that graph has, and if Techno Duck says that the car runs fine, then I have to assume that he would notice if the power was fluctuating +/- 20hp over 800 rpm
I don't mean to get into a pissing match over this or accuse anybody of anything, but it seems like the dyno sensors might not be completely dialed in. If they're off for one car, they'd be off for all cars, so having a bunch of 944's dyno at around the same power again just proves that 944's all make about the same hp
11-23-2007, 03:18 PM
#22
Official Bay Area Patriot
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Sorry Jon, detonation. It could also be that timing map on the aftermarket chip.
If they gave you STD correction and not SAE, I might go somewhere else next time. Most shops won't even print out STD for you anymore, as SAE represents more realistic conditions.
If it's running strong and you can't hear any knock, I might not even worry about it.
If they gave you STD correction and not SAE, I might go somewhere else next time. Most shops won't even print out STD for you anymore, as SAE represents more realistic conditions.
If it's running strong and you can't hear any knock, I might not even worry about it.
And this is why I ditched my FR Wilk Chip and refuse to chip a 944 NA...
That dyno graph tells all. Jon, I'd put your stock chip in and get it dynoed again. I have never seen a graph that all over on an NA dyno.
11-23-2007, 05:12 PM
#23
Nordschleife Master
I love the Interweb speculation from the kids on this thread.
J.R. dynoes his F1 vintage Cosworths on THIS dyno.
Anthony dynoes his GRAND AM Hondas on THIS dyno.
If this dyno op says its a spring problem, ITS A SPRING PROBLEM.
I'll tell you a story...
The last time one of J.R.'s customers F1 cars was in for mis-fire.
3.5 liter Cosworth.
Car kept coughing at 9,000, and this is an 11,000 RPM engine.
He told Geoff to HOLD IT UNDER LOAD AT 8,000 RPM.
"You TRYING to blow this thing up?", he says.
"Hold it at 8,000"
Just so you guys understand - this means foot flat on the floor, but the dyno stops it at 8,000 RPM. That makes heat.
So they did.
Coolant started coming out of the right bank.
Problem found - weak headgasket.
Try to do THAT on a Dynojet.
11-23-2007, 06:18 PM
#24
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You think Carlos? Im really not sure, just sort of a conservative guess. 3'' SFR exhaust and no cat, Autothroity Stage 2 chips, LBE, cant remember if anything else was done. I definetley want to get rid of the chips though..have heard not so great things about them in the upper RPM range.
Email me the video if you get the chance... jjeng951 at gmail dot com
Email me the video if you get the chance... jjeng951 at gmail dot com
Also, guys, two 944s are being talked about in this thread. Jon dynoed his NA. We went off on a tangent when i mentioned the 951 I sold this summer to jon (sort of).
11-23-2007, 08:43 PM
#27
No, wish I was, didnt know about it. Plus the motor is still apart, Just got my JM camshaft and I need a clutch, Then she is on the road again, just in time for winter :-(
11-23-2007, 09:55 PM
#29
Nordschleife Master
DVC, there was no air fuel readout available.
The car runs fine, im not going to worry about it..
. I actually put the stock y-pipe back in tonight. I couldnt take the noise any longer.
All i gotta say is thank gosh for lifts...made it a pretty simple hour and a half job.
The car runs fine, im not going to worry about it..
. I actually put the stock y-pipe back in tonight. I couldnt take the noise any longer.All i gotta say is thank gosh for lifts...made it a pretty simple hour and a half job.
11-23-2007, 10:04 PM
#30
Nordschleife Master
I also forgot, i read the receipt for all the exhaust work and saw the one for the Fabspeed downpipe. I dont think its the downpipe because as far as i know Fabspeed never sold one (though im not 100% sure about that). What i think the car actually has is the Fabspeed midpipe (test pipe, catbypass..whatever you want to call it) and a SFR catback. I havent had the time to get the car on a lift and check things out yet however.