Exhaust question

doodguy said:

Whipple

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Dahh thats what i get for asking a question at 6 am lol.A dumb question at that!!!.

Tommy V said:

Dahh thats what i get for asking a question at 6 am A dumb question at that!!!.

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No worries lol :cheers:

Tommy V said:

Dahh thats what i get for asking a question at 6 am lol.A dumb question at that!!!.

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As my wife says ( 2nd grade teacher) Sir, there is no such thing as a dumb question. The issue is being too embarrassed to ask about something you do not know the answer or are unsure.

U wouldld not think u would have a flatline issue with that setup,especially since u changed the valve springs already.I really doubt its your exhaust since u have headers and no cats.Be cool to see what fixes this issue.

It's a PD thing. Sure port everything, cams, bigger pulley and whatnot you can move that flat spot higher but it will still be there. No secret PD's fall flat in the upper rpms where they lose efficiency. Price you pay for that "low end torque".

Nothing wrong with it, not like it falls off power big time.

Jay-rod427 said:

It's a PD thing. Sure port everything, cams, bigger pulley and whatnot you can move that flat spot higher but it will still be there. No secret PD's fall flat in the upper rpms where they lose efficiency. Price you pay for that "low end torque".

Nothing wrong with it, not like it falls off power big time.

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So if he is flatling at 6k with 900hp, would it be safe to say if he could raise that flat line to 8k the hp should go up with it?

jhatley7 said:

So if he is flatling at 6k with 900hp, would it be safe to say if he could raise that flat line to 8k the hp should go up with it?

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GREAT question

In theory yes. Just running out of blower steam.

I made this same suggestion (blower out of steam) in the OP original thread on the flatlining power curve and was shown the door, no f'in way is it out of steam, Copos and Drag Paks spin their 2.9L to 25k rpms etc etc

Hard to argue either way. SOMETHING is holding the airflow from getting to the motor if the blower itself isn't out of steam, whether it be the intercooler brick or system is overwhelmed, cam timing is not tuned right, spinning tires on the dyno, clutch fried (cant recall if this is an auto)....

It can be overspun no problem, and hold power above 6,500, but running out of steam the power doesn't climb anymore. All the other supporting mods are just a bandaid.

Im still leaning a little that it is tune related, I checked logs again and I see airflow PID maxing out and timing going flat right at 6,000 rpms. Cant imagine it doesn't need ANY more timing for the rest of the RPM range, I also noted the cams are not being retarded AT ALL past 6,000rpms, which again will cause power to really stall out.

What about maf sensor range maxing out.Ive seen that happen in cobra,s .Not sure wheir the s550 maf maxes out.

[MENTION=28803]TooSoonJunior[/MENTION] i hope you dont feel like i somehow showed you the door?? If i missed a response to you or something it was only an over sight just been crazy busy lately. I welcome all opinions. I surely dont have the amswers. Thats why im posting.

I was advised it's being allowed to go to 24 on timing. I don't know how to read the logs.

Car is a manual with rxt clutch, and to the best we can tell tires aren't spinning on dyno.

Lund is my tuner and we spent most of the day on the dyno trying to figure what's holding it back. He said he can't see anything in logs that might be holding it back. He thinks the whipple just isn't making more air which sounds about right as Anthony Ballard said he's also maxing out at 22psi.
[MENTION=9456]Tommy V[/MENTION] I don't think so because there are people making much more power than I am with more boost same stock maf I believe.

doodguy said:

[MENTION=28803]TooSoonJunior[/MENTION] i hope you dont feel like i somehow showed you the door?? If i missed a response to you or something it was only an over sight just been crazy busy lately. I welcome all opinions. I surely dont have the amswers. Thats why im posting.

I was advised it's being allowed to go to 24 on timing. I don't know how to read the logs.

Car is a manual with rxt clutch, and to the best we can tell tires aren't spinning on dyno.

Lund is my tuner and we spent most of the day on the dyno trying to figure what's holding it back. He said he can't see anything in logs that might be holding it back. He thinks the whipple just isn't making more air which sounds about right as Anthony Ballard said he's also maxing out at 22psi.
[MENTION=9456]Tommy V[/MENTION] I don't think so because there are people making much more power than I am with more boost same stock maf I believe.

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Anthony also has Comp stage 2 cams and head work with ARH 2" headers. But he did break the 1k mark without spray. Wonder what Whipple has to say on the subject. Aren't the Cobra Jets making over 1K with the same Whipple we have?

No No doodguy it was the others in your thread that "showed me the door" not you at all.

I am still learning tuning these cars as well, but regardless of what the car is being "allowed" to go to, its hitting that max around 6,000rpms. So if Lund says 24* is max, its hitting that at 6,000rpms. My argument is if it likes 24* at 6,000rpms, basic spark advance rules say you should continue to further advance higher up the rpm range you go. Not saying a lot, maybe 1 or 2 degrees more, but as I am sure you are aware a few degrees can be huge power difference.

Yes Ballard maxed out around 21psi, but I bet it was at a much higher blower speed than you (smaller pulley) and better flowing cams/exhaust. So you're measuring restriction and seeing 21psi.

And from all I can tell you ARE maxing out your MAF, but it shouldn't matter to the tune, timing and fuel come mostly from rpm and load, even with the MAF flatlined but rpms still climbing, you can tune around the maxed out MAF.