90mm Maggie Question

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Aug 15, 2006 | 08:20 PM

Rag-Top Rick

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Melting Slicks

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From: N. County/San Diego

90mm Maggie Question

I`m getting ready to drop off my 98 A4 rag-top (w/Vararam & headers) @ A&A for an IC Maggie install/tune.

What gains are the 90mm worth and what throttle body is preferred (GM vs Fast vs BBK, etc.)

Is an upgraded maf necessary to run the 90mm?

Last but not least, do you loose any low/mid-range tq with this set-up?

Thanks in advance for your input.

Rick

Last edited by R.P.; Aug 15, 2006 at 08:23 PM.

Aug 15, 2006 | 09:16 PM

FunCool

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Quote:

Originally Posted by R.P.

Rick

Yes when I put the 90mm throttle body I did lose a little bottom TQ but above 4500rpm I gained more TQ.

Aug 15, 2006 | 10:56 PM

Rag-Top Rick

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Melting Slicks

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From: N. County/San Diego

Quote:

Originally Posted by FunCool

Yes when I put the 90mm throttle body I did lose a little bottom TQ but above 4500rpm I gained more TQ.

Was this prior to the 402?
I`m trying to get an apple to apple example of gains on a stock bottomed LS1 (w/intake/headers) and where in the power band the gains were made.
I didn`t mention it previously but the car will be set up for agressive canyon carving (no track time) so I`m looking for strong performance in the 1500-5800 rpm range.

Thanx, Rick

Aug 17, 2006 | 02:32 PM

Rag-Top Rick

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Melting Slicks

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From: N. County/San Diego

Anyone else have any feedback??

Aug 17, 2006 | 03:18 PM

FunCool

Melting Slicks

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Quote:

Originally Posted by R.P.

Like I said, lost some at the bottom, but gained quite a bit at the top, that was with my 402.
For your kind of racing I may not go with the 90mm. And since you have stock cubes, you would likely not gain that much at the top. I've got a 2.65 pulley, so the stock tb was a big restriction. But with stock cubes and pulley, I doubt there would be as big as a difference.

Aug 17, 2006 | 03:48 PM

Rag-Top Rick

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Melting Slicks

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From: N. County/San Diego

Thanks, the Maggie I bought came with a Reichardt 3.1 pully but it sounds like with a stock bottom-end the 90mm wouldn`t give me much of a gain in the 1500-5800rpm range I use for canyon carving.

Aug 17, 2006 | 06:08 PM

M_T_0

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From: San Antonio TX

the 90mm only helps where the intake is creating a vacum, normally at high rpm's and WOT and a little over 400rwhp, if you look at the plot of my maggie before and after the ecs overdrive pully you will see that the rwtq peaks at about the same rwhp. with the overdrive I start losing rwtq at about 3700rpm without it I lose rwtq at about 4500rpm
this is with a 2.9 blower pully. the 90mm will help more if you are running a smaller pully, but with the 3.1 it probable wont help below 5000rpm.

More Than Zero

Aug 17, 2006 | 07:03 PM

Rag-Top Rick

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Melting Slicks

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From: N. County/San Diego

MTO, thanks ......... it looks like my money would be better spent elsewhere! Mabye I`ll have the ECS alky system that came with the blower installed instead. In So Cal it ever hurts to keep the IAT`s as cool as possible.

I think with the 02 ZO6 cam/comp springs, headers/Random Tech cats and IC Maggie w/3.1 pully it will make for a stout canyon carver.

I`m already saving for a built trans, I`m told it`s just a matter of time!

Rick