What affect does MAF have on Spool up

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12-15-2012, 02:01 PM

#46

refresh951

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Quote:

Originally Posted by Rogue_Ant

About 9°... too much, if you are thinking about just advancing the cam a full tooth.

But you could use an offset key correct from 928 Motorsports.

http://www.928motorsports.com/parts/...aft_keyset.php

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12-15-2012, 02:02 PM

#47

jimbo1111

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If everything mechanical checks out I would suggest you pull the turbo out and check the size of the hot-side wheel you have installed. Most 944 tuners Ive seen usually install a t4 wheel in an 8 housing. Make sure the wheel is no greater than a stage 3 t4. If they installed a stage 5 the difference can be as much as 700 rpm in spool times.

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12-15-2012, 03:34 PM

#48

eman930

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Quote:

Originally Posted by 333pg333

Exactly. Josh I assume you were using an adjustable cam wheel. Just to clarify that with the public. Don't go shifting your stock cam 1 tooth without serious consideration.

Awwwww I was hoping for a quick and easy performance upgrade lol

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12-15-2012, 05:25 PM

#49

User 52121

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Quote:

Originally Posted by Rogue_Ant

Pauly is correct - the turbo will spool a little quicker with the MAF, but a big difference with the MAF isn't so much at peak power, but everywhere else. Dyno testing, we would see about 15% gain at ~1-2psi of boost (M-Tune vs A-Tune).

You could also try advancing your cam a few degrees. That will pick-up lower RPM hp & tq.
It worked so well on my NA, that I went and advanced the cam in my 951 ~3°. Definitely a noticeable difference on spool-up and power driving around.

Where did you pick up the offset cam key Joshua?

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12-15-2012, 06:45 PM

#50

CyCloNe!

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can't you mess with timing via the FQS switch?

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12-15-2012, 07:02 PM

#51

Rogue_Ant

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Quote:

Originally Posted by 333pg333

Exactly. Josh I assume you were using an adjustable cam wheel. Just to clarify that with the public. Don't go shifting your stock cam 1 tooth without serious consideration.

On my 951 I use an full adjustable cam gear; but on my 944NA I used a simple offset cam-key.

Quote:

Originally Posted by refresh951

But you could use an offset key correct from 928 Motorsports.

http://www.928motorsports.com/parts/...aft_keyset.php

Quote:

Originally Posted by fast924S

Awwwww I was hoping for a quick and easy performance upgrade lol

Quote:

Originally Posted by OmniGLH

Where did you pick up the offset cam key Joshua?

928 Motorsports is who I picked up the cam-key from. In-fact, they are my supplier for the (optional) cam-keys on the NA-Tune kit.

Quote:

Originally Posted by CyCloNe!

can't you mess with timing via the FQS switch?

FQS switch can adjust ignition timing. I am talking about camshaft timing - two separate things on the 951/944.

By adjusting cam timing, you adjust when the intake & exhaust valves physically open & close in relation to the crankshaft angle. By closing the intake valves earlier (advancing the cam), it helps build dynamic cylinder pressure earlier in the RPM making more tq/hp. Additionally, it opens the exhaust valves slightly sooner - giving more exhaust energy to help spool up the turbo.