S91 Turbo Cam?

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Dec 26, 2008 | 06:44 PM

#41

Shawn @ VA Speed

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Quote:

Originally Posted by crashly

shawn,
is this the small block , bs3 efi car , that travis quillian tunes???

ash

Yes,i believe so,here's a pic

Dec 26, 2008 | 08:03 PM

#42

otherwhitemeat

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Quote:

Originally Posted by Shawn @ VA Speed

What i'm saying is that to make the power you want at that high rpm with that small turbo your going to have to spin the compressor extremely fast,when doing that you gain a ton of backpressure-and that is whats killing the power.The higher the rpm the higher the backpressure.Yes the wastegate will relieve some pressure but it will take a great deal of exhaust pressure to spin the compressor wheel fast enough to make enough boost.

What would be your thoughts on the can that I showed you...and now installing it at 113 c.l. instead of a straight up 115 and the -12 heads were meant for a sprint car, but now being used in my turbo application?

Dec 26, 2008 | 08:17 PM

#43

Shawn @ VA Speed

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Quote:

Originally Posted by otherwhitemeat

I'm not quite understanding the question-what c.l. is 115?the lsa of that cam is a 115,but that is ground into the cam and cant be changed.
I had a -12 turbo motor back about 7 years ago,385cid with a 101 on it,ran really good,went 7.50's on 10.5's,back then that was pretty fast.

Dec 26, 2008 | 08:30 PM

#44

otherwhitemeat

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Quote:

Originally Posted by Shawn @ VA Speed

I mean, will changing where it is installed at change the cam much. Yes, sorry lsa is 115.. Also what about playing with valve lash and or just changing exhaust rocker arm ratio?

Last edited by otherwhitemeat; Dec 27, 2008 at 12:08 AM.

Dec 26, 2008 | 09:26 PM

#45

crashly

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Quote:

Originally Posted by Shawn @ VA Speed

Yes,i believe so,here's a pic

yes , that it the car
pretty tough for a small block

Dec 27, 2008 | 08:58 PM

#46

DanZ28

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Quote:

Originally Posted by Shawn @ VA Speed

So we have used 3/8'' stem titanium exhaust valves to reduce weight-the titanium exhaust valves arent happy in a turbo motor so you need to replace them every 75 passes or so-but this allows you to use .800 lift cams with no issues

Shawn, is the reason for this because of the heat? I recently saw some Titanium Exhaust valves in a solid roller Turbo car actually stretch the valves from so much heat, they are not titanium any more.

Dec 27, 2008 | 09:51 PM

#47

Shawn @ VA Speed

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Quote:

Originally Posted by DanZ28

Exactly,above 800F titanium starts to weaken,above 1600F the structure of the metal changes,so titanium exhaust valves have a finite life in a turbo motor,just got to know when to get them out.