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XFI 268 head opinions

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Old May 6, 2008 | 11:56 PM
  #1  
Anti-Venom's Avatar
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From: Springfield, IL
Car: '89 Formula WS6
Engine: L98
Transmission: 700r4/T56
Axle/Gears: BW 3.23
XFI 268 head opinions

Looking at the XFI 268 grind for decent drivability and usable power on the TPI intake. Pretty much at a debate to go with 195 or 180 eliminator AFR's. In one hand the 180's seem to be better matched to the cam grind and CR on stock rotater and would seem to keep velocity in the effective range of the cam. Keeping in mind will run an edelbrock base and LTR's.

On the other hand the lift numbers on the cam seem to possibly work well with the 195's and they would work even better if I went to a bigger more duration grind in the future. 230ish with forged rotator/gears converter. I see alot of people running 190's with short duration cams but there has been substantial increases in the flow numbers on these heads and the 180's flow better than the 190's used to now.

Do you guys think I would lose that much under the curve on a stockish mild setup with the 195's? Or would I see more average pwr with them. The right head with wrong cam better than wrong heads right cam theory? This is a formula that scaled at 3350 w/o driver with 3:23's and a 700. Trying to keep things open for boost in the future.

Wheres my desktop dyno disc?
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Old May 7, 2008 | 01:16 AM
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From: Orange, SoCal
Car: 1990 Pontiac Trans Am
Engine: 355 TPI siamesed runners
Transmission: Tremec T56
Axle/Gears: 12-Bolt 3.73
Re: XFI 268 head opinions

I dont think you can go wrong with either head. The 195's will be better for a larger cam and more stall speed later on. But the 180's seem great for what you have right now. I'd get whichever is lower priced.
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