Is this too much cam for it ?
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Is this too much cam for it ?
A fried of mine just replaced his dying 305 in his TPI 85Z28 with a stock 350. It has centerbolt iron L98 heads from an 89Z28 and a CompCams Magnum 280H cam. It's a 230/230 duration at 050 and 488 lift. Is that duration too much for his stock 85 computer to handle ? He has a 5 speed behind it and it's a little sluggish. Feels like a high 14 second car. Would a custom chip help any ?
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1991 Z28 5.7 TPI
ZZ4 heads, ZZ4 cam, Harland Sharp roller rockers, Accel base, SLP siamesed runners, 52MM SLP Throttle Body, Hooker Headers, Flowmaster catback, MSD6A ignition, Home made ramair system, 2500 stall, bullet proof 700R4, aluminum driveshaft...
Soon to be installed. WC T5 !
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1991 Z28 5.7 TPI
ZZ4 heads, ZZ4 cam, Harland Sharp roller rockers, Accel base, SLP siamesed runners, 52MM SLP Throttle Body, Hooker Headers, Flowmaster catback, MSD6A ignition, Home made ramair system, 2500 stall, bullet proof 700R4, aluminum driveshaft...
Soon to be installed. WC T5 !
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Joined: Aug 1999
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From: College Station, Tex USA
Car: 89rs
Engine: 400Sb
Transmission: Tremec 3550
<font face="Verdana, Arial" size="2">Originally posted by crucial:
Is that duration too much for his stock 85 computer to handle ? He has a 5 speed behind it and it's a little sluggish. Feels like a high 14 second car.
</font>
Is that duration too much for his stock 85 computer to handle ? He has a 5 speed behind it and it's a little sluggish. Feels like a high 14 second car.
</font>
Yep.
<font face="Verdana, Arial" size="2">
Would a custom chip help any ?
</font>
Would a custom chip help any ?
</font>
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Joined: Sep 2001
Posts: 6,111
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From: Ontario, Canada
Car: 1988 Firebird S/E
Engine: 406Ci Vortec SBC
Transmission: TH-350/3500stall
Axle/Gears: 7.5" Auburn 4.10 Posi-Traction
I'd go with something around 206 to 212 @.050" timing, around .440 lift with a 112 lobe seperation The computer won't like that 280H magnum.
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From: Loveland, OH, US
Car: 4
Engine: 6
Transmission: 5
If that's a TPI motor, then that cam is a gross mismatch to the rest of the system. Since TPI has no top end, that combo kills the only remaining strong point of the TPI, namely its low end torque. It will definitely make the car sluggish, or worse. I believe the stock cam would probably make it go faster.
I suspect it's outside of the range of possibility for any significant help with a chip.
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"So many Mustangs, so little time..."
ICON Motorsports
I suspect it's outside of the range of possibility for any significant help with a chip.
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"So many Mustangs, so little time..."
ICON Motorsports
Supreme Member
Joined: Sep 2001
Posts: 6,111
Likes: 53
From: Ontario, Canada
Car: 1988 Firebird S/E
Engine: 406Ci Vortec SBC
Transmission: TH-350/3500stall
Axle/Gears: 7.5" Auburn 4.10 Posi-Traction
<font face="Verdana, Arial" size="2">Originally posted by zippy:
too much duration and where did he get the extra .008 of lift?</font>
too much duration and where did he get the extra .008 of lift?</font>
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Joined: Aug 1999
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From: College Station, Tex USA
Car: 89rs
Engine: 400Sb
Transmission: Tremec 3550
Comp updates their old grinds periodically and pushes the lift up slightly.
The original XE268 was .450 lift. Then .454 and now I think it is close to .46.
The original XE268 was .450 lift. Then .454 and now I think it is close to .46.
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From: Chander, Arizona USA
Car: 2006 Silverado 1500
Engine: 5.3L
Transmission: 4L60E
there wasn't an original xe268 that is old. xe is extreme energy cams and that is new design. the old 268h is the high energy (old series) and is still .454 lift. the 280h is a magnum (old series), and the lift is still .480.
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