305 to 350
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Joined: Aug 2008
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From: Stevensville Maryland
Car: 1992 Firebird Formula
Engine: L98
Transmission: T5
Axle/Gears: Posi
305 to 350
i know every1 has this as a topic but i need help im 17 i need a budget 350 build im not sure if i want to stroke it to a 383 or wat i know i want to leave it tpi i want a good daily driver for gas but i want something were i can kick a ls1 *** or atleast hang with them or beat the rice burners i want to put it in a 92 formula with a lb9 in it now and a t5 with about a 120000 on it now and wat else would i need to drop it in new motor mounts or wat thanks.
Joined: Mar 2000
Posts: 43,187
Likes: 42
From: Littleton, CO USA
Car: 82 Berlinetta/57 Bel Air
Engine: L92/LQ4 (both w/4" stroke)
Transmission: 4L80E/4L80E
Axle/Gears: 12B-3.73/9"-3.89
383 and budget don't belong in the same sentence.
Well, you can build a "budget" 383, but not if a budget 350 is your first thought.
The best "budget" would be to find an '88-'99 truck 350 with at least a good shortblock. If '88-'95, put your LB9 heads on it. If '96-'99, use the heads as well. If you are living right, you might even find one that doesn't need to be rebuilt.
Keep roller lifters. Your LB9 has them, the '88-'95 truck will not while the '96-'99 truck will.
This is where things get complicated. Keeping up with LS1's with TPI is not easy. Do-able, but costs start to add up. Exhaust is a must, figure on $1000 right there alone. More cam is almost certain to be required, and then you have the snowball effect - new valve springs, maybe get the top of the valve stem guides cut for sufficient valve travel.
Two other things will be required - TPI hardware upgrades, and PROM changes. The "easy" route is the Holley/Weiand Stealth Ram, which replaces both the poor flowing and RPM limiting stock TPI base & runners, as well as the stock plenum. Drawbacks include not being emissions legal, needing a different throttle body, and different injectors (although you should do that with a 350 upgrade, anyway). The Stealth Ram is available in both the regular (LB9) and Vortec ('96-'99 truck) head style.
Of course, now that your 350 can pretty much hang with the LS1's, your T5 isn't long for this world. . .
Got $6000-$10,000? If you can't beat 'em, join 'em and do an LS1/T56 swap.
Well, you can build a "budget" 383, but not if a budget 350 is your first thought.
The best "budget" would be to find an '88-'99 truck 350 with at least a good shortblock. If '88-'95, put your LB9 heads on it. If '96-'99, use the heads as well. If you are living right, you might even find one that doesn't need to be rebuilt.
Keep roller lifters. Your LB9 has them, the '88-'95 truck will not while the '96-'99 truck will.
This is where things get complicated. Keeping up with LS1's with TPI is not easy. Do-able, but costs start to add up. Exhaust is a must, figure on $1000 right there alone. More cam is almost certain to be required, and then you have the snowball effect - new valve springs, maybe get the top of the valve stem guides cut for sufficient valve travel.
Two other things will be required - TPI hardware upgrades, and PROM changes. The "easy" route is the Holley/Weiand Stealth Ram, which replaces both the poor flowing and RPM limiting stock TPI base & runners, as well as the stock plenum. Drawbacks include not being emissions legal, needing a different throttle body, and different injectors (although you should do that with a 350 upgrade, anyway). The Stealth Ram is available in both the regular (LB9) and Vortec ('96-'99 truck) head style.
Of course, now that your 350 can pretty much hang with the LS1's, your T5 isn't long for this world. . .
Got $6000-$10,000? If you can't beat 'em, join 'em and do an LS1/T56 swap.
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