LB9 to L31 swap
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Car: 92 T/A 'vert
Engine: Mild .040 over L98 4 bolt mains
Transmission: Mostly stock 700R4, 2600 Vigilante
Axle/Gears: LS1 3.42
LB9 to L31 swap
If I use a 350 vortec short block for my swap, will the ancillary parts, (harmonic balancer, flex plate, etc.), from the 305 TPI bolt up correctly to the new engine? Do I use engine specific or model specific parts? I'm getting all new stuff so I want to know what to order. Thanks!
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Car: 92 T/A 'vert
Engine: Mild .040 over L98 4 bolt mains
Transmission: Mostly stock 700R4, 2600 Vigilante
Axle/Gears: LS1 3.42
Re: LB9 to L31 swap
Sorry. I was a little vague. The TPI in question is my 'vert which is a '92, so I should get parts for a '92 and not for a truck, correct?
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Car: 92 T/A 'vert
Engine: Mild .040 over L98 4 bolt mains
Transmission: Mostly stock 700R4, 2600 Vigilante
Axle/Gears: LS1 3.42
Re: LB9 to L31 swap
Got a set of small chamber Trickflow 175's, the ones patterned after 113's and will work with a 305 , so yeah, 305 heads. I was gonna' warm up the 305 but am looking at a pretty good deal for a rebuilt L31 short block so I'm undecided but trying to talk myself into going 350. It just kills me to dump my meticulously maintained, 55K mile 305 bottom end.
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Car: 92 T/A 'vert
Engine: Mild .040 over L98 4 bolt mains
Transmission: Mostly stock 700R4, 2600 Vigilante
Axle/Gears: LS1 3.42
Re: LB9 to L31 swap
Oh. The heads are '87 - up intake face.
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Car: 92 T/A 'vert
Engine: Mild .040 over L98 4 bolt mains
Transmission: Mostly stock 700R4, 2600 Vigilante
Axle/Gears: LS1 3.42
Re: LB9 to L31 swap
Gotcha'! Thanks for the help.
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Car: 92 Firebird
Engine: Supercharged 6.0
Transmission: T56
Axle/Gears: 8.8 3.73
Re: LB9 to L31 swap
Pop the vortec reluctor wheel off behind the timing cover to use the TPI balancer. If you dont it will push the balancer out .125" which is enough to wreck your belt
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Car: 92 T/A 'vert
Engine: Mild .040 over L98 4 bolt mains
Transmission: Mostly stock 700R4, 2600 Vigilante
Axle/Gears: LS1 3.42
Re: LB9 to L31 swap
Good to know. I'm pretty sure this particular engine comes w/o the timing cover, so if it's there, it'll be easy to see/remove. Thanks!
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Car: 92 T/A 'vert
Engine: Mild .040 over L98 4 bolt mains
Transmission: Mostly stock 700R4, 2600 Vigilante
Axle/Gears: LS1 3.42
Re: LB9 to L31 swap
Here's my quandary: The following 2 pics show the 2 engines with the parts I've accumulated over the past coupla' years, with adjustments for slightly different head flow due to bore size and a difference in compression due to same. Now, I understand that Comp Cams' "desktop dyno" is not 100% accurate but I believe it gives a pretty good comparison of the 2 motors with the same equipment. Due to the low RPM nature of TPI, (though I won't be using the stock stuff, the program doesn't allow for any other choice), I gain a a fair amount of torque but not all that much HP. And, while torque is more what I'm interested in, (don't need big numbers on the dyno/time slip; just wanna' terrorize a few kids in their Hondas), I'm gonna' have enough to probably have drive line/traction issues with the 305, let alone the 350. Also, the 350's torque curve appears to be a lot "peakier", (is that a word?), than the 305. In other words, my return on investment, (around $1000-1200), is rather low. If the 305 was shot, there would be no doubt about stepping up. But, it checks out good, (good compression/leak down, no oil burning, no noise, etc.). I dunno'.
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Car: 1986 trans am
Engine: 305/350
Transmission: 5 speed
Axle/Gears: 3.27
Re: LB9 to L31 swap
i stand by what i said! i always seem to miss the dates but this is relevant to what im currently doing.
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