my stock 305 tpi is getting tired and burns a bit of oil so im plannin on throwing in a new motor.i found somebody who has a 383 thats balanced for a 4 speed and has mostly edlebrock parts on it..my ? is would i be able to fit that motor in my ta ??can i fit my exitsing 700r4 in with the 350??and also what do i do about my fuel pump beacuse i know that my stock electric pump wont work with a carberated motor.if there is any other hints please fill me in.OHH YEAH ONE LAST THING everybody is telling me that i should go with 342s if i have tpi but what if i swap and put the 383 in can i put 373s in??

 

It will certainly fit. You've got some work ahead of you, though.

"balanced for a 4 speed" - What exactly does that mean? Typically, you need an externally balanced harmonic damper and flexplate/flywheel. If that's all you mean, just get an externally balanced flexplate for your automatic.

The TH700R4 will bolt up, but your starter won't because the externally balanced flexplates are typically 14". You'll probably need a ministarter to make it work. And your inspection cover probably won't fit. (BTW, what do you mean by "fit my existing 700r4 in with the 350"?)

For the fuel pump, either take the electric out of the tank and put a mechanical on the engine, or get a 3-port fuel pressure regulator to drop the pressure down to carb levels. With a 3-port you can retain the fuel return line. Since you'll be deleting the ECM, you'll need to get a way for the torque converter to lock, and I believe you'll have some electric fuel pump relay issues to work through if you keep it.

Gears have absolutely nothing to do with what size engine you have. It's purely a matter of what you want to do with the car when you're done. If going up mountain passes at 75 mph is your goal, 3.73's probably aren't what you want. If you want a good comprise between off-the-line performance and highway cruising, the 3.42's are a good choice. If all you worry about is getting away from the stoplight or starting line, then 3.73's or 4.10's are the way to go.

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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R4. 2.93 limited slip. 2-1/2" cat-back, ZZ3 intake, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 CC system w/'87 LB9 block, ZZ3 cam, ported World 305 heads, Hooker 2055 headers, 3" Catco cat & 3" catback, restalled TC, Spohn SFCs).
57 Bel Air, my 1st car. '66 396, 9.7 CR forged TRWs, Weiand Action+, Holley 750VS w/4150 conversion, GK 270 cam, Magnum rockers, Jacobs Omnipack, 1-3/4" Hedders & 3" Warlocks, TH400 w/TCI Sat Night Special conv & Trans-Scat shift kit, MegaShifter, 3.08 8.2" 10-bolt w/Powertrax, AMSOIL syn lubes bumper-to-bumper. Idles smooth @ 600 RPM in D. Best 15.02/95.06 @ 5800' Bandimere (corrected 13.93/102.4 @ sea level).

 

what i meant about fitting my 700r4 with the 350 is i just wanted to know if it would bolt up or not.about the externally balanced flexplate ill find out about that on monday.i think ill use the electric fuel pump and get the fuel pressure regulater like u said.

 

sorry i forgot to add this is...what do i do about my torque converter dont they make like manual locking converters or something..im too sure about the whole locking up thing can u explain how it works ?

 

One more time, what 350? I thought you were asking about a 383. The 383 uses a 350 block, is that what you're talking about?

The TH700R4 comes with a torque converter with a clutch built in. The computer completes a circuit to ground in the higher gears to "lock" the converter (the power to the tranny goes through a switch connected to the brake pedal). The lock-up clutch reduces the difference between the engine and transmission speed (slipping or fluid coupling loss), resulting in improved economy and reduced transmission fluid temperature. Since your mods will make the computer non-functional, you need to either hook up a manual switch to do that job, or get a retrofit switch kit from Summit or Jegs to do it for you.

 

sorry i meant to say 383.ok well i have another ? for u guys its kinda a crazy one.ok since the 305 and 350...i mean 383 the blocks are the same right,could i take my existing tpi setup and have somebody port the runners,plenumn and ill buy a aftermarket intake and have it mildy ported and get a bigger throttle body to the feed the motor more air would that work or would i be losing power by swapping to tpi??

 

The stock runners are the LAST parts you want to keep! An aftermarket base would make it easier, but both it and the plenum can be ported to work better. The runners, though, should be aftermarket, and a bigger TB makes sense.

Check the TPI board for posts about using TPI on 383's.