LQ4 TH350 vs TH400

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Jun 13, 2018 | 02:50 PM

Mark30

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LQ4 TH350 vs TH400

What would be your choice between the two behind a stock lq4 in a GM A-body.

Jun 13, 2018 | 02:58 PM

Game ova

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Quote:

Originally Posted by Mark30

What would be your choice between the two behind a stock lq4 in a GM A-body.

400, because it would be future proof.

Jun 13, 2018 | 04:01 PM

MaroonMonsterLS1

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TH350 because around me cores are way cheaper and I can build a 500hp unit for about $150

Jun 13, 2018 | 04:40 PM

bbond105

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From: Poplarville, MS

TH350 because it is lighter.

Jun 13, 2018 | 06:41 PM

Tuskyz28

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From: Mississippi

350 is lighter but the 400 guts are beefier. Hard choice..... but I say 400 as well. A body cars are pretty heavy.

Jun 13, 2018 | 06:49 PM

Game ova

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Seriously doubt that the extra 15 pounds of the 400 will degrade performance. I'd rather have the durability, put it in and forget about it.

Jun 14, 2018 | 07:25 AM

MaroonMonsterLS1

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From: Iowa

Quote:

Originally Posted by Game ova

Seriously doubt that the extra 15 pounds of the 400 will degrade performance. I'd rather have the durability, put it in and forget about it.

a 400 is about 10-15 lbs heavier overall and 90% of that is rotating mass. But I agree...unless you are a class racer looking for every hundredth...it's not going to matter. For a stock LQ4, I would honestly go with whichever one you can find more cheaply. Around me, th350 cores are cheap and th400 cars are getting expensive.

Dual feed the directs
LEAVE the 1-2 accumulator alone
Block the 2-3 accumulator
Hardened Int. Roller clutch race
Shim PR Spring
Block the Low Control Valve Inboard
Drill the Separator Plate
You can block and loop the governer too, very easy, but that's only if you want full manual control

Do these things and you have a unit that will survive a long time at 500hp so long as you don't do a stupid burnout and explode the sprag.
These are super easy and very cheap to build.

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Jun 14, 2018 | 12:56 PM

MaroonMonsterLS1

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From: Iowa

Then you must not do a very good job building them then?
500 is pretty easy for a th350, so long as you can avoid blowing up the intermediate sprag

Jun 14, 2018 | 05:25 PM

#10

RPM WS6

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From: Schiller Park, ILL Member: #317

Quote:

Originally Posted by RockinWs6

...to make that 350 hold up @500hp good luck. Stock the 400 will take a hell of a beating, the 350 forget it. I've built 100s of both trust me on this.

I agree with @MaroonMonsterLS1 above. 500hp isn't beyond the limits of a proper TH350. Old/stock or poorly built ones could certainly be a different story.