Author Topic: th350 rebuild kit?  (Read 1277 times)

Offline stevef

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th350 rebuild kit?
« on: June 12, 2022, 04:02:37 PM »
Since I have to rebuild my th350, as I mentioned below, what's a good kit? My car is a 79 TA, stock  403 engine with 185 hp and 320 ft/lb torque. Maybe a little more with the true dual exhaust, no cat. Edelbrock performer intake, that probably doesn't help other than weight savings, and a matching, mild Performer cam(off idle-5500 range). The trans came with a mild shift kit. Shifts are quicker but not hard. I won't be racing, just cruising. No stop light racing or burnouts. I see a multitude of kits on eBay. Any suggestions for a good brand that'll last, but not be overkill for my use? Thanks!

Offline Cliff Ruggles

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Re: th350 rebuild kit?
« Reply #1 on: June 13, 2022, 03:47:14 AM »
I don't do many transmissions these days so no longer use Transtar for parts.  There are PLENTY of kits on Ebay at rock bottom prices.  Look for complete kits that have frictions, steels, thrust washers, bushing (full set), band, filter, modulator, gaskets and seals.  I ALWAYS replace both sprags in a TH350 build no matter how good they look.  No need to opt for the hardened outer sprag race for what you are doing.

I'd recommend my book on the TH350 as well......Cliff

https://cliffshighperformance.com/product/gm-turbo-350-transmissions-how-to-rebuild-and-modify

Offline stevef

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Re: th350 rebuild kit?
« Reply #2 on: June 13, 2022, 07:19:52 AM »
Thanks for the great advice Cliff. Good to know about the sprags! Now I know what to look for. I bought your th350 book several years ago, and it's been helpful. I have your Q-jet book too by the way, and have bought about 6 carb kits from you over the last few years. Will buy more pretty soon. Thanks again. 

Offline 77cruiser

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Re: th350 rebuild kit?
« Reply #3 on: June 13, 2022, 08:16:59 PM »
Jim

Offline stevef

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Re: th350 rebuild kit?
« Reply #4 on: June 16, 2022, 01:10:25 PM »
Thanks Jim. I'll look at them.

Offline Cliff Ruggles

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Re: th350 rebuild kit?
« Reply #5 on: June 18, 2022, 06:44:55 PM »
Like the TH400 the "weak" spot in the TH350 is the intermediate sprag.  I prefer to install an aftermarket drum with the 36 element sprag upgrade for big power applications. 

I've tried a few times to skimp by just using the hardened outer race and stock type roller clutch and they just don't last behind high torque engines in racing applications.

I also like the bolt-in case saver set-up for the 4L60 with longer rollers. Most TH350 cases are worn some at the center support anyhow so that upgrade is a win-win all the way around.......

Offline tayto

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Re: th350 rebuild kit?
« Reply #6 on: June 18, 2022, 09:35:19 PM »
this style cliff?

Offline Cliff Ruggles

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Re: th350 rebuild kit?
« Reply #7 on: June 24, 2022, 07:19:34 AM »
Yes, that's what I use in them here....