'88 700R4 questions??
Thread Starter
Cruising
Joined: Oct 2006
Posts: 13
Likes: 0
'88 700R4 questions??
i picked up a 700R4 trans from an '88 astro safari van and wanted to bolt up a 375-400HP 400ci. its only got 88,000 miles. will the stock trans handle this kind of power? or does it require slight modifications/add ons/rebuild? is this trans any different from the c4 vettes internally? what is recommended if at all necessary just incase i grenade the trans.. if i do upgrade the trans, how much will i be looking at in costs? i was hoping these transmissions were the same, from what i hear the 700R4 from a C4 have a high toleration for horsepower. if not, i was gonna throw a shift kit and what not.
thanks a lot
kalei
thanks a lot
kalei
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
Run a search on my user name. The differences between a vette trans and an Astro trans are huge. Cutting the output shaft down, moving the speedo drive gear, and swapping the c4 tailhousing on it will allow it to physically fit and bolt in. The internals are almost the same. Many pieces are identical, some are not.
Thread Starter
Cruising
Joined: Oct 2006
Posts: 13
Likes: 0
i forgot to mention this tranny was going in a 79 stepside and i planned on installing this cam http://store.summitracing.com/partde...0&autoview=sku to the 400. i was gonna add a 3k stall converter to match the 3.73 gears along with the cam. i figured the topic is close enough related to vettes since its a 700R and i do own a 94.
as far as cutting the output shaft, do i just send it to a machine shop and give em my specs? the trans in my truck now is a TH-350.
is there anything else i should do before i install the trans in the truck? from what i read, i can use the 350 driveshaft but will have to change the yoke? im not sure if its long or short tail..
btw, i didnt plan on making 375-400 horsepower right away. money is a concern for me and i am gradually increasing the horsepower stats on a timely basis.. but i do plan on dropping the 700R with the 400 in soon, the current engine is ready to seize...
as far as cutting the output shaft, do i just send it to a machine shop and give em my specs? the trans in my truck now is a TH-350.
is there anything else i should do before i install the trans in the truck? from what i read, i can use the 350 driveshaft but will have to change the yoke? im not sure if its long or short tail..
btw, i didnt plan on making 375-400 horsepower right away. money is a concern for me and i am gradually increasing the horsepower stats on a timely basis.. but i do plan on dropping the 700R with the 400 in soon, the current engine is ready to seize...
Race Director
Joined: Feb 2004
Posts: 12,518
Likes: 19
Originally Posted by 94C4_LT1
i forgot to mention this tranny was going in a 79 stepside and i planned on installing this cam http://store.summitracing.com/partde...0&autoview=sku to the 400. i was gonna add a 3k stall converter to match the 3.73 gears along with the cam. i figured the topic is close enough related to vettes since its a 700R and i do own a 94.
as far as cutting the output shaft, do i just send it to a machine shop and give em my specs? the trans in my truck now is a TH-350.
is there anything else i should do before i install the trans in the truck? from what i read, i can use the 350 driveshaft but will have to change the yoke? im not sure if its long or short tail..
btw, i didnt plan on making 375-400 horsepower right away. money is a concern for me and i am gradually increasing the horsepower stats on a timely basis.. but i do plan on dropping the 700R with the 400 in soon, the current engine is ready to seize...
as far as cutting the output shaft, do i just send it to a machine shop and give em my specs? the trans in my truck now is a TH-350.
is there anything else i should do before i install the trans in the truck? from what i read, i can use the 350 driveshaft but will have to change the yoke? im not sure if its long or short tail..
btw, i didnt plan on making 375-400 horsepower right away. money is a concern for me and i am gradually increasing the horsepower stats on a timely basis.. but i do plan on dropping the 700R with the 400 in soon, the current engine is ready to seize...
Thread Starter
Cruising
Joined: Oct 2006
Posts: 13
Likes: 0
thanks a lot, anything else i should add to the minimum? i was gonna have a shop install the shift kit and whatever else i need. i was gonna do all the easy **** myself, do whatever i can to conserve on money...
Le Mans Master
Joined: Apr 2005
Posts: 8,077
Likes: 4
From: Scarborough ONTARIO
My tranny built by pete k and he is guru in transmisions, but seems like u have 94 LT1 but 700R4 supports from 85-93 and there is lot diff after 93 700R4, make sure it fits ur 94 LT1 ask pete iam not sure though.
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