350 to 454 questions

[kwmech]

Originally Posted by ShinyC10

Just out of curiosity, cause I hear it a lot about 700r4 trans being weak. Is it not possible to build a strong one or it just expensive to do it? I had this one built like 5 months ago and I told the guy I want to hold up to 500/500 and he said I shouldn’t have an issue with that. But I’ve always heard the 700r4 are just not stout transmissions…

Also, you have any issues with vacuum?

Issues with vacuum? Not that I recall. The engine installed was a crate 502. I've never had a 700 last no matter who built it or however 'beefed up' it was. I went through 3 of them in my Suburban in a span of 5 years. Stock 350 tbi engine with very mild towing thrown in here and there. 700s should never have been installed in trucks. Your 700 may 'hold up' some but it won't last say more than 40-50,000 miles. So that is my experience and i've been building automatics since the early 80s