toms93lx

i wouldnt go with the 347 it is to much for the length of the cylider ....it works but the 331 would be more solid........as far as kits go i am a trick flow believer ......i have it on mine and was going to go 331 but chose not to.......you shop the internet right and assemble the motor your self you could do it for around 5 grand not counting a tune.....i spend 4.5 on mine .....and i had block work done and got everything you could posably need ..just make sure you find a good machine shop to do the block but do a 331 its a safer stroke for that block if you want a 347 so bad you might as well try to find a 351 block and build that. ......trick flow is the way to go for the upper half.....if you have any doubt call trick flow and tell them what you want to get out of your motor and the tech guys there are cool ..........

you will need to take the stoker crank and ballancer new pistons and rings and bearings and block to the machinist to get them machined , cleaned and ballanced.......do not try to cut corners with the money when it comes to the block and this stuff ....as far as oil gap clearance ring gap and all that other stuff the manufactuare will have that info but a good machinist will .....might be a good idea to have the machinist put the short block to gether for you that way is not a worry .....

sn95_331_GT_ yellow

331+Fox Lake TF heads+solid roller+TF R series intake = hold the f*ck on...

primetime5.0

Tom it has been proven that 347s are just as reliable as 331s

mjr46

Tom that is flat out misinfo at its finest............despite what you may have read on the internet, the ole rod rationale argument is misinfo, there are SB chevies and BBC'S that carry a so called "worse rod rationale" than a SBF 347 AND HAVE GONE WELL OVER A 100K......what is key is who builds your stroker and how well they pay attention to detail, I run a 347 with no ill effects of the rod rationale argument and I spray it too. and if the rod ratio scares you of a 347 use a 331 rod/5.315 and 331piston and 3.4 throw on the crank

Mark O'Neal

I'll third that. I'll also add that we sell probably 500 347's for every 331.

The biggest issue is still...what are your intentions for this engine?

tinman

Forgot about the grinding on the bottom of the cylinder walls.
I used a template that I got from TMR in Riverside, CA for this.
Used a carbide burr in an air grinder and got it done in about 10 minutes.
BTW, I used a 1969 block that I had sonic tested, bored it .060 so I've got 352+ C.I.D. from it. Used a small mechanical roller, Fox Lake CNC Twisted wedge heads, Vic Jr intake and a small carb (650) double pumper with a 4500 converter thru a C-4. 4.30 gears and 28X10.00 Hoosiers. I run at 3200 foot elevation in the Arizona desert. NHRA corrected 10.95 and 125+ MPH in my '84 hatch GT.....

toms93lx

thats what everyone says where i am from about the 347. i know it works but been told 331 is the way to go. just saying guys i know you can build any motor solid but here in st louis i dont see many 347 not many 331 either lol just going by what some speed shops and machinists told me......i didnt stroke mine becouse the extra money involved.....

mjr46

yeah that's the problem, most them machine shop guys only regurgitate what they've read and not actually have run/done or are doing, you need to talk to someone who runs one, I have one customer who uses his 94 gt in a courier service, heaven knows why for gas reasons...lol, but he has over a 100k on his already.......I hear ya' on the extra cost part, I opted for a 306 in my 89 vert for such when money got tight, I had planned a 331 and was ready to order it, omly reason I was going 331 in it was I already have a 347 and wanted to compare the two

toms93lx

how you like the 306 .......and what gears you running.....i got 308 and it blows off the line but will start turning the tires over at around 3.5 grand

mjr46

I'm running 3.73's, and mine is a 5 spd, I love it, however, yours blows off the line cause the AOD has a 2.40 1st ratio vs a t-5 3.35 ratio, so you'd be better off with 4.10's a shift kit and a 3000-3500 stall to start with and a external trans cooler to lower heat build up and extend trans longevity