Ok, I'm torn. I'm thinking of building stroker for my drag car, and I'm looking for opinions from people with experience with stroker 5.0 based engines. As I understand it, the 331 keeps the rings slightly lower, reduces blow by, and keeps the rings out of the wrist pin. Will that matter for a strip engine? Also, I'm considering a domed piston, which would bring my compression to 12:1. Would that kind of compression split a stock block. It is a early block (1969) which would give me an avantage. I figure that if I keep the rpm lower, shifting at 6500, would keep it together. I would expect at least a season (200 runs) before a rebuild. Any helpful input is appreciated. Thanks in advance.
347 or 331 ?
- Thread starter BMad
- Start date
Thank's, I spoke to him about buying that engine at one point because I thought that I blew my engine up. Turns out that I just poped a rocker off. It made the oil pressure look strange at idle. With open headers it sounded like a rod knock. Any how, that event got me thinking about keeping and stroking my engine. I see kits from $800.00 to $1,200 that with machine work I'm looking at less than $2,000 for a high 10 to a low 11 sec. engine. I'm just wondering if it's going to be a one hit glory grenade, or a relatively reliable race engine.
With my build, i did a 331, i have AFR 185 heads, Scat bottom and all forged internals, i did a mild 9:1 compresson because i also drive it on the streets, its a stock block, what ever engine you do, as long as it is built right, it wont be a 1 hit wonder, im spraying mine with a 125-150 shot of nitrous for the track and should be mid to high 10's on the track. With stock blocks, you will have a max of around 500 horse before you start having issue's with the block itself, as long as you dont plan on getting real high horsepower, you will be fine with either engine. My builder runs a 347 on a stock block, all TrickFlow stuff, he hit low 10's last year with only a 100 shot and he plans on running the engine again this year with no refresh, as long as its built right, there should be no worries
Safe isn't fun until you put ventilation holes in the block. 
If I had my way, I would be poking and stroking the 460 that's burning a hole on the concrete in my garage, but financial limitations pissed on those plans. I have a decent set of heads for the 302 right now, and with some port work they will do fine for now, so I'm not starting from scratch. The rod angle was another concern of mine. I've read that it might cause additional strain on the wrist pin, and cause the piston skirt to excessively drag on the wall. I was wondering if anyone actually encountered this personally. Again, thank's for the responses.
If I had my way, I would be poking and stroking the 460 that's burning a hole on the concrete in my garage, but financial limitations pissed on those plans. I have a decent set of heads for the 302 right now, and with some port work they will do fine for now, so I'm not starting from scratch. The rod angle was another concern of mine. I've read that it might cause additional strain on the wrist pin, and cause the piston skirt to excessively drag on the wall. I was wondering if anyone actually encountered this personally. Again, thank's for the responses.
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No experience with an issue, but this is why i stated the rod angle above. And why i went with a 331, say the mach shop does a shotty job on the bore work and the pistons skirts say hello to the walls (not good). Is it common Naaa but peace of mind is worth the 16 cu in.
BUT, in the end go with the best deal you can get 331 or 347.
BUT, in the end go with the best deal you can get 331 or 347.
Ive had both 3.25 and 3.40 stroke 8.2 deck engines.
They have that ring stuff worked out now.
When I first made the decision, I went with the "safe" route and chose 3.25.
The second time, I did it right. 3.40 stroke for me..... "oh and that 'rod angle past 6000k" statement.... Well I shift over 7500 with the 3.40 stroke engine and its STILL pulling.
They have that ring stuff worked out now.
When I first made the decision, I went with the "safe" route and chose 3.25.
The second time, I did it right.
3.40 stroke for me..... "oh and that 'rod angle past 6000k" statement.... Well I shift over 7500 with the 3.40 stroke engine and its STILL pulling.Wow, 7500 on a stock block? I wimper a little when I bump against the rev limiter that's set a 7000. You are not the first guy I spoke to that runs them up in that range. I guess my, and traditional thoughts on the limitations of the SBF are greatly exaggerated. This is a really informational thread.
Again I'm going to put this up. CHP CoastHighPreformance has fixed that old problem you guy keep talking about man. That's a thing of the past. THAT OIL BLOW OR WRIST PIN STUFF ON A 347 IS A DONE DEAL. LISTEN THE KITS COME WITH A 5.35 SIZE ROD. AND YOU GUYS KEEP ON WITH THIS. I HAD A 347 THAT I JUST SOLD LAST YEAR TO MIKE MORRILLO BOY. THAT HAD A STROKER FORGED KIT FROM CHP. WITH A 5.35 ROD AND THAT MOTOR IS HOLDING 24 POUNDS OF BOOST. RUNNING 9'S ALL DAY IN TEXAS. SO PLEASE STOP ALREADY WITH THE 331 IS BETTER THAT THE 347. THERE IS NO REPLACEMENT FOR DISPLACEMENT. THE 331 MAKE A LITTLE MORE TORQUE ON THE LOWER RPM RANGE. BUT THE 347 MAKE MORE POWER ON TOP. AND i've had alot of Fox Mustangs with strokers from 324 to 331 to 347 to now that I'm building a 363. So please if your not sure you know what your talking about. From experience then please don't post up nonsence. OH and I never use stock blocks. It's not a good look after 500 horsepower.