Is a 304 too big for an 8BA? I don't know the in's and outs of flatheads, I've just heard things from guys talking and me asking questions. I'm concerned about the block cracking between the pistons and heat issues, longevity of the engine, etc. I'm putting in a 400jr & 2x2 97's. It's going in a 31 roadster, probably driven with the hood off most of the time. I've heard a 286 might be the way to go I just don't know, so I though I'd ask you guys. Thanks
I think that 296ci is as big as you can feed and exhaust and that is with bigger valves a lot of porting and relief. 276 is much more practical,reliable and cheaper.
A 304 is possible using an 8BA block provided you have it sonic tested first. Ask to have it tested at multiple points on each cylinder as some are thinner at the top. The alternative is to sleeve the block ad then boring to 3 3/8" and using a 4 1/4" crank from Scat or Eagle. Posted using the Full Custom H.A.M.B. App!
Thanks. I'm sure there are some 304 HAMBers out there. I'd like to hear your thoughts. Given some of the issues with a large motor, I'm leaning towards 276-286. Thanks again for replying!
Whilst it can be done better to save yourself the grief and the cash and go with the smaller cubes My 2 cents
I run a 304 but its in the dragster and solid block, but I love the blown 5/16 x 4 in the ICT for a dialy driver and its on its 13th year after build.......
I run a 304 in a street roadster No problems with etc. But!!!! Have the block sonic tested first!!!!! Core shift can cause problems and wont allow for the big bore I would get a Scat 4 1/4 x 3 5/16 balanced kit . Makes 296ci You will have problems feed the 304 with two 97s A 296 might work A 284 will work , have a friend running the combo
I will probably get hell from some of these guys but why not look for a Lincoln motor instead. little there will go a long way.
My old T roadster ran a 276 and it ran really well. Never any big cooling problems or other flathead 'problems'.
Messing with flatheads, I think that the emphasis should not be cubes but transmission if you're talking about a street motor. Aim for a combo where 65 to 70 cruise is about 2400 to 2600 rpm. 2 cents.
Thanks for all the input. I'm going with a 8BA 276 2x2 with a 400jr... Posted using the Full Custom H.A.M.B. App!
If you do this, budget for heavy duty springs, helper springs, and coil-over shocks. These are HEAVY engines.
That's good to hear! I've never driven one, just heard them. A lot of research & opinions tell me it's the way to go. Should be on the road late spring. Can't wait! Posted using the Full Custom H.A.M.B. App!
A friend put together a 286 [3-3/8 x 4] with wiend cheater heads and tri power and 400jr cam..t5 and 3.08 rear gear..30/31 roadster..Really runs great, very eager with throttle response..Maybe not fast or quick but fun to drive!
I think a 3 5/16 bore x 4 stroke is probably the "Happiest "flat motor ... One with stock cam in a 3w 32 highboy 3.00:1 gears 39 trans. pulled good got 20mpg with 2- 97s.... Put a 400jr. In it ... car pulled hard... Mpg went down to about 14 .... But it sure sounded good ... I have a 3 3/8x 4 1/8 now with a 3/8 potvin cam runs real good but it doesn't like traffic a whole lot ... I would have been happier with a smaller bore... I'm not sure i can really notice the bigger stroke if you find a cheap orig. 4" merc crank ... I'd go that route... If your buying a new scat crank... Flip a coin I guess... I think I'd stick to 3 5/16 bore on a street car though
Big bore flatheads are kool, blown flatheads are way cooler, and not as pricey as you might think. Flatheads dont like to breathe - force feed em The difference ? Night and day. My 2c
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