Thread: highest compression ratio on stock rods

Tweet

Originally Posted by BigRedTrucker

What is the highest compression you can go on stock rods? Just curious. If you *must* know, I'm thinking turning a 305 (cuz I got it) into an ethanol only (or e85) burner. I've got it in my truck and just need to get the pennies together to build the 355. This isn't a question of whether e-85 is a good idea or not, this is just for a possible low buck project to see if I can do it or not. I'll probably ending up making my own alcohol fuel for it. I'm thinking 12-13:1 compression and getting what else I need with ignition timing. Would cast iron heads be ok or would I have to coat them. What carbs would be good to use? I see edelbrock is making a new e-85 carb but with the budget in mind i may hit the swap meet for a used carb that could work. Thanks guys!

I would not even fart around with stock rods.
By the time you re-size the big hole,small hole,polish,shoot-peen-yes-you have to after you polish the beams,install ARP bolts etc.
I wold look into a set of the Scat I-beams.
We have run these on 1/2 mile stock car engines that turn 7,000 rpm's with zero failures.
If you look you should be able to buy these for less than $200.
Oh,if you are making your own alcohol the ATF might come knocking on your door.
One other thing to remember alcohol is very dry and you must always run upper-end cylinder lube with it.
Also you need to run your valve guides looser at least on the exhaust side.

Eric makes a good point. If you are going to spend a lot of money on stock rods, you would be better off with a set of aftermarket I-beams from Eagle or SCAT. You would be money ahead and have superior parts.

Originally Posted by erik erikson

I would not even fart around with stock rods.
By the time you re-size the big hole,small hole,polish,shoot-peen-yes-you have to after you polish the beams,install ARP bolts etc.
I wold look into a set of the Scat I-beams.
We have run these on 1/2 mile stock car engines that turn 7,000 rpm's with zero failures.
If you look you should be able to buy these for less than $200.
Oh,if you are making your own alcohol the ATF might come knocking on your door.
One other thing to remember alcohol is very dry and you must always run upper-end cylinder lube with it.
Also you need to run your valve guides looser at least on the exhaust side.

Hmm. If I plan on doing it the own alcohol, I may get the license and whatnot. I was kind of making this a cheap project, but few things pan out that way .

i think i read you have a 305 and want to make it a 355, that will require a 350 block @ .030 over bore. not even sure they make a 13-1 piston for a 305, and stock oem heads will not be a good choice for that compression. it would run but be very very restricted. probably would hurt the motor eventually also.

Noooooo. LOL. I have a 305 that I plan to pull out after I build a 350 for it (I've got the block and other stuff). The reason to go with a 305, is cuz I've got it and it wouldn't put a whole lot of power out of it. I could get some of the compression from milling, something to look it once I eventually get the engine out and mic'ed.

Thanks guys for the responses!

Originally Posted by BigRedTrucker

Hmm. If I plan on doing it the own alcohol, I may get the license and whatnot. I was kind of making this a cheap project, but few things pan out that way .




Noooooo. LOL. I have a 305 that I plan to pull out after I build a 350 for it (I've got the block and other stuff). The reason to go with a 305, is cuz I've got it and it wouldn't put a whole lot of power out of it. I could get some of the compression from milling, something to look it once I eventually get the engine out and mic'ed.

Thanks guys for the responses!

Don't forget you will need a different carb. or you will have to do heavy mods. on the one you have now to make it work right.