.030 is not an issue. Remember the 383 Chevy is based on cutting a 400 crank .200 on the mains to fit the 350 block. And for circle track motors the common thing is to use the Honda 2.0 rod journal diameter down from the Chevy 2.100. Before affordable cranks we’re available this was done on stock cranks.
374 Olds 350 stroker build
- Thread starter olds307 and 403
- Start date
- Status
Good point, my other 330 crank, while .010" on the mains is cut to the smaller 2" sbc rod journals from the factory Olds size, 2.125" for extra stroke. The Honda size is actually 1.88" and guys have used that on the 330 crank for a 3.6" stroke. I am betting there isn't a lot of .010" or .020" bearings laying around either, everything is in short supply. What he is getting at is how the larger undersize bearings may be manufactured, not crank strength.
Mark's response to the bearing question was this.
"The shells get thicker as the undersize gets greater". If anything that should make it more stable than a smaller undersize bearing. After break in, I wonder how high I could rev this 358? It will probably be done at 5500 rpm, so probably setting my rev limiter on the Ignitor 3 module at 5500 rpm. With the much stronger light pistons, stiffer plus lighter and way stronger rods with ARP 2000 rod bolts and ARP main studs with a 330 forged crank, 7000 rpm should be easy peasy. I know a guy doing that with heavy Speedpro's and stock rods, running low 11's with his Olds 350. That should mean 9000 rpm should be possible, I don't have the guts for that.
"The shells get thicker as the undersize gets greater". If anything that should make it more stable than a smaller undersize bearing. After break in, I wonder how high I could rev this 358? It will probably be done at 5500 rpm, so probably setting my rev limiter on the Ignitor 3 module at 5500 rpm. With the much stronger light pistons, stiffer plus lighter and way stronger rods with ARP 2000 rod bolts and ARP main studs with a 330 forged crank, 7000 rpm should be easy peasy. I know a guy doing that with heavy Speedpro's and stock rods, running low 11's with his Olds 350. That should mean 9000 rpm should be possible, I don't have the guts for that.
Mark said he guy has .030" rod bearings, told him to ship them separately. FYI, Mark said replacing the balancer is good idea considering the minimal cost involved. I told him to send me one of reasonable price and quality.
Just check that the radius is good at the journals after the crank is cut.
Yeah, I will try out my new 2" to 3" digital micrometer to check their work.
FYI to us SBO guys, Mark talked to Clevite and King both had .030" rod bearings in stock. The had zero .030" main bearings in stock and don't plan on making anymore. The Federal Mogul Bi metal bearing is the only option in that oversize. Summit has .040" as special order through King on rod and main bearings but that could be a long wait, probably the same for .030" mains.
Oof.
Is this a bad time to suggest an LS swap? 😉
I am looking forward to seeing this built and running. As for the power curve/rev range - engine dyno it is the only way to baseline it beyond trial and error at the track or using an accurate accelerometer (ie. a Draggy).
Mike, I always appreciate your opinion. Like I said, it will be time for a new car and it won't be a GM product, if parts for the Oldsmobile V8 become unavailable. It will get tuned with a wideband and will see the track, hopefully next year.
You know I am just busting your chops. We are going through a difficult period in this hobby. You may want to double up on the hard to find parts now. I hope to be in your position one day trying to find bearings for an "obsolete" V8.
Perseverance, my friend - you got this.
- Status
Similar threads
