Well it looks like my Rayson project is taking another detour. Seems that I am going to have to build another motor for it. The 355 SBC I was planning on putting in the boat is ending up in my nephews pick up. Seems he ventilated the block on the truck coming home from work last week.
And since he's not making much money, has two small kids, and it's xmas, we figured he needed the motor more than I do.
So I'm going to be putting together another small block chevy for the boat. I was going to pull the other short block apart anyway and change the pistons, so it's not really that big of a deal. The pistons in this one will also need to be changed, way to much compression, It's over 12.5 :1 with small chamber heads.
If I remember correctly the compression I want to use is around 8.5 to 1 right?? Any suggestions as far as pistons, what to get or what to stay away from?? I know forged, but any particular manufacturer or PN??
I am still planning on using the Comp Cams 268 cam that was suggested. I am not going to run the small chamber 461 heads, but will use a set of 882 castings I have that have been mildly ported and are running stock size valves, 1.94 intake. If I remember correctly these casting have the larger chambers.
I figure the motor will never run at high RPM so why use heads that were set up for high rpm.
Can I use 1.6 roller rockers with this cam, or should I stay with 1.5's
Exhaust will be Indmar water cooled manifolds, they look like the better Mercruiser ones, and should flow a lot better than the logs would have.
Carb will be a single 4 barrel 650 cfm Holley on an old Wiand Stealth or Edelbrock I have.
Velvet drive is 1:1 and the Walters V drive is 1:1, I'm not sure what prop is on the boat, it's a 3 bladed one.
When I pulled the short block apart on Saturday I noticed that the crank journals will need to be cleaned up, maybe a .010 cut, the were standard.
I was wondering if it would be a better idea to pickup a stroker crank and make the motor a 383. Any problems running a 383 in a V drive?? Most of the cranks I see for 383's are cast, at least the inexpensive ones are. Will they hold up in a boat, or am I better off getting the forged 350 crank I have cut. Price will be real close either way. I am also concerned about have to run an externally balance crank. And longevity issues in a marine application??
Block is an early 70's truck block 4 bolt mains. It's already 0.030 over and the bores look really good, so I may just have it tanked, and put new cam bearings and freeze out plugs in it. It was align bored and decked on the last rebuild, right before it went into the chevelle, it was never driven far after that, just 1/4 mile at a time. :supp:
Sorry to bring this up again, but what do you guys think???
Thanks for the help!!!
Bob
You will be using flat top or dished pistons to get 8-8.5 to 1 comp ratio. Forged crank is always better, but if you are staying below 5000 rpm with low compression, cast is OK. 383 should be no problem for your application, and the extra torque down low will be a huge help. Just my 2 cents.
Bob, just pick up a stock 350 and bolt it in and go play it will last forever, you don't have a hot rod type boat!.. :smile:
Bob, just pick up a stock 350 and bolt it in and go play it will last forever, you don't have a hot rod type boat!.. :smile:
Art;
That's what this motor will be pretty much a stock 350.
I was just wondering if the strocker crank might be a good upgrade since I've got to have the crank cut anyway.
The difference in price between having my guy cut the old crank and a New cast stroker for the 383 combo is less than $50.00.
I just wasn't sure how a stroker will hold up in the boat. No problem in a car, but it won't run at 5000 rpm under load for an hour at a time in a car either.
I know enough to stay away from cast or hypereutectic pistons and will put good forged flat tops in the motor, and try to get between 8.5 - 9.0 - 1 compression.
If cash flow was better I'd just stick a vette crate motor in it
FYI
The media blast guy says he can strip the paint and it won't hurt the gel. He's going to strip the engine cover and then give me a price. If it's 300 - 400 we'll go that route, if not then it's paint stripper in the driveway come warm weather.
Thanks!
Bob
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