lost power couple weeks ago on a club weekend away trip
felt like somebody had stuffed potato's up my exhaust pipes, not uncommon with the vette club i hang around with
felt flat and had a funny drone to it
got it home and left it with a mechanic mate, he rings couple days later with the news......



that's what i found when i pulled the motor and stripped it down, #7 exhaust lobe missing
most others were showing sign of wear also, but i guess 41yrs of it
350 block still std bore, no ridge wear, original std bearings, we dont think that it's ever been out of the car

had been running Castrol GTX 20W-50 oil for older cars

rebuild will be just a mild build due to my strict historic registration rules.
350 auto, 3.08 rear, even still had the smog pump on it when i got the car, numbers match
going 30tho over, performer manifold, linish the crank,
have a set of 186 fuelie heads to bump the compression up (and to keep the very stock look i have to have)
want to run around 9.8-10:1 comp so i can run the mid level fuel we have down here

thinking bout a hyd roller for a cam tho, depends on $$ available

 

THAT should put some pep into the engine!

 

http://www.ebay.com/itm/HOWARDS-CAMS-CHEVY-SBC-272-278-510-525-RETRO-FIT-HYD-ROLLER-CAMSHAFT-KIT-350-/181164942094?pt=Motors_Car_Truck_Parts_Accessories&hash=item2a2e45a30e&vxp=mtr
Rebuild short block with 12 CC dish pistons and Felpro 1094 head gasket (9.6 to 1), 2000 stall convertor. Will be sweet and run on midrange fuel.

 

thanks mako for the cam info

will that cam still give me good vacuum for brakes/lights/wiper door?
dont want/karnt have a lumpy lumpy idle either, just a nice above stock sound would be nice.

this is just a weekend cruiser, and an occasional spirited driver

nothing much will hap'n this side of xmas due to my builder/machine shops closing for the hol's.

 

Excellent vacuum and slight lope at idle. That 112 LSA with the duration numbers will sound close to stock, good vacuum, wide powerband with solid low and midrange power and pull to redline. With your 3.08, auto, iron heads and fuel availability you don't want more compression or cam than this combo will give you and it will meet your needs well. The original 72 corvette TH400 came with a 2000 RPM convertor.

 

I have two rookie questions:

I'm wondering what an excellent vacuum reading would be to you? (my 350 carbed SBC idles @ 20 "lbs"/16 "lbs" @ 70 mph)

Were dish pistons standard in that year engine....or is that a way to keep the compression from increasing too much for mid-range gasoline when using the aftermarket cam?

 

how much wear on the pistons ,cranks and bearings ?whats the bore diameter at ? if the engine is in good condition ,maybe consider a cam swap only .you could break the new cam in on a dyno or a test stand .check out the oils in the sticky about oils .consider long slot rockers if you go with a flat tappet cam.

 

About 16 hg @ idle, plenty to run accessories. Dish pistons were standard but they had bigger dish. 12 CC is common and readily available. The combination gets your compression, gearing, cam and heads matched up to meet the needs and fuel availability. Here is a complete kit that you would grind the crank -.010 on rods and mains, recondition the rods, internally balance and use this combined with the cam kit for all you need to complete. I would also replace rod bolts, head bolts and use main studs. http://www.summitracing.com/parts/fe...make/chevrolet

 

It is a 40+ year old engine that has never been apart and had metal filings and debris running through it for quite a while looking at that lobe. How do you get the filings out of the nooks, crannies and oil galleries? Time for a rebuild. I wiped a cam on my 5000 mile recently rebuilt fully forged 302, caught it right away, and the bearings were junk, forged crank was trashed, bores all scratched up. Scrap because it was already .030 over from the rebuild.

 

That kit is about $100 less than the Comp kit I installed. Also, very good vacuum; about identical vacuum to the Crane Energizer I had in it before. Very satisfied with the performance results. VERY streetable manners.