BBC Valve Springs qrestion

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Offroad good luck with the engine project. I am going through the same thing as I bought a ready to run 454 for $300. At that price I knew something was wrong so I just planned a rebuild and was amazed at the crap I saw upon dis-assembly. Heard a story this past weekend from an older man telling me about a shade tree mechanic that was going to fix a rod knock for $25. The engine did not knock when cranked but it broke a rod about 10 miles down the road. The so called mechanic had wrapped a cigarette paper around the crank. OUCH!!
 
Haha! Sorry Offroad, I didn't look at the date on the posting. Just realized it was 2 months old. Carry on!
 
Update

Well it’s been almost 3 months since I’ve had nothing on my plate except working on builds. So for the next 3 day’s….maybe 4, I’ll be getting all I can done on the Off Road Rolls and the 42 Chevy P.U. Plus I got a rear caliper rattle on my 06 Audi …..wth?

Valve spring update: First we got some retainers that fit right, but after installing one and checking the valve spring height, it was obvious the spring height would need to be re-set with the new retainers so I pulled the heads and sent them to the machine shop. While the heads were gone I decided maybe it was time to learn a thing or two about big blocks. I’ve been a small block guy for years after owning my last big block back in the 70’s. It was a 66 SS 396 Chevelle with a powerglide. I bought that car for 500 bucks. It was wicked fast with 12.5:1, cam and headers etc. The guy thought he’d blown it up. It had a bent push rod and was out of gas from a leak in the fuel line. I fixed it in front of his house and drove it away. Man was he ****ed. Anyway, I pulled the motor and sold it and the powerglide for 500 bucks. The car had quite a reputation around town so it was easy to do. Next, I dropped a 65 327 with 10.5:1, solid lifters, cam and a Holley 650 w/vac secondarys. I coupled it to a tight ratio 4 spd out of a 69 GTO. Last, I swapped out the ring and pinion for a 4:56.1. That car was great fun. It would barely do a 100 mph. But 10 to 60 mph it was one of the fastest, light to light on West Colfax. The next time I drove a big block, it was a 454 in a late 70’s Chevy truck…… what a pig, all that and 10 miles to the gallon, no wonder I never owned another……..Sorry I got side tracked.

So I followed the advice of all those above here at RRR and began to tear down the engine and take a look see. First thing I learned was it had open chamber heads, 781’s. Next it had .030” flat top pistons. Better than dished pistons I suppose, but none the less, 8.2:1 I guess. I spent some time looking for some closed chamber heads but they are getting hard to find for cheap, and if you do they need lots of work. So I kept my eyes open and found a set of 9.8:1 domed pistons complete with rings for less than 300 bucks.

Now I’ve known for years that when someone says it’s rebuilt…?……?... As it turns out, rebuilt in this case was bore .030”over, flat top pistons, RV cam and valve springs, fresh valve job, replace main and rod bearings, std. std. Change the freeze plugs but don’t bother with the cam bearings. Replace the oil pump and have your wife pick up a new timing chain when she’s at Safeway.

Our build is as follows: We kept the open Chamber heads as they were fresh, got .030” over domed pistons and a fresh hone on the cylinders. Turned the crank .010” / .010”, resized the rods, and balance the bottom end. New cam bearings and cam w/ hydraulic roller lifters, new push rods and true roller timing chain set. New valve springs, stainless roller rockers with new screw in studs and poly rocker locks.

So I gotta thank you guys for pushing me to check this motor out. I must admit it was tough on me because after I bought the damn thing I was really looking forward to getting behind the wheel and goin vroom vroom. Granted we didn’t go all the way with forged rotating assembly but, the desk top dyno says she’ll turn about 410 to 430 hp and as it was, it may have been 210 hp at best. I’m starting to like this big block stuff, HP is easy.
 

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