too much noise and too many leaks

-

rpmrich

Well-Known Member
Joined
Aug 1, 2006
Messages
58
Reaction score
0
Location
roberts wi
ok here we go. old engine build. standard bore 440. 1974 block. cast crank, flat tops. 140 in the hole. yep needed a flashlight to find them. 452 heads stock. with replacment springs, done before i got them, .20 steel shim head gasket. str14 cross ram. 509 4 speed grind. old one. worked good, nothing too special, cam went flat, yep wrong oil. my fault. took the engine out and apart. cleaned everything.
swapped the crank to a forged .swapped the pistons to trw 2265 domes ? not sure if i got the number right. 12 cc domes. only .50 in the hoe now.
516 heads 68 -70 cc they were cut. .20 tho steel head gasket. advanced motion cam solid. 584 lift, 256 dur at .50.. try y headers. same cross ram intake and went with roller rockers.. engine idles well. 1000 rpm. engine temp steady at 190 all the time. timing at 36 deg. oil pressure good at 40 psi hot. valve train noise is more than i like but with stanless steel rockers and the open intake i can understand the noise. ok low rpm med load like leaving a stop light the engine rattles like a diesel .. if i bring the rpms up the noise is gone . but it happens everytime. from a stand still or rolling and in all 4 gears. thinking detonation. retarted the timing all the way back to 20 deg total, noise is still there, running preumin fuel, , still there. added oct boost, noise still there, mixed a 50 /50 prem fuel and 110 racing fuel. ran worse . went back to prem fuel with oct boost. then i fouond where the head gasket has started to leak. i took the heads off. found no damage but some of the carbon was flacked off. (detention) figured. found both heads were leaking coolant and both side hhad popped the gaskets for the center cyls . ok thinking i need less compression. was going to go back to the 452,s but they need new valves and seals cut to work wit the cam. to much money needed there. what about going back with the 516's but going with a .60 head gasket ? a .20 is worth 4-5 cc then the .60 should be worth 12 to 18 more cc's according to the chry book the combo i had was high 12 to 13.5 comp. will adding 15 cc's bring me back to around 10.5 to 11? or what do yall think, this combo was used before for the early max wedge set ups
 
Did you have the engine rebalanced when you switched cranks?

Did you use a internally balanced balancer and converter that match the forged internally balanced crank as the cast crank is externally balanced?

If not the inbalance is shaking the engine apart
 
yes its been all rebalanced and yes it has all the matching parts for the forged crank. no abnormnal shaking and no miss's
 
I reckon you might want to have the block decked and the heads mill just enough to keep from blowing the gaskets. if you're getting any water into the cylinders it doesn't compress very good. use new head bolts or studs.
 
THat .509 is on a 108 LSA. Cam Motion (like several others) is using 110-112 LSA's (or even wider) where they should be 108 or even a little less.

When you push static compression up to the limit, LSA becomes a BIG deal.
 
Why are you using steel head gaskets? Composite are much more foregiving to heat cycles ans warping, steel will not flex. Composites are good up to 12 to 1 compression. Also steels don't generally last very long, used by reacers this isn't a problem because the heads are coming of fairly often. I don't know the specifics but steel gaskets require the mating surfaces to have acertain finish machined on them, different roughness.
 
That's interseting, all the BB's your saying? I never heard that before. I was thinking they would be same as smallblock.
 
I've got you at 13.5:1 right now and with a .060 gasket 12.0:1
 
-
Back
Top