misdemeanor

I thought the motor never really pulled on the top like it used to. I gave compression test had 2@ 110# 2@115# 1@125# 2@135# and one at 40#
Pulled motor and did leakage and all was coming out of intakes. Pulled heads and at valves looked warped to engine builder He threw one in valve grinder and it touches 3 sides of the valve they appear mushroomed.
The 3 piece copper head gaskets seemed a little darker between the cylinders they question that.
They are wondering if the engine got hot. It has not got even warm.
Any ideas????

I dont want to write a book but here is what it is:
I think 610 cu, merlin tall block with the 325 merlin cast heads slightly opened up. 8.9 cr. It was broke in on dyno and ran/ tuned safe. EMI Thunder long tail exaust wet. pipes under water at idle with turndowns. 32 or 34 degree total timing. never would go over 5000rpm.
Fresh water pump bypass kit with 160 degree thermostat never gets over 125 degrees also have a water dump before engine after oil cooler.
made 600hp at 4800 and 690 torque like at 4200 so I thought is was cammed small?
Not sure on cam but goung to check number but I think the below is it. It says dry exaust??

Comp Cams BBC Gen 4 & 5 Hydraulic Roller Camshaft Cam & Lifter Kit
295-112808K
Your Price:
$1,149.99
Quantity:
More Info
Comp Cams BBC Gen 4 & 5 Hydraulic Roller Camshaft Cam & Lifter Kit

Hydraulic Roller - Incredible Power gains for 510 CID + naturally aspirated or supercharged with dry tailpipes. Incredible mid-range and top end performance.

Duration in Degrees Lift with 1.7 Rocker Arms Lobe Sep. Angle
Advertised @ .050"
In. Ex. In. Ex. In. Ex.
292 298 242 248 .624 .638 114°

Black Baja

What brand water bypass is on the motor?

sutphen 30

the heads,,were the bought bare and valves installed?who's valve are they?
my bet,valve job was pooched.
as for your hp,,those heads are holding you back and the cam should have been bigger and more split.

misdemeanor

I think this bypass kit. The thermostat housing protects the fresh water from hitting the thermostat and bypasses to the manifolds.
Big Block Chevy Water Inlet Crossover Kit with Bypass
Big Block Chevy Water Inlet Crossover Kit with Bypass
620-300100
Your Price:
$289.99
Quantity:
More Info
Eliminate your power robbing circulating pump!
Constructed of 316L stainless steel.
One large 1" bypass hose for increased water volume.
Includes 142 degree thermostat.
Includes Crossover, Thermostat housing, 142 degree thermostat, hose with clamps, bolts & gaskets.

misdemeanor

So this was a rebuild on the current motor that I ran for 2 seasons previous and was damaged by a screw went down the carb. So it was completly bored valve job etc. They installed all 16 valves (will find out exact brand) I thought better springs. They were going to check spring pressures installed height on all valves. So are the heads not a good head they were opened up how much I cant tell you because I purchased the motor that way and it used to have a blower. I only had compression raised and ran a 1050 cfm quick fuel

misdemeanor

I think these are the heads 345 not 325?
orld Products 030630-2 - World Products Big Block Chevy Merlin III Cast Iron Cylinder Heads Details

Big Block Chevy Merlin III Cast Iron Rectangular-Port Cylinder Heads

GPM

Can you post pictures

misdemeanor

I will get some pictures tomorrow. Courious on this build not many chiming in. Is it that bad of a combo of components?

GPM

Hard to say without more info, were the valves pulled up in the head ?

SB

Like most builds, it could be better...but....a lot of 502's make that power (hp) with slightly smaller cams and same or tad less compression also.

That's 100 cid's less.

So.....I'm betting something was off from the get go. Possibly like S30 said......valve job not sealing....or........wrong spring psi.....or bad tuning ????? or bad ring/piston seal...or ???????