HOW TO FIX LOW COMPRESSION. DIY RIDGE REAMER. THE OTHER GUYS PONTIAC TROPHY 4 CYLINDER. I BOUGHT A 1961 PONTIAC TROPHY 4 CYLINDER-IT DOESN’T RUN! CAN I FIX IT FOR THE DYNO? WHAT HAPPENS WEHN YOU HAVE NO COMPRESSION? TIME TO TAKE OUT THE BALL HONE AND VALVE GRINDING COMPOUND! WHAT ABOUT THE RIDGE AT THE TOP OF THE BORE? HOW TO USE A DIY RIDGE REAMER-AKA FLAPPER WHEEL! HOW TO LAP VALVES. CHECK OUT THIS VIDEO ON HOW TO GET A PONTIAC TROPHY 4 CYLINDER RUNNING FOR THE DYNO.
. N0 COMPRESSION, RICHIE REBUILD, WILL IT RUN?')){kind=link}
Worn camshaft, he said he checked the valve train but did not say if he checked the lift of the cam so I am not sure if this is correct.
Richard, I looked up the factory camshaft and valve spring specs from the 1961 AMA passenger car specifications package that Pontiac prepared. It is a teeny, tiny, baby cam. The valve spring seat pressure is 83 lbs @ 1.52", open pressure is 174 lbs @ 1.19". Cam specs are: Intake: Opens at 14 deg. BTC, Closes 58 deg. ABC, gross Duration is 252 deg. Max intake valve lift is 0.330".
Exhaust: Opens at 48 deg. BBC, Closes 24 deg ATC, gross duration is 252 deg. Gross Overlap is 38 deg. Max Exhaust valve lift is 0.330". The base 110hp Trophy 4 195 uses the same cam specs as the base 215hp 389 2 bbl engine.
I think we know why it was only built 3 years now, did you ck cam timing, are they new or known good plug wires.
Cool project man. But come on Richard, assembly lube is cheap.
Is the cam timing off? After seeing what you found on the rest of the previous owner rebuild, I am suspicious about every assembly adjustment.
Punch it 30 over and put an aftermarket head on it. Along with a custom intake and boost.
Are all cylinders running at same temp? Getting same amount of fuel? That intake looks aweful for fuel distribution. I’d bet a v8 manifold with the ports blocked off at the plenum and not end of runner wake it up
Richard, what are your cranking compression numbers?
When you were turning it over with the valve cover off the rockers were barely moving so I'm guessing worn cam and probably a couple collapsed lifters but even if you replace them I don't think that your going to gain a lot of power I'm guessing that it's the 110hp version of that motor
Cam lobes are probably flat
That ring ridge on those cylinders should have given it away that the block is really wore out and needs bore out. If you use a micrometer on the cylinders you will see they are tapered causing the bad dyno run. Rebuild the block with 60 over flat top pistons. Upgrade the cam. Use oil with zinc when breaking in the cam or expect to round it out. Would love to see it making at least 200hp but I doubt that intake will make it happen.
I'm going to say this quite Softly but I'd like to point out the WD-40 is not a lubricant. WD-40 is not a lubricant. WD-40 is not a goddamn lubricant. Please quit using it as such. You're going to use it on something that you will utterly destroy. And when you use a ball home you're supposed to go up and down quick enough to get at least a 30° crosshatch. 45 is better. WD-40 is a solvent and it's designed for displacing water from the ignition systems of deuce and a halfs during World War II to keep the trucks running during rainy weather.
That's the name water displacement formula number 40.
Given the probable mileage on that motor, 95 horsepower is respectable. Given the mileage on the motor, it probably could use a cam and it could use ring gaps that are narrower than the Grand Canyon. I recently had a General Motors LS engine apart, a 5.3 and every single ring in the engine had a .030 gap. Now let me ask you a really stupid question. Do you wonder why those engines drink oil. There is no purpose for that Gap being more than about .18???
Such weird and wonderfully wacky poncho tech.
I'd guess ignition is weak and random at rpm. I assume you used a known good coil and degreed the cam ? Chain slop is big
I could be wrong, but… judging by the size of the cap, the internals, cap and rotor for the distributor on an American Chevette gasoline engine should bolt-onto one meant for any V-8… including those for Pontiac models.
Also: I think a proper rebuild might be in order. Bore it 'til the taper is gone, Richard!
Don’t know what he expected from 60 year old engine.
Think I may still have ridge reamer. The ball hone didn’t remove ridge, it only hid it
It will run for a while with new rings but every time the piston goes up the cyl the rings expand(and wear)
Those 10 or 20 tho. Because of the wear.
Wanna guess how many miles it runs before it uses gobs of oil ?
About 10 to 20 thousand miles.
Wow, I though this was some fun oddball science project where you only used half the engine haha.
Cylinder taper
I'd try setting the valves while running. Just get the tapping quiet. There's probably more going on than that but you may see a difference.
Needs boost
Fire…….fire throw fire at it sorry on it