90000 miles, don't have a feeler gage that goes below 0.006, but checking with a straight edge I can tell it is almost flush. Had a shop rebuild the engine. (Mains 0.0027, rods 0.0023) When I saw how bad this TC was scored, I decided to replace it. Went for an ATP cover which gives me about 12PSI @900 RPM hot after HWY drive.. In gear about 10PSI.. ( with HV pump and booster plate installed) Acceleration is fine, about 40PSI @ 2500RPM.. Would like to get rid of that setup as I know about the cons. I know TA cover would be the best option, just don't like to throw things away
I would suggest rebuilt this cover. The atp cover can be machined poorly and with hi volume gears your only getting 10 at idle hot? Unless your cam bearings are shot the cover isn’t helping.
Most likely it's not the cam as the whole engine was rebuilt by a company. New camshaf,bearings, .020 over...
Pretty big oil clearances. If standard size I would get .001 undersized bearings. Your HV pump has a spacer not booster plate. You use the booster plate with the standard pump. Also helps to mod the oil pump cover with the hole or ground out spot.
t/c doesn't look bad to me. i've run worse looking. the big problem i found with the t/c is the dizzie fit near the top. the dizzie hole has stretched out and the dizzie now is a loose fit. had to build another t/c. then again, nobody is beating the 350 like me.
Hey guys, I drove the new engine with the setup I mentioned ( Melling HV pump + thrust plate, new ATP TC and 20w50 oil) for one summer, always being careful about not beating it when cold and always letting it warm up nicely . The winter break now gives me some time to think about what to do: - Leave it as it is due to crearances on the wide side( mains 0.00276, rods 0.00236) - rebuild the old original TC and run it with standard gears - get the TA TC +TA booster plate kit and pump shim kit My concern is damaging the front cam bearing or distributor gear/shaft on the long run. This car is a cruiser only, no racing or reving north of 4500 rpm intended. What do you think?
If your bearings are standard size you can replace with .001 under size to tighten up clearance. I have always had .001 to .0015 clearance and had 25-30 psi at warm idle with 10-30 oil. The extra hole in the oil pump in the KB instruction sheet above puts oil on both sides of the gears for better efficiency. The gears should stick up above the cover and .001-.002 clearance set by gasket thickness. Earl Brown does the extra oil hole on the Turbo V6 oil pump. How to build a front cover/oil pump - TurboBuicks.com
Actually, you can have both the HV pump and the plate. Why It's called a "booster" I am not sure. It's just a new wear surface for the bottom of the gears... Just to chime in on the question, I have this setup on my 350 car. I run 5-50 Mobil 1, and I have since immediately after rebuild break in. I have about 40k miles on the rebuilt engine. Distributer gear still looks good, car runs well. fingers crossed. I was unaware of the negativity about this setup until I joined this board (recently). My timing case came out of a wrecking yard (Flerury's) north of Seattle as I BROKE the original trying to remove it without finding the bolt under the oil filter (whoops). Live and learn I suppose. My car is also a driver and more of a cruiser than a racer. Although it's difficult to drive without putting your foot into it...
I would suggest measuring the old cover. It’s already off engine. Use stock gears. If you have a piece of glass(very flat/straight) place 1000 sand paper on it, go across with the filter housing. Get a smooth flat surface. Try to get .003-.004 pop up on gears. Bolt on housing. No shim. See if you have any bind. Check with dial indicator if you can assembled. If you feel it’s good, try it on engine. Change relief spring to 60 psi. It may be a white spring depending on kit you have.
I thought the OP confused the spacer with the plate. You need longer bolts with the plate. KB called it a booster plate probably because the mod for extra hole they specify.
The white 60PSI spring is already In. What I can not tell is how bad the scoring in the gear pockets is for oil pressure ( pics in first post)
It is in fact an additional plate that goes between spacer and oil pump cover housing. Melling calls it gear thrust plate and is a new surface for the gears on the top end, like Max pointed out. No idea if it increases pressure like TAs booster plate
I have put together worse scoring in pocket. Don’t forget most thrust is on the plate or housing. I believe it’s not too bad. I would clean up the flash in pocket outlet port, the drill job left a ridge. I would remove it. I have also drilled them out to 1/2 inch. No clue if it helps but I have done it.
I have a stock rebuilt cover from underdog, .002 rod/main and a fresh ground crank. 5-10psi (lumpy cam) hot idle after an hour on highway at 500rpm in gear, 20ish at 500rpm in gear idle driving around town, 70-80psi cold start, 60 hot highway. 10w30 vr1. Factory covers are the way to go.
That was my thinking in the first place. Just not sure if there will be an improvement with the slightly loose clearances. Don't have the experience to tell how much it affects oil pressure.