any pump can fail ,my titan has taken a beating and never faltered not to say it cant.i think good oil pressure cold and bad hot is the answer its a leak somewhere if not the bearings then somewhere else.galley plugs,distributor,ect

We have had a modified rear main off of an iron motor for years that we can test pump pressure in a gallon can of regular motor oil.

It tests 75 psi, but the oil was at room temperature.

Might need to have an easy way to heat it up. Maybe a bracket on the top of the pan rails to hold the rear main and pump in the oil pan and use the pan heater?

David, check your private messages.

Good luck, regards Bob

Thanks, Bob!

We will check it out!

DG

Thanks to everyone for their suggestions!

Problem solved!

The motto for today:

“Trust, but verify!”

I ordered the -10 under main bearing and they shipped standard size.

We didn’t double check [our bad], so major oil “leak”.

Just to be sure we did sent the pump off to Titan for a review.

No place to race now, but at least we will have oil pressure!

[QUOTE]Originally posted by David Gerard:
I have been running drag race engines since the early 60’. TF, Comp, and now TD.

This one has me challenged!

Aluminum Brodix Big Duke BBC. Just went through a complete major rebuild with new sleeves, cam bearings, rod and main bearings, rings, etc.

On the motor stand: 75 psi oil pressure with a drill motor. [20-50 oil]
In the car: Initially 75 psi oil pressure and then over two minutes running, it slowly drops to 25-30 psi. If you rev the engine, it goes up to about 45 psi. Oil never got above 120 degrees!

Took motor out of car checked Titan pump, inspected everything, but didn’t dissemble motor. Just checked a rod bearing and it looked like it had never been run. Normal side clearance on rods. No “stuff” in the pan, filter, etc.

Ran the same routine as above and got the same results!

We will pull the engine again and start disassembly, but I’d like some ideas on what might be wrong!

HELP![/QUOTE

Was it rebuilt by a shop, or a home assembly?
If a home assembly were the clearances checked with a mic and dial bore gauge, Or just read some part numbers?
Have had bearings not even close, marked std, HX, and .001
That is why clearances need to be physically checked prior to assembly.
Crank needs to be confirmed as a specific size.

I dynoed a BBC years back that had the same symptoms, 75 cold, 25 after 1 pull.
Had std bearings marked as .010 as the crank was .010 under. Had about .011 clearance.

Had a big block Mopar that I ran std. rod bearings on a .010 under crank for 58 passes, by mistake naturally.
Had 70 PSI going down track and about 30 at idle with a HV Melling pump and 20-50 Kendall.
When I pulled it apart the rod bearings still looked like new.
After that I've never worried about a little extra bearing clearance.

And there you have it. Check, check, check.