Bowtie block issues - Lateral-g Forums

TBART70 · #1 10-17-2016, 07:42 PM

This is going to be long.

Hello everybody, I have a 548 CI BBC, New Gen 5 Bowtie block, 4.600 bore, 4.125 stroke. I was with the engine builder every step of building this thing. It has a Straub Technologies custom Hydraulic Roller cam with Morel hydraulic lifters. On the dyno with a small intake and 850 carb it made 690 hp and 750 ft. lbs. torque.

It has been in the car for a year, but I have been chasing problems the whole time. On the dyno we had good oil pressure, 35 psi hot at idle, 65 at 6200 rpm. When I put it in the car it had 10 psi at hot idle and only 50psi at 6000 rpm. The Morel lifters were also very noisy. I pulled the engine and switched out the Billet Moroso pump for a Titan gerotor pump. When I put it back together I had 35 at hot idle and 70 at 6000. The lifters were still noisy and one collapsed. I put in a new set of Morels and still had a noisy valve train. About 2 months ago I took engine builder for a ride, he felt it was down on power, he asked me many times if I felt like it had 750 ft. lbs. I never answered him( it seemed low ). He also was not happy about the valve train noise, I had a feeling that it was on the verge of another collapsed lifter. He said park it until we could figure something out. I pulled it apart and put in a set of Crower solids, when I primed the motor the lifters seemed to have a lot of oil coming from the bottom of them, put it back together and fired it up. It sounded meaner and had more power. I did not drive that much, but the solids were quieter than the hydraulics. I don't know how much more power it could be making but the Holley EFI needs more time on the solids to learn. Problem is my oil pressure is down to 15 psi hot with the solids. They are a HIPPO type. I pulled it apart again and put in a set of Morel solid in number one cylinder because I thought it might be lifter bore clearance. Primed it again and had the same gush of oil. I looked with my scope and could see it was from the HIPPO not the lifter bore. I had an old set of non HIPPO and put it in #1 and there was much less oil flow. If I put in the whole set of old style non HIPPO, I bet my oil pressure would be fine. The issue is that I should be able to run the Hydraulics with no issue, but...... My bearing clearnce on the mains is .0024, rods were same. According to Straubs engine builder at Foxwell Motorsports, he feels that I have had an oiling problem since day 1. They use the Morel Hydraulics in tons of BBC's running high rpm. I have the recommended spring pressure for the Morel's @ 190lb on the seat, it never seamed to float the valves and it always revved quickly to 6200 rpm. Some where there is an oil leak in the motor. I have messed with the distributor depth and now I was thinking about putting O-rings on the distributor. I don't want to run solids but we did it to prove a point that the hydraulics were hurting power. Also my distributor gear seems to have a lot of wear. I have a SADI core cam with cast iron melanized distributor gear. I have been told the Titan pumps are notorious for beating up distributor and cam gears. I don't know if I should pull the motor and try to find if oil is coming out of somewhere it should not be, or if I should just band aid it and run it. Any suggestions would be great. Thanks, Tom.

69z · #2 10-19-2016, 03:19 PM

Hi Tom,
Wow, I sympathize with you situation. It is a long shot, assuming your builder has some experience, but you might take the time to check out the bypasses above the oil filter:

Like I said, a long shot….but you might find the problem.
Good Luck,
Bob

**GregWeld** · #3 10-24-2016, 06:10 PM

Wait ---- I'm confused. You had a hydraulic roller cam - or hydraulic cam - and now you're running solid lifters?? You know that's not right.... right?

Pull the pan and pull a couple caps... my guess is the clearance is all wrong.

Che70velle · #4 10-24-2016, 07:19 PM

I like my rods a little tighter than my mains. I try to go .002-.0022 on rods, and mains at .0024-.0026. As Mr. Weld said above, the solid lifters on a hydraulic core is a no no. I've successfully done it the other way, with hydraulic lifters on a solid core, but the opposite usually doesn't work long.
What weight oil are you running? Are you running roller cam bearings?

TBART70 · #5 02-09-2017, 08:42 AM

Hi all again. Been chasing oil pressure issues since day one. Went through 2 sets hydraulics and switched to solids, pin oiled first then non pin oiled to bring up oil pressure. Needless to say I pulled the motor due to a lot of metal in oil filter, and low oil pressure. The cam gear is wiped. Motor is getting redone. New cam, going from 108 LC to 110 LC. Hydraulic grind, solid Morel pin oiled lifters. Went with different cam company this time. Upping duration a touch, and lift on exhaust. Also doing 4/7 swap. It won't be installed as advanced as before. Will re-dyno with Carb like last time. Will have actual cam specs in a week or two. Trying to figure out what I need to do before it goes back in.

Went through the oil galley routing many times before it was put together. I will do it again to make sure.

Thanks,
Tom

TBART70 · #6 02-09-2017, 08:43 AM

Quote:

Originally Posted by Che70velle

I like my rods a little tighter than my mains. I try to go .002-.0022 on rods, and mains at .0024-.0026. As Mr. Weld said above, the solid lifters on a hydraulic core is a no no. I've successfully done it the other way, with hydraulic lifters on a solid core, but the opposite usually doesn't work long.
What weight oil are you running? Are you running roller cam bearings?

Running 10w/40 oil

Solid roller lifters on Hydraulic roller grind. Bullet cams is making my new cam, billet roller core, wearever gear, solid roller Morels .

Vegas69 · #7 02-12-2017, 03:42 PM

I'd block the oil filter bypass. All that wear you see is being pumped through your bearings when the engine is cold. I bet your main bearings are toast.

TBART70 · #8 02-12-2017, 05:41 PM

Quote:

Originally Posted by Vegas69

I'd block the oil filter bypass. All that wear you see is being pumped through your bearings when the engine is cold. I bet your main bearings are toast.

Main bearings are fine, bypass is plugged.

Vegas69 · #9 02-12-2017, 09:18 PM

That's good news.

Where you take the oil pressure reading also effects the perceived pressure. 15w50 would likely get you to 20 psi at idle and 60 at wot hot. That is plenty in my opinion.

TBART70 · #10 02-13-2017, 05:41 PM

I tried 15/50 didn't help. Pressure taken by three different gauges. Did some more checking, seems to be a distributor/intake height/oilpump and shaft issue.