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-   -   H-I-J '76 Nova re-fit. (https://classracer.com/classforum/showthread.php?t=67661)

Dissident 03-22-2019 11:26 PM
Re: H-I-J '76 Nova re-fit.
 
Todd,
Being a data kind of guy, I ran some quickie calculations for the potential flow (internal leaks) of the EDM lifters and the groove thing in the lifter bores. I used 50psi as that is the pressure number you mentioned.The EDM lifters will flow approx 0.0371gpm (each) at 50psi. The grooves in the lifter bores will flow approx 0.264gpm (each) at 50psi. Doesn't sound like much until you toss in each number times the 16 leak paths. Total flow at 50psi = 4.8176gpm! WOW.:eek:

At that rate of flow, 5qts (1.25gal) will cycle very quickly. The grooves themselves go through 4.224gpm so I suspect that is the major offender and caused the earlier ugly bearings. Seems like the grooves need to be rendered useless, but I suspect that your engine shop guys have already suggested that.


I realize that I might be full of soup in this assessment, but I think it is very close to the correct analysis.:cool:



Best of luck solving the problem.



Regards,
HB2:)
Dissident

Alan Nyhus 03-23-2019 08:14 AM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Dissident (Post 585584)
Todd,
Being a data kind of guy, I ran some quickie calculations for the potential flow (internal leaks) of the EDM lifters and the groove thing in the lifter bores. I used 50psi as that is the pressure number you mentioned.The EDM lifters will flow approx 0.0371gpm (each) at 50psi. The grooves in the lifter bores will flow approx 0.264gpm (each) at 50psi. Doesn't sound like much until you toss in each number times the 16 leak paths. Total flow at 50psi = 4.8176gpm! WOW.:eek:

At that rate of flow, 5qts (1.25gal) will cycle very quickly. The grooves themselves go through 4.224gpm so I suspect that is the major offender and caused the earlier ugly bearings.

Regards,HB2:)Dissident
Actually, I think your figures are pretty close. Lifter bore clearance is also a component. Todd mentioned that one of the lifter bores had two grooves in it. -Al

Rich Biebel 03-23-2019 09:32 AM
Re: H-I-J '76 Nova re-fit.
 
The correct solution to me, is one of two choices. Machine the lifter bores for bronze sleeves to eliminate the grooves and use the direct lube lifters. OR....Use the block as is and buy different lifters without the holes. Either option is gonna cost a good bit. Using restrictors is worth a try at this point.

Pat6868 03-23-2019 10:25 AM
Re: H-I-J '76 Nova re-fit.
 
Back to time proven basics is the way I would go, and it wont cost that much.

Hacksaw 03-23-2019 11:12 AM
Re: H-I-J '76 Nova re-fit.
 
Is there some way you can fill the slots in the lifter bores other than using bronze bushings? With todays chemicals, I would think there must be something that should work.

FED 387 03-23-2019 11:28 AM
Re: H-I-J '76 Nova re-fit.
 
I know you don't want to hear this but maybe its time to get another block and start over unless you want to do bronze bushings---not sure what your guy will charge you but doing 16 lifter bores in labor & the cost of the bushings can get kind of expensive---you will still have your rotating stuff and heads etc so all you are really doing is getting to the point where you have a straight good block to work from---you want to do any tricks you can always do that but there has to be a ton of good SBC blocks you can choose from and move forward on your project---as somebody suggested go back to the basics and go on from there---FED 387

Pat6868 03-23-2019 11:55 AM
Re: H-I-J '76 Nova re-fit.
 
That engine will live grooved bores and all. Pay attention to lifter bore diameter, push rod hole size, oil drain back, oil viscosity. Good quality solid lifters (no hole), quality standard volume, standard pressure pump. Good starter or back up engine. Put it together and have fun. Not gonna cost that much.

Jim Hanig 03-23-2019 02:48 PM
Re: H-I-J '76 Nova re-fit.
 
Just a though ,make sure the screw in plugs in the front are not in to deep, Center one .

Nmbr1GMfan 03-23-2019 06:24 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Dissident (Post 585584)
Todd,
Being a data kind of guy, I ran some quickie calculations for the potential flow (internal leaks) of the EDM lifters and the groove thing in the lifter bores. I used 50psi as that is the pressure number you mentioned.The EDM lifters will flow approx 0.0371gpm (each) at 50psi. The grooves in the lifter bores will flow approx 0.264gpm (each) at 50psi. Doesn't sound like much until you toss in each number times the 16 leak paths. Total flow at 50psi = 4.8176gpm! WOW.:eek:

At that rate of flow, 5qts (1.25gal) will cycle very quickly. The grooves themselves go through 4.224gpm so I suspect that is the major offender and caused the earlier ugly bearings. Seems like the grooves need to be rendered useless, but I suspect that your engine shop guys have already suggested that.


I realize that I might be full of soup in this assessment, but I think it is very close to the correct analysis.:cool:



Best of luck solving the problem.



Regards,
HB2:)
Dissident
This is an eye opener!

Nmbr1GMfan 03-23-2019 06:31 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by FED 387 (Post 585607)
I know you don't want to hear this but maybe its time to get another block and start over unless you want to do bronze bushings---not sure what your guy will charge you but doing 16 lifter bores in labor & the cost of the bushings can get kind of expensive---you will still have your rotating stuff and heads etc so all you are really doing is getting to the point where you have a straight good block to work from---you want to do any tricks you can always do that but there has to be a ton of good SBC blocks you can choose from and move forward on your project---as somebody suggested go back to the basics and go on from there---FED 387
The pistons and this block are pretty much junk without each other, so if I have to get a block I have to buy pistons and vice versa. IMO, It will be fine when I get the oiling straight, it ran before. I just need to make this reliable so I have a spare. When it runs I'll start with a Dart block and all new internals.

Nmbr1GMfan 03-23-2019 06:33 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Jim Hanig (Post 585619)
Just a though ,make sure the screw in plugs in the front are not in to deep, Center one .
Yes, they were checked carefully.

Nmbr1GMfan 03-23-2019 06:42 PM
Re: H-I-J '76 Nova re-fit.
 
It was nice to get away from the engine for a day (we'll be back to that tomorrow) Autumn and I went down to work on the car today. Although I may get hamered here for this kind of work, we had a nice afternoon cleaning the underneath/underhood of the car.
https://i.imgur.com/88F1f9Gh.jpg
https://i.imgur.com/seeRc6qh.jpg

Dissident 03-23-2019 07:08 PM
Re: H-I-J '76 Nova re-fit.
 
Todd,
Someone mentioned that the thing would live.....but recent history doesn't support that notion. If you were running on the dyno at 600rpm/sec and going from 4000 to 7500, that only takes 5.833 seconds at 300rpm/sec twice that time. SO, if you total the pulls in time, that is not a livable package.Normal lifter to bore clearances is where a normal leak occurs. If it is sloppy, as an example 0.002", that leakage is approx equal to a jet of about 0.058" diameter oer lifter bore/lifter and that is additional to the groove that somebody increased the leakage path with. That flow number would scare most folks.Not a good package at all. IF you had the block reamed and honed for larger lifters, it would probably take a 0.904" lifter to clean up the groove leak. Yeah, not legal, but might save the block but would cost for another set of lifters and the cost of increasing the lifter bores. BTW - all that leakage and resultant deluge drops right down on the rotating assembly and the windage losses go up exponentially with RPM.


The lifter/bore flow above is in excess of 8gpm!!!


Best of luck to you and Autumn. Hope you get to race soon.;)

Regards,
HB2:)
Dissident

Nmbr1GMfan 03-23-2019 07:20 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Dissident (Post 585641)
Todd,
Someone mentioned that the thing would live.....but recent history doesn't support that notion. If you were running on the dyno at 600rpm/sec and going from 4000 to 7500, that only takes 5.833 seconds at 300rpm/sec twice that time. SO, if you total the pulls in time, that is not a livable package.Normal lifter to bore clearances is where a normal leak occurs. If it is sloppy, as an example 0.002", that leakage is approx equal to a jet of about 0.058" diameter oer lifter bore/lifter and that is additional to the groove that somebody increased the leakage path with. That flow number would scare most folks.Not a good package at all. IF you had the block reamed and honed for larger lifters, it would probably take a 0.904" lifter to clean up the groove leak. Yeah, not legal, but might save the block but would cost for another set of lifters and the cost of increasing the lifter bores. BTW - all that leakage and resultant deluge drops right down on the rotating assembly and the windage losses go up exponentially with RPM.



Best of luck to you and Autumn. Hope you get to race soon.;)


Regards,
HB2:)
Dissident
In my mind, the only difference between then and now, is lifters. These lifters have two real differences from the old lifters, the oil flowing from the edm hole and the extra oil pumped to the top (which I believe is more than the edm hole flow). So if I restrict the oil so less goes to the top and I plug the edm holes (or get non edm lifters) that should get me back to square one. I could even add a hv pump for insurance. Thanks for the replies.

HP HUNTER 03-23-2019 07:40 PM
Re: H-I-J '76 Nova re-fit.
 
Do you have Trend lifters in this engine?

killintime6968 03-23-2019 11:46 PM
Re: H-I-J '76 Nova re-fit.
 
If you can get or borrow a set of clear plexiglass rocker covers to use when on the dyno it might also give you a visual perspective on whats going on.

Nmbr1GMfan 03-23-2019 11:47 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by HP HUNTER (Post 585644)
Do you have Trend lifters in this engine?
They're Bullets edm lifters. I don't know who manufactures them for Bullet.

Kenny McCoy 03-24-2019 02:04 AM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Nmbr1GMfan (Post 585642)
In my mind, the only difference between then and now, is lifters. These lifters have two real differences from the old lifters, the oil flowing from the edm hole and the extra oil pumped to the top (which I believe is more than the edm hole flow). So if I restrict the oil so less goes to the top and I plug the edm holes (or get non edm lifters) that should get me back to square one. I could even add a hv pump for insurance. Thanks for the replies.
Need way less oil up top then you think you do..

Dwight Southerland 03-24-2019 08:20 AM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Kenny McCoy (Post 585661)
Need way less oil up top then you think you do..
Especially with roller rocker arms.

Glenn Briglio 03-24-2019 09:10 AM
Re: H-I-J '76 Nova re-fit.
 
Might want to start with oil restrictors with .060 hole in them on engine stand and prime engine to see results up top.You can always make the hole bigger.

Nmbr1GMfan 03-24-2019 12:53 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Glenn Briglio (Post 585669)
Might want to start with oil restrictors with .060 hole in them on engine stand and prime engine to see results up top.You can always make the hole bigger.
That's the plan Glenn, thank you.

Kenny McCoy 03-24-2019 01:08 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Glenn Briglio (Post 585669)
Might want to start with oil restrictors with .060 hole in them on engine stand and prime engine to see results up top.You can always make the hole bigger.
I would start at .030 with thin oil

Dissident 03-24-2019 04:25 PM
Re: H-I-J '76 Nova re-fit.
 
Todd, Autumn, and those interested,:D
FWIW - All my calculations, estimates, and comments were based on the kinematic viscosity of hot (190F-200F) 30W oil. The leakage flow with lower kinematic viscosity would be higher numbers.;)


Being an oil patch brat, I have rather strong opinions against using 0W lubrication in engines as I was taught to err on the side of reliability. And I fully realize your experiences may vary, but you can't win if you don't finish.:cool:


Regards,
HB2:)
Dissident

Nmbr1GMfan 03-24-2019 04:59 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Dissident (Post 585699)
you can't win if you don't finish.:cool:
Or never get started :D:D:D Thanks for the insight.

Nmbr1GMfan 03-24-2019 09:24 PM
Re: H-I-J '76 Nova re-fit.
 
Spent a few hours scraping gaskets and cleaning parts today. Additionally, here's a picture of a piston with the Line2Line coating after some dyno time.
https://i.imgur.com/F6W9XWah.jpg
https://i.imgur.com/gNbAHtbh.jpg
https://i.imgur.com/ZwO40DOh.jpg

Bob Mulry 03-27-2019 08:16 PM
Re: H-I-J '76 Nova re-fit.
 
I'll just throw my 2 cents in.....

A few more points of internal engine oil leakage are the rod side clearance, if the rear main has had the split chamfered for more oiling to the thrust faces, cam bearing clearance, seal between the oil pump mounting surface and the cap, oil pump body to cover leakage and gear end play.....

Do you monitor the oil pressure at the front of the block or the rear?

A bad oil filter bypass valve doesn't vent to the pan it just bypasses the filter...

Nmbr1GMfan 03-28-2019 09:58 AM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Bob Mulry (Post 585898)
Do you monitor the oil pressure at the front of the block or the rear?
Rear. When I'm done I'll check it at both.

Nmbr1GMfan 03-28-2019 10:04 AM
Re: H-I-J '76 Nova re-fit.
 
Pistons are off and rods are ready to be checked.
https://i.imgur.com/zd2KsFZh.jpg
https://i.imgur.com/NdpwVN9h.jpg

Glenn Briglio 03-28-2019 12:23 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Nmbr1GMfan (Post 585926)
Pistons are off and rods are ready to be checked.
https://i.imgur.com/zd2KsFZh.jpg
https://i.imgur.com/NdpwVN9h.jpg
Are you doing this rebuild before those bottles were emptied..........j/k

Nmbr1GMfan 03-28-2019 06:06 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Glenn Briglio (Post 585933)
Are you doing this rebuild before those bottles were emptied..........j/k
After this deal, I'll be drinking for sure.

Nmbr1GMfan 04-06-2019 05:42 PM
Re: H-I-J '76 Nova re-fit.
 
Decided to get the tires mounted earlier this week. Cut the shock mount and got a thin nut for clearance with the rim, hard to see but now we have clearance. Rears are on for good, front is on to check backspace and they're way better than the old ones (I'll add both pics to see the difference in backspace). Now we have to swap the new front studs in and bolt the fronts on for good.
https://i.imgur.com/cqCZtvGh.jpg
https://i.imgur.com/5zvbApUh.jpg
Before: too far out.
https://i.imgur.com/GtlvB9Uh.jpg
After: nicely tucked.
https://i.imgur.com/i5hqoWkh.jpg
https://i.imgur.com/ltzJEoph.jpg
https://i.imgur.com/1eKqovFh.jpg
https://i.imgur.com/D88YgkKh.jpg
https://i.imgur.com/WYiLTSSh.jpg

Dave Gantz 04-06-2019 10:38 PM
Re: H-I-J '76 Nova re-fit.
 
How's the motor coming?

BTW, isn't it amazing that, with all the technology in this world, we have to buy tires that seem to have their lettering painted by a 2nd grade class? (Apologies to 2nd grade classes.)

Keith Bennett 04-06-2019 10:47 PM
Re: H-I-J '76 Nova re-fit.
 
Todd,
Did I see a bleeder screw on the bottom of the caliper?

Nmbr1GMfan 04-06-2019 11:13 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Dave Gantz (Post 586392)
How's the motor coming?

BTW, isn't it amazing that, with all the technology in this world, we have to buy tires that seem to have their lettering painted by a 2nd grade class? (Apologies to 2nd grade classes.)
Engine is coming along with the obvious BS setbacks... Like the bearings that come loose in a box totally destroyed. Funny I didn't even notice the lettering lol.
https://i.imgur.com/M5kxYUYh.jpg

Nmbr1GMfan 04-06-2019 11:15 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Keith Bennett (Post 586393)
Todd,
Did I see a bleeder screw on the bottom of the caliper?
Yes Keith, for whatever reason, they have bleeders top and bottom.

Keith Bennett 04-07-2019 08:24 PM
Re: H-I-J '76 Nova re-fit.
 
I guess so you can run them either side.
I never have had that nice of stuff.
You two are building a top notch ride...

Bob Mulry 04-08-2019 10:12 AM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Nmbr1GMfan (Post 586394)
Engine is coming along with the obvious BS setbacks... Like the bearings that come loose in a box totally destroyed. Funny I didn't even notice the lettering lol.
https://i.imgur.com/M5kxYUYh.jpg
I have NEVER seen bearings packaged and shippped like that...

Are you buying your parts on flea-bay??

Whose bearings are they??

Nmbr1GMfan 04-08-2019 12:58 PM
Re: H-I-J '76 Nova re-fit.
 
Quote:
Originally Posted by Bob Mulry (Post 586471)
I have NEVER seen bearings packaged and shippped like that...

Are you buying your parts on flea-bay??

Whose bearings are they??
Never seen them like this either. Came from https://www.atechmotorsports.com/

FED 387 04-08-2019 03:19 PM
Re: H-I-J '76 Nova re-fit.
 
Looks like A-Tech is a subsidiary of SUMMIT

FireSale 04-08-2019 10:19 PM
Re: H-I-J '76 Nova re-fit.
 
The "About" tab of that distributor says it's a global wholesale distributor of parts. If you bought the house brand you were putting genuine Chinese parts in your build. I do Ford, but I'll guess those are main bearings. I can't seem to be able to spend over $100 for King or Clevite bearings, so what powered your decision here? Bearings and rings are ultra stressed stuff and need to be top shelf.


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