[TCSGTO]

- At bottom of my OP I included a link to car running ... damn those lifters are loud, is this typical w/ these?Or could they be out of adjustment?

M[/QUOTE]


Those are old limited travel hydraulics. They should be set at 0 to1/8 turn past zero lash. Even correctly adjusted they are can be a little noisier than standard lifters. The noise could be the pushrods hitting the head from using the 1.65’s.
Idle sounds good, just the right amount of chop. When I ran a RAIV in a 400 I remember it sounding more radical than that, but that was along time ago.

[steve25]

All 10 degree locks tells you is that the valvetrain is built with aftermarket retainers, instead of the factory 7 degree locks.

The aftermarket retainers will provide some .040" or more retainer to seal clearance in general.

[RAIIIJudge]

Thanks Fellas,

I'll be looking to see what rocker arm ratio is, if push rods are hitting heads and I'll run a compression test .. Hopefully I can figure out what size chamber is.

I'll also check spring's installed height.
Is there any best method to getting an accurate measurement w/ springs installed, heads on the car etc ?

M

[promptcritical]

That's a nice car. It sounds good too.

[dmac]

The only issue about running it as is- if it has no mechanical issues- is that gas today is not what it was in the past. Premium grade gas has gone from as high as 108 octane when the car was built to 91 or less today. Some of the may be due to the way octane is measured, but if the block was bored and the heads milled, you need to be sure. The compression test can tell you a lot. Back 40 years ago, I wanted over 200lbs of cranking compression- and now under 180 is the most I'd aim for with a standard headed car to be driven on the street, unless you have race gas close by.

[Stan Weiss]

Originally Posted by RAIIIJudge

Hello Friends,

I'm getting back to a very long-time-stalled restoration of a 69' RAIII Judge that I've had since 82'. Car needs quite a bit still and I'm coming at it from all angles. Here I'd like to address my game plan regarding motor which was rebuilt in 96' and can't have more than 2 to 5 hours of run time. Besides the typical Assembly Manuals and the Pontiac Performance 55 - 79' book, I've been pouring over posts here and on the GTO Forum.

Originally Posted by dmac

The only issue about running it as is- if it has no mechanical issues- is that gas today is not what it was in the past. Premium grade gas has gone from as high as 108 octane when the car was built to 91 or less today. Some of the may be due to the way octane is measured, but if the block was bored and the heads milled, you need to be sure. The compression test can tell you a lot. Back 40 years ago, I wanted over 200lbs of cranking compression- and now under 180 is the most I'd aim for with a standard headed car to be driven on the street, unless you have race gas close by.

The engine was rebuilt 24 years ago. Lets see what he gets when he does a cranking compression test.

Stan

[RAIIIJudge]

dmac, I'm bracing myself for this reality. I'm right outside of Boston so plenty of Sunoco, haven't looked yet for other high octane options.

Stan, Sounds ominous, could you elaborate? FWIW I've got 35 - 40 lbs oil pressure at idle when warm and 65 - 70 at higher RPMs.
After half an hour or so running, no blow by or any weirdness out of exhaust save for smoked acorn or two every few minutes ; )

I appreciate the input,
Mike

[Stan Weiss]

Originally Posted by RAIIIJudge

dmac, I'm bracing myself for this reality. I'm right outside of Boston so plenty of Sunoco, haven't looked yet for other high octane options.

Stan, Sounds ominous, could you elaborate? FWIW I've got 35 - 40 lbs oil pressure at idle when warm and 65 - 70 at higher RPMs.
After half an hour or so no blow by or any weirdness out of exhaust save for smoked acorns every few minutes ; ) Chipmunks are tenacious SOBs up north.

I appreciate the input,
Mike

Mike,
Sorry was not meant to be ominous. dmac talked about 40 years ago and 108 octane gas. I don't believe 24 years ago the engine was built that way. I would like to see the cranking compression numbers. But if I had to guess now I would give you better than 50 50 it will be OK on today's gas.

Stan

[RAIIIJudge]

I see what you meant now, Stan .. I hope you're right!
It's a drag the car's not right outside, Im totally chomping at the bit to be working on it.
Best,
M

[STEELCITYFIREBIRD]

I have a set of the small chamber 48’s that were and are going back on my 400.
CR works out to 11.3:1, ran well on 93 pump gas available here. Had an Old Crane # cam comparable to RA4 duration, 60919 Crower going back in this time around.
Explosion 💥 pull from 3 k up. Have 4.10 and a Super T10. First gear hard to shift out of quick enough. 🚀

[RAIIIJudge]

Happy "New Year" Fellas,

It's been 7 months since I started this thread and I hope this post finds everyone well and having come out of 2020 as unscathed as can be hoped! While we did get put through the ringer here, me and mine are safe, sound and looking forward to things returning to normal.

There hasn't been any follow ups here as due to the virus I wasn't able to visit my stepmom therefore I couldn't work on the Goat. Well .. I'm just back from three long days w/ the car where me, my brother and a car load of parts I've been gathering for the past months made some real progress! Unfortunately and unexpectantly, as it relates to the nearly 25 year old, "fresh" rebuild, I'm afraid things haven't turned out as I had hoped but more on that in a minute.

I learned for certain that the rockers installed are Comp. Cams H1452 1.65 rollers and that push rods are Lunati 82726, stock length. I wasn't able to figure out what exact springs were used but I was able to measure from <surface of head> to where spring meets retainer and it came out to an install height of 1.722" (prolly 1.722+ since I didn't measure down into spring seat). I was not able to identify (4 spd) #48 head's chamber size but maybe compression results forthcoming will? I could <not> identify any clearance issues as a result of 1.65 rockers, all pushrods seem intact and true. Only indications of use on pushrods was some discoloration where they sit in the stock Pontiac push rod guides.

Here's where things get ugly. I ran a leak down test on engine w/ an new OTC unit. Passenger side cylinders at 75psi and drivers at 100psi. I hoped results might be different so I re did driver's side at 100. Since they weren't I didn't bother to redo passenger side. I then did a cranking compression test ( 7 revolutions each cylinder). I did not perform a wet compression test as I didn't become aware of such a test till last night ha. These were results:

Cylinder/ Leak Down Results/ Compression Results
1 16% 160 psi
3 18 190
5* 16 165
7 23 160

2 12% 170 psi
4 10 182
6 13 180
8 14 175

When running LD test each cylinder "sounded" <the same> but it was difficult for me to identify where leak was occurring. It was definitely not via radiator bubbles and when I placed an ear close to PVC opening or carb, it really didn't seem to be coming from either. Sound seemed to be coming from lower part of engine and when I cupped my ear to exhaust pipe I could in fact faintly hear leak.

* <no> idea what this tidbit means but when I ran leak down on cyl. 5 initially at 75 psi I got a reading of 30%. On pass where I re-ran that bank at 100 psi, cyl. 5 suddenly and regularly started reading 16%

I put a vacuum gauge on manifold and got a steady low reading of 12 hg. When I quickly revved motor reading zero'd and bounced back high. Yay ; )

When engine's fully warm there's no blow by. If I aggressively rev motor you can see a little smoke out the exhaust. I'll include a link to a video clip illustrating this.

It seems some test results are pointing to exhaust valves while other's to cylinder walls and rings? Either way I think what's occurred is the result of an improperly, long stored engine being hastily and too infrequently brought back to life. Don't mean to be dramatic, just realistic : ) I'm bringing this all to y'all's attention to update and punctuate this old thread and in hopes I'll learn a ton from any responses!

Sorry to ramble! Game plan on my end is still to bust my arse from here out and get. car. finished and on the road! There I think I'll see even more clearly where I am with this motor and if need be start to think about pulling it, seeing what I can re-use and doing a rebuild.

Really looking forward to any feedback and thank you!
Mike

https://www.dropbox.com/s/eyg3t7yu49..._8087.MOV?dl=0

[NeighborsComplaint]

You may have some light rust in between the valves and seats. I would run it and drain the oil a few times and see if it cleans up. The valves will rotate and reseat themselves when running.

[RAIIIJudge]

Thanks for comeback, N'sC, wasn't sure this thing was on ; )

Scenario you're describing is what I'm hoping will occur too .. I'll be up at vehicle in two weeks again, will run motor and do an oil change.

Is it safe assuming since one cylinder is up at 190 psi that that's where others should be? Don't know if you've read this whole thread but this is a <long> stalled restoration w/ many details on engine rebuild not known to me. If my memory serves my dad put 11.5:1 pistons in car.

Mike

[NeighborsComplaint]

180 +/- 5%