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Engine rebuilding specs and balancing question.

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Old 08-03-2008, 03:02 PM
  #16  
Lizard928
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Adam,

I think I will definetly have to think about that.

And just to confirm this isnt a stroker crank, it is a 5.0L just having been drilled like a chevy.

Any chance you could get a quote for relapping the valves, checking the guides and getting the bottom end ready to go. I simply just dont have any time these days
Old 08-03-2008, 03:04 PM
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Oh and Adam, the ONLY shop in the lower mainland that really does any of this stuff wanted $1k just to regrind the valves and seats. Cost would go up should the guides need to be replaced etc.

As well know anyone in the area that does acid dipping of chassis? One shop locally does it and JUST to dip the tub, they wanted upwards of $10k. And no that does not include anything else, just the dip.
Old 08-03-2008, 03:36 PM
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Originally Posted by Lizard931

So Brendan what type of end gap are you running for your pistons?

I want to say the number 20. I have to look at my notes. But I think it was .20 to .22 of a millimeter.
Old 08-03-2008, 03:37 PM
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There is one remaining acid dipper down here in SoCal, and it was going to be like 2500, but that was 4 years ago.
Old 07-25-2009, 04:19 AM
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namasgt
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Im using the same 951 rings for my S4, I got the OEM ones with part # 08-323300-00. My question is do they need gapping ? some one told me they dont need gapping.
Brenden, were the rings in spec or you had to gap them ?
I never done this before, so please let me know what your experience was with these 951 rings.

Thanks in advance
AK
Old 07-25-2009, 05:12 AM
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AK,

If you will be running boost, I would open the ring gap up a slight amount. But the gaps will always need to be checked.
Old 07-25-2009, 05:36 AM
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Originally Posted by Lizard931
AK,

If you will be running boost, I would open the ring gap up a slight amount. But the gaps will always need to be checked.
I will check hem as soon as I find a good block, but are these rings supposed to be pre-gapped from the manufactor ?
I dont think I will boost any time soon if I decide to do.
Old 07-25-2009, 12:34 PM
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Originally Posted by namasgt
Im using the same 951 rings for my S4, I got the OEM ones with part # 08-323300-00. My question is do they need gapping ? some one told me they dont need gapping.
Brenden, were the rings in spec or you had to gap them ?
I never done this before, so please let me know what your experience was with these 951 rings.

Thanks in advance
AK
I relapped the bores on that engine - so the gaps were on the larger side from stock-new. I was happy - I did not have to gap.
Old 07-25-2009, 01:02 PM
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Fabio421
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Colin, try the 951 suppliers. I believe the heads are very similar and their stock valves are sodium filled.
Old 07-25-2009, 01:57 PM
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Fabio,
I am using S3 heads so I think that they are completely different.
Old 07-25-2009, 04:24 PM
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terry gt
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Colin , PRECISION in North Van decked my block for 175.00 sized the rods 14.50 each . Balanced the crank /rods / pistons/ flywheel/harmonic balancer for 280.00 Keeping in mind scat crank/oliverrods/968 pistons . the rods and pistons were already equal weight sets . Calico in N Carolina is coating the piston skirts and tops as well as the rod and main bearings . They will set up and assemble the short block for 500.00. I have talked to them about the heads , they can have valve seats made to their specs in 2-3 days as well as access to all the valves ect . Terry
Old 07-26-2009, 02:19 PM
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Can anyone tell me the stem diameter of the valves as well as the length? I found some TRW sodium filled exhaust valves that are the correct diameter but I don't know what to look for regarding the other dimensions.

Porsche TRW W0133-1615007 Exhaust Valve
(TRW - A4050-13414, W0133-1615007)
Price Range: $22.67 - $32.52 from 6 Sellers
Description: 2.0L (Sodium filled, 35.9x117mm).
Old 07-26-2009, 04:54 PM
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Originally Posted by Fabio421
Description: 2.0L (Sodium filled, 35.9x117mm).
Sounds like 931 valves. Likely will not work in 928 heads without mods.
Old 07-27-2009, 06:20 PM
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G'day Colin

I spoke to my engine shop guys. These guys are second generation performance engine builders, they were saying that sodium filled valves are rarely used these days, the only recent engine they were aware of, that uses them is the Nissan RB26DETT, apparently for aftermarket modified engines, the major aftermarket suppliers, Manley etc. use very high spec materials for extreme duty exhaust valves, without issues.

Hope this s of some value to you.

Cheers Roy
Old 07-27-2009, 06:26 PM
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Originally Posted by Roy928tt
G'day Colin

I spoke to my engine shop guys. These guys are second generation performance engine builders, they were saying that sodium filled valves are rarely used these days, the only recent engine they were aware of, that uses them is the Nissan RB26DETT, apparently for aftermarket modified engines, the major aftermarket suppliers, Manley etc. use very high spec materials for extreme duty exhaust valves, without issues.

Hope this s of some value to you.

Cheers Roy
The Z06 uses them:

"The LS7’s CNC-ported aluminum cylinder heads are designed to meet the high airflow demands of the engine’s 7.0-liter displacement. A hydraulic roller camshaft with 0.588/0.593-inch valve lift is used to allow plenty of air to circulate in and out of the engine. To ensure optimal, uninterrupted airflow, the LS7’s heads have straight, tunnel-like intake runners. Very large by production-vehicle standards – even racing standards – they are designed to maintain fast airflow velocity, providing excellent torque at low rpm and exhilarating horsepower at high rpm. The heads feature 70-cc combustion chambers that are fed by huge, 56-mm-diameter titanium intake valves. They are complemented by 41-mm sodium-filled exhaust valves."

Colin, check with TRW. They may have something if you can provide the dimensions. Once you get the dims. please post them here for others ( me ) to use. Here is an explanation of the valves from TRW themselves and it includes some info on the sodium filled exhaust valves. http://www.ms-motor-service.com/down...720_02_web.pdf



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