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  #1  
Old 07-09-2009, 08:01 PM
STeeL25T STeeL25T is offline
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Head work

Lets say non hypothetically that I'm rebuilding a motor for boost. I got my bottom end straighten out pretty well, on the heads I am still very uncertain. I haven't decided for sure about going with a custom cam grind yet or not but thats easy, I want to know what should be done when rebuilding these guys up for boost. I do not plan on reving any higher than stock, maybe 500 ish more so I do not want nor can I afford to swap out everything in it to a Toms/ Rally Bob non hydraulic conversion. I mean as in, would you pit in all new valves and springs or not. Seems like a no brainer but if it isn't necessary then I'd like to skip it and get on the road that much quicker.

If it should be done, does AWD change everything over because their site isn't real clear to me. I see that they mill and vacuum test them and put new seals on but do they do anything else?
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Old 07-09-2009, 08:09 PM
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SoCal LS-L SoCal LS-L is offline
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Re: Head work

Valves have to be changed..... turbo engines run quite hotter through the heads and will burn valves of incorrect composition. Im sure YT can specify more because im not certain where you can get them, or if compatible with the newer turbo 4's.
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  #3  
Old 07-09-2009, 08:12 PM
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redlightningsvx redlightningsvx is offline
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Re: Head work

Phastsvx could answer this. His is boosted and his motor is fairly stock I think.
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Old 07-09-2009, 08:19 PM
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Re: Head work

his engine and mine are totally stock. They will hold up but still restrict airflow esp in higher RPMS. Even big cams with stock length valves cannot stack up to the ability to get the bigger lift numbers.

Tom
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Old 07-10-2009, 07:24 AM
STeeL25T STeeL25T is offline
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Re: Head work

What I guess I'm saying is that I am aware there is nothing I can buy to upgade these peices other than brand new stock ones, is that nessessary or if the ones currently in mine are fine can I just roll with them. The few people I'm aware of that have boosted so far were not built and did not run the crazy boost I want to shoot for so I'm kind of pioneering here... Which sucks cause I'm a 'follow a guide' kind of guy

It may just be something I'll have to convert to later on down the road if it doesn't perform well.
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Old 07-10-2009, 10:11 AM
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Re: Head work

oddly enough, I'm struggling with this as well. :/
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  #7  
Old 07-10-2009, 10:39 AM
STeeL25T STeeL25T is offline
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Re: Head work

Quote:
Originally Posted by cozykat View Post
oddly enough, I'm struggling with this as well. :/
Exactly, cause were both building motors to be turbocharged and theres not a lot of info on this to go around. We know the parts aren't there, we don't know what the stock ones will handle, especially with 100,000 miles on them. We don't know if dumping 300 dollars in new valves plus whatever the rest costs will even be sufficient if we were to take the dive and do it.

I guess if you both keep it stock and whoever is done first blows up, the other will know to upgrade
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Old 07-10-2009, 07:05 PM
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TomsSVX TomsSVX is offline
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Re: Head work

The parts will work. Just not as well as I think you would want them to. If you invest enough in the bottom end, you would be wasteful not to spend some extra to get the top end of the engine to match...

Basically, the stock valves are restrictive because they cannot support the ideal lift and the srpings are too soft to support high RPMS ie, where your boost will likely be

TOm
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