Valve stem seals, Anybody go bowtie on these before? |
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Valve stem seals, Anybody go bowtie on these before? |
jwalters |
Jan 17 2005, 01:13 PM
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#1
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Sooo Close....... Group: Members Posts: 1,677 Joined: 14-May 04 From: Huntsville, AL Member No.: 2,068 Region Association: Europe |
(IMG:http://www.914world.com/bbs2/html/emoticons/unsure.gif) Had one of my heads apart--one intake valve out--and while rummaging thru all my pack-rat crap I came across one chevy intake PC seal. Soooo.......
I look at it and slide it on the valve stem--perfect fit!- (IMG:http://www.914world.com/bbs2/html/emoticons/unsure.gif) -just like the chevys I used to put these on--Sooooo...... I put it on the guide top--again, a perfect fit! (IMG:http://www.914world.com/bbs2/html/emoticons/unsure.gif) Soooooo.... I put the valve back into the guide and trial fit this seal again......Perfect fit! (IMG:http://www.914world.com/bbs2/html/emoticons/unsure.gif) Sooooo............ I leave it there and put the spring and retainer together and then compress the valve wayyyy past where stock would be--no fouling! Soooooo........ In my turbo motor I am building--these would be prudent,,,,No????? Any first hand experience running these before???? |
bondo |
Jan 17 2005, 01:16 PM
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#2
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Practicing my perpendicular parking Group: Members Posts: 4,277 Joined: 19-April 03 From: Los Osos, CA Member No.: 587 Region Association: Central California |
I think valves in an aircooled motor run significantly hotter.. could be a problem?
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type11969 |
Jan 17 2005, 01:33 PM
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#3
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Senior Member Group: Members Posts: 1,231 Joined: 2-December 03 From: Collingswood, NJ Member No.: 1,410 Region Association: North East States |
I know that t1s came with them stock.
what it means that VW chose to leave them off the t4 I don't know. |
Cap'n Krusty |
Jan 17 2005, 06:40 PM
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#4
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Cap'n Krusty Group: Members Posts: 10,794 Joined: 24-June 04 From: Santa Maria, CA Member No.: 2,246 Region Association: Central California |
Never seen a T4 with valve stem seals other than a little POS that looks like an injector o-ring. Never seen any on a T1, and I've been working on them since 1960. Howya gonna get oil to the stems with seals on 'em? The Cap'n
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Jake Raby |
Jan 17 2005, 07:09 PM
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#5
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Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
We don't run them unless we DLC coat the valves.
With DLC basically the valves could run with no oil and almost be okay! The stuff kills friction in its tracks! |
jwalters |
Jan 17 2005, 07:17 PM
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#6
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Sooo Close....... Group: Members Posts: 1,677 Joined: 14-May 04 From: Huntsville, AL Member No.: 2,068 Region Association: Europe |
(IMG:http://www.914world.com/bbs2/html/emoticons/huh.gif) well the guides are bronze?? ( looks more like brass, but straight brass would be wayyy too soft for any application of this sort)--just like what all the V-8 guys use--self lubricating-they never really have issues unless real out of the world valve lifts and side loads are used... throw swivel feet into the picture and even more side load is taken away... If not--they are the exact same diameter as the bronze ones in a chevy V8--could easily use those. ( Wonder if Porsche / VW ripped these off the shelf for ease? ) I know there are heat issues--but only really with the exhaust ones--those can be reamed for a little more tolerance stem to guide wise--this would prevent siezing-- I am just theorizing aloud---- I am sure someone here has actually done testing on this--it makes just too much sense..it would be too beneficial to keep the internal pressure rise at a minimum. Especially seeing as how most engines last only 80k-100k ( Hopped up that is) So if they would last up to this point..hmmmmmmm I also am up and up at the V8 guys using a vacuum pump to put about 14 inches of vacuum in the block--they have reported a HP rise of up to 35 more!!!! |
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jwalters |
Jan 17 2005, 07:29 PM
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#7
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Sooo Close....... Group: Members Posts: 1,677 Joined: 14-May 04 From: Huntsville, AL Member No.: 2,068 Region Association: Europe |
(IMG:http://www.914world.com/bbs2/html/emoticons/huh.gif) Jake, is that the stuff that is sprayed on pistons and the like and then baked in an oven to cure it??? Or is it a more involved process?? (IMG:http://www.914world.com/bbs2/html/emoticons/confused24.gif) |
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Jake Raby |
Jan 17 2005, 07:36 PM
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#8
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Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
Hell no!
All that home applied shit don't work... This is a VERY involved casiciam process.. http://www.aircooledtechnology.com/coatings_2.htm The parts you see in those pics cost 1128.00 to have coated! |
jwalters |
Jan 17 2005, 07:39 PM
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#9
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Sooo Close....... Group: Members Posts: 1,677 Joined: 14-May 04 From: Huntsville, AL Member No.: 2,068 Region Association: Europe |
(IMG:http://www.914world.com/bbs2/html/emoticons/ohmy.gif) HOLY SHIT!!! |
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Jake Raby |
Jan 17 2005, 08:17 PM
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#10
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Engine Surgeon Group: Members Posts: 9,398 Joined: 31-August 03 From: Lost Member No.: 1,095 Region Association: South East States |
From what I have seen so far its worth twice that in what it allows us to do!
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