Valves hit pistons,update.
Thread Starter
10 Second Club
iTrader: (22)
Joined: Mar 2006
Posts: 3,677
Likes: 2
From: Northwest side of Chicago
Valves hit pistons,update. For anyone that was following my thread from a couple weeks ago.
https://ls1tech.com/forums/generation-iii-internal-engine/648868-valves-hit-pistons-help-me-figure-out-why.html
I sent the heads out,found out i only had 112 spring pressure due to no shims. We shimmed them for about 135 pounds,replaced 2 bent intake valves,milled the head only about .002 for smoothing purposes. All back together now with new cam. Sound just awesome. Isnt tuned yet so it surges and dies alot. Cant wait to get this thing on the dyno and more importantly to the track. Thanks for everyones help in this matter.
Go ls1tech.
Alex
All new mods in sig.
https://ls1tech.com/forums/generation-iii-internal-engine/648868-valves-hit-pistons-help-me-figure-out-why.html
I sent the heads out,found out i only had 112 spring pressure due to no shims. We shimmed them for about 135 pounds,replaced 2 bent intake valves,milled the head only about .002 for smoothing purposes. All back together now with new cam. Sound just awesome. Isnt tuned yet so it surges and dies alot. Cant wait to get this thing on the dyno and more importantly to the track. Thanks for everyones help in this matter.
Go ls1tech.
Alex
All new mods in sig.
Thread Starter
10 Second Club
iTrader: (22)
Joined: Mar 2006
Posts: 3,677
Likes: 2
From: Northwest side of Chicago
The machine shop "touched up" the valve job. They said it was totally fine but since they had all the valves out they more of less cleaned it up. I did a leakage test and compression and everything passed perfectly.
can anyone tell me what is shimming 
is it pushing the springs further down then locking them at a lower point on the stems of the valves .... or to shim is if they`re puting something like a spacer below the springs to compress the springs with the same locking place on the stem without the spacer..... pics of before and after shimming is great if available.
is it pushing the springs further down then locking them at a lower point on the stems of the valves .... or to shim is if they`re puting something like a spacer below the springs to compress the springs with the same locking place on the stem without the spacer..... pics of before and after shimming is great if available.
Originally Posted by Bader-X
can anyone tell me what is shimming
is it pushing the springs further down then locking them at a lower point on the stems of the valves .... or to shim is if they`re puting something like a spacer below the springs to compress the springs with the same locking place on the stem without the spacer..... pics of before and after shimming is great if available.
is it pushing the springs further down then locking them at a lower point on the stems of the valves .... or to shim is if they`re puting something like a spacer below the springs to compress the springs with the same locking place on the stem without the spacer..... pics of before and after shimming is great if available.
Ben T.
Trending Topics
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
Thread Starter
10 Second Club
iTrader: (22)
Joined: Mar 2006
Posts: 3,677
Likes: 2
From: Northwest side of Chicago
In my situation, not having the proper spring pressure did not effect me for about 6k. I was only revving to about 6300-6400rpm and it was fine. As soon as i did my m6 to a4 conversion i reved to about 6700rpm. A few times on the rev limiter due to a 2-3 shift issue is all it took. Lesson learned.
Thread Starter
10 Second Club
iTrader: (22)
Joined: Mar 2006
Posts: 3,677
Likes: 2
From: Northwest side of Chicago
Im going to take it easy on the dyno. Ramp up the rpms slowly to monitor for any valve floating. My tuner wants to set my shift points closer to 7k. I think im going to do about 6700-6800rpms.
Thread Starter
10 Second Club
iTrader: (22)
Joined: Mar 2006
Posts: 3,677
Likes: 2
From: Northwest side of Chicago
Yep learned that leason the hard way. Could have been alot worse. Here is a new sound clip with the new cam in sig.
http://video.google.com/videoplay?do...92109621033441
http://video.google.com/videoplay?do...92109621033441
