:-) just home from the engine dyno.....
#62
Everything is looking good. Congrats! I had a similar setup (HP wise) in my other Coupe so you should expect better times when you get it all sorted out.
My car was a auto with 3.73 gears and I was running 9.80's @ 139 before I pulled it and went turbo with that car.
Here is a video:
My car was a auto with 3.73 gears and I was running 9.80's @ 139 before I pulled it and went turbo with that car.
Here is a video:
#63
I thought I'd update this thread as I had some problems, and I don't want other people to have this happen as well.
My Valve tips are wearing, and intake rockers are wearing as well.
This is definately caused by running (well) over .625" lift, and flirting with 400+lbs open spring pressure.
DO NOT RUN IN EXCESS OF THIS if you want your setup to live.
Lash caps,correcting rocker geometry(for lash caps) and/or a cam with less intake lift should solve my problem.
PS the stock rotating assy has survived 40-50 passes shifting at 78-8100 every time!
My Valve tips are wearing, and intake rockers are wearing as well.
This is definately caused by running (well) over .625" lift, and flirting with 400+lbs open spring pressure.
DO NOT RUN IN EXCESS OF THIS if you want your setup to live.
Lash caps,correcting rocker geometry(for lash caps) and/or a cam with less intake lift should solve my problem.
PS the stock rotating assy has survived 40-50 passes shifting at 78-8100 every time!
Last edited by 3pedals; 10-26-2012 at 10:24 PM.
#68
I thought I'd update this thread as I had some problems, and I don't want other people to have this happen as well.
My Valve tips are wearing, and intake rockers are wearing as well.
This is definately caused by running over .625" lift, and flirting with 400+lbs open spring pressure.
DO NOT RUN IN EXCESS OF THIS if you want your setup to live.
Lash caps, and a cam with less intake lift should solve my problem.
PS the stock rotating assy has survived 40-50 passes shifting at 78-8100 every time!
My Valve tips are wearing, and intake rockers are wearing as well.
This is definately caused by running over .625" lift, and flirting with 400+lbs open spring pressure.
DO NOT RUN IN EXCESS OF THIS if you want your setup to live.
Lash caps, and a cam with less intake lift should solve my problem.
PS the stock rotating assy has survived 40-50 passes shifting at 78-8100 every time!
I remember you posting you had 2 different PAC springs. The smaller of which is only 405 lbs open I believe. How do the exhaust valves and rocker tips look?
#69
#70
Valve springs are shimmed to .050" from coil bind at Max lift which has brought the full open pressure above 400lbs by alot.
PAC 1521 intake springs
PAC 1221 exhaust springs
Exhaust rockers are fine, valve tips have almost no wear, but there is some. Exhaust lobe has only .62somefhing lift
I did install ARP 2000 rod bolts - probably un necessary.
PAC 1521 intake springs
PAC 1221 exhaust springs
Exhaust rockers are fine, valve tips have almost no wear, but there is some. Exhaust lobe has only .62somefhing lift
I did install ARP 2000 rod bolts - probably un necessary.
#71
What were you referring to about adjusting valvetrain geometry for lash caps? Ive also given thought to shimming the rockers but am not really sure how to go about it? Any insite? Eric L
#72
Well, oem rocker geometry is good for cams up to .620ish lift. Once you use a lobe with more than that, the wear pattern on the tip of the valve will be too close to the exhaust side, and the rocker will be contacting on or close to the tip = bad.
The rocker fulcrum needs to be lowered to fix this. Using lash caps will do the same thing, without having to machine the stands. Then just shim the rocker stands up till the swipe pattern is centered.
Edit: too bad I learned this after the fact.
The rocker fulcrum needs to be lowered to fix this. Using lash caps will do the same thing, without having to machine the stands. Then just shim the rocker stands up till the swipe pattern is centered.
Edit: too bad I learned this after the fact.
Last edited by 3pedals; 11-01-2012 at 08:11 PM.
#74
That was my error, don't trust the hydro lifter, even when pumped up. Use a dial indicator on the tip of the rocker, with a checking spring in place. Then just cycle the rocker to the max lift of the cam, and check your pattern .
#75
I get what your saying. Our high spring pressure overcoves the oil pressure in the lifter, therefore skewing the results. Eric L
#76
This is the first time Ive heard of this kind of problem on LS1Tech. I did read an article in GM HiTech that stated going over around .575 on valve lift could create enough side pressure on the valve tips to wear the valve guides out prematurely ,but until now that was the only concern I had heard.
I even asked a tech at Compcams about it before I ordered my 607-621 lift LSR cam, and they said they had never heard of a problem like this, but if I was worried about it, a set of Jessel shaft rockers should ease my mind (and empty my billfold,LOL). I havent looked at my rockers or valve tips. Looks like maybe I should.
I even asked a tech at Compcams about it before I ordered my 607-621 lift LSR cam, and they said they had never heard of a problem like this, but if I was worried about it, a set of Jessel shaft rockers should ease my mind (and empty my billfold,LOL). I havent looked at my rockers or valve tips. Looks like maybe I should.
#77
I'm curious, did you change the pistons to flat tops then shave the heads .050 then change the gaskets to obtain 11 to 1 compression? Or did you keep the same stock pistons? I've recently purchased an LY6 motor but would like to have higher compression. I was thinking about having the block checked, either honing or machining it as necessary then just buying a set of flat top pistons with the grooves already machines in them for valve clearance. Just curious if that would get me to 10.5-11.1 compression without shaving 0.50 off the heads and changing the gasket thickness. Nice set up buy the way. My goal was to see if there was a build out there that could possibly obtain 500 rwhp on an lu6 without turbo or super charging it or adding a nitrous kit. Would love to hear it run!!!