Badass Heads, Lost Power
11-12-2012, 07:55 PM
#41
Former Vendor
Not sure if it's possible Bill, but I would just put on the stock rockers and stands and redyno.
It won't cost much but it will answer alot of your questions.
The LSL lobe is a very nice lobe-but it will float-and the springs you have are pretty weak.
If that valve is not a hollow stem it weighs around 120 grams or more.
That's considered heavy.
It won't cost much but it will answer alot of your questions.
The LSL lobe is a very nice lobe-but it will float-and the springs you have are pretty weak.
If that valve is not a hollow stem it weighs around 120 grams or more.
That's considered heavy.
11-12-2012, 11:16 PM
#43
Le Mans Master
Thread Starter
Carl, I've heard two different numbers to not exceed, 165# and 185# and I personally know someone who has run multiple setups at 180# closed. Thats what I'm shooting for but I don't know if I'll get there before coil bind.
11-12-2012, 11:24 PM
#44
Former Vendor
The Ford guys have run as much as 500lbs on the seat on factory issue 87-95 hydraulic roller lifters-380 being where they settled on.
Look up "spintron testing".
Lots of valueable info.
11-12-2012, 11:28 PM
#45
Le Mans Master
Thread Starter
Arun,
I would like to revert back to stock valvetrain just to take a lot out of the equation but like I said, the holes that the rocker bolts go into have been enlarged to accomodate the Jesel stands. Just going to have to see if another ~15-20# of closed pressure is enough. If not maybe Morel lifters and stiffer springs. But if the heads need to come off to change the lifters I may just scrap the whole thing. Then again some 3" downpipes would take quite a bit of backpressure away.
I would like to revert back to stock valvetrain just to take a lot out of the equation but like I said, the holes that the rocker bolts go into have been enlarged to accomodate the Jesel stands. Just going to have to see if another ~15-20# of closed pressure is enough. If not maybe Morel lifters and stiffer springs. But if the heads need to come off to change the lifters I may just scrap the whole thing. Then again some 3" downpipes would take quite a bit of backpressure away.
11-12-2012, 11:50 PM
#46
Former Vendor
Arun,
I would like to revert back to stock valvetrain just to take a lot out of the equation but like I said, the holes that the rocker bolts go into have been enlarged to accomodate the Jesel stands. Just going to have to see if another ~15-20# of closed pressure is enough. If not maybe Morel lifters and stiffer springs. But if the heads need to come off to change the lifters I may just scrap the whole thing. Then again some 3" downpipes would take quite a bit of backpressure away.
I would like to revert back to stock valvetrain just to take a lot out of the equation but like I said, the holes that the rocker bolts go into have been enlarged to accomodate the Jesel stands. Just going to have to see if another ~15-20# of closed pressure is enough. If not maybe Morel lifters and stiffer springs. But if the heads need to come off to change the lifters I may just scrap the whole thing. Then again some 3" downpipes would take quite a bit of backpressure away.
Those heads are one of the best out there-the pocket dia should offer you alot of options.
11-12-2012, 11:57 PM
#47
Le Mans Master
Thread Starter
Yes homie, see page one for the dyno sheet with both gates and ~high boost. :P The valve float is hardly noticable on gates.
Yea they are cream of the crop as are the Jesels and I got both for a smoking deal. Would suck to have to yank them to change lifters. I'm confident the LS7 lifters can handle up to 180# but I don't see these springs getting that high. I guess a next step would be to find some stiffer springs if shimming these don't work. The pockets will accept a 1.5" spring (which is what is in there now) so it should not be a problem to find a spring of that diameter that has 180# at 1.800".
Yea they are cream of the crop as are the Jesels and I got both for a smoking deal. Would suck to have to yank them to change lifters. I'm confident the LS7 lifters can handle up to 180# but I don't see these springs getting that high. I guess a next step would be to find some stiffer springs if shimming these don't work. The pockets will accept a 1.5" spring (which is what is in there now) so it should not be a problem to find a spring of that diameter that has 180# at 1.800".
Last edited by 5 Liter Eater; 11-13-2012 at 12:00 AM.
11-13-2012, 12:26 AM
#48
Burning Brakes
Also keep in mind... the larger surface area of the bigger valves, combined with the added boost... will aggravate valve float if your springs are already borderline. (Pressure on backside of valve)
I ran into a very similar problem a few years ago on a Grand National engine at 30psi when I put more cylinder head on it. I ended up putting BBC springs on it to keep the valves from floating. Can't recall the seat/open pressures anymore... but it was far beyond what I was comfortable with. I was running a short duration/high lift cam.
Seems once you find enough spring to hold the valves closed... they start to beat up the hydraulic lifters.
Softer lobes or less lift may help.
I've even heard of some guys running solid lifters on billet hydraulic profiles @ .002-zero lash.
I ran into a very similar problem a few years ago on a Grand National engine at 30psi when I put more cylinder head on it. I ended up putting BBC springs on it to keep the valves from floating. Can't recall the seat/open pressures anymore... but it was far beyond what I was comfortable with. I was running a short duration/high lift cam.
Seems once you find enough spring to hold the valves closed... they start to beat up the hydraulic lifters.
Softer lobes or less lift may help.
I've even heard of some guys running solid lifters on billet hydraulic profiles @ .002-zero lash.
11-13-2012, 02:48 AM
#49
Drifting
How about some lighter valves? You could re-cut a cam with close to the same specs with lxl or xe lobes, etc. Lots of farting around I know and it's sort of killing the deal. If you need more seal room for shims you can trim the bottom of the seals if they have a lot of excess overhang at the bottom. I did this on my old heads that had .060" worth of shim under them and never had a problem for the last 15k.
12-30-2012, 10:13 PM
#50
Le Mans Master
Thread Starter
Just got done setting up the springs with offset keepers and shims. They were at 140# before at ~1.840", should be at 170# now at 1.760". That's as far as these springs can go without running into coil bind. It drives well but the only way to tell if the valve float is cured. Hope to do that soon.
12-31-2012, 06:59 AM
#53
Drifting
12-31-2012, 09:04 AM
#55
Le Mans Master
Thread Starter
12-31-2012, 10:04 PM
#57
Melting Slicks
Lies! See yall soon 
This time Ill be there early and buy the first round of drinks!
01-24-2013, 09:53 AM
#58
Rocker adjustment is a good point too. It's possible the pushrods are too long but its more likely the Jesel rockers are out of adjustment. I got them to zero lash and went another 1/2 turn on the rocker adjuster which is .040". So theoretically the lifters have .040" preload. The lifters were new and not pumped up so it was a little difficult to determine zero lash but I'm fairly confident I was within ~.010" and definitely on the loose side, so .040" - .050".
01-24-2013, 11:39 AM
#59
Le Mans Master
Thread Starter
The Jesel rockers look to be wiping perfectly. Can't really talk in relation to 1/4's of turns because I doubt the thread pitch on the adjuster nut is the same as a a stock LS rocker bolt. But I measured the Jesel adjuster nut pitch and by my calculations I'm preloading the lifter ~.040".
I used offset keepers and shims to get the springs up to 170# on the seat which is as much as they can go before coil bind. We'll see if thats enough when I get back onto the dyno.
I used offset keepers and shims to get the springs up to 170# on the seat which is as much as they can go before coil bind. We'll see if thats enough when I get back onto the dyno.
01-24-2013, 08:47 PM
#60
The Jesel rockers look to be wiping perfectly. Can't really talk in relation to 1/4's of turns because I doubt the thread pitch on the adjuster nut is the same as a a stock LS rocker bolt. But I measured the Jesel adjuster nut pitch and by my calculations I'm preloading the lifter ~.040".
I used offset keepers and shims to get the springs up to 170# on the seat which is as much as they can go before coil bind. We'll see if thats enough when I get back onto the dyno.
I used offset keepers and shims to get the springs up to 170# on the seat which is as much as they can go before coil bind. We'll see if thats enough when I get back onto the dyno.
Last edited by busaetr; 01-24-2013 at 08:50 PM.