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stock 5.3 block, centric supercharger 12psi max
stock 862 heads (milled .005" "SUPPOSEDLY")
stock LS1 MLS head gaskets
Morel 5315 lifters, LS2 trays
Custom Cam motion 214/228 .561/.561 115.5 +4.5 cam (stock DIA "supposedly")
Copped 5/16" moly 7.4" pushrods
Stock rockers/bolts with straub bushing upgrade
Howard .600" lift behive springs
I started it up and got it to idle at 18,20,22,24* base timing and the timing changes nothing. Vacuum is lower than it should be at 13.2-13.6" (55-60kpa) and something doesn't seem right. IAC counts are in the 40-60 range at warmish idle and don't seem to be wrong. My stock cam idled smooth at 550rpms and made 19" no worries... Now i can get the new cam to idle around 650-750rpms but its moving around a bit.
I was told to run stock length pushrods as the .005 off the heads doesn't change the length at all really. I can't find any vacuum leaks and Ive swapped intakes and all new gaskets.... No real change vacuum checked everything and sprayed starting fluid and didn't hear any changes in idle. I'm tuning in open loop and adaptive idle is off... so I'm not getting any help from fuel or spark.
So I rotated the motor to TDC compression both intake/exhaust are closed. I pulled the rockers and got 0 lash and tightened the rocker bolt. I cam up with 1 full turn roughly on the intake and 7/8-1 full turn on the exhaust. Ive been reading the morels don't want more than .060" preload and 1 full turn puts me at .078" preload. So my pushrods are too long? That smidge of too much preload causing a very small vacuum leak? Should I be looking at 7.375" pushrods? At this point the $100 for pushrods isn't an issue as I've been throwing tons of time swapping and checking and trying to tune the motor to pull more vacuum and not getting anywhere. I know the pushrod length checker is more accurate but at the same time I can't get one quick enough so this method will have to do.
I used a 3/8" drive and got to what I think is 0 lash, then put the 3/8" drive facing 12 oclock, turned the wrench in one continuous turn and snug starts roughly 7/8 and can get to 1 turn without a full tq value.
Def not as much slop in those lifters as a stocker. I'd order 7.35 push rods from BTR for 99 shipped and be done. Can always make a push rod length checker real quick from a stocker to double check the math.
So I confirmed my measurements and they could be a smidge off.
I adjusted for zero lash and used a tq wrench to set preload. #1 intake got to a full turn before it clicked I would say it clicked right at 12 o'clock , not before. #1 exhaust clicked right at 1 o'clock about, alittle after the intake did. Both started at 12 o'clock. So the intake got 90% of a full turn before it was just bolt stretch and the exhaust got to 100% of a full turn before bolt stretch. That still puts me at more than .060 stretch. I called tick performance and they recommended I go with the 7.375 as it will put me in the .50-.53" preload range which .050 is recommended and will
keep the valve train quiet (car is only street driven, warm weather). If I went with the 7.350 it would have put me into the .025-.030 preload range which is too short they said. They also said the morel will take more than .060 preload and be fine but that I have too much. I figure the exhaust will use up the other .010 extra clearance on the lifters and put me around .060 preload.
I ordered me up some 7.375 manelys and hope that does the trick.
Thanks for the info forcefed86. I thought the 7.350 would have been too small and given me a noisy valvetrain which would drive me bonkers. The car is used Manely for short trips so getting to oil operating temp doesn't happen 50-70% of the time. Forcefed86 do u think the extra preload could have been my issue?
no it did not. Does that apply to LS motors or is that a generic setup for all engines?
Reason i I ask is that tick, Cospeed, BT etc all setup the lifters with different preloads. Most stick to the .050-.060 range and one does .040. So do I go for the 7.350 or the 7.375? Will the 7.350 cause too much noise?
That note came in the set a buddy installed on an LS.
they defer u to there dealers but I called straub tech and spoke with someone. Don't listen to that paper lol. He said optimum is .050-.060 and they have a .140" full travel. He said my .078 will work but not optimal... but can't say it's def my problem but it could be. Said to drop preload to .050-.060".
At least you got a definitive answer from a reliable source! FWIW the set we installed wasn’t loud at .035. Iron block alum head. I can’t imagine that’s your issue either, but having the “correct” length sure can’t hurt. Let us know if it fixes it.
Gotcha, glad that's working out for you. At least I know I could always go shorter if need be.
So what do u think the issue could be? Something is causing a 4-6" vacuum loss and I can't seem to find it. Since is from the TB to the heads I can't find any leaks. Sprayed injectors and intake with starting fluid with nothing. Timing doesn't seem to affect it and my IAC counts are in the 40-60 range. MAP is pretty steady at 55-60kpa.
I can only assume that the lifters are pumping up and causing the valves to hang open just a smidge causing a very small vacuum leak. Multiple that by 16 valves and your got a decent size vacuum leak.
Im pretty sure the cam was installed dot to dot and I got a pic to prove it. The dot moved alittle due to slack in the chain and I had to move the flexplate a smidge after to lock it up with a flexplate locking tool.
You are running aluminum head iron block so I would shoot for 5/8 turn before bolt stretch. Also 5315's have around .120 of travel so either way .060 should be fine. I doubt your valves are hanging open with your current p rods.
You are running aluminum head iron block so I would shoot for 5/8 turn before bolt stretch. Also 5315's have around .120 of travel so either way .060 should be fine. I doubt your valves are hanging open with your current p rods.
Ugh, so any ideas on what else it could be? Pushrods are coming today... perk of having Manely manufacturing in the same state.
If the cam was retarded or advanced when installed how would it behave? Or maybe the 4-6" I lost is just the amount it's going to make? But everyone says I should be making more vacuum.
Well guys got some bad or troubling news. New Manley pushrods showed up today and decided to measure them with a caliper to verify actual length. Got some very disturbing numbers. I'm actually quite upset that they produced this and sent them out. NOT ONE OF THEM MEASURED ACTUAL LENGTH! not to mention they were thinner than the stockers and the cospeed moly ones. Cospeed was dead on at 7.3965" length and 7.396" length and .3105 DIA with the two I pulled. The Manelys had a .016" swing between them and only had a .307 DIA. I'm glad I didn't put these in as i really didn't loose much preload at all.
weird thing is there was 3 sets of numbers different etched onto them. Theres the 0617 , 0717 and the 0417. I'm assuming they are batch numbers. The 0617 and 0417 had the closest to actual numbers and the 0617 was the worst which happened to be the majority.
When you ordered them, did you tell the rep that your measurements were "end to end" of the pushrod? Some companies go off different measurement criteria, so you're always supposed to specify "end to end as measured with calipers" so they know exactly how you measured.
04-11-2017, 10:32 AM
pushrod a smidge too long? 
