Ok, so i installed my magic stick 4 into my 2001 LS1 vette engine. 241 casting heads and for some reason it came with LS6 vavle springs. Anyways the cam install went well with PRC dual vavle springs ti retainers, and harden Pushrods. So i go to start turning it (using a half inch breaker bar on an old crank bolt) to make sure that everything moves smooth and everything was going well until i hit one point when the engine didnt seem to want to move as smoothly. i marked that point on the crank bolt and continued to turn it (after a second it got easy to turn again) then it was smooth until it it got hard again. about 400 degree's after where it stopped last time.

Cliff notes:

-turns smoothly once and a while, but randomly doesnt want to turn at certin points. Let rest for a few seconds, becomes easy again.

-No spark plugs in holes so its not building compression

- Checked to make sure the dots were lined up before i took off or put back in the cam

-Used front crank bolt to turn engine.

Any ideas if this it happening normally or if the hydrolic lifter is just colapsing and then it becomes easy to turn again since the pressure is releasd from the lifter? I dont know but i dont want to start the engine until I am sure that I will no bend vavles or worst.

 

are u certain the pushrods are the right length? that sure does sound like PtV issues to me

 

I am pretty sure they are the right length. Stock which is 7.400 got all of the stuff from texas speed so I would hope they would send thr right stuff...lol But yes they are the stock size pushrods.

 

Texas Speed PR's have the lengnth on them. Are you 100% the dots are lined up? It took me an hour to line them up. I lined it up, then put it 1 tooth off both ways to make sure it was lined up correctly.
TSP says that you can run the MS4 with stock heads w/o p2v issues.

 

I know you probably don't want to hear this, but I'd tear it down to check the dot to dot if I were you. Better to take an extra 2 hours or so to be absolutely sure than to start her up right now and possibly have a few bent valves.

 

I agree /\ /\ You will be better off doing that instead of running the car a messing something up.

 

OH I forgot to mention how I did mine: with a Vette you have more room in front the engine. So I crawled in the engine compartment, sat right in front the timing gears and lined it up. It looked to me like it would be too hard to line the dots from the top of the engine so that's what I did.

 

The engine is on an engine stand. it wont be to difficult. i guess I will recheck the dots to make sure they are lined up. I just want to make sure I dont cause dammage. Non of you guys think by spinning it by hand I could of done dammage already right?

 

Take it from me, you better make sure those dots are lined up correctly, I screwed up my whole valve train because my dots were off, not a cheap fix at all. Mine did what yours is doing the first time, they are off. Tear it down and do it again. Or you will have wished you had, once you start her up.

 

the mounts arent even made to fit the car yet so a reteardown wont be to difficult, good thing i havent put on the whole pulley assembly yet!

 

I always heard how easy it was to slide the cam in but mine was a bitch to get in (last 1/3 of the way). Lining up the dots was rather easy, first try and they were lined up perfect. Made sure I rotated it over a couple times and they were still lined up so I threw the cover on.

 

I doubt you damaged anything by spinning the engine over by hand. Since you have the engine on a stand, you shouldn't have much trouble getting it right on. If you continue having the same problem after verifying the dots, let us know.

 

If worried about damage, do a leakdown test. Should be real easy with the engine out of the car.

 

I just finished a H/C install, and I don't see where it's so difficult to get the dot to dot lined up. If you're off a tooth, it's a long way off, and not hard at all to see. Maybe if you have the oil pump on, but...


Of course, I haven't started the engine yet, so, knock on wood....

 

Did you swap spring seats for the PRC duals? I have heard it's possible that the inner spring can bind if stock seats/ seals are used. It doesn't sit down far enough. The MS4 could be big enough to give you problems if that's the case.

 

I have not done one on an LSx based motor yet, but on the old school motors when you had multiple keyway timing sets there were 2 sets of marks for every setting, one would denote which keyway to use, the other similar mark would be the one you matched up with the mark on the cam gear (meaning if you had a timing set with straightup, +4, and -4 degrees, the crank gear would actually have 6 marks on it). Hell I built motors for years and had installed no fewer than 50 of these timing sets before, yet managed to screw mine up on my old truck. Guess that what happens when you stay up late working on stuff while having a few. I had ligned up the mark denoting the keyway instead of the other mark which made it several teeth off. Still ran but not very well, required a ton of timing and made like 290 lbs cranking compression.

 

no such thing on the LS1, two dots line them up. im going to re check it tommrow. I did replace the spring seats with the ones that were given plus the seals which were blue? instead of the black brown style ones. I guess its an updated design? i wanted to ask that also.

 

if it were PTV clearance issues wouldnt it be happening more frequently as each pistion would kiss whatever valve it's hitting in each cylinder? doesnt make sense that it would get hard to turn then go smooth when somewhere in the piston movement a valve is opening towards it.

I ask because I just installed a cam, and without the plugs in yet i can turn over the motor with a 12" 1/2 drive ratchet and the turning slows down a little before it speeds back up again.

 

I'll be able to tell ya in a day or so what color they are. I just ordered a set from TSP. I got a new set of springs from a friend but he used the seats on his heads....so I needed to get some. Might not even be your problem but I thought I'd throw it out there.

 

Your problem lies within the cam gear bolts or cam retainer plate. You have four bolts in the cam retainer plate that should be shorter then the rest. Then you have 3 slightly longer bolts that go into the cam itself. Id be willing to bet you have a longer bolt in their and its hitting the crank throw causing it to hang up. Its not a PR issue or dot to dot issue. I know because ive done this same thing when not keeping bolts in order or dropping the pan i had them in.

You can take this advice to the bank and cash that check