2QUIK6

There has to be a point where a stronger than stock timing setup is required. Its all going to come down to valve spring pressures for higher lift cams.
There's tons of responses indicating they used a stocker, but what is missing is their valve lift and spring pressures.

What is the limit for the stocker timing set???
With Comp 977 sprigs which have over 400# seat pressure, I'd think a stocker would be pushed past its limits there with .600+ lift.

Silvershark

I just purchased a motor setup from a friend who spun a rod bearing initially and then caused him to spin a main bearing and the motor seized. The timing chain didn't break. I think the stock piece is very good quality and can handle some decent abuse. I am going to see if I can get the block cleaned up and see if it is reusable.

Anyhow, I wouldnt think twice about using the stock timing chain.

I have two spares sitting in my garage.

Z-RATED94

You have a good point. But for most of us the stocker seems to be a pretty good bet. I would replace the gears and chain though.

turnin20s

+1 for me too. If you are still using close to stock valve springs and a smaller cam the stock pieces will probably do just fine, but once you get into the bigger cams and higher spring rates its probably a safe bet to just get a double roller or a stronger setup. You could continue to use the stock pieces and some people may not have any problems, but the chains do stretch alot after some time with a stock setup, so imagine what it would look like after some time on a modified valvetrain setup.

2QUIK6

Yeah, from my ealier post, just what are those stocker limits for lift and spring pressures?? anyone know?

I'll be doing a cam swap again soon and I'm just going to reserve judgement on what I'll use until I get the ED one out to inspect it.
Funny thing is the couple of failures that I saw pics of it was the cam gear wp teeth that were worn and not the wp gear itself....the ED set is supposed to be hardened, hence the reason to use the supplied wp gear...but the wear on the cam gear reflects just the opposite....
Also, as pointed out in one of the previously mentioned threads... Be certain that the wp you use that the shaft turns freely!! Several gear failures can be contributed to the Bosch replacement wps not having correct specs and the shaft could not be turned by hand..there was a recall from Bosch for this issue, but I'm sure most of those pumps still made it or are still on the shelves.
Its common to replace the wp while its off. I know 1 of the 2 I inspected at the auto store had a very tight shaft.

96capricemgr

The WP is an 11hp load at 6000rpms using an electric would take that load off the timing set which would serve to make this already good piece last longer.

Far as spring pressures and lifts well I can't go too indepth there but I will say I am running 918s setup to about 140 on the seat so it isn't like the ZZ3 cam I used to run with 110 on the seat. I am not running anywhere near the .600 lift that some guys are though.
Was setup to a degree for endurance I want to be able to put 10K a year on it for a couple years before I worry about springs

ABA383

When LPE originally built my motor they used the stock timing set...When I had the heads freshened by Eric Bradby and installed a cam from Joe O. we just replaced the chain with another new stocker on Joe's and LPE's suggestion...and I thought Joe told me that he was running a stock timing set on his 9 second set up...I'd say thats a fairly good endorsement...

--Alan

mdacton

he had that extreme duty gmpp timing set.......Joe ran a stocker forever tho, I think he went 10.20's on motor with a stocker. Many people ran them for a long time, before everyone started running the double rollers

neil350

Interesting topic, I have heard from a lot of people that the factory LT1 chain is a really good unit. Thats what I plan to use when I do a cam swap. Its always funny when you see these cars that run really well and you hear what parts are on them.

kline454

yeah im running a stock replacement, with my car no problems went 11.30 before i just did some head work and added more n2o, changed the 1st one out a 140k still looked good.

JoeliusZ28

Ill be running beehive springs when i do my cam swap and ill have a decent ammount of lift too (less than .6 though). I guess we shall see.