LS7 lifters in an LT1

[Jazz]

For anyone that isn't aware, you can run LS7 roller lifters in an LT1. They are a drop in for the block but are .1 taller so you will need shorter push rods. They are a designed for high revs and for about $105 a set they are a bargain too. GM Part number 12499225 get's you 16 of these bad boys. I highly recommend them.

With stock heads and block, using Fel-Pro gaskets, my pushrod length came to 7.000 (stock is 7.200). Its also really important to check this because my stock setup which I didn't measure appears to have been .085 over in the pushrod length. Replacement pushrods are TrickFlow and at less than $100 again these are a real bargain.

With 1.6 rockers and heavier springs my stock pushrods didn't last more than 2000 miles. Being longer than necessary didn't help.

Now the real question. Will the motor make any more power with hardened 1 piece pushrods and LS7 roller lifters. My factory setup had 180,000 miles on it and I believe the pushrods were bending. I also damaged a roller rocker (Proform) which I will also be replacing. They are available for $18.99 each from Summit.

So, life is good again and I've go some work today. Racing always finds the weak link it seems. Glad it wasn't something really big and expensive that broke this time!

Merry Christmas....

Jazz

[Profit Of Doom]

decided to go with a new rocker too? CYA reasons or did you find a defect after the meet?

[Jazz]

I decided to buy a new rocker because they are available as individual pieces from Summit without a lot of hassle. The cost isn't bad but I didn't want to buy a whole new set just to get one. It's on backorder though and won't be here until after Christmas, so for now I'm going to run the old one and replace it as soon as the new one comes in.

[The_rabbit1]

Now the real question. Will the motor make any more power with hardened 1 piece pushrods and LS7 roller lifters.

No pushrods won't make power nor will lifters. It's all a piece of mind thing, i dont skimp out much on my parts, especially valvetrain.

I'm running one piece forged rods, full race lifters and i'm saving up for the comps gold line rockers, i've seen too many f-bodies F.O.R.D cuz of skimping on parts.

If your running stronger springs i'd run the forged one piece rods, and guide plates, and the LS7 lifters wouldn't be bad, i'd check on pricing versus a set of disc plated aftermarkets though.

that's just me, then again i haven't had to tow my f-body home after a meet.

[Jazz]

I don't think I'm running enough RPM's to really need guide plates. Basically the stock rods just aren't good enough for my setup. Either way I'd agree that pushrods aren't something to go cheap on. Heck, the Trickflow's were only $85.00.

By design lifters themselves shouldn't make a horsepower different, but with proper length pushrods that are hardened moly the deflection in the pushrods should be less. I wonder if they were bending slightly which would result in reduced lift on the cam. Same for the lifters. The question is what difference would wear (180,000 miles) have on their performance. I might find it made no difference at all and I just wasted $100 on lifters.

BTW - For an LT1 the only lifter that makes real sense is the LS7. It's half the price of any comparable aftermarket part with performance that's on par with most of the aftermarket pieces...

[Profit Of Doom]

I would say you should see some difference.. because as we all know worn out parts are never good horsepower makers

[Jazz]

Well - If you listen to my friend Eric (NRFD on this site) - a motor makes the most power just before it blows up :)

[grn95t/a]

I don't think I'm running enough RPM's to really need guide plates. Basically the stock rods just aren't good enough for my setup. Either way I'd agree that pushrods aren't something to go cheap on. Heck, the Trickflow's were only $85.00.

By design lifters themselves shouldn't make a horsepower different, but with proper length pushrods that are hardened moly the deflection in the pushrods should be less. I wonder if they were bending slightly which would result in reduced lift on the cam. Same for the lifters. The question is what difference would wear (180,000 miles) have on their performance. I might find it made no difference at all and I just wasted $100 on lifters.

BTW - For an LT1 the only lifter that makes real sense is the LS7. It's half the price of any comparable aftermarket part with performance that's on par with most of the aftermarket pieces...



correct me if im wrong but i don't belive that you could use a guide plate with the narrow body self aligning proform rocker arms. there just like the stock rockers, they have alingment disks on the front small roller to keep them straight on the valve head. you would have to change to a non self aligning rocker arm, like the comp pro magnum rollers that i'm using. i have always heard you can use one or the other but not both together.

[Jazz]

New LS7 roller lifters are in along with 7.00" Trick Flow hardened moly pushrods. Adjusting the valves and putting the intake back on tonight. All is well in the world again...

[The_rabbit1]

correct me if im wrong but i don't belive that you could use a guide plate with the narrow body self aligning proform rocker arms. there just like the stock rockers, they have alingment disks on the front small roller to keep them straight on the valve head. you would have to change to a non self aligning rocker arm, like the comp pro magnum rollers that i'm using. i have always heard you can use one or the other but not both together.

forgot the rockers were self aligning, you are correct.