[TCSGTO]

Saw that too, anyone on here have any first person experience with using LS7 lifters in a Pontiac?

[PAUL K]

Originally Posted by TCSGTO

Saw that too, anyone on here have any first person experience with using LS7 lifters in a Pontiac?

Not using the LS7 lifter in a Pontiac but plenty with them in LS engines. They were the "go to" lifter for the LS engine until two years ago when they started having ticking issues. These were lifters purchased from GM Hopefully it's been corrected.

[70 bird]

Very interesting!

[Hammertime Mike]

subscribed

[Half-Inch Stud]

Thanks, very helpful for me.

The 0.442" lobe on me cam creeps me out.. I probably need to trade roller cams, for a smaller Street Roller.

[Formula8]

I had a 28,000 mile C6 Z06 and it ate a LS7 lifter in the first week I owned it. After doing a lot of LS homework, I concluded no GM LS lifters are long term reliable in a performance application. I am sure some use stock truck lifters with in their 1000hp LS builds but you see many with issues as well. I ended up ordering a set of Johnson's from Paul K (Fair price and hand delivery!). The car was quiet when I sold it.

That said, our retrofit lifters have issues as well. Looking at the video @ 2:00 mins, it appears the lower part of the band is lower than the Pontiac lifter. I wonder if that is going to be a problem?

[68WarDog]

I have seen on another Pontiac site where guys are replacing their comp hydraulic roller lifters with ones from the LS7. There's also a YouTube video crediting Jim Lehart with this modification . Apparently the lifters are more cost effective, lighter than other Pontiac retrofit brands, and made in the USA
Anyone here trying them, and where there any issues?

[Mr_GTO]

I think we're going to have 15 new threads about this before tomorrow. Check 3 threads down.

[68WarDog]

Maybe the moderator can delete my thread. Thanks

[i82much]

How is Jim doing? We had our political differences but at the end of the day I believe Jim Lehart is a good man. I kind of miss having him around!

[JC455]

Hi all!
I just finished my latest video- Like the title says, it’s about retrofitting GM roller lifters into a Pontiac V8!
Check it out- see what you think.
If you like it, please give it a Thumbs Up... and subscribe!

https://youtu.be/50I58n4vD8U

[P@blo]

Great video JC thanks for taking the time to post. I posted a link to my thread about the better quality snap-rings you mentioned for reference. Hopefully you plan to do a video about the whole process.

http://forums.maxperformanceinc.com/...47#post2602747

Also, the original youtube video stated the comp XR88HR has the correct base circle and have many guys running them with the 1.65:1 rockers. Other larger cams may require additional dog bone modifications. The Comp Cams instructions state:

"Final Check Spin the engine over by hand at the crankshaft with a wrench and watch closely to movement of the lifters. As the lifters move up and down, the lifter guides should remain perfectly flat on the tops of the lifter bores. They should not be moved at all. If they do, the camshaft does not have the correct base circle size to be used with these retro-fit lifters in non-hydraulic roller cam engines. Stop here and replace the camshaft with the proper one before proceeding. Running the engine with this condition will surely result in major engine damage."

[JC455]

Thanks P@blo! I’ve been gathering info for the proper dimensions of the snap rings— that sure helps!
Also, glad you liked the video!

[JC455]

I was curious about the “remaining flat” part, so I did a little checking.
The Ford Windsor small block has some large, beefy lifter bosses that are flat on top.
The retainer sits on this lifter boss pad and is held by the spider.
Here’s a video of modding an aftermarket Ford block due to retainer issues:
https://youtu.be/OBsWxi54XIY

Since we are retrofitting stuff that was never intended for our engines, we just have to do our best not to over-stress the parts.
I think we’ll be okay ��

[JLMounce]

Great vid! Definitely helps illustrate some of the pitfalls here.

So the only thing that could possibly still be an issue is the height of the non-machined section of the lifter. It appears to be coming out of the lifter bore high enough to push on the dog bone. I believe that is why the other member here pointed out that he's notching the dog bones, to avoid that happening.

That said, considering the construction of the dog bone and have a ball and socket connection to the spider, I'm almost wondering if it's meant to pivot?

[Singleton]

Nice video. I guess I have the same question as JLMounce above about the dog bone and the lifter flats.
Also, at the 6:33 mark of the video I believe you might have misspoke about the base circle being larger for more cam lift. Smaller base circle would be more lift if lobe noses are the same height, right?

[JC455]

Originally Posted by JLMounce

Great vid! Definitely helps illustrate some of the pitfalls here.

So the only thing that could possibly still be an issue is the height of the non-machined section of the lifter. It appears to be coming out of the lifter bore high enough to push on the dog bone. I believe that is why the other member here pointed out that he's notching the dog bones, to avoid that happening.

That said, considering the construction of the dog bone and have a ball and socket connection to the spider, I'm almost wondering if it's meant to pivot?

I was thinking about a pivot too.
I started pondering having the dog bones ‘floating’ on the ends of a retainer(spider)- that way, they are high enough to hold the lifters in line, but also held in place by a rigid retainer/spider vs. the thin sheet metal one...
maybe that’s what the guy on FB is making?

[shermanator2]

Thanks JC455 for the great video and thanks for listing me in the credits. I am very happy too that you pointed out with the straight edge and feeler gauge that the noses of various cams are all at the same height, although it seems that not everyone understands this concept yet.

I think that, as you have eluded to in the thread, the dog bones are our next interesting challenge here. Since with a properly designed cam, the fully round part of the lifter extends out of the lifter bore, the off the shelf dog bones are going to be lifted, which is not acceptable.

There seems two (at least) two different designs of dog bones out there. Even the pictures on Comp Cams web site do not seem to match what they are shipping. There are the ones with the tapered bottom which look like they are made to rock, which does not seem like a good idea, and the fully flat one that seem to be what Comp is shipping.

69HotBird had an interesting solution. With the fully flat dog bones, he milled the bottom with a carbide end mill to clear the fully round part of the lifter. The only thing that I did not like about this was that the flat part of the dog bone that was left seems pretty thin.

I had another thought. As long as carbide end mills are in play, can we mill the flats on the lifters longer, so that the fully round part never comes out of the lifter bore? Has anyone ever tried to mill a lifter? Then the off the shelf fully flat dog bones should work.

I am thinking that the ideal solution might be double thick dog bones that are relieved like the 69HotBird design. That would be a custom part though. Maybe not out of the realm of possibilities.

[JC455]

Originally Posted by shermanator2

Thanks JC455 for the great video and thanks for listing me in the credits. I am very happy too that you pointed out with the straight edge and feeler gauge that the noses of various cams are all at the same height, although it seems that not everyone understands this concept yet...

My pleasure! Since I’m NOT an expert in any of this, just a hobbiest, I try to take in other people’s thoughts and ideas, then apply them to my ideas/concepts.
I was curious about the relationship of the cam lobes vs the cam journal height, and was measuring gaps for my video...
Then I read your’s and others’ posts and knew I was correct in my thinking!
I’ve learned SO MUCH from people on this site- it’s amazing the amount of knowledge that’s floating around here, if one only asks.
Mr. P-body(Jim Lehart) got in touch with me, and has been very encouraging about this whole project— he seems like a really good guy!
I’m awaiting Randy Repp’s retainer/spider to evaluate whether the Ford/Comp piece or his will be more ideal for a no/low maintenance hydraulic roller setup.

[P@blo]

https://www.summitracing.com/parts/cca-31-1000

Click the "instructions" link. Not sure what to say as I was just relaying manufacturer's installation instructions. To me this did not make sense from what I read other guys posting.

Dog bones do not move if they do comp says wrong cam base circle is all I know thus far but could be on the wrong track.