I knew your overall goal, I was Just hoping to see it finished.

Lots of people ask about bumping the compression by using a 4.8 piston's in a 5.3

I was also working on a similar combo but the Budget and time frame went out the window. I finally got all my parts back, I just haven't had time to work on it.

 

Ah yea I've had the same things slowing me down. But it won't be Much longer. Ive found it interesting how valuable time has become lately. All these projects plus 3 young kids... time flies!

 

I thank y'all for the work that's been put into this thread. I wasn't aware of the benefits of the 4.8L piston swap into a 5.3L until now.

Would anything change or have to be changed to keep the compression bump if using #799 heads?

 

4.8 piston 5.3 those heads, would be a nice set up. You'll have plenty of PTV clearance assuming your not running a crazy cam.... even then you'd probably clear! lol

But you'd have a nice set up with great flowing heads. Those pistons would help the compression with the larger chambered 799 heads of 64cc vs the stock 5.3 heads of 61cc.

 

What would the compression be if I put the 4.8L pistons in my 5.3L & used stock/non-milled #799 heads with the factory 5.3L heads gasket?

 

Quick update for everyone. I've finish porting the 862 cast heads for this 5.3 with the 4.8 flat top pistons. I dropped them off at the machine shop this week to get a vavle job. The'll be cutting out the intake seat from the 1.89" to fit used LS1 2" vavles. Exhaust vavles are already the same as LS1.

I hope to have this motor swapped into my '87 Chevy truck with a 4l80e within two months. I'm going through my parts list this weekend to make sure that I have everything.

Getting close! I may do a video of it running on the engine stand before install.

 

I got 10.21:1 with those unmilled 799 64cc heads on a 5.3 with 4.8 flat top pistons.

 

You didn't post the update video over here like you thread on the tech side... https://ls1tech.com/forums/generatio...w-video-2.html

How does the parts list look???

I picked up another truck so I haven't gotten back to any of my engine builds. I have been focusing on getting all the little things fixed so I can use if for a my new DD and sale my current DD. Also need to get rid of some of my Extra parts to make some room...

 

That sounds like a nice gain! What head gasket would I use?

 

I think i did post it here. Check post #58. Is that the video that you're talking about? For some reason on this site it doesnt show the player like it does on the LS1 site. But good point showing that Im trying to maintian two of the same thread on two different sites. lol thanks!

I didnt get a chance to go through the parts list yet. I really hope to this weekend. But in my head, I think that I have everything except fuel hose. I need to installe the higher flowing fuel pumps before the swap still.

I've been slammed lately and it seems impossible to make good progress on these projects. Im considering taking vacation time just to get some done.

LS Fest is coming up quick! lol