GenV LT heads on Gen3 LS block
Think underwater rocks in a rapid or empty pickup bed.
Last edited by LionPride; May 15, 2023 at 03:30 PM.
In regards to making the ports smaller, you could fill the floors with epoxy and then reshape the ports.
https://briantooleyracing.com/btr-lt...s-engines.html
Before that you needed a custom cam, not worth messing with.
The Best V8 Stories One Small Block at Time
https://briantooleyracing.com/btr-lt...s-engines.html
Before that you needed a custom cam, not worth messing with.
I think this is a very promising endeavor, especially if this person will be planning boost after he gets the mechanical side straightened out! I'm excited about a couple of these retrofits going on right now and I've been out of work for a while, starting a new gig today. As soon as I recover from being out of work in a couple of months, I'm gonna round up the stuff to do my own with a little different combo..
I think this is a very promising endeavor, especially if this person will be planning boost after he gets the mechanical side straightened out! I'm excited about a couple of these retrofits going on right now and I've been out of work for a while, starting a new gig today. As soon as I recover from being out of work in a couple of months, I'm gonna round up the stuff to do my own with a little different combo..
LS headers might fit, but it depends on the specific headers and your engine setup. Sometimes, slight modifications or adjustments are necessary for everything to work together.
Last edited by Davidsk; Sep 3, 2023 at 10:28 PM.
i was gonna ls swap my 4.3 boat and decided to a 5.3 lt as even stock heads and cam it will perform way better way more efficient then a carb and or port injection ls combo.
my 2017 zl1 with LME ported stock heads a very small cam on sbe with a ported stock blower made 970whp and now with a 2300 maggie on it as got it for 2k is making 1050. It’s the whole package and tons of lt swaps now happening taking advantage of the direct injection. Key is knowing how to tune the di correctly as I do.
as for this thread Richard did the swap and I do believe it was 100 hp gain with using the hybrid cam they had to grind and slight compression bump. So stock for stock seems like a really good gain on hp to do this head swap on an ls when comparing a 799 head to a 5.3 lt truck head. But as I said I’d keep the di and gain all the benefits of it.
i was gonna ls swap my 4.3 boat and decided to a 5.3 lt as even stock heads and cam it will perform way better way more efficient then a carb and or port injection ls combo.
my 2017 zl1 with LME ported stock heads a very small cam on sbe with a ported stock blower made 970whp and now with a 2300 maggie on it as got it for 2k is making 1050. It’s the whole package and tons of lt swaps now happening taking advantage of the direct injection. Key is knowing how to tune the di correctly as I do.
as for this thread Richard did the swap and I do believe it was 100 hp gain with using the hybrid cam they had to grind and slight compression bump. So stock for stock seems like a really good gain on hp to do this head swap on an ls when comparing a 799 head to a 5.3 lt truck head. But as I said I’d keep the di and gain all the benefits of it.
Can you actually show me proof that direct injection adds 60hp? I can almost guarantee that's not the case.
Why are you also comparing a "done right" LT build to a "common" LS build? Let's compare both that are "done right" and you'll see there really isn't much of a difference, with the edge going to the LS in that case.

Data for the graphs taken from relevant Richard Holdener videos to the best of my ability. It was the closest comparison
I could find. The shortbock for both is a 5.3 with flattops.
The LS is Summit Pro LS Stage 4 cam, Katech ported 706 heads, and truck manifold.
The Hybrid is the BTR swap cam, stock L83 head and L86 truck manifold converted to port injection.
Looks like pretty comparable. So long as you aren't looking to power a full featured street car, it looks like an option for a low investment small bore build.









