Ls swap

[Kemper1976]

I want to make 400 at the wheel before turboing It. Any suggestions. And I was told I could use 1.8 rockers to help me with power.

You can use the 1.8 rockers and the lift will change to .593/588. I personally haven’t used 1.8 rockers so I can’t say the gains are worth it or not. Might be a little tougher on the rocker arms though. Hotrod has done a lot of Dino tests with Ls setups. You could probably find great info there. LS1 tech will also have a ton of info as well.

You have a very good turbo setup as is. Most or your gains will come from tuning and heads.

If done correctly, heads are going to be an area you should look into. The pocket port work done underneath the valves is going to give you the most beneficial gains.

You can do intake and exhaust port work but I recommend just doing a mild casting cleanup or “machined finish” on the intake side and smooth (polished) Exhaust side.

There are really no power guarantees on any motor. Identical motors can be 30hp apart sometimes.

 

[Turbolq4]

Won't be able to make that power with a factory cam. Trying to make Dyno horsepower NA is counterproductive if you plan to boost it later. Turbos like milder cams than max effort NA builds/dyno queens. Which trans are you running? Borderline unobtanium numbers with a power robbing slushbox.

 

[Big girth]

What to do to get 400 to the wheel with a carbed setup.

 

[Kemper1976]

You’d really need to build a n/a specific motor in order to make even 350rwhp with the 5.3 unless you spent a ton of money on custom ground cam, heads, Intake etc.... if your budget allows for a larger ci motor, I would do that.

As turbolq4 said, you’re basically not going to find the power you’re you’re looking for n/a when using parts that are more beneficial on a boosted motor.

The B8 LSX 376 which is a boost specific motor rated at 476 crank hp using the LS3 cam will only lay down a little over 400rwhp.

Here’s a good test article below. This test was done showing crank hp using factory cams on an efi 5.3. At the bottom it’ll show the crank hp for 3 aftermarket cams.

https://www.google.com/amp/s/www.hotrod.com/articles/ls-cam-test-comparison/amp/

 

[motorheadmike]

What to do to get 400 to the wheel with a carbed setup.

Nitrous... or cam it and rev the sh*t out of it... or both.

This is about 8 years old, but the principle remains valid:

http://www.superchevy.com/how-to/project-cars/sucp-1111-5-3l-ls-small-block-build/

http://www.superchevy.com/how-to/project-cars/sucp-1112-5-3l-ls-small-block-build-part2/

http://www.superchevy.com/how-to/project-cars/sucp-1201-5-3l-ls-small-block-build-part-3/

http://www.superchevy.com/how-to/project-cars/sucp-1203-5-3l-ls-small-block-build-part-4/

http://www.superchevy.com/how-to/sucp-1206-5-3l-ls-small-block-build-part-7/

Long story short: you are going to live a life of perpetual disappointment if you don't do a lot of planning, and manage your expectations throughout the process. You will not just slap some shittily mismatched parts together and put a half-assed tune into it and become parking lot kingshit. This needs your whole *ss and a lot of work.

 

[Turbolq4]

My turbo 5.3 made 463 wheel. Dyno estimated crankshaft horsepower at 614 through a 4l80e and a Ford 8.8. be ready for some disappointment if you were looking at anything but a manual trans and a tiny rearend.

 

[Big girth]

Do you have to use a blow thru carburetor with turbos if. Carbed ( or I can use my regular Holley 750cfm).

 

[Big girth]

And what’s the biggest transmission I can use without cutting the driveshaft and getting a cross member. I have a th400

 

[Big girth]

My turbo 5.3 made 463 wheel. Dyno estimated crankshaft horsepower at 614 through a 4l80e and a Ford 8.8. be ready for some disappointment if you were looking at anything but a manual trans and a tiny rearend.

What size turbo you running.

 

[Kemper1976]

Do you have to use a blow thru carburetor with turbos if. Carbed ( or I can use my regular Holley 750cfm).

Do you have to use a blow thru carburetor with turbos if. Carbed ( or I can use my regular Holley 750cfm).

You will have to use a blow thru carb. Standard carb won't work under pressure. Check Out CSU carburetors they're in the article below. I had one on a procarged BBC setup in my 70 chevelle. Worked very well.

https://www.hotrod.com/articles/build-blow-carb-less-50/