4th Gen LT4 Swap Help

[GypsySteve480]

Hello everybody.
i have a 98 camaro Z/28 that is set up for drag racing 9" cage th-400 etc.
long story short it had a 408 nitrous engine builder did not measure correctly piston was hitting head motor came out was about to rebuild when i came across a great deal on a stock
2019 LT4 with 8L90 end up buying it. this is going to be a max effort LT4 im not sure of the blower limit or fuel limit im debating about a bigger blower before the swap. i will not be using 8L90 using th400 due to dedicated race car. i will be using a Holley System instead of stock harness

we are about to start the swap here in a few weeks and im trying to put together a list of what i need so i can start buying parts now.
i was hoping to get some help or tips from someone who knows or if there is any problems im going to run into.

ive just started doing research these last few days and have not found much about this swap.

also as far as mod list thinking
Cam kit meth tb headers converter arp bolts i was told air to water system would be big gains.

i would like to hear the guys with LT experience with mod list as im coming from ls VERY new to lt world goal is high 8s low 9s
.
Thanks for reading and your help.

[harner]

Hey there. Unfortunately, most of the resources on this forum focus on the LTX platform from 1992-1997. However, some of us have a little 15+ LT1/LT4 experience.

My recommendation is if it's a max effort build, look into the Kong 2650 blower. https://kongperformance.com/collections/kong-tvs-2650/products/kong-performance-lt4-tvs2650

BP Automotive makes some great standalone harnesses, but it sounds like you are going the Holley route. Have you given a thought to the fuel system yet? My brain is a bit hazy from when I owned my 18 ZL1, but I recall there being a low pressure side and high pressure side. You'll most definitely want to upgrade to hit big numbers as fuel seems to be the a big limiter on this platform (vs LS cars where you just throw a big pump(s) and injector at it and call it a day). Check this out: https://www.vaporworx.com/resources/pwg/lt1-lt4-engine-fueling-requirements/

I'd talk to Kong about a matching/common TB that pairs with his blower, either the 2650 or even a ported blower. There are a few out there that are common upgrades. I'm not up to snuff as to swap headers in a 4th gen, but I'm sure something exists. It would be a shame to go all out and be forced to run manifolds.

Motor mounts are a concern, but I think I saw swap plates on the ict billet website.

For cooling, I'd try to mimic a stock heat exchanger setup but essentially with an aftermarket hx. Like Afco. Or no hx and run an Interchiller setup, but not sure if that's a great idea on a track car since they are prone to condensation.

Meth, E85, converter, heads, cam, ported blower or 2650, fuel system, that should be at or near the 1000whp mark on the stock bottom end. Maybe more depending on the blower and how much boost you'll be pushing.

[harner]

Also, what is your cowl situation? Not sure if an LT4 hat would clear the cowl let alone a 2650.

[GypsySteve480]

Thank you very much for the reply that was of much help. you are confirming that kong is the way to go when it comes to blowers also thanks for the fuel links i was worried about changing a fuel system im going to look into the high and low side.





Hey there. Unfortunately, most of the resources on this forum focus on the LTX platform from 1992-1997. However, some of us have a little 15+ LT1/LT4 experience.

My recommendation is if it's a max effort build, look into the Kong 2650 blower. https://kongperformance.com/collections/kong-tvs-2650/products/kong-performance-lt4-tvs2650

BP Automotive makes some great standalone harnesses, but it sounds like you are going the Holley route. Have you given a thought to the fuel system yet? My brain is a bit hazy from when I owned my 18 ZL1, but I recall there being a low pressure side and high pressure side. You'll most definitely want to upgrade to hit big numbers as fuel seems to be the a big limiter on this platform (vs LS cars where you just throw a big pump(s) and injector at it and call it a day). Check this out: https://www.vaporworx.com/resources/pwg/lt1-lt4-engine-fueling-requirements/

I'd talk to Kong about a matching/common TB that pairs with his blower, either the 2650 or even a ported blower. There are a few out there that are common upgrades. I'm not up to snuff as to swap headers in a 4th gen, but I'm sure something exists. It would be a shame to go all out and be forced to run manifolds.

Motor mounts are a concern, but I think I saw swap plates on the ict billet website.

For cooling, I'd try to mimic a stock heat exchanger setup but essentially with an aftermarket hx. Like Afco. Or no hx and run an Interchiller setup, but not sure if that's a great idea on a track car since they are prone to condensation.

Meth, E85, converter, heads, cam, ported blower or 2650, fuel system, that should be at or near the 1000whp mark on the stock bottom end. Maybe more depending on the blower and how much boost you'll be pushing.

[GypsySteve480]

cowl is completely cut out wipers motor is all cut out

[SSlowBoat]

i would change it over to full port injection instead of using the DI since its a drag car. There are intake manifold lowers designed for it. the limiting factor on the lt4 seems to be the di fuel system, even with a cam swap that has the overdriven lobe for the DI fuel pump.