I have been wanting to do a LS motor swap into a KAPA platform for the past ten years. So I finally stated amassing the parts to make it happen.
• LQ4 out of a running (but not driving…CRASHED) 2001 Silverado.
• T56 trans plus collected parts like steel fork and solid keys ready for rebuild
• Ls6 intake
• Mounts harness radiator driveshaft e67 ecu
• Lots and lots and lots of mis parts to make it happen
• OH YEAH and the car its self.


I was on the phone TODAY with John from Texas Speed pricing out and getting ready to purchase a 408 kit for the thing as well as some heads so I can get to machining and hopefully finish everything up before summer. Unfortunately, this evening’s mail contained a final billed amount to insurance for surgery I had earlier this year (I’m good as new now and even better with some metal plates thrown in the mix) It ended up costing almost triple what I thought it was going to be. Even paying 20% of that value plus deductibles and all that shenanigans, I am completely hosed. Needless to say, my stroker planes are dead as of this evening.

I am not giving up on the goal of getting a v8 into that car but I will be dealing with the medial bills for a long time.

SOOOO I need a change of direction so I can get that motor in the sky. You only live once!

I am trading some old parts for 243 heads ported with oversize valves. I am planning on still snatching up a cam kit of some sort. I would like to throw the heads and cams in with the LQ4’s stock bottom end. Here comes the tricky part. I would have no issue just lumping everything onto the high mileage lq4 (180K+ miles) and having fun but I need a 58 tooth reluctor wheel. The reason for this is that the only way to keep the factory traction control, gauge clusters, and cruise control is to use an E67 ecu.

Seeing as I need to pull the crank out to press in a 58 tooth wheel should I do a cheap refresh while I am in there? Or just slap it back together. What can I do with this thing? Bearing and rings? What kind of cylinder prep would be expected if I went with new rings assuming the cylinder walls aren't completely out of whack?

It’s no stroker, but I am sure that LQ4 with the ported 243 heads and a fat cam could make some fun numbers and I’ll have a fun weekend warrior to boot. I am almost there, so please help me jump this last little hurtle.


Any input would be great!

 

Definitely do rings and bearings! Do you have a budget on heads?
What ever you do don't use LS7 lifters. 408s are strong motors if only the TOP END is well Matched. I have seen 450rwhp 408ci motors up to 575rwhp 408 motors.

Is this a street car or is you plan on putting it on the strip alot?

 

I have done what I can with the head as far as budget goes. port polished 243s. I no longer can chase around 1700-2000 head options.
The only budget I have left at this point is a last ha-rah for a good cam.

It will be a street car. Maybe some drag events every now and again.

I have one more point/thought to add.
I would hate to see the stock bottom end LQ4 with the 243s and a cam make mid low 300 hp rang. I am already there with the turboed four banger that's in there lol

 

Whelp apparently I am more fickle than I knew. Going along with the title of the post, my planes changed AGAIN. I went ahead I ordered the 408 rotating assembly... Along with a cam kit.

You really only do live once after all.

 

Awesome!! Do you still plan on using the 243 heads?

 

Yeah I am still going to use the 243s. Can't really dig up 2k for heads of any other caliber at the moment. It was suggested to me that the ls6 intake will be the weakest link at this point anyways and I should seriously look into an alternative.

 

Wait a little bit till the MSD for Cathedrals come out and there will
Probably be a lot of good deals on used FAST Intakes both 92s &
102s preferably. On a 408" Ideally you want at least a well ported 92
W/ a 90 MM TB. Well ported (Mamo) 92 worth at least 20 vs LS6!
102 as much as 30 on a 408 with heads and medium + sized cam!

 

Don't worry, 243 heads are plenty capable of 500whp unported. It just takes a good cam and intake selection.

 

I must admit those MSD intakes look really good! If the performance for those big guys are what they advertise I will probably be pick up one of those as well as the ls2 throttle body when the appropriate p/n is released. It is clear the ls6 intake needs to be dumped.

In the mean time parts are starting to trickle in here. I hope to have everything for the bottom end here and have the motor off to the shop by the end of next week!

 

Block is off to the machine shop for boring and all that fun stuff.

I do have a question about head gaskets.
Are there any difference between ls2 lq4 and LS3 head gaskets other than the bore diameter? ie coolant galleries and passages or dowel pin locations
I will be running an oem MLS gasket but I need to take into consideration the new 4.03 bore as well as the combustion chamber diameter of the 243 heads. I was thinking the head gaskets with the 4.08 bore would work fine but I am not sure if there will be misalignment issues with other features of the gasket if there were any differences in block architectures.

Any thoughts?

 

ttt

Any help would be great.

 

LS3 gaskets will work fine.

 

Great thanks!

Gaskets have been ordered.

 

Parts are piling up!




Thumpy cam









hand ported heads with + sized valves and double springs





This crap is everywhere!

 

You /\ go in there! \/

 

Intake is here finally!



Waiting on TB now.

 

I finally had time to assemble the motor


Pulled out the 2.0L


And get everything ready for install.


Now I just need to get the transmission together.