Shawn MacAnanny

iTrader: (12)

I'm a huge fan of the LS1 engines and was thinking about dropping a 5.3L in my dune buggy which has not even been built yet because i want to decide on an engine and transmission to work around. Well i came across the LS4 and think that in conjunction with an automatic transmission would be perfect for a dune buggy! I would fabricate the frame so it sat on the rear end of course and i would get the spindles/hubs from an impala or monte car that way they would mate to the axles and give me a good start for a braking and suspension system.

The setup i am looking at is from a 2007 Impala SS 5.3L auto.

Anyway heres a few questions i have about the LS4. Does it have a 24x or 58x relector wheel? I'm considering running it carbureted like my LS1 unless there is a larger after market for the LS4.

My next question is i have read they have fuel management of some sort. This is not like the variable valve train setup on some LS3s right?

What sort of camshaft compatability do i have? What parts are interchangeable with an LS1?

I know the crank snout is shorter or something so it couldnt ever be mounted to a rear drive transmission could it?

Are the transmission electronically shifted? If so is there a valve body that will allow for manual shifts?

The heads on this engine are 243s correct? So they use ls1 style rocker arms and lifters then?

TiredGXP

iTrader: (2)

the earlier ones, 2005 for sure, maybe 2006 ,used the E40 ECM and a 24x reluctor wheel, when GM shifted to the E38 and E67 ECMs, a 58x reluctor wheel was used.

Active fuel management (AFM, or formerly known as displacement on demand, DOD) shuts off four cylinders under low load conditions in third or fourth gear. Oil pressure disengages 8 lifters in sequence and the fuel injectors for those cylinders are shut off. Completely different than variable valve timing.

You'd probably want to get rid of the AFM/DOD for you application. Overall not too difficult, a minor tuning change, replace some lifters, and maybe switch out the LS4 valley cover for the LS2 version.

If you're prepared to give up DOD/AFM then any LSx cam will work, just have to change out the DOD lifters.

The issue is that the LS4 has the bolt pattern for the FWD V6 bellhousings, you'd need an adapter to run a longitudinal transmission

Electronically shifted, the GXP comes with "tapshift" or manumatic mode.

Yes, there may be some valve stem height differences, not sure.

Shawn MacAnanny

iTrader: (12)

Ok im going to buy an MSD 6012 box, install my victor JR carb intake and carb from my LS1 and make it run carbureted. I think it will work! What do you think? The cam sensor should be the same one as an ls2 right? The firing order should be the same right? If i have the same cam sensor and same crank sensor i can get the coils to fire. I have an extra set of ls1 coils if for some reason the ls4 coil packs are different. Dumping fuel in with a carb will give me and easy fuel system, no wiring or computer head aches. I can swap out the lifters and make it non DOD. This to me WILL work right? I'm super excited! Haha I've been non-stop reading since i posted this.

I have also read the transmission bolt pattern may be the same as a 3800 camaro which i could put a t5 behind right? I know there is an issue with getting a starter on the small flywheel. I have an extra LS1 flexplate im gonna see what i can fab up just for future reference should i want to put an LS4 in my friends s10.

Shawn MacAnanny

iTrader: (12)

So how can i get the transmission to shift without a pcm? Can i install a manual valve body? Can i creat my own sort of stand alone shifting method for the transmission. I can imagine its too advanced. I know that the 4l60e valve body can be swapped to run manual only. Maybe i can find a way to make the electronic shifting work

Shawn MacAnanny

iTrader: (12)

Also does the auto trans have fittings to run a transmission cooler?

Can i run a lower final gear ratio in the transaxle i.e 4.10 instead of 2.93. I want to run big tires like 40" or so and im sure it was only designed to run 26" or so.

How strong are the axles? I'm thinking of lengthening them so i could drop the wheels further and make the chasis wide.

TiredGXP

iTrader: (2)

I think the LS2 cam sensor is mounted in a different orientation than the LS4, I seem to recall a guy who was putting a LS4 into a Fiero swapped in the LS2 timing cover and had to make a few mods. At any rate same firing order as LS1, 2, and 6 (1-8-7-2-6-5-4-3.)

Yes, same bolt pattern as the 3.8 Buick 90* V6.

The other issue is that the LS4 doesn't have a starter mount cast into the block. The starter mounts on the transmission bellhousing, so you'd have a bit more fabrication to do.

Why not go with the 5.3 iron block from a truck? I know it's 80 or so pounds heavier, but doesn't have the DOD and is already configured for RWD.

Shawn MacAnanny

iTrader: (12)

Well i want to run a FWD engine the buggy. I can mount the engine up higher. Make the axels a little longer and mount the spindle down lower and out further to add ground clearence and stability whill keeping the oil pan up higher and having IRS. See with a solid rear, and front engine setup i will have poor clearence due to the rear end pumpkin, the driveshaft, and not to mention even more poor traction. I dont think this buggy will weigh more than 1000-1200lbs.

I was exploring the idea of RWD for a friends S10. I like the idea of the LS4s haveing the 243 heads on them already and being all aluminum. It doesnt affect my swap at all though.