Ok so i came home the other day with a free 98 model Vette LS1.. With the hopes of slapping it into my 07 GMC.. I know that the crank and cam sensors have different reluctor teeth, the front cover from my stock 4.8 should swap over and use the ls2 cam gear for the 4x cam sensor, the crank is going to be changed to have the 58 tooth reluctor.. Other than that i was wondering what cam and head combo to use.. Obviously if i could use the stock LS1 heads that would be optimal (money reasons) maybe a slight port job? the intake on the 4.8s in these trucks have the cathedral ports right? so it should bolt right up to the 5.7??? or do the 4.8s come with the square port heads like the l92s? Will my stock fuel pump keep up with this combo? I want to run the truck manifold for the torque addition.. Thought about throwing a little more compression to it too.. like a 10.8:1 with a TR220 cam 114 LSA.. I tow with this truck so i am looking for torque output.. I DD it too so drivability is an issue and the thing has to have at least a noticeable idle so that the kids in town get scared when they hear it running.. Found a company that ports the plastic manifolds and TBs anyone had this done??

I know that this is alot to ask in one thread, i am kind of building the all in one truck.. I want it to do everything, tow my 79 trans am if i need it to (with a heavy *** 455 in it) get more than 14 mpg average (with foot out of throttle), and scare the wife when i step on the gas.. I drive the hell out of this truck and to be honest unless someone hits me and it cant be fixed this is going to be my last truck.. Love this thing just want some lopey idle action and some more power..

I live in Columbus In and wait4meperformance will tune it for me, he claims that he can tune anything i could do to the truck..



4.8 4l65, no power locks or windows, G80 rear axle with 3.23 gears, wanting to switch to 3.73 or maybe lower???.. (would love to swap to a 5 or 6 speed manual)

Help me get my head on straight and figure out what to gather befor i do this swap.. I cant be without my truck for more than a week at a time..

Thanks

Whew!!!

 

It should work but you have to mount the Gen IV Knock sensors on the LS1 block on the side. Just use one of the bolt holes close to were the stock 4.8 ones were should work.
Also just use the stock 4.8l valley cover as well. The intake ports are the old style. So the intake will work as well.

Should be easy and done pretty cheaply it you find used parts.

I would stick with the auto and swap to at least 4:10's if you tow alot and are 4x4! Then swap to a NV4500 later.

 

Im not 4wd.. I was thinking about doing the T56 and 4.56 after having read the thread on the M6 swap.. Really like manual transmissions.. IDK.. it is glad to hear that the LS should theoretically be an easy swap..

Was thinking of finding an SSR T56 and using that for the M6 swap.. I want to do all of this at once so that i dont have to be without my truck for too long..

thanks

If anyone has pics of a NNBS with a 6 speed done i would really like to see them..

 

If by the 4wd you were refering to the 4x that is the newer cam position sensor, it has 4 spaces for a 4x cam position, gives better feedback on positon much like the increase in tooth count on the crank sensor from 24 to 58 gives a better feedback on crank position.. At least i think that is where you got the 4x4 from??? Thanks for the feedback..

 

98 LS1's suck
the rod bolts and weaker, the heads are horrible with the perimeter bolt vavle covers
and some of the blocks have pores that leak oil through the block its self(casting defect)
if I were you I would pass

 

if anything . sell the motor . invest in a front mount turbo kit for that lil 4.8. run about 10 psi .

 

I would do a 6.2L swap

 

I would like to say that this block says 98 but was actually outfitted with center bolt valve covers, production was 7 of 98 i think (dont have it in front of me) I would love to turbo the truck but i feel that would make it even more likely that i'd keep my lead weighted foot in it all the time. I cant sell it due to its origin (cant tell ya or i would have to kill you, and no it isnt stolen) I would love to get a 6.2 and change cam and timing set to delete the VVT, as long as one of you guys will foot the 5k for one.. As i said this engine was free and you work with what you have.. I feel that this engine will be a big improvement over the stock 4.8, i will have to tear it apart to change the crank reluctor, rather to have someone change the crank reluctor.. so i had planned to fill it with ARP fasteners.. If i really wanted to blow money i would opt for a 383 stroker kit and make it a 6.3.. May go that route yet anyway.. How terrible are the factory 4.8 heads? anyone have any specs on them? Just curious.. Not trying to get 600HP from this thing, want torque and something that will last a long time.. Good components.. i dont want to build this thing and then be doing this

Thanks for the input, keep it coming..

 

I was asking if the truck was four wheel drive.

But since it's not and your thinking a T56 I would get 4:56 gears. Since the trans has a nice OD.

I believe the factory 4.8 heads now are 243's like the 5.3's. What casting number does the heads have on the 4.8L now?

If there not just get a set of 243's and a LS6 cam. That would be pretty cheap, make nice power.


Your going to spend alot on the T56 and swapping it in, so I would keep the motor cheap as you can. I'll still make plenty of power.

Plus you can always swap to a L92 etc later. Since it will bolt right in!

 

Been doing alot of reading and for the sake of not changing too much at once im going to do a few upgrades to the 4l60 and keep it for now.. I really want to do some gears to help with the low end grunt.. Any suggestions for a good towing/street fun gear, not drag racing or anything and still drive the truck on long trips every so often..