Alright guys, so im getting ready to build up my little 4.8 over the winter for my race jeep next year ( replacing a tired 327 SBC)

i dont want any of the "swap a 5.3 or a 6.0" crap in here, i have a good running 4.8 and it will be going into the jeep.

i would like to get 350-400HP out of this motor without spending 5000$

im pretty sure a cam/ heads and tuning alone will get me close, but im a complete idiot when it comes to cam selection, and every internet search yields cam opinions for street trucks, this jeep is offroad only, no emissions, no traffic just racing

Here is some background info:
4wd
4:10 axle gears
locked front and rear
probably run a 3000 stall
powering a turbo350( manual valve body and built up for the jeep)
241 or 208 transfer case
video of the type of racing we do :https://www.youtube.com/watch?v=7JoPlgHuQc4

id like to spin the 4.8 to 7-7500 rpms if possible

motor has 862 heads and a truck manifold at this point

need to know:
cam
heads
oiling modifications?

thanks

 

do you want to buy heads or get some factory heads worked or what?

are there any rule restrictions on what you can do?

 

Their are no class restrictions for motor, just wheelbase..

I can do either, this is my first adventure with an LS motor and what ive been told is the factory heads are not to bad..

I had too many carb issues last year and really want the throttle response and ease of EFI, So keeping the factory EFI and electronics, and staying NA are really my only BIG requirements

id like to be at or around 2000$ for the build if possible..

 

243s milled to 60cc with a 227/231 should get it done.

 

243s would be a ls6 head?

227/231 cam

spring upgrade would be needed obviously..

milling the heads to 60cc would give me What for a compression ratio?



anything else i should do to increase strength or reliability while im in the motor

also looking at prices im looking at 500$ for used 243 heads plus milling... would their be good enough gains to warant just buying aftermarket heads for 1200-1500$?

like these?http://www.summitracing.com/parts/tf...make/chevrolet

 

LS2 timing chain, trunion rocker upgrade, hardened pushrods, good valve springs and spinning that high I would do link bar lifters.

60cc will be roughly stock. I believe yours should be 59cc stock.

Those trick flows are $1100 each so no. SDPC makes a good 243 worked head milled to 60cc for $550 each.
https://sdparts.com/details/scoggin-...center/sd8926c

Just finished watching the video. I would go a little lower on the cam maybe more like 224/228 or 222/226.

 

whoops lol, it said headS where most others said HEAD so i assumed pair, alright so those heads you linked look nice. for the cam and RPM level, are the ls6 springs included going to do the job? or do i need to upgrade further?

looking at some data the 862 heads are 61.15CC stock, so 60cc would bump compression just a smidge.

was thinking of this kit for springs, this also has the trunnion bearing upgrade also, if im reading correctly...

http://www.summitracing.com/parts/sme-k-14300/overview/


so heads: 1100
springs: 300$

cam: 3-500$
http://www.summitracing.com/parts/cr...make/chevrolet
whats better about the LS2 timing chain?

And pushrods you say hardened.. chromoly?
http://www.summitracing.com/parts/tf...7200/overview/
like these, obviously in the correct size for my application

ill have to research the "link bar lifters"



also what about fueling this bad boy, besides tuning, will i need to upgrade injectors or anything?

sorry for all the questions but the LS setup is very new to me

current motor is just a 10:1 comp 327 with alum heads and a mild cam

 

Any hope for just milling and a quick polish on my existing heads?

 

LS6 springs won't be enough, I would give SDPC a call. They are a site sponsor and will hook you up. They can substitute as needed and build you out a well speced package for your needs.

A good working of your stock heads will work pretty well, but have its limitations for sure. You can give West coast cylinder heads if you want to use your current heads.

Ls2 chain is much stronger/beefier.

 

Ok thanks, what are your thoughts on the summit valve train kit, those springs and bearings up to the task?

I'm thinking I may just cam/ springs/bearings/ chain this season and look into heads next winter as my axles are really begging for an overhaul this winter too

Now to hook this bad boy up to my th350, I know I'll have to oval tq converter holes.. Is this going to make it weak?

And do I buy a converter for the th350 or for the 4.8 lol

I'll make some calls on heads if I can swing it for 1000$ I wanna do it all this winter with the cam etc