buddhaz06

iTrader: (8)

Hi I'm currently trying to get ideas for a nitrous setup 4.8. Stock 80k mile short block, what heads and compression should I go with? I was thinking either a 243 head or milled 317's id like to spray 175-250. And also I see nitrous cams are in the .600 lift range, big 240-260 duration and rpm range of 2400-7200. Would a cam like that be way too big for a 4.8? Plan on running a victor jr with plate and elbow. Any input would be great! Only thing I have now is the 4.8 and I have 2 sets of 862 heads and some 317's

Fbodyjunkie06

iTrader: (10)

I wouldn't use 317's on a 4.8. 862's may be no problem if the valves are stock, I'd get a set of older 5.3 heads with the smaller intake valve.

dnkynrbk

iTrader: (34)

If you can find a set of LS6 243 heads that would be best.

buddhaz06

iTrader: (8)

Ya I think 243's would be the way to go

Why smaller 5.3 heads? Dont I want bigger valves?

Fbodyjunkie06

iTrader: (10)

Bore size and valve shrouding

Firehawk441

iTrader: (41)

That's what I would use. I wouldn't even consider a 5.3 head.

Fbodyjunkie06

iTrader: (10)

Because of the smaller valve?

Is this going to be a strictly nitrous motor?

buddhaz06

iTrader: (8)

243 head would lower my compression to 9:1. I think I'll go with milled stock heads so is not a dog on motor.

buddhaz06

iTrader: (8)

It'll be nitrous at the track. Want it t have a lil get up n/a

Fbodyjunkie06

iTrader: (10)

What CR would the 5.3 heads give you? Like I said at first I'd use the 5.3 heads on a 4.8.

Is this going to be a track only car?

Nitro Dave's Nitrous Outlet

iTrader: (25)

Im not sure what head would be the best option on the 4.8 so I am of no help there. I did want to say if you decide to go with a 243 head I have a set of ported and extremely milled heads I would make you a good deal on.

https://ls1tech.com/forums/texas-cla...243-heads.html

Firehawk441

iTrader: (41)

Accually, after re-reading the OP's 1st post, I'll take what I said back.
The OP wants a stock, 80,000 mile 4.8 with a Vic Jr. Intake and 240 + duration.
I'd rather not involve myself with this.

buddhaz06

iTrader: (8)

well the 5.3 heads and 4.8 heads are the same. 862's. stock is 9.5:1. i figure mill them just a little, and get a thinner mls gasket. prolly be between 9.7-10:1.

yes pretty much track only. it'll be driven to track, roughly 15 miles each way. im leaning towards a 580-590 lift, and iwant the victor jr because i want a metal intake and i see it being the best option, because i can run a carb style nitrous plate.

243 heads will lower my compression a lil much for me. i didnt realize they were 9.5:1 stock. a friend of mine made 305rwhp with a 224r cam and headers with his 4.8 pickup. and ive heard of several guys running 200 shot on 100% stock trucks.

Nitro Dave's Nitrous Outlet

iTrader: (25)