First post yay

Anyway, I'm going to be getting a K5 blazer at some point within the next couple years, and I'll eventually want to swap in a built motor in to give it more oomph preferably around the 450ish wheel hp, and in my research the best way for me other than an LS is a 383 stroker

(i don't want to have to deal with computers and PCMs to tune the rig and the local junkyard isnt the greatest spot for choices except for a wrecked Escalade with an lq9 in it with an unknown amount of miles and i don't want to take the risk with that)

So im compiling a build sheet so i know how much i need to save up over the time to build the motor to swap in, ive come up with some listings of stuff that looks good and in my beginner knowledge looks compatible and would make hopefully around my target power

Block and rotating assembly from Skip white performance comes with forged internals and prebored and clearanced so its ready for heads intake, cam and carb and if i wanted i could run a power adder of which im leaning towards nitrous or a procharger. i can choose between -7.5cc pistons or flat tops which brings me to heads

AFR 195cc heads with 65cc chambers which from another forum people said would keep the rig streetable and depending on what cam i pick could make upwards of 500hp and with a calculator to help with figuring out compression id be making about 10.5:1 with -7.5 and 11.5:1 with flat tops and 91 octane isnt badly priced around me only about ¢20 more so running that isnt a problem.

And from the same forum post or at least same forum for someone with a similar build sheet i believe i saw someone recommend to use Edelbrock's "rollin' thunder" cam with 296/300 duration and lift of .539/.548

​​​​​​Any carb recommendations, changes or things im missing?

 

Welcome!

This sounds like it will be a great build!!

 

I have actually had your 383 in my S10 for 8 years. Because Skip White uses pistons with a different compression height, you will want the 10cc dish with 64cc AFR Eliminator 195s, giving CR of around 10.4:1. Higher than that and you will start having trouble with detonation on the street using pump gas when hot. Then you lose power backing off timing. Better to have CR matched to what engine can handle on pump gas with optimum timing. With aluminum heads, that is around 10.5:1 on 92-94 octane Premium. I always raced running 94 octane Sunoco. Now, back on the street any premium will do. My CR is 10.3:1.

Nix the big axx cam. With good heads you don't need so much cam to make power. And what you want in a big heavy vehicle is torque. Go with a Comp Cams XR274HR, 750 Holley or QF with vacuum secondaries, and a Edelbrock Air-gap dual plane intake. 1 3/4" primary tube headers (watch ports on headers - those AFR exhaust ports are big rectangular ports and you don't want ledges going into the headers.) There is your 500 hp build (after you get it properly tuned). You will probably need a 2200+ stall converter with that cam. Mine is a custom that stalls at 4100 rpm. really too much for the street but with the help of a big fancy trans cooler I'm making it work since the track closed in fall of 2020.

And here is the result with everything that I said except a 830 QF Double Pumper (because my vehicle is light) and I used a flat tappet XE274H cam. Engine in this form ran best of 11.1 sec.

Used to be the rule was $10 per horsepower (just for the engine). When I built mine in 2014 I found that to be true. Probably add 25% to that now.

Power adders are a fast way to break and/or ruin parts. There will always be someone faster anyways.

 

That reply was exactly what i was needing, thanks! keep an eye out on YouTube a while from now for a matte black k5 blazer cause that'll be mine

 

also i was thinking of putting 30 inch tires on it, do i have to change the front axle's gears to match the rear's if i swapped to 4:10's or something? nobody has an easy to find post about it

 

Yes, you must change ratios in both if you ever want to use 4WD. It would seem pretty silly to have a K5 Blazer with big tires and no 4WD. Good luck and best wishes.

 

Resurrection; Would this build work well in a L98 equipped C4? other than fuel injection i dont see any changes id need to make to the write up, i was thinking of going with FiTech's intake manifold replacement thing (part number "35301") for the EFI solution and hoping it fits under the hood or getting a small cowl hood for it

 

Cam is wrong for fuel injection, at least fuel injection with any kind of O2 sensor feedback. Need one of those mild 112 LSA cams for feedback fuel injection. Non-feedback fuel injection would suck on the street.

 

Cam is wrong for fuel injection, at least fuel injection with any kind of O2 sensor feedback. Contact FITech for recommendations on cam and CR.