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rebuilding my 350, Whats the best setup for off roading?

deek

1/2 ton status
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I'm rebuilding a 76' 350 4-bolt main, its out of a 3/4 ton.

I know theres many of you out there that are highly knowledgable when it comes to these engines, thats why I'm asking you because you know what works & what doesn't.

I want to know wthat parts I should run to get great off road power. any little bit of info would be helpfull, like what carb, intake, cam, pistons & bore, even heads or valvs, (although vortecs aren't in the budget). thats another thing I also want to keep in on a lower budget.
 
Stock rebuild, low rpm cam for torque, good valve job, cloyes timing chain, clevite bearings, fel pro gaskets , speed pro rings, dual plane intake , q-jet and hei ignition with hot coil. Keep it simple, and it will live a long time. Most off roading doesn't require a built motor , and you sound on a budget. Just pay attention to detail and dont forget new oil filter adapter , those need replaced . /forums/images/graemlins/thumb.gif /forums/images/graemlins/k5.gif
 
Bottom end should be stock. Regrind crank, replace pistons, resize rods, use ARP bolts in the rods and have it balanced.

Block should be tanked, bored if necessary, line honed, and decked to zero so you can use good head gaskets and still have good quench.

Heads should be aftermarket units based on the budget. Match the chamber size to the pistons you use so you don't go overboard on compression. Cam should be SMALL.

If it's in the budget go for a stroker crank and pistons, it'll add some serious power to the entire buildup.
 
I would go for the vortecs because it isn't much more to pick up a rebuilt set than to have your stockers rebuilt. The heads by themselves are supposedly good for 30HP or so, stock early heads don't flow worth a crap. Keep your compression down because these days gas is getting worse and worse, 91 octane or not, it still will ping with most motors. Plus it is getting way to expensive to run premium all the time(don't ask how I know). Keep it around 9.1:1. Edelbrock performer intake, performer Q-jet, comp cams 260H cam or something close to it. I would wan't around 440" lift with a cam because max lift on vortec heads is about 450" and for a 350 440"-450" is plenty big. 210-215 duration. Leave the bottom end stock because SBC rods and crank are pretty stout pieces but have the assembly balanced, good HEI distributer. This combo should be good for 300HP no prob and last a long time. /forums/images/graemlins/thumb.gif
 
TRW 9:1 compression pistons

Doug Herbert H-beam connecting rods

Doug Herbert forged 4140 forged steel crankshaft

ARP rod bolts

Melling high volume oil pump

Melling steel oil pump shaft (with steel sleeve)

Cloyes Dual roller Timing chain

ATI super harmonic damper

Crane Cams RV camshaft and full valve train kit

ARP screw-in rocker studs (have heads drilled and taped for screw-in studs)

Edelbrock aluminum dual plane Performer intake manifold

Edelbrock Carter style carburetor (I am going get an argument on this)

Edelbrock shorty style headers

Mallory HEI four pin control module distributor

Moroso oil pan, timing chain, and valve covers
 
What is the budget?
It all boils down to HP=$$$
The nice thing about SBC's is they can be made to put out with little effort or big bux.
The key to good power is in the heads and the cam.
What heads are on it now? Casting# intake valve size.
First off be sure to have a good set of heads.
I'm on a budget as well with mine. I must have looked at 200 heads before I decided to go with a set of World Products S/R torquers. It's only a few $$ more for a set of those than get a set of used ones up to par.
I'm doing an inframe on my "new" crate engine.
I spent lots of time looking at different cams and settled on the Rhoads Hydra-solid cam set.
I'm just waitin on the Blazer bank to fill up a bit more so I can see how that cam works.
For an intake I have a Weiand Stealth that I was gonna use.
But being a square bore that leaves me with either an Ebrock or a Holley for a carb.
Good carbs for pavement duty but I am not impressed with em off road.
The Holly avenger looks like it would be a good match for my set up but it's over $300. A regular RPM manifold is about $150 or so and I have a couple of Q-jets off of 454's that are good builders and a kit is a hell of alot cheaper than a new carb.
My recipie..
350 4bolt main flattop pistons 9:1 or so
WP heads
Rhoads cam
Ebrock RPM Q-jet manifold
Q-jet
That's what works for me.
 
This is a kit from northern, take a look & tell me what you think. Hell even fill out the options that I should go with & cut/paste the check out page to me. Required (options STD.)

On the upgrade list check only things that you think i need, not just cuz its a big name.
 
no need to spend money on aftermarket rotating assembly in a 4x4 motor unless you are strokin it
even then stock 400 rods are perfect and IIRC you can then use off the shelf 350 pistons

low rpm grunt is where it is at, and reliable
I like compression, as much as can possibly be run
smallest CC heads you can find and if you need to use a dish to get the compression down that is good
increased piston surface area for the combustion pressure to work against
 
why the 'rpm' manifold?
it is very out of place for your extremely heavy vehicle
I have an ancient 2psp small runner dual plane and wish there was something similar still available

your intake pattern is perfect for an OHG propane mixer using a Holley base plate
that being said I am going to look for a Victor or torker to compliment my future turbo to go with my new Propane system

hard to beat the stock intake but the few pounds saved with a common and cheap aftermarket aluminum one is nice and BLING

I guess a long runner efi manifold is about as good as it gets for trucks
 
Basicly stock. You may want to get a set of World Products SR/Torquer heads, a RV Cam (Great low end power) I like the Weiand Action +, or Stealth intake intake manifold, and some Doug Thorley Tri-Y headers. Know what cc heads you'll be using when you order your pistons. Try for around 9 to 1 up to 9.5 to 1 compression. /forums/images/graemlins/deal.gif
 
[ QUOTE ]
why the 'rpm' manifold?


[/ QUOTE ]
For one it comes in a spread bore flavor.
Two: it has an RPM range that matchs the cam.
Three: it just looks cool.
 
[ QUOTE ]
[ QUOTE ]
why the 'rpm' manifold?


[/ QUOTE ]
For one it comes in a spread bore flavor.
Two: it has an RPM range that matchs the cam.
Three: it just looks cool.

[/ QUOTE ]Weiand Action plus
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I already have a stealth intake, swapping that for an action plus would be a step in the other direction.
/forums/images/graemlins/shame.gif
The action plus is a stock replacement manifold.
While it is decent enough it won't match the rest of the plant.
Although the cam is not a radical one it is still enough that I don't think a smaller intake will support the engine.
 
[ QUOTE ]
I already have a stealth intake, swapping that for an action plus would be a step in the other direction.
/forums/images/graemlins/shame.gif
The action plus is a stock replacement manifold.
While it is decent enough it won't match the rest of the plant.
Although the cam is not a radical one it is still enough that I don't think a smaller intake will support the engine.

[/ QUOTE ]The Weiand Stealth is a great intake. I only brought up the Action plus becouse someone was talking about a Edelcrap that was spreadbore.
 
the lowest point of the powerband is the only one that matters in a 4x4
if it is above 3000rpm a couple extra ponies dont matter
if it is being sucked down low every foot/pound counts
 
truck cam, vortec or aftermarket heads, truck friendly catb, maybe a roller system on the valve train
tri y headers and decent exhaust dont go above 10:1 compression

maybe some nice new Under drive pulleys from summit
 
[ QUOTE ]
the lowest point of the powerband is the only one that matters in a 4x4
if it is above 3000rpm a couple extra ponies dont matter

[/ QUOTE ]
Yep that is true.
That is why I have chosen that intake with the cam.
That cam is still new to the market and still has alot of unknowns to it. But from it's profile it has the capibility to make power from idle to 7000 rpms.
So it will start making power down low and keep a nice flat torque curve across the band.
It looks good on paper anyway, I'll just have to wait till I have it put back together and strap it to a dyno to see if it works as advertised.
On a side note the last time I was blasting up a dune it was not at 1500 RPMs, the same with with blasting up a gooey clay hill or across the mudflats.
Not everyone that shifts into 4 lo or high is trying idle over the rock of Gibralter.
But with that set up it should be just fine at the lower RPM's.
If it doesn't work out it's not that hard to try another component and see if it produces better results.
It is just a toy afterall. /forums/images/graemlins/wink.gif
 
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dont forget new oil filter adapter , those need replaced

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Please tell me more about this as I have a leak that is driving me nuts and I KNOW it's not the pan but it's leaking all over the filter. Could this be my problem? Educate me please /forums/images/graemlins/ears.gif /forums/images/graemlins/thinking.gif
 
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Please tell me more about this as I have a leak that is driving me nuts and I KNOW it's not the pan but it's leaking all over the filter. Could this be my problem? Educate me please

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Its not so much replacing it as a source of leaks. The bypass valve and the parts inside get dirty and the spring gets weak. You want the oil to go through the filter . In your case I would first check the rear of the intake, the oil pressure sender area, valve covers, and if newer the second oil pressure switch in block above oil filter. In some extreme circumstances it could even be a galley plug on back of block , there are a few real small freeze plug type things on back face of block behind flexplate/flywheel. If that was leaking it would come out of inspection cover though. Those get removed , holes tapped, and actual threaded plug installed. /forums/images/graemlins/k5.gif
 
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