Stockvs Ram horn manifolds

Back in the days of fuelie heads, Rams were the best bang for your buck.

The way they point downwards for a 4wd and routing the wires underneath just seemed a bit odd to me for my Blazer.

We have a lot of stock manifolds get warped here in MT due to extreme cold, so heavy duty castings are good.
Was very surprised when the box arrived how thick they are vs OEM.

That looks gret CalSgt. Nice work.

All the discount aftermerket castings researched, had too much pot metal in the iron.
Very little Nickel. Some would barely hold a magnet.

Same problem with the power steering pumps from over seas. Poor castings.
The $50 up-charge is where the quality casting P/S pump guts add up.


Here's the Hookers:

Driver's side from underneath.
The 1976 El Camino headers would not fit due to the 4wd axle on the passenger side.
Oil relocation would have been required to use them. So, once installed, it made sense to keep it, instead of running a cooler.

The Pipe wrap protects all the goodies better than expected on the 2 custom Down Pipes. (Not pictured).


Passenger side is way out over and past the starter. Using the fat style starter, (non-permanent magnets), would work no problem.

The smaller version starter from 94' (with permanenet magnets) has tons of room.
The bolts ar diagonal for the smaller starter. Every small block I have installed P-Mag, required at least one diagonal shim. My replacement 99' L31 engine requires 2 shims.

Some early blocks do not have diagonal starter bolt castings. You are stuck with the fat atsrter that can become heat soked and require replacement every year or two.

Choosing exhaust vs the fat starter is a definite issue you want to get correct.

During transmission rebuild, forgot the small starter shims, getting in a hurry to test.
Broke the end of the bendix snout right off, first hit of the key.

Luckily no damage to the ring gear.
_______________________________
Finally my plugs wires don't get burned from the Sanderson mistake, using the Hooker's.

When tacking the down pipe in the picture below, forgot to fully remove and protect my new Fragola Crimped ends PTFE braided transmission lines.

Four beads of Mig jumped 7-8 inches sideways and ruined them. Weld slag flies sideways, not down. Unbeleivable.

Now they will be cut and re-purposed for fuel lines to the TBI. $160 mitsakes add up fast.



The Blazer frame narrows, so Rams DP would get weird.

On the Pass side, it would super heat the frame and cook brake lines and starter wires using Rams. Not enough room, in my opinion.

Blazer is an odd ball if you search Summit for Ex manifolds.

So your issues might not be mine with a different C10/C20 frame design.

Rams are known to use the heat rise to draw the air from the exhaust very efficiently. If you can use them, you cannot go wrong with a real set of good cast iron Rams. They pull well.

Good luck finding them.

Would refrain from using the pot metal castings to avoid breaking the fragile Vortec 062 or aluminum cylinder heads in -20 to -40 climates, though.

Cracked heads are a known issue with Vortec OEM castings. Most aftermarket's are improved to some degree, but not all. Many heads are broken in the valve stem castings, Many are bnroken from manifolds warping.

The most important thing is to avoid the dreaded Snap-O tool for spreading the warped castings.

The #7 and #8 cast legs on OEM manifold's, are known to warp bad on the later year 87'-94' SBC's here.

SnapO sells a small hardened steel fine thread scew with wrench lugs to split the manifold using massive force.

It side-loads the bolt horrendously after they get started. Watched a few local mechanics use them in horror to fix somebody's engine on the cheap.

Doubt those heads lasted the winter after a few heat cycles.

New heads, warped pot metal manifold is a fail in my book. You tend to get what you pay for when it comes to quality cast iron.

Using a flap of inner tube and a few zip ties to block the tire splash under the steel wheel wells helps a lot.

You can find the OEM style splash shields, from LMC, if you need them to look restoration quality. $14-$18 in the 2024 catalog? Might be more now.



Whatever you select for manifolds, protect them as best you can from the huge puddle at the bottom of the off-ramp.

Your headers can warp when you exit the highway, hit the red light and freezing puddle, with red hot exhaust after running 75 mph.

Sheilds are often overlooked.

YMMV.

Couldn't fit these pics into the previous post.

OEM Manifolds:


The frame is no where near as narrow as the Blazer.




Stainless?
(Every manifold eventually shows signs of rust, even stainless, unless it's 316 $$$$$).
You guys tell me what it is?
Very cool bends.

The only new engine part is the driver's side manifold gasket, best of my knowledge.
Starts on the first turn, lil' pedal.


72K original miles.

Notice the smog ports are all blocked off by the factory?

Now you see how the CHEAPER OEM castings evolved from these HQ factory manifolds.
Look at the engineering and quality of these compared to everything else out there?
Probably too much $ for production ?

CalSgt said:

Vortec manifolds are quality stuff for being EGR manifolds, the 96-99 trucks were rated for 330 HP which is right below the H.O. 327’s.

Click to expand...

99.9% sure 96-99 L31 350 SBCs in that era were 255hp. That was a 30hp bump from 95, when they had 225 with TBI.

Frankenchevy said:

99.9% sure 96-99 L31 350 SBCs in that era were 255hp. That was a 30hp bump from 95, when they had 225 with TBI.

Click to expand...

Yup… you’re right, not sure where I got 330 from

Maybe I was thinking of one of the available GM crate motors from around that era.

RanchWelder said:

Couldn't fit these pics into the previous post.

OEM Manifolds:

You must be registered for see images attach

The frame is no where near as narrow as the Blazer.

You must be registered for see images attach

You must be registered for see images attach

Stainless?
(Every manifold eventually shows signs of rust, even stainless, unless it's 316 $$$$$).
You guys tell me what it is?
Very cool bends.

The only new engine part is the driver's side manifold gasket, best of my knowledge.
Starts on the first turn, lil' pedal.

You must be registered for see images attach

72K original miles.

Notice the smog ports are all blocked off by the factory?

Now you see how the CHEAPER OEM castings evolved from these HQ factory manifolds.
Look at the engineering and quality of these compared to everything else out there?
Probably too much $ for production ?

Click to expand...

Those were only in a couple years of squares and only with certain options. Very few examples of them left. Definitely better than the log manifolds.

PrairieDrifter said:

Those were only in a couple years of squares and only with certain options. Very few examples of them left. Definitely better than the log manifolds.

Click to expand...

I think they were only on 1 tons and G30's

This is to be avoided:


After watching this gentleman, fumble to save a few bucks, ask yourself if forcing the castings back in shape is worth it? Can you imagine the side load pressure on all 6-3/8" manifold bolts?

Cannot be good witha few extreme cooling cycles on those heads.

You do this and ruin your daily driver engine, you were warned.

If the manufacturer recomended welding them in place forever, one might have actually fallen for the cheap-o fix. I aslo see how getting your long time customer home cheap for another few months is a business model. They simply might not be able to afford replacement castings ot the installation costs.

Posted this to inform, not criticize anyone using these methods.
Now the forum member's can make an informed descision on best solution for their buck.

If it's your twice a year dump-run truck, this might save you a lot of money.

It's important to throw stuff away when it's wrecked beyond resonable use.
Not re-sell it to an un-suspecting buyer on a website or in this forum.

These are supposedly good quality OEM castings, in the video? IDK
The runners look enemic and too thin in the video.

The $100 pot-metal version castings might bend your head in half, if they shrink any more than these, in the video.

Buying used manifold's on our favorite used parts oinline market place, MAY result in buying somebody else's Junk, if you are not very careful.

Which is why real 2-1/2"x 1-5/8" Rams's are most likely a myth.
When you see them for $800.00 to $$1200.00 EACH, as a restoration quality numbered part, then you know they are the real deal.

Which makes sense.
They OEM HQ NEW Casting heads they might destroy are exactly the same cost EACH.

Same as Police Special TBI Injector's.
No such thing anymore.

Do not drink the Blue, Green, Red, Orange, Purple or Yellow Cool-Aide.
It ain't cool.