4.3L question - Is it worth buying a set of Vortec heads to put on my 4.3?

[handloader90]

I have a 350 SBC (Non-Vortec) that I could use but as @TreeFarm mentioned this is for an old Jeep Willys.

Trying to make sure my engine/trans/t-case is short enough to leave me with a rear driveshaft.

For now I will keep the Non-Vortec heads on the 4.3L and just run it, if I have issues later on down the road I will replace with Vortec heads or just find a '96 or new Vortec engine... probably cost about the same or less for a whole used engine than buying the heads would.

I paid $250 for this engine, was told it was running by the older gentleman that I bought it from. He didn't seem like the type to lie about it.

I'm gonna be running a 2 barrel intake off of a marine engine that has the carb pattern for a Rochester 2G and using an adapter to put one of my Motorcraft 2100 2 bbl carbs on.

I was originally going to purchase an Eddy intake and use a factory refurbished 670 CFM Holley Offraod Truck Avenger and jet it down. Holley sells the 670 CFM factory refurbished on eBay for half of what a new one costs, would have went with the 470 CFM but it costs the same new as the 670 CFM and the next larger size but they don't sell the refurbs for the 470 on eBay.

 

[handloader90]

There's the 4.3 the day I picked it up.

Long block a few days later.

Willy's after I found a set of new tires on Craigslist for dirt cheap... got a set of 6 that came off of a dually with 60% or so tread for just over $100.

Haven't looked up the weight on one of these old things but I move it around in the garage by myself all of the time and it takes zero effort.

I've got an old beat up 22 gallon fuel cell, bladder in a box style that I'm planning on mounting in the back of the tub.

I've already picked up a set of narrow track early 70's Jeep CJ5 axles that will give me an open knuckle axle up front and a centered differential in the rear. Factory set these up with a closed knuckle Dana up front and an offset Dana 44 in the rear.

Planning on running a 4.3L/SM465/Dana 300

I've got the 4.3 and I've got x2 SM465's. Gotta pick up a Dana 300 and adapt it to the 465, easy enough.

The Dana 30 and Dana 44 share the same ball joints and such so I'm planning on running Chevy Dana 44 Flat Top knuckles and Chevy brakes with JB7 caliper and a CJ rotor up front.

The rear will get the same CJ rotors put onto the flanged shafts and I have a weld on caliper bracket that will have a JB6 caliper on it.

Just gonna be a fun toy for cruising around town and hitting that washboard up in the mountains.

 

[handloader90]

Hes stuffing it in a flat fender. so not a lot of room. yes a 350 fits but the extra 5" of clearance from a 4.3 is a god send in my opinion

Also. I believe I just saw the build thread on your on Jeep forum... I believe that is the name of the forum.

I saved all of the pics for reference, the pic below if from the thread.

Just curious who's belt drive you used up front? Been looking at different ones, I've also been looking at high water flow ratio pulleys but March Performance want more for a set of pulleys than what I bought the entire engine for.

I'm missing parts of the factory serp setup and would prefer to have some bling on the engine anyways.

Also what year/model of Yota did you're steering box come from?

 

[TreeFarm]

Also. I believe I just saw the build thread on your on Jeep forum... I believe that is the name of the forum.

I saved all of the pics for reference, the pic below if from the thread.

Just curious who's belt drive you used up front? Been looking at different ones, I've also been looking at high water flow ratio pulleys but March Performance want more for a set of pulleys than what I bought the entire engine for.

I'm missing parts of the factory serp setup and would prefer to have some bling on the engine anyways.

Also what year/model of Yota did you're steering box come from?

View attachment 253543

Oh man I forgot all about that thread or any build threads for this thing. I have tons and tons of pics so if there is anything you want let me know.

The belt drive I pieced together myself. Im running a SBC long water pump. So I have crank and water pump pulleys for that application. Mine speedway motors brand ones. The Alternator is a summit racing house brand alternator bracket with an unknown pulley on the alt. Its actually the alt that was used to convert the old 4 banger to 12v and I havent replaced it yet. The Power steering pump is a TC style pump form a 4.0 XJ. Mounted on a KRC type 2/TC style mount that bolts to the front of the cylinder head. The pulley off of that is just some random one off of summit racing that had the correct shaft bore.

The steering box is off of a 86-95 4x4 IFS truck/suv. All of the power steering 4x4s are the same. the 2x4s are different. Im using a Sky offroad Flat pitman arm tapered for "1ton" gm joints. The whole system was adapted to -6 AN and tapped for hydro.

Here is a link to most of my pictures, A ton of them are just documenting original parts so I could sell them. I dont know if it will actually work though so just try it and let me know Willys mb

 

[TreeFarm]

There's the 4.3 the day I picked it up.

The Dana 30 and Dana 44 share the same ball joints and such so I'm planning on running Chevy Dana 44 Flat Top knuckles and Chevy brakes with JB7 caliper and a CJ rotor up front.

I think that you will find that D30 ball joints press into the inner C and d44 ball joints press into the knuckle. Unless the older D30s are different. Ive only dealt with modern unit bearing 30s.

 

[handloader90]

Oh man I forgot all about that thread or any build threads for this thing. I have tons and tons of pics so if there is anything you want let me know.

The belt drive I pieced together myself. Im running a SBC long water pump. So I have crank and water pump pulleys for that application. Mine speedway motors brand ones. The Alternator is a summit racing house brand alternator bracket with an unknown pulley on the alt. Its actually the alt that was used to convert the old 4 banger to 12v and I havent replaced it yet. The Power steering pump is a TC style pump form a 4.0 XJ. Mounted on a KRC type 2/TC style mount that bolts to the front of the cylinder head. The pulley off of that is just some random one off of summit racing that had the correct shaft bore.

The steering box is off of a 86-95 4x4 IFS truck/suv. All of the power steering 4x4s are the same. the 2x4s are different. Im using a Sky offroad Flat pitman arm tapered for "1ton" gm joints. The whole system was adapted to -6 AN and tapped for hydro.

Here is a link to most of my pictures, A ton of them are just documenting original parts so I could sell them. I dont know if it will actually work though so just try it and let me know Willys mb

Just looked at every single pic in that link lol.

You you have a MFG and P/N for the headers?

Also, do you have a P/N for the pilot bearing that you used?

 

[handloader90]

I think that you will find that D30 ball joints press into the inner C and d44 ball joints press into the knuckle. Unless the older D30s are different. Ive only dealt with modern unit bearing 30s.

From what I've reading the old Dana 30 and Dana 44 axles share the same specs where the knuckle meets the inner c.

I called Reid Racing just to verify and they've told me the same thing.

I do know that the newer stuff out of XJ's, TJ's and JK's don't share the same stuff as the older axles.

Reid said I could use an old school 44 knuckle on the old school 30 but could not use a newer 30/44 knuck on the older axle.

 

[TreeFarm]

Just looked at every single pic in that link lol.

You you have a MFG and P/N for the headers?

Also, do you have a P/N for the pilot bearing that you used?

The headers are Sanderson 90* headers

The pilot bearing will depend on what year engine you have. I dont recall what year it changed but the crank inner diameter changed so that will determine what pilot bearing you need. Measure it and that will tell you what one you need. Or give Novak Conversions a call. They have all the ones possible and are good people

oh, I dont know if I mentioned it before. IF you ditch the serp setup. You need to change the watepump as serps use reverse rotation. Just find a sbc pump that has the ports you want. Im pretty sure mine is for a 70s square body.

Also. make sure your harmonic balancer actually lines up with TDC, the blanacers on these things like to spin at the rubber and there are multiple different marking versions out there. Use a piston stop tool to find true TDC and then get a Timing tape for the balancer since probably doesnt have timing marks because of EFI

 

[vandelay industries]

i know my opinion is that the stock heads would be just fine, but i'd like to mindmeld with you concerning your choice of intake. But maybe tomorrow as it is getting late.

 

[handloader90]

i know my opinion is that the stock heads would be just fine, but i'd like to mindmeld with you concerning your choice of intake. But maybe tomorrow as it is getting late.

You think there will be issues with the intake?

 

[vandelay industries]

That intake will be alright, i suppose. But i feel there are probably better intakes. Do you already have the 2bbl intake?

 

[handloader90]

That intake will be alright, i suppose. But i feel there are probably better intakes. Do you already have the 2bbl intake?

It currently has a TBI intake on it, I have a GM TBI to 2300/350 pattern adapter but that combo will be way too tall, the TBI intake is very high profile, the adapter is 1.75" tall and then the carb on top of that is about another 5" or so with no air cleaner on it... this would require me to cut a big hole in the hood. I don't feel that a w barrel carb deserves to stick out of the hood lol.

A buddy is bringing the marine intake tomorrow, it is basically going to be free to me. I also have a 2 barrel Rochester to 2300/350 pattern adapter for it which I believe is .50" thick. This intake is very low profile compared to the TBI intake and I believe that the carb will be better suited on this intake.

I'll snap some pics when I get a chance.

 

[handloader90]

I would love to do the Eddy intake and the Holley OTA carb but it's $500ish that I don't HAVE to spend.

I believe that the 2 barrel Motorcraft carb will flow enough CFM for the unmodified 4.3L.

 

[diesel4me]

Dirt and oval track racers around here ran 2 bbl carbs exclusively,the rules prohibited 4 bbl carbs in many classes...some did use the 2100 series Holley/Motorcraft carbs on small blocks as well as both sizes of the 2GC Rochesters,I think those are plenty enough CFM for a 4.3 V6..

Leaner is meaner as the old racing saying goes,much of the time..

I had a 2100 Motorcraft on a 350 chevy for a while and it ran very well..

GM even used the 2GC on 400 small blocks and some 1969 396 big blocks too---a friend had a '68 Olds Delmont 88 with a 455 ,and a 2 bbl carb factory,it had no trouble roasting the tires--in fact if you look at the torque specs on those engines,the 2 bbl ones had more low end torque than the ones with a Q-jet..less HP,but more torque..

 

[handloader90]

Dirt and oval track racers around here ran 2 bbl carbs exclusively,the rules prohibited 4 bbl carbs in many classes...some did use the 2100 series Holley/Motorcraft carbs on small blocks as well as both sizes of the 2GC Rochesters,I think those are plenty enough CFM for a 4.3 V6..

Leaner is meaner as the old racing saying goes,much of the time..

I had a 2100 Motorcraft on a 350 chevy for a while and it ran very well..

GM even used the 2GC on 400 small blocks and some 1969 396 big blocks too---a friend had a '68 Olds Delmont 88 with a 455 ,and a 2 bbl carb factory,it had no trouble roasting the tires--in fact if you look at the torque specs on those engines,the 2 bbl ones had more low end torque than the ones with a Q-jet..less HP,but more torque..

2 bbl is definitely the planned route for now. The reason I'm leaning towards the MC2100 is that it can be modified with gasket material and a few little other things and it will basically run on it's side. I can't seem to find a 2100 in the junkyards due to me being too lazy to go and also as you stated they're big in the dirt track community. I find them on ebay in various conditions for what I consider reasonable.

Now @vandelay industries has brought up something that I am interested in, the marine intake. I don't know much about the intake besides from what I've seen in person. It is cast iron, it currently still has a Rochester carb on it, 2GC I believe but I could be wrong, the only Rochester I have ever dealt with are some good ol howling Q-Jets. It has the proper bolt pattern for my Non-Vortec heads.

Other than that I couldn't tell you anything, I'm going to assume that it will deliver the A/F mixture from the 2 bbl that I will use fine but again I don't know enough about it.

 

[handloader90]

@vandelay industries

Here is a pic of the 4.3L with the TBI intake in place, there is a box of nails acting as my TBI to 2 bbl adapter (it's measures in at 1.75" thick, same as the adapter) with a MC2100 atop.

This combo is very tall and it looks ridiculous to me.

 

[handloader90]

I have a local friend that has a mill and he said he could knock the TBI intake down for me but I'm thinking that we could only take it down maybe 1"... that isn't gonna be enough.

 

[kgblazerfive]

So why not just run the TBI ? What would be the reason to go to a carb ?

 

[handloader90]

So why not just run the TBI ? What would be the reason to go to a carb ?

I just don't want to use TBI.

Reason for the carb is I already have a few collecting dust in the garage and basically a free intake to slap one on. The adapter cost me $40.

The TBI is incomplete, the only thing I have is the throttle Body. I don't know much about TBI and I don't know where to start with missing components.

This Willys and everything that is going into it is going to be as low buck as possible. I've sourced everything thus far (minus an EZ Wiring Harness) off of Craigslist for bottom dollar prices.

Been trading a little here and there and using stuff that's been sitting in my garage.

If it's some that I don't absolutely have to spend money on or if I am able to spend the minimum amount possible for something decent that will help me meet my end state then that is the route I will be taking.

 

[diesel4me]

I'm thinking that marine manifold was probably for a "Dual-Jet" 2 bbl,GM didn't use 2GC's much after 1978 or so--but maybe the marine applications did...(Mercruiser bought GM's 307 V8's for marine engines and used them for years after they stopped putting them in vehicles in 1973)...

A Dual-Jet carb looks much like a Q-jet with the secondary barrel area that is "solid" metal,no rear barrels ..