More engine questions. Reconsidering the V8

More engine questions. Reconsidering the V8
Kirbot

Kirbot

Jeeper
Posts
198
Thanks
0
Location
South Jersey
Vehicle(s)
Cj7, 258 I-6, T18, D300, D30, Amc 20
Thanks for all the help I got in my "AMC 258 i6 / 4.2l vs 4 banger" topic.
But my questions and discussion drifted far away from the 4 banger, and maybe even the AMC 258 i6 / 4.2l , so I thought I'd start a new topic.

As the title says, I'm starting to reconsider the V8.
I realize the 4 liter 6 cylinder is a great engine, and has more than enough power in the woods.

But, well, who doesn't wan't a V8?
It takes a lot of power to turn 33" tires at a respectable speed, and the V8 has plenty of that.
And being carbureted, it would probably be much easier to install.
Now I'm thinking, whats the best way to do it?
Get a 360 out of a grand cherokee or wagoneer, with all the bits and pieces that go with it? Then get a heaver Transmission from ebay or a junkyard or something like that.
It doesn't seem that the grand cherokee/wagoneer V8 ever came with a manual Transmission . And I really don't wan't an automatic.

So that makes me wonder, would I be better off getting an old ford or chevy truck that already has a manual I could use?
Here's a good example.
1989 CHEVY 1500 350 V-8 2WD
I realize he doesn't say if it has a manual or not, but lets just assume it does.
Could I use that engine and Transmission in my Cj?
Would it be much more complicated than using the 360?


And here's a question thats sure to get a few laughs.
What kind of gas millage should I expect with a 360 or similer V8?
15 on a good day?
10?

I do have to use this as a daily driver, atleast for a little while, and I have to be able to afford to go somewhere now and then!
I'm talking about a CJ7 with about 3" of lift, turning 33" tires. Probably Mud terrains or something similar.
 
I got 14 outof my 327 and I am getting 12 with my 350 pushing 33 inch tires with alot of horsepower. I know I can get a few more mpg out of the 350 if I take the time to tune it better and get rid of the huge mechanical fan.
 
One thing to look at is the 2wd vs 4wd transmissions, they are different. You don't have to have a Transmission out of the wagonner to mate it to a 360. any Jepp Transmission that was behind and AMC V8 will bolt up to it. You basically need to decie what motor you want, and then get the parts around that. You can't go wrong any way, it's just different parts you need to match. Finding a complete donor, from engine to tc will be the best/cheapest for the short term.
 
Look for a setup from a 4x4, trannies are different, already set up for a t case.

But here is what disturbs me
you say" who doesn't want a V8" then ask what kind of gas mileage you will get.

Not much for a DD, will cost more to put in as extra torque, cooling etc issues need to be addressed. and cost more to maintain.

Also if punched that engine will soon start tearing the Jeep apart in ways a 6 never will.

It is a CJ, not meant to travel as fast as a V8 will, designed to be a slow vehicle and do trails. Want a hot rod go buy one but a Jeep is not a hot rod and can be damn scary when going fast, remember it has a very short wheel base and are known to flip easy.
 
what i'm gettin at is if he already has a T-176 , T-150 , T-18 he can swap in a AMC 304 , 360 fairly easily/cheap. granted the T-176 , T-150 may not be ideal for strength but it will get you on the road till you can afford to swap in a stronger tranny. i suppose if he has a T-4 /T-5 he could still do it but those won't last long at all
 
The T-150 is plenty strong, it's gear driven, however it's also a 3 speed, a T-18 with the granny low would be ideal.

That being said I've had my CJ5 with a AMC 258 i6 / 4.2l and 33" super swamper tsl's up to 80.

The AMC 304 and 360 are probably the easiest V-8's to replace a AMC 258 i6 / 4.2l , there are many well documented swaps you can read on the net, plus novak adapters has a great section on motor swaps. It's worth reading check it out.

I like the AMC 258 i6 / 4.2l , the V-6, and if I go into the V-8 world well the 401 is all that I want.

Considered the 4.3L chevy V-6? It's a nice swap also and can be found fairly cheap even in a doner vehicle.

Your current T-4 Transmission is a light duty Transmission and a V-8 will crush it, i'd recommend a sm420 or sm465 Transmission , both have a low 1st gear for crawling, the sm465 is
probably gonna be the easier one to find, look for pre 91 C/K chevy's, suburbans are you best bet. Novak adapters has kits to adapt them to you T-18 Transfer Case , and they will bolt up
with bellhousing mods to chevy or jeep v-8's.
 
Last edited:
I'm not looking for a "hotrod", but the engine thats in it now would need to be completely rebuilt. So before I dump all that money in this engine, I'm just looking at all the options.

Just putting a V8 in something doesn't make it a hotrod.
I mean most years are well under 200 hp, from what I've read, some of them were as little as 140 hp.
My parent's van is (considerably) more powerful than that!

With 3.54 gears and 33" mud tires, I don't expect to it will be the quickest thing on the rod.

This won't be a daily driver forever, eventually I'll need something that gets better millage no matter what engine I use, and thats why I'm not overly concerned about it.

I intend to have this jeep for a long long time, and I don't wan't to always regret not going with the best engine.


Having to come up with a better Transmission is what scares me since I do have a T-4 , I guess I just have a lot more learning to do.

I've been considering a chevy or ford engine, but as I said, I have allot more learning to.
 
rebuild the 6 or buy a short block Keep this as simple as possible. The next one can be a V8. Make this as easy on yourself as possible.:cool:
there will be more than enough challenges to this project to keep you entertained with out reinventing the wheel.
IMHO:cool:
 
How much do you have to spend on this project?
let us compare cost
rebuild a 6, or get a rebuilt short block 1500 dollars
do the v8 mod, adapters, rebuild, tranny, v8, driveshafts, cooling system to match, mounts, welding, wiring, upgrades to support v8 etc. ( I can list more) but we have over 4 grand to do it correct.
Conversions can look real good when seeing them looking at the cost of just 1 item, but the reason project vehicles are a dime a dozen on Craigslist is because so many people start a project, and after using up the funds they find that the project is just started and is going cost 3 times as much.
 
IOPort51 said:
there will be more than enough challenges to this project to keep you entertained with out reinventing the wheel.
IMHO:cool:
Click to expand...

Hmm
You've got a good point there.

BajaEdition said:
How much do you have to spend on this project?
let us compare cost
rebuild a 6, or get a rebuilt short block 1500 dollars
do the v8 mod, adapters, rebuild, tranny, v8, driveshafts, cooling system to match, mounts, welding, wiring, upgrades to support v8 etc. ( I can list more) but we have over 4 grand to do it correct.
Conversions can look real good when seeing them looking at the cost of just 1 item, but the reason project vehicles are a dime a dozen on Craigslist is because so many people start a project, and after using up the funds they find that the project is just started and is going cost 3 times as much.
Click to expand...

The only way I could do it would be If I found an engine that doesn't need rebuilding.
I saw one Wagoner on craigslist for $900 that only had 30 something thousand miles on it.
If I got something like that and sold all the rest of the parts, hopefully I'd get the cost of the engine itself down to a few hundred.

I really wan't to keep the cost of the engine as near to $1000 as possible.
But I guess that just won't happen with a v8.


Please
Keep talking
I gotta thick skull, it takes a while to beat some sense through it...
 
a engine swap is going require around 2 or 3 grand in parts to make it fit the rest of the jeep. You ill need a new radiator to cool the v8, new driveshafts to fi where every thing ends up, adapters to fit the engine to parts, new motor mounts, custom fab work for the new cross member, radiator, and mount positioning. It will need a lot of going to parts houses and finding this and that to make it work, as well as having to buy new brakets for everything that hangs onto the engine. You will have to rewire and if it comes with EFI a computer and new wire harness for that. Then the jeep will be down for about 6 months as you fit and pull fit and mod and such until it is done, after that quite a few test rides just to find the bugs.
1000 dollars is just the beginning, it will cost 3 times that more before finished
I suggest rebuild the OE engine
 
I do not remember what the problem with the motor that is in it.
could you address that once more??:cool:
 
I bought a Jeep that had the v8 swap done along with a T-18 tranny. I then swapped out my body, axles, suspension cleaned up the frame, replaced the brake lines and hardware. Then I put toegther the other Jeep and sold it for the same price I bought the doner for, walla!! Free V-8 swap with alot of elbow grease. Of course I proceeded to blow up that motor a year later and then build another small block that cost me a small fortune.
 
BajaEdition said:
a engine swap is going require around 2 or 3 grand in parts to make it fit the rest of the jeep. You ill need a new radiator to cool the v8, new driveshafts to fi where every thing ends up, adapters to fit the engine to parts, new motor mounts, custom fab work for the new cross member, radiator, and mount positioning. It will need a lot of going to parts houses and finding this and that to make it work, as well as having to buy new brakets for everything that hangs onto the engine. You will have to rewire and if it comes with EFI a computer and new wire harness for that. Then the jeep will be down for about 6 months as you fit and pull fit and mod and such until it is done, after that quite a few test rides just to find the bugs.
1000 dollars is just the beginning, it will cost 3 times that more before finished
I suggest rebuild the OE engine
Click to expand...

Hmm, I guess I really should just forget the 360.
I really don't think I can come up with that much more money, maybe someday.

IOPort51 said:
I do not remember what the problem with the motor that is in it.
could you address that once more??:cool:
Click to expand...

I might be overestimating how bad it is, not really sure.
I mean't to get a video of it running yesterday but I didn't get to it, maybe today.
It runs, even starts up pretty easy.
But, the main problems are, burns a ridiculous amount of oil, it just billows smoke.
I'm pretty sure one cylinder isn't firing, the bearings sound awful, and, if you floor it, it doesn't have ANY power, and it makes a rather unusual sound, kinda hard to describe. Sort of a "hwa wa wa wa"

It actually has MUCH more power at just half throttle.
From what I read I think the last problem has to do with the carburetor, but I'm not really sure.
 
Kane said:
I bought a Jeep that had the v8 swap done along with a T-18 tranny. I then swapped out my body, axles, suspension cleaned up the frame, replaced the brake lines and hardware. Then I put toegther the other Jeep and sold it for the same price I bought the doner for, walla!! Free V-8 swap with alot of elbow grease. Of course I proceeded to blow up that motor a year later and then build another small block that cost me a small fortune.
Click to expand...

Interesting Idea

I don't know, but right now I'm thinking I might do better just getting the engine I have running.
 
You can pick up a 4.6L short or long block and it'll be a fun vehicle.
Like suggested for ease of maint. and to get it back on the road a
stock or almost stock rebuild is the way to go if cost is an issue.

A AMC 304 or 360 is a fairly easy swap but that Transmission is gonna bite it behind
a V-8 and there's extra cost. Like Baja pointed out there is more cost
involved than just a motor, it's all the small :dung: that will nickle and dime
you to death.

Think about all the $5 items that you'd need, before you know it $5 items
turn into $500 totals.
 
Just two more questions??
Do you want it to run and would you like to learn something about being a mechanic.
I would say that you have enough to work with to make it run decently and there is a good possibility that if you took this on in small chunks you could make it happen with out pulling the engine.

One more question, is that a weber carburetor??:cool:
 
You must log in or register to reply here.

Jeep-CJ Donation Drive

Help support Jeep-CJ.com by making a donation.

Help support Jeep-CJ.com by making a donation.
Goal
$200.00
Earned
$0.00
This donation drive ends in
Donate
Back
Top Bottom