dumb I6 to V8 question

[raser13]

for those of you that have been doing this a while this is going to sound dumb. i'm looking at getting a CJ8 /scrambler tomorrow. right now it has the AMC 258 i6 / 4.2l I6. i'm going to be pulling that motor for my CJ5 that has a rod knocking. i've stockpiled a couple of 304s for a 73 javelin project car that i have. i only need one for that. so one of the other ones can get rebuilt and be slated for the larger scrambler. i know that it'll bolt right up to the Transmission with no problem. the question is with the motor mounts.

what do i need to change out to make it except the v-8? the metal supports that bolt to the frame? the metal attachment points on the motor to go from a car to a jeep set up? just swap the mounts? is there some where to get said parts? or do i have to get them from some one that has a v-8 parts jeep? or will it all just bolt together easy peasy?

any help would be great. thanks for looking and for any help

 

[Lumpy Grits]

AMC 6 to 8 is a bolt in deal.
You'll need AMC type V8 motor mounts.
Most likely you will need to go to a larger radiator also.
LG

 

[raser13]

I was planing to upgrade to a full sized jeep radiator and electric Taurus fans for cooling.


So I can still use the car metal mount to block parts, order a set of jeep V8 motor mounts, and use the existing metal mount to frame pieces that the six used? It seems to easy. There has to be some crazy thing to get in my way.

 

[HackFabrication]

Jeep put the AMC 304 in the CJ. For the most part it's a straight forward swap. Start trying to stuff other engines in, and it can get complex. And expensive.

 

[raser13]

Nope I was just going to put a 304in my new scrambler. I was hoping it would be easy. But I didn't think it would be that plug and play.

 

[raser13]

What the heck is that in there anyhow?

 

[CJim7]

I was planing to upgrade to a full sized jeep radiator and electric Taurus fans for cooling.


So I can still use the car metal mount to block parts, order a set of jeep V8 motor mounts, and use the existing metal mount to frame pieces that the six used? It seems to easy. There has to be some crazy thing to get in my way.

You will need the motor brackets for a CJ. When I swapped in my 401, I had to change those brackets as they were for a J-truck. I don't know if the Jav used a different bracket, but I would almost bet it did.
And then, obviously, the frame mounts for a AMC 304 equipped CJ.
You will also need to swap the fuel line over to the driverside. I did this by extending the fuel line to the front clip and bringing it just under the radiator, crossing over, and then on to the pump. I used braided rubber fuel line for this...easy.

 

[raser13]

ah ha! i knew there would be a catch! it all seemed to easy. thanks for the info looks like i'm going to be starting a search for both sets of metal brackets for a V8 cj.

 

[HackFabrication]

What the heck is that in there anyhow?

Ford Racing 5.0L. GT40 aluminum heads, GT40 tubular intake with a 3/8" spacer, 65mm TB, 24# injectors, 'B' cam, and Ford Racing F150 stainless steel headers that have been JetHot coated. Running an A9L computer that has a chip and dyno tuned. Don't have the dyno sheet, but it's probably make 350+hp to the rear axle with this combo.

Yeah, it's a bit of overkill, but then there are guys running BBC, LS1's, and goosed up AMC 401's in their CJ's....

 

[mtnwhlr]

Soon to be seen at a dragstrip near you.

 

[raser13]

i could see that set up in something like my javelin. but in a jeep! why would you need all that in a jeep?

 

[Lumpy Grits]

i could see that set up in something like my javelin. but in a jeep! why would you need all that in a jeep?

Anyone, that asks that-Would NEVER, understand the answer.



LG

 

[Hedgehog]

Hack - You need to take that jeep up to Oklahoma City and challenge the "Dung Beetle" to a street race. The camera crew on Street Outlaws would eat that one up, A CJ takes on a VW bug. The problem would be the Dung Beetle can really get down the track.

 

[mtnwhlr]

i could see that set up in something like my javelin. but in a jeep! why would you need all that in a jeep?

Many years ago a friend of mine swapped his AMC 304 for a 401 out of a Javelin and put a small lift and 32's on it. After taking it 4wheeling he said he almost needs to put a block under the gas pedal or he is going to flip it. And after about a year he ended up selling it because that 401 had pretty much wore everything out and he wished he had never did it.

 

[Lumpy Grits]

My son has a 'built' 401 Interceptor in his '5'.
Puts allot of street racers back on their trailers and has no issues with any sand dunes.
Man has got to know his limitations...........
LG

 

[HackFabrication]

Man has got to know his limitations...........
LG

Yup. My limitation is being a 25 year old, stuck in a 65 year old body. Reaction time isn't what is used to be. And as I recall, it wasn't all that good 40 years ago.....

 

[Lumpy Grits]

Yup. My limitation is being a 25 year old, stuck in a 65 year old body. Reaction time isn't what is used to be. And as I recall, it wasn't all that good 40 years ago.....

We must be brothers then......
LG

 

[hagar]

Just another AMC 304 under the CJ5 hood down the street from me.

 

[Hedgehog]

I certainly can see the thrill of big horse power. But I have to ask, how in the world can it be used in a vehicle that gets squirrely at speeds above 80? On the Oklahoma Street Outlaws program they had a glimpse of a WWII Jeep that was set up for street racing and that thing was impressive, it just sort of humkered down like a well set up pro-mod hooked and flew down the road ... unfortunately it lost the race, that didn't take away from how impressive it really was. That thing was low lean and mean, unlike our rather high and narrow CJ's.

 

[HackFabrication]

I certainly can see the thrill of big horse power. But I have to ask, how in the world can it be used in a vehicle that gets squirrely at speeds above 80?.

Stop light, to stop light....? Blasting up a sand dune....?

In all truth, I've got that engine, because it was available. Low miles (probably under 2k), lots of extras, etc. It was a lot cheaper than buying a new crate motor and adding the 'trim'. I had two used Mustang 5.0L engines sitting on the floor, but both would have needed freshening up. Economics dictated the purchase.

Then the fun really began....