New engine ideas anyone?

[Bart4]

Hey guys I have a 79' CJ5 with the AMC 304 , I am thinking of investing in a new engine that is fuel injected, and has more horse power. I just installed a new Holley truck avenger 670 carb on this motor bc the one that was on it before was the wrong size. I have a 727 auto Transmission with a Dana 300 Transfer Case .

 

[Old Dog]

Hey guys I have a AMC 304 , I just installed a new Holley truck avenger 670 carb on this motor bc the one that was on it before was the wrong size.

IMO you still have the wrong size, the 470 would have been better for you.
As for a new engine there's lots of good ones out there. What do YOU have in mind. What are you going to use the jeep for?
If it were me I would go with a 4.3 vortec, they have good power and get decent mpg.

 

[crscrkcj]

How about a small block 400 Chevy. My brother has one in a 65 Pickup. They are very compact and run great. Stay away from the larger AMC engines. Too hard to get stuff. Chevy parts and mod kits are readily available. Check out the Novak site.

 

[xj287]

This is probobly a stupid question, but why not just rebuild the AMC 304 to match the power numbers you want? There are plenty of aftermarket power parts including TBI fuel injection kits readily availible.

The AMC 304 's are simple, rugged and reliable, and have enough internal strenght to handle up to 500 horse power with out major upgrades. And dont forget this simple rule about carb. selection...NEVER install a carberator that has a CFM more then double the CID of the engine....It will cost you far more low end torque then you gain in top end horse power.

 

[jswatson0917]

I've seen a couple with corvette engines in them

 

[Bart4]

IMO you still have the wrong size, the 470 would have been better for you.
As for a new engine there's lots of good ones out there. What do YOU have in mind. What are you going to use the jeep for?
If it were me I would go with a 4.3 vortec, they have good power and get decent mpg.

Well I was afraid that it may be a little big, let me ask you this when I press the throttle to the floor from stop to go the engine wants to die, but if I ease into it I can hammer it down all I want going down the road. Does this have to do with a timing issue or do you think it would be solved by adding the 470? By the way all this jeep is for is playing in the woods with, climbing hills a little mud no serious rock climbing ect.. But however it climbs good and all but basically has to be at a slow climb pace slowly easeing into the throttle then it has like a burst after it gets past that first initial flow of petro??? Im puzzled guys help me.

 

[Old Dog]

Well I was afraid that it may be a little big, let me ask you this when I press the throttle to the floor from stop to go the engine wants to die, but if I ease into it I can hammer it down all I want going down the road. Does this have to do with a timing issue or do you think it would be solved by adding the 470? By the way all this jeep is for is playing in the woods with, climbing hills a little mud no serious rock climbing ect.. But however it climbs good and all but basically has to be at a slow climb pace slowly easeing into the throttle then it has like a burst after it gets past that first initial flow of petro??? Im puzzled guys help me.

This is a problem many truck avenger owners have. Yes the 470 would be better.
is your moter stock ?

 

[Bart4]

well it was rebuilt 3 years ago with new high torque cams thats about all I know.

 

[Old Dog]

I had a 670 on my 350 with a O2 guage. I found mine was leaning out when you went WOT from a stop. I solved my problems with a 50cc pump, different pump cam, larger squarters, smaller primary jets, and a different power valve.
The power valve made the biggest difference, it has to match the vac.signal the engine is sending to it.
The Holley site has lots of tuning info.

After all this I went tbi and I'll never go back.

 

[xj287]

https://secure.pawengineparts.com/shoppingcart/AMC_Parts.html

Here's just a little of the high proformance stuff thats availible for your AMC 304 . I still think you could upgrade that engine far cheeper and easier then swapping in a chevy small block.

 

[BrockGrimes]

Affordable Fuel Injection:
Affordable Fuel Injection - AMC/Jeep Throttle Body Fuel Injection

You can buy it as a complete kit or scrounge up most of the parts.
I had scrounged everything from the local JY for about $50 minus harness and computer chip. Which was about $300 if I remember. So for less than $500 you could have a TBI setup if you dig around.

 

[Cheepjeep85]

i've always wanted to put a toyota i-force v8 into something. i had a 99 s-10 xtreme and i came very close to pulling the motor out of it and dropping in the yota motor but damn them things are expensive. and i know toyota in a jeep = blasphemy

 

[BajaEdition]

you know, wheeling is all about torque, and some of the best egines for wheeling have been some really ancient technology engines. Just look at the engine that made Jeep famous, a small 4 banger built on tractor technology. The reason is you need all the torque down low, high reving engines have a serious lavk of torque down low. The best engine I can think of currently having been produces is the 4.0 liter from the TJ era of Wranglers, it created 80 percent of it;s torque at idle, that is impressive.

 

[BrockGrimes]

That's why I like the Ford 410:
4V, 10.5:1 — 330 horsepower at 4600 rpm and 444 lb·ft at 2800 rpm.