304 verses 258

304 verses 258

rr41mag

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Panama city florida
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04 dodge truck, 1966 chevy truck, 2012 rav4
And finally a 1981 jeep cj7 258 hardtop
I would really like to have the V8 but just cant seem to find one. I live in Texarkana and have looked as far as 200 miles out. So what would be the differences in the two? Would I notice that much more power with a v8? What are the differences in horsepower between the two stock from the factory? If I get this one with the six cylinder It will get dual exhaust, carb, intake, distributor and probably a new cam.


1981 Jeep CJ7 Renegade
 
I guess you mean you're looking for the whole jeep with a v-8?
I have both a AMC 258 i6 / 4.2l and AMC 304 versions and while AMC 304 does seem to have more lowend torque, I have not notice a big difference in power.
The v-8 definately has the wow factor but if I were going to race them side by side I'd put my money on the AMC 258 i6 / 4.2l .
 
Yes the common jeep seems to be the CJ7 with a six cylinder. Like I said though, I'll install a header etc, etc. It should be fine.
 
I found this on wiki. The AMC 258 i6 / 4.2l may have even more power than late AMC 304 's

The AMC 304 had a displacement of 303.92 CID (4,980.3 cc) which produced 210 hp (157 kW) in 1970-71 and was built starting in 1970.[5] Later models produced less power from the factory, going down yearly. 1972-78 models were rated at AMC 150 hp (112 kW). It was rated at 130 hp (97 kW) in 1979, the last year it was installed in passenger cars, and 125 hp (93 kW) in 1980-81, the last years it was used in Jeep vehicles.
AMC V8 engine - Wikipedia, the free encyclopedia
 
The AMC 304 was a factory option from 1972 to 1980 in a CJ hence the reason for the I6 being more prevalent. I have owned both and find that the I6 has more low end grunt than the V8 but the V8 is capable of producing more power. If you want to swap in an AMC V8 for the I6 it is a pretty simple job as you can basically use all OEM parts; you do need to move the passenger side motor mount but that’s it. Applicable smog laws may be more of a head ache than anything else.

I would focus on the overall condition and “goodies” on the jeep for the price and put the motor size 2nd.
 
going to look at a CJ7 in a little while. It has the AMC 258 i6 / 4.2l with a four speed and looks to be in really good shape. I'm not going to be concered any more about it having a v8 since part of the fun is putting performance parts on. There is another project jeep for sale in my town for $800 and it has a v8. I may just go look at it also. It's all there and would be nice to have a spare.
 

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