304 V-8 Mods, what do you have?

304 V-8 Mods, what do you have?
Canadian CJ 7

Canadian CJ 7

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Current Setup 1985 Jeep CJ-258, 6cyl -T-5 5spd 273 gears.
I recently purchased a AMC 304 V-8 with a Edlebrock Air Gap Manifold and I am looking at rebuilding it. Does anybody have a great AMC 304 there really happy with and what have you done to it, such as cam, timing set, roller rockers, 4bbl etc. 360's are hard to come by in my area, since I have a AMC 304 , I might as well build it up. My jeep is mostly going to be a street jeep with a bit of trail use. I want it to have a bit of get up and go. I also have a T-176 4 speed I am going to put into the jeep and replace the T-5 which I probably will break with the V-8. I am also going to change my gear ratio to 355 from 273 and replace my two piece axles with one piece axles. Any suggestions?

Brian
 
Yep. Unless you're counting on really pretty serious street racing, put in a high-lift, low-duration, low-overlap camshaft for flat hydraulic lifters. That'll give you a power band that starts good & low & reaches up to about 4500RPM. It'll also let it idle well.

What year AMC 304 is it? If it's an early AMC 304 , it'll have the highly prized high-compression small-chamber heads that cough up about 10:1 compression. More than you need... it'll start easier with the 9:0 compression you'll get from stock pistons & late-model heads.

If you want to always be fooling with it, go ahead & go to solid roller lifters. You'll just have to keep adjusting 'em, time & time again. Or... go with hydraulic rollers, which take custom-selected pushrods... but they don't buy you much unless you're reaching for 7000RPM. Me, I don't like spinning one of these V8s any higher than about 5KRPM without some really heavy attention paid to rotating mass & balance & specialty pistons... and then you're working with a very different camshaft that won't let your Jeep idle, and it's gutless on the trail where you're using the lower engine speeds.

How's that? :)

The AMC 304 , thoughtfully put together, will give you lots more poop than the AMC 232 i6 /AMC 258 i6 / 4.2l ... especially with any sort of 4-barrel on it.

Edelbrock seems to be making some pretty credible 4bbl carburetors these days. I haven't handled nor run one, but they seem to have some pretty good design ideas going there... and there's a lot of 'em out there so they can't be selling :dung: (bad word gets around FAST).
 
Hi Tim, I believe the AMC 304 is a 1973. That is a good deal for the cam and lifters. I had an Edlebrock 600 cfm carb with off road floats on my 79 CJ7 with a AMC 304 and loved it. Is Summit a good place to get performance parts for AMC? I live in British Columbia Canada, but I get all my parts from the USA and pick them up at the border. :)

Brian
 
I can't say whether they're BETTER than other places... but they sure are popular so they must be doing something right. :)

I was born right next to the BC border, in northern Idaho. Still got a lot of relatives up there - Mennonite country.
 
Tim did you ever go into British Columbia, you would have been near the Rockies, beautiful area. If you watched the Winter Olympics recently from Vancouver BC, I am about one hour east of there. I checked out Summit's website, it has a lot of AMC stuff. I don't know if Jegs is any better or not.
It would cost me three times as much to buy my parts up in Canada, so that is why I don't shop here. Gotta Love the US, get place to buy parts and vacation. :)
 
You get discounts at some of the vendors but i can't remember which I think you can find it in the "links" or talk to a moderator.:cool:
 
BC is a beautifull province i loved Vancouver island but Hongcouver was way to pricey for me i was offered a job there at the Rolls dealer it seems the courtessy car is the most common vehicle there and bodyshops are crying out for people :D
 
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Hey, a bear's trying to break into your house, SX! :D
 
I raced a AMC 304 for quite a few years in E Central Fl at the 100 yard sand drags.

My AMC 304 has a cross drilled, knife edged crank. The rods are ground and then shot peened and bushed full floating. Block is o-ringed. Heads are ported (port matched in the beginning) and flowed by Bo Laws (long time ago) and the Torquer II intake was matched at the same time. The intake is smoothed using Extrude Hone.

Many oil system upgrades.

Custom Lunati cam and springs with Harland Sharp rollers (1.7). True roller timing chain (had a PJ gear drive at on time - wish I never sold it).

Spent WAY TOO MUCH MONEY a long time ago - but wanted to race in the stock displacement class.

Adapted much of the hardware to a 390 I inherited but have since had to return the engine, now cranking up the AMC 304 again... :D
 
CJ that sounds like quite the motor you had. Are building another AMC 304 ?
I just ordered BJ builds an AMC. I might get some ideas after reading it. I am enjoying everyone's posts of their AMC 304 builds and experiences. :D

Brian
 
I still have the original AMC 304 in the garage. Until I get my 401 built, I'll be running that engine. The little AMC 304 will scare the heck out of you if your not prepared for it.
Being close to square (bore and stroke) it revs pretty high (only with an upgraded oiling system) and can put out some decent HP. You just have to get it breathing. AMC engines love to breath! :) The dog leg exhaust ports are second to none... :)
By simply CCing the heads, cleaning up the combustion chambers and port matching, you can really wake the V8 up.
 
Some great info here guys. CJ, I'll be tearing into the AMC 304 in the project I just got in the next couple weeks, and I'm sure I'll have lots of questions.:notworthy:
 
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