304 Performance Help or Suggestions

304 Performance Help or Suggestions
Canadian CJ 7

Canadian CJ 7

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British Columbia
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Current Setup 1985 Jeep CJ-258, 6cyl -T-5 5spd 273 gears.
Hi there, I have an opportunity to buy a stock AMC 304 V-8 and swap out my AMC 258 i6 / 4.2l I-6. It is going to be mated to a Tremec T-176 4 Speed Transmission . I am going to do a one piece axle swap and run either 354 or 373 gears. There are lot's of performance parts options. Has anyone built a great performance AMC 304 motor and what did you do to it? My jeep will be used mostly on the street and some trail use. I have put an ad out for a AMC 360 but nothing come up so far. So I am going a head with the AMC 304 .

Thanks, Brian

Briitish Columbia, Canada
 
Well you shot down my #1 performance mod for a AMC 304 - replace it with a 360! :laugh:

seriously, most anything that works for a 360 will work almost as well for a AMC 304 .
Edelbrock makes a 4 bbl intake to drop a performance carb on (I run a Holley Truck avenger 670 cfm carb)
Look into the Teamrush conversion for ignition upgrades, or a simple tune-up with quality parts will get you by.
headers work wonders if you can put up with their idiosyncrasies and routing. glasspacks or turbo mufflers work here.
You can get a mild RV style cam to wake the engine up a little if you want to go that far into it.

Basically, basic hot rodding tech, not anything real fancy will give a good bang for the buck....



(but it will all work that much better on a 360! :laugh:)
 
Oh what size tires are you planning on, to help pick the right gears?
 
I currently have 31 inch A/T, on my jeep. I might go up to a 33 inch A/T, once my tires wear out and once I install a 2.5 inch lift kit, with a 1 inch shackle lift.

Thanks for your advice, mylittlecj5.
 
I have a fuel injection conversion, HEI distributor, edlebrock 4 bbl manifold, mild cam and it is .030 and on the dyno it pulled AMC 232 i6 /295. It is mated to a T-150 and has 3.54 gears in it with 33 in. Mud terrains with one piece axles.

It is in a 5 and it gets up and moves. about 13-14 mpg give or take these days... I can't complain, it is a heck of a lot better then it was, with the rebuild there is a lot less leaking and now I know what I have under the hood. Next up... 401... skiping the 360.

cb
 
Thanks for the info guys, I would be happy with a AMC 304 putting out over 200hp, big horsepower means spending big bucks to prevent breakage. Certifiablejeep are you also running headers also? I was looking at either 354 or 373 gears with the one piece axles. Sounds like your set up is what I am going for, I am going to swap in the T-176 for my T-5 . I like a mild cammed V-8 over a I-6, just my preference. Anybody else got AMC 304 they are happy with and have does some great mods.

Brian
 
Canadian CJ 7 said:
Thanks for the info guys, I would be happy with a AMC 304 putting out over 200hp, big horsepower means spending big bucks to prevent breakage. Certifiablejeep are you also running headers also? I was looking at either 354 or 373 gears with the one piece axles. Sounds like your set up is what I am going for, I am going to swap in the T-176 for my T-5 . I like a mild cammed V-8 over a I-6, just my preference. Anybody else got AMC 304 they are happy with and have does some great mods.

Brian
Click to expand...

The AMC V8 is a great little engine. The weak spot is the "Front to back top to bottom oiling system". Don't take it past 4500-5000 RPM without modifying the oiling system. Unless you change the cam, there's no point in it anyway.;)
 
Yes, headers on mine as well into glass pack type mufflers... yes the oiling system needs the oil mod as well... forgot to mention that... flow kool water pump as well, K&N filter... hood louvers to keep under hood temps down... lots of little things I guess that makes it all add up.

cb
 
That little AMC 304 wakes up quickly with just a few normal hot rod mods! You would be surprised at how well it will run with a little cam, intake, exhaust and ignition work.

As was stated before, just keep the revs down with the stock oiling system and you'll be fine...

Anybody else got AMC 304 they are happy with and have does some great mods.
Click to expand...
I ran my AMC 304 at the sand drags and scared the hell out of alot of people! :D

Cross drilled, chamferd and knife edged crank, shot peaned rods with arp bolts, oringed and oil galley modified block, forged floating pistons, heads were ported, cced and flow benched (over size valves) (had to notch the block), Lunati cam, FI, and then all the other various AMC go fast stuff!

LOL - most ask why? Why put all that work into a AMC 304 ? Just buy a 360! Well, I wanted to see what the 5 liter could do... Trust me - it did well! And the sound of the eight winding to 7+ was (will be again till I get my 401 built) great!
 
Thanks everyone for sharing your knowledge with me. Is there any modifications you can do to the AMC oiling system such as a better oil pump. I heard the 360 as well as the same problem when you modify the engine. I would like to take my engine up to 6000 rpm once in a while. For the ignition system being stock is the Team Rush approach as good as going for a HEI with an MSD system. I am learning lot's from your guys thanks for sharing your knowledge.

This is new territory for me with regards to engine planning and how I am going to build it.

Thanks Again this is Awesome Place!
 
Canadian CJ 7 said:
Thanks everyone for sharing your knowledge with me. Is there any modifications you can do to the AMC oiling system such as a better oil pump. I heard the 360 as well as the same problem when you modify the engine. I would like to take my engine up to 6000 rpm once in a while. For the ignition system being stock is the Team Rush approach as good as going for a HEI with an MSD system. I am learning lot's from your guys thanks for sharing your knowledge.

This is new territory for me with regards to engine planning and how I am going to build it.

Thanks Again this is Awesome Place!
Click to expand...

The stock camshaft is not going to take you there. As far as "Oiling Mods"
there is a standard method of drill & taping fittings in the intake valley & running a line. Also running aline to equalize the 2 galleys, drill holes in the lower intake valley to speed oil drainback & a deeper oil pan. View attachment 1347

View attachment 1348

View attachment 1349

View attachment 1350

View attachment 1351
 
Thanks LongHorn, for sending me your Oiling Mod Sketches, if you don't mind, I would like to save them for future use if you are ok with that. I guess a machine shop would be able to perform them, by looking at the sketches.
I would be scared to damage something if I tried to do them myself. Thanks again for your help, do you have any advice for ignition system upgrades. Team Rush was mentioned to me. How about the HEI and MSD upgrade is it worth the extra money.
 
Canadian CJ 7 said:
Thanks LongHorn, for sending me your Oiling Mod Sketches, if you don't mind, I would like to save them for future use if you are ok with that. I guess a machine shop would be able to perform them, by looking at the sketches.
I would be scared to damage something if I tried to do them myself. Thanks again for your help, do you have any advice for ignition system upgrades. Team Rush was mentioned to me. How about the HEI and MSD upgrade is it worth the extra money.
Click to expand...

I personally run a HEI now, but I have rum MSD in the past. I was happy with both. I've been told by many others that "Team Rush" works equally well & is cheaper.
 
The drawings were pulled from the net.Someone on the net sells a kit that comes with fittings, instructions & a steel braided line.
 
The bottom valley picture is my engine. The others came off the net. I run that oilpan, but did not have a picture handy. It's a 8 quart "Milodon".
 
If your not going to wind the hell out of the engine much and your timing cover oil pump cavity is in good shape - you can usually get by with a good set of oil pump gears and new oil filter plate with correct mid plates. If your going to rebuild the engine you can increase oil pressure to the galley without putting in the lines by using some small hole cam bearings. Have to be careful about upper end oiling if you do that. Or, get a full timing cover kit if you really want to fix that oiling system...

Oil Link

Oil LInk 2

Oil Link 3

Oil Link 4

Oil Link 5

Oil Link 6

Oil Link 7

Oil Link 8

Oil Link 9

Oil Link 10

Oil Link 11


There is a massive amount of great info at BullTear - AMC ROCKS! Forums
 
Thank-you Very Much Longhorn for your help :)

What an awesome link for Bull Tear, I didn't know such a site existed. I will definitely check them out further for AMC parts.

Brian
 
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