possible 318 build

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74scamp360

74scamp360

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well guys it would seem my project is taking another turn. many of you have probably seen or read my thread about doing over my 360 for my 74 scamp. Well the "tight" budget that i was talking about before is now all but non existent. Since the 360 needs pistons at minimum i've decided that its just not going to be possible to rebuild my 360 and have the car on the road by the spring, i just don't have the money. Now i have a complete 318, not siezed and from what i've seen so far in pretty good shape, the new idea is to pull it apart and do a nice rebuild on it, rings and bearings, things like that and maybe put a little bit of a cam in it and use the holley strip dominator intake i have. Problem is i would like to put a bit of a cam in it, nothing major at all just to help it out a little. I don't want to get into changing out valves springs, lifters, rockers stuff like that, i just can't afford it right now, i'd just like to slide in a bit of a cam and get this damn car back on the road. So, suggestions?? heads will be stock smogger heads, 596's at best. Headers if i can afford it and the strip dominator intake and everything else will be stock including the pistons. So let me know what you guys think.... again. is it really possible to put a decent cam in it without having to replace springs, lifters, rockers etc. Your help is very much appretiated!!
 
The first thing I would check is the bore size and make sure it to doesn't need pistons. If that is so then they would cost roughly the same amount to build with completely different amounts of power.
 
nope it doesn't need them, its still all in one piece, its just its been sitting without an intake on it outside so thats why i'm pulling it apart
 
Sounds more like your shooting yourself in the foot at the expens of doing it right.

Stock compresion, with a strip Dom and a sizeable cam without a valve spring change.

This equals a waste of money, time and it will add up to a go slow MoPar.
 
rumblefish360 said:
Sounds more like your shooting yourself in the foot at the expens of doing it right.

Stock compresion, with a strip Dom and a sizeable cam without a valve spring change.

This equals a waste of money, time and it will add up to a go slow MoPar.
Click to expand...

okay, well thats why i asked right, i already have the strip dominator, it was given to me as a gift so no wasted money there but i see where you're coming from with the cam. Its not going to be fast, just needs to run again. Unfortunately i'm a young guy with little money, its looking like do it this way or watch it sit. If i were able to learn how to do some minor porting and polishing do you think this motor would benifit from putting on 596's (i know still smoggers but its the best i got) with a minor port/polish? If you don't think its worth my effort let me know but i would be nice to do as much for this 318 as i can. opinions are appretiated. Thanks
 
NO! alow comprsion 318 could use a cam no larger than 224 (or so) @ .050 and you NEED TO GET THE NEW MATCHED VALVE SPRINGS!

The strip Dom needs to be put to the side and use ethier a OE 4bbl or a performer. Weiands action plus is also good.

Porting a 360 head will kill it all. A single plane will kill it, a big cam will kill it.,etc....
 
If the shortblock and 596 heads are actually in decent shape use them, I've thrown together similar stuff and it has ran fine.

The key to making it work is a 3.91-4.30 gear and higher stall converter, you don't need a $800 PTC 9.5" for this setup, a daaco 2500 stall will work fine, they're available from most supply houses.

For a cam I would run something small like the large summit cam or the MP 268/272 and get a set of $80 comp springs, the stock rockers will work as long as they're not worn out, you will need headers and a 600-650cfm carb and you will need to re-curve a stock dist so you have 15-20* at idle, 36-38* total.

You need to check the engine over really good while it's apart, make sure the bores don't have a bunch of taper and that the valves are sealing, you don't want what little compression it has going past the rings or out the exhaust port. I put one of these together for my old Duster and everyone that's seen it run or ridden in it thinks its a 340 or 360, I ran some 8.60's in the 1/8 in driver trim on regular radials.
 
If your goal is to just get the car running and on the road you would be much better off using the stock 318 heads and trading your 360 heads and intake for a performance 318 intake and some headers. Your 596 heads have larger ports, valves and most importantly combustion chambers than the 318 heads. You will drop the already low compression ratio of the 318 down to an unacceptable level. A larger cam, the big ports of your intake and the larger ports/valves of the 596s will flow more air/fuel than the stock 318 pieces but the drop in compression will kill any benefit derived from the improved flow. You will loose what low end power you had and would need a taller gear and converter to spin the motor up to get it into a useable power band. You can mill the heads and/or use thin head gaskets to get some of the compression back but then other issues (more $$) can crop up. You need to optimize what parts you have on hand with your available funds to put together a combination that you can live with while saving up to get the motor you really want.
 
ok, thanks guys you've made some great points. i'll see what i can come up with for a used intake that will be better suited for the engine. i wasn't sure about the heads, thats why i asked, sounds like leaving the 318 ones on is a far better idea for compression purposes. like rapom65 said i just need to put something together so i can run this car while i try to save up for the 360 i had talked about building earlier. Thanks again guys, this being my first build i still have tons of learning to do.
 
oh i forgot i have the stock intake on my 360 duh lol. would that be a better suited intake for this 318? or should i be looking for something off a 318 originally?
 
The oe 360 intake will be fine up top the 318.
 
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