For a 360 project

-
M

MoparFan

Well-Known Member
Joined
Jan 30, 2005
Messages
147
Reaction score
0
Location
Montreal south shore
Hi,

this weekend an idea came back to me, after having talk with MrMopartech. Building a 360 for my 72 Dart.
So here the thing, I have call a guy that has a 360, sitting in a dry garage for 3 years. The engine is out of a 74 (Monaco not sure), was running good and claim he has 60000 miles. 100% stock never been opened. He claim the engine has the "big head" and 275hp ... but has a 2 bbl carb :!: I think I can have it for 400$
The other 360 I know of is sitting in a car in a junkyard, for I don't know how many years, and the guy was asking 200$ for it. Th car looks like a mid-late 70's, maybe a Fury.

So you would go for wich one?
The plan is to build this slowly (2 years plan)...but at least to build one. It would my first attemp at this.

So here is the plan till now, building something not bullet proof but with some guts:
- Around 10.0:1 compression
- Keith Black KB107 piston 0.030 over
- Hedman headers 1-5/8 primaries, with a dual 2-1/2" exhaust
- A cam that will have the engine running mean (not too smooth)

I don't much stuff yet, but these 2 i have and I want to use it:
- Holley Street Dominator single plane intake
- Thermoquad Carb 750cfm

What type of ring to use?
Do I only need to have the cylinder punch 0.030 over, or do I have to have the bottom worked also?
Do I have to have the deck milled?
The head? How wuch is worth a valve job (seats and 3 angles valve job)?

Anyone know a diy rebuild part list?
 
All 360's until the late 80's had the same head so there is no "big head". Since you are just looking for a core to rebuild there is no advantage to paying $400, even $200 for the junk yard motor is a little high. I picked up a 360 that came with an after market single plane intake for $50.

Take a look at this link. It chronicles my 360 build. http://www.forabodiesonly.com/mopar/showthread.php?t=4798

Here is a claculator to help you figure compression http://www.csgnetwork.com/compcalc.html

BTW, with the heads on the engine and the KB107 pistons you will have to have the block zero decked to get to 10:1 compression. Also, the KB107 pistons come in 0.020 over so if you don't need 0.030 go with the 0.020.
 
Thanks a lot, I guess I did not search enough, cuz your built is what I had in mind.
So i have done some homework:
- 360 engine: I will have to look further to find something at max 100$
- Would you use Moly or Plasma-Moly ring
- Head gasket? Mopar Performance = good?

I have tried your link for the compression ratio. Using KB107 piston, a 80cc combustion chamber, 0.05 clearance to deck, head gasket 4.06 bore and 0.028 thick = 9.1:1...seems not too bad to me (maybe i'm wrong also :newb: ).
But how big is the combustion chamber on 360's head?
 
The combustion chamber on open chamber small block heads is ususally in the 68-72 cc range. The only way to know for sure is to measure which is quite simple. Get a piece of plexi glass that is big enough to cover the chamber, put a small hole in it positioned so it's near the edge of the chamber. Go to the local pharmacy and buy a plastic syringe that is graduated in cc (try and get one up around 100 cc). Now put some grease on the edges of the plexi glass to seal it to the head. Now carefully fill the chamber with a liquid of your choice and measure how many cc's it takes to fill. Do both ends of the head and take the average.

Also, most composite head gaskets have a compressed thickness of ~0.040". An the bore of the gasket is much larger than the bore. For example a Fel-Pro gasket has a bore of 4.150".

BTW, a KB107 piston will not be down in the hole the 0.05 you mentioned unless the the block was way off and the stock pistons are close to 0.1 down. I think you will find the the KB107's will be more like 0.01 to 0.02.

A quick primer on rings. All rings are made of cast iron or ductile cast iron, ductile cast iron is more durable. Rings then come with with either no coating on the wear surface (that's what came in your engine), chrome face (not used much any more) or moly. Plasma moly is a different process for apply the moly coating that is supposed to be more durable and less likely to flake off. The coatings are typically only on the top ring but you may see it on the second ring and it's there to reduce wear.

When I did my engine I got a lit from Mancini. It included a complete Fel-Pro gasket set, Clevite bearings and Speed-Pro moly rings. I had them substitute the kit pistons for the KB107's which added less than $100 if I recall.
 
I,m a little lazy, I got a short block from Chrysler for $1100.00, with 9.5 compression and is .30 over. You can still use your intake and carb. Just need some good heads.
 
I went both routes. Create short block and rebuilt a 360. The create hi-comp ratio had a small problem. (Sarcasim) the drivers side of the block was deck to much and had positive pistons while the passenger side did not.

I did a KB-107 @ .030 that ended up being zero deck without machining. You should only overbore if you have to. Thicker wall are stronger wall which equals straighter cylinder wall. That means more HP and longer life.

When you do your head, the 3 angle valve job should be done if you need new valves. Otherwise, do not do work thats not needed. It'll not only save you some bucks, but it will get you up and running faster. The amount of power gained is small. Worth it? Yes. But it's not a big thing. When you get to the point of porting your heads for more power, then go the full route and go all the way.

dgc333 gives good advice.
 
I have a 360 in a 72-73 satelite station wagon i just bought if you're interrested???Just let me know.I don't know if it runs or not but it appears to be complete except for carb and intake.
 
rumblefish360 said:
You should only overbore if you have to.
Click to expand...
How do you know if you have to overbored the cylinder. Is it the machine shop that will tell me?

fstbackfish said:
I have a 360 in a 72-73 satelite station wagon i just bought if you're interrested???
Click to expand...
Thanks for the offer, but from what I see you are in Colorado, wich is quite far from where I am. But maybe someone else here closer to you, could use it.
 
So far it seems like everyone here is giving great advice, I have just had a stroker 360/408 built and my only advice is to use a commetics gasket they cost more but will not blow out like my Felpro race ones did they are about $200 but worth every penny, you will have to noth head for clearence, there worth it Cheers and good luck
 
HA, this is how my project started. Do a simple performance rebuild on a junkyard 360 and slap it into the car for a fun driver and racer. Well that idea was lost about five thousand dollars ago. Good luck!

It'll start simple but you'll start figuring out what best then better combo's look like all based off your original idea. Only thing I can say is keep talking about your set up to anybody who knows anything and dont take any short cuts.


little preview of my combo:
10.5:1 kb's in a 360, full ballance, 509 lift purple shaft cam, 1.5 CAT roller rockers, aluminum edel rpm heads, air gap intake, 650 double pumper,full msd set up (distributer, 6al, coil, timing control), headman headders
plus a 904 manual valve body, 3000 stall, hurst pro matic shifter, 410's in a 8 3/4 with moser axles, mini tubed, subframes...

yep that all started as a simple junkyard toss in and drive away.

oh yeah its been three years and its still not running.
 
I have a 76 360 that came out of my friends mothers car. I freshened it up with a new cam (slightly up from stock) lifters,timing gears&chain,oil pump,rear main seal,freeze outs,edelbrock performer intake and painted 65 smallblock red cause it was going in my 65 Valiant. You can come and get it for 850. US I'm in NY. Drop it in and go. Oh, I forgot to mention, i put 340 j heads on it also.
 
MoparFan said:
How do you know if you have to overbored the cylinder. Is it the machine shop that will tell me?
Click to expand...
Yes, they'll tell you. This is something they will not due unless it's needed.
 
man i love them 360's, if you like sleepers, i just recently sold my 1987 5th avenue sleeper. stock 360 short blk, mp 4-bbl stock cam, 1.88 valve heads, edlebrock perf intake port matched, thermoquad carb, 1 5/8 hedman hedders, 2 1/4 exhaust, dynomax turbos, no cats, 999 t/flite with a 2.74 low gear, 8 1/4 w/ 2.94 sure grip, car wt 4100 lbs, consitent 14.80 car. complete with leather, cruise, air, power every thing, 16mpg great every day driver! fun car i miss it! the local kids didn't know what hit them! they would all laugh about mt dash mounted tach.
 
You must log in or register to reply here.
-

Back
Top