360-2.02 valves Fit a 318 block with no clearance issues?

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emnestor

emnestor

emnestor
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I have a nicely worked set of 360 heads with 2.02 valves lying around and thought I would install them on my trucks 318. I am having the 318 rebuilt and thought I could save some money by not having to have the heads done. So I am only doing this swap to save some bucks. The 318 is a 1987 block and it only has the "RV" style cam. No big lift here, pretty much bare bones stock. Just want to know if the big valves will clear the cyclinder bore?

Also what are your thoughts on the compression drop this will cause vs the better flowing benefits of these worked heads. This is just a daily driver.
 
The valves will fit fine. Two things to consider, first the mild "RV" cam will seem a little less mild with the big valves. Not a big problem for a mild cam, but something to consider when swapping onto an engine with a more aggressive profile. Second, and more importantly, 360 heads have larger chambers, and your compression ratio will take a dive if you bolt them on as-is. Easiest solution is to have the heads milled at a machine shop to reduce chamber volume. Make sure to have the intake face milled as well, and order shorter pushrods.
 
I think I would use the stock 318 heads with some quick bowl blending and cut back valves. The lower CR will hurt more than the gain in flow.
 
Well, the idea here was to save some money and not have to work the 318 heads. This is just for a daily driver
 
You could use the heads and add compression with new pistons, since your rebuilding the bottom end. Then you'll have a pretty stout 318, that's what I would do.
 
1987 318 should have the small chamber swirl port heads. This is a photo of a 85 318. I would think the 360 heads would lower the CR a good bit.Maybe cc them to see the difference.
 

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Yes! While rebuilding the 318, use something like the Keith Black Hyper pistons.
The KB-167 (someone correct me if I'm wrong)
They are a flat top piston with generous valve reliefs for such builds. You can mill the blocks deck to get these slugs at a zero deck height and use the 360 heads with excellent success.

This is a really good route to take for the 318! You will not be disappointed.
 
Does this sound like a good combo? Got the motor with the car so I haven't run it yet. I do want to put it on a run stand to break in the cam and make sure the rear seal isn't a leaker. Just curious what you folks think about the build. Has a 600 AVS and stock exhaust.


The engine is a stock 318 out of a 1987 Aspen, Therefore thecrank and rods are stock cast items. The pistons are TRW .030 over. I had themachine work done at a shop in Pensacola. I think I gave you the receiptdetailing what he did – please check your paperwork!.



The heads are unported 360 units. I did port the exhaustmanifolds to match. The intake is an Aluminum Edelbrock unit and has not beenported. The heads were given a three angle valve job and had new guides andseals installed. I did the final assemble and I degreed in the cam andinstalled new bearings, rod and main, a new rear main seal, new timing chain, newoil pump and all new gaskets.



Please be sure to prime the engine before attempting to start!!!And thanks for keeping me updated.
This is the cam spec.
[ame]http://www.jegs.com/InstallationInstructions/300/350/350-2177.pdf[/ame]
 
cc the heads and see the difference.

I ran a 318 with 10.5 pistons and 318 heads. Too much compression and it would overheat over 80° outside. I swapped a set of 360 heads with 6 more cc's and the compression was down to 9.2 and I was able to run cheap gas in it. That was with old 70's vintage parts, I'm not sure what your 80's vintage parts will do. Measure them and see.

My point is that for $300 set of 10.5 pistons may be able to allow you to use the larger port head with a 2.02" intake valve in it.

Or you could put the 2.02" valves in the 318 head and open up the ports a bit.
 
Just my opinion, but you should stay with the 318 heads.........as a daily driver, you would be disappointed because of the lower compression, bigger ports and 2.02" valves.

A 600 carb, RV cam and only 318 cubic inches just doesn't "match" the bigger heads.
 
That sounds like a good option. I guess I will open the motor up and see if she needs new pistons, probably does, and go with the KB Flat Tops and 360 heads.
 
I made the mistake of putting a set of 360 J heads on a bone stock 318 rebuild (other than a mild cam, eddy intake and carb) once. Had it in a mud truck - had a helluva lot of torque but would not rev up to save it's life! Fixed that after a couple years and put a set of bone stock 318 heads on it! Still runs great to this day!!!!!!
 
I would go the KB 167 route but saying that my first truck 76 2 wheel drive 318, I swap 360 heads 4 bbl intake 340 cam on stock exhaust and she was definitely faster than what I started with, and around the same time my cousin put his dads 340 duster back on the road with a stock 318 short block ported T/A heads, LD340, some cam his dad had laying around pretty lumpy, rusty old headers that were on the car and 3.91:1 out back it was definitely fast, I know compression is important but do we go a little overboard sometimes about it?
 
273 said:
I know compression is important but do we go a little overboard sometimes about it?
Click to expand...

It's not so much that we go overboard about compressions role in performance, but there are probably dozens of folks that have dropped large chamber heads with sunken valves on an already low compression 318, cam it up with something fit for an engine with 2-3 points higher CR, then wonder why it runs like garbage.

Can 360 heads be used on a streeter 318? Absolutely. Should you match other components to suit the likely lowered compression ratio-without a doubt!
 
Everyone says 360 heads are too big in the chambers, but I think most of this is people reciting what they've read.

For me, a stock never shaved 318 with 1.78/1.5 valves was 66.5cc.
My 360 heads, unknown history Ferrea 5000 2.02/1.6 valves are 66.5cc

And yes the 2.02 valves fit with no necessary clearancing done to the top of the bore.
 
Txstang84 what I was trying to get at is a stock 318 is probably 8.5:1 CR at best and a half a point up to 9:1 or down to 8:1 is only gonna be plus or minus 5HP at best as long as the cam is kept with in reason everything should be find but thats the problem people just want large cams. I know a lot of people dispute magazine HP numers but for 318 guys I like to quote engine masters hop up of a stock long block with headers, 4bbl and a comp xe262h cam made 282 HP which is a pretty cheap bump after that hp only gonna go up in small increments and cost is gonna go up in large increments :)
 
273,that's a excellent statement. Real operating torque(2000-5000) essential here.
 
emnestor said:
I have a nicely worked set of 360 heads with 2.02 valves lying around and thought I would install them on my trucks 318. I am having the 318 rebuilt and thought I could save some money by not having to have the heads done. So I am only doing this swap to save some bucks. The 318 is a 1987 block and it only has the "RV" style cam. No big lift here, pretty much bare bones stock. Just want to know if the big valves will clear the cyclinder bore?

Also what are your thoughts on the compression drop this will cause vs the better flowing benefits of these worked heads. This is just a daily driver.
Click to expand...

You have to notch the cylinders where the walves turn. They don´t fit the small bore size..
 
emnestor said:
I have a nicely worked set of 360 heads with 2.02 valves lying around and thought I would install them on my trucks 318. I am having the 318 rebuilt and thought I could save some money by not having to have the heads done. So I am only doing this swap to save some bucks. The 318 is a 1987 block and it only has the "RV" style cam. No big lift here, pretty much bare bones stock. Just want to know if the big valves will clear the cyclinder bore?

Also what are your thoughts on the compression drop this will cause vs the better flowing benefits of these worked heads. This is just a daily driver.
Click to expand...

No valve clearance issues!
Perfect combo for a blower!!
 
Valle6062 says that the cylinders will have to be notched. many of you said it would be fine. Which way are we leaning here?
 
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