318 screamer

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Valiant50

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ok here is the lowdown
I am in South Africa - so junk the 318 talk is not welcome - having a smaalblock over here is great ,having two is hogheaven
I do have the following
1 x 1978 318
1 x edelbrock torker 340/360
1x edelbrock performerplus cam
1x carter avs of a 68 340
access to a selection of performance smallblock heads
2 x 360 centerdump exhaustmanifolds
and a RSA Valiant Charger think 1970duster tail and 1970 dart nose
oh yes a tf904 la
Is this combo viable with the correct heads? ie 360 or 340 ones
 
Valiant50 said:
ok here is the lowdown
I am in South Africa - so junk the 318 talk is not welcome - having a smaalblock over here is great ,having two is hogheaven
I do have the following
1 x 1978 318
1 x edelbrock torker 340/360
1x edelbrock performerplus cam
1x carter avs of a 68 340
access to a selection of performance smallblock heads
2 x 360 centerdump exhaustmanifolds
and a RSA Valiant Charger think 1970duster tail and 1970 dart nose
oh yes a tf904 la
Is this combo viable with the correct heads? ie 360 or 340 ones
Click to expand...

I love my 318. Its not perfect but it goes great.

I have what I believe is a 76 or 78 318 block......J heads......a 650 edelbrock carb, edelbrock performer manifold, dougs headers...727 tranny w/ 2400 stall.....

Wish I had more low end, but that is the purple cam thats in it....LOTS of top end.
 
I'd say no right off the bat due to the cam. It is a lame grind with the given insult of "A broom stick of a cam."

Answer me/us this.

What is the intended plan for the 318?

What is the compresion ratio
rear end ratio
is a torque converter change out OK, within the budget

Alot of what you answer can hjelp paint a picture of where you want to go and do with this set up. Then, I can point to a set of heads for you.

Generaly speaking, I like 318 heads on a 318 unless your really trying to wack out some HP. Opening up the ports to a 340/360 size is a big help in creating a really nice intake track.
 
Smaller port (318 ) heads will support 300-325 HP pretty well assuming 360 valves have been fitted and basic porting work is done. At power output beyond that the larger port (340/360) heads are needed for airflow. As you indicate the use of center dump exhaust manifolds, we can assume that you will not be producing more than 300 HP. They really don't flow very well.

Compression is a major obstacle in getting power out of a 318. The stock pistons in that engine might yield 8:1 if you're lucky. And that's with 318 heads. With 340/360 heads, which have a larger combustion chamber, compression will be much closer to 7:1. There are two common solutions to this problem. First would be to skim the heads to increase compression. A substantial amount of material would have to be removed which is costly and custom shorter pushrods would be required. The second alternative would be to fit higher compression pistons. The Kieth Black KB167 will get you over 9:1 with the 318 heads, and there have historically been 11:1 domed pistons available for the 318 which produce about 10:1 with unaltered 340/360 heads. Domed pistons with large chambers is certainly an "old school" way of raising compression and less than optimal. But it will work.

Not knowing what the quality of petrol is in SA It is difficult to make a recommendation regarding compression ratio. Furthermore, not knowing compression ratio it is difficult to make a cam choice. The cam you list will work OK with low compression, but the end result will hardly be a screamer. And you'll be lucky to see 300 HP. There are better intake manifolds out there also, the Torker would be a bad choice for that cam.
 
We are quite lucky with good quality fuel with a 95 RON being available everywhere
CR in the 9.5 to 9.8 range..this is africa afterall so I must Future proof
so a more radical cam is not a problem - something out of the Lunati Voodoo Stable maybe?
8 3/4 742 currently 2.76, but have 2.9x and 3.23 ratios available.
Idea is to build a nice street performance car small block not upsetting the handling,
with lots of grunt
Oh yes 340 hp exhaust manifolds is also available
Reason for manifolds? RHD - we have no space - oilfilters are relocated to clear space for the steering box
A friend indicated that he might have a stroker kit for the 318.....
 
That 95 RON gas equates to about 90-91 (AKI) octane in US terms. We have the same over here as our regular unleaded.
 
it might break into the high 15 second zone. idk what you consider a screamer but if thats it good luck!
 
AbodyJohn88 said:
it might break into the high 15 second zone. idk what you consider a screamer but if thats it good luck!
Click to expand...
come on guy he's in africa !how many hot rods do you think they can get a hold of?for there it probaly is screaming:banghead:
 
ok up date time
Due to capacity limitation the torker is being sidelined(willfind a use for it), rpm airgap,plus a set of 302 heads matched for said manifold plus some 340 hp exmanifolds..
starting to sound better?
 
The air gap ports are way bigger then the 302 ports can ever be without ruining the flow of the heads..... soooo, in the end the performer or small port single plane manifold would be a better choice running small port heads.

I gots lots to say, I'll be back later.

And Rumble is right, the EB cam is a junker.
 
Your biggest problem is exhaust; being a right hand drive vehicle, nothing I know of, US made, in the line of headers is gonna work. You might try the UK, or Australia for sources of headers designed to fit RHD vehicle. Myself, I'd start looking in OZ.

In stock form a 318 suffers from the 3 C's ; compression, carburation, camshaft. You stated that you have around 9.5/9.8 CR; that's a great drive it anywhere/anytime CR, it's almost 1 point above stock here in the US. The AVS is ok (the last "teen" I built had a 750 Holley DP), it's what you have, so go with it. Go up on camshaft a little, it may be old school, but a MP Performance 280/.474 cam would work very well; new school "Voodo", or "Xtreame Energy" would also work quite nicely. If you can get one, go with an Edelbrock Performer; Air-Gaps are nice but cost more; it sounds like you don't have a lot of cylinder head choices; 302's with 1.88/1.6 valves with light bowl work, would make a nice easy build combination; 2.02 valves if you have more money to spend. (a friend went 12.7* sec in the quater with a 318 toped with home ported 302's with 2.02 /1.6 valvesin a 66 Barracuda) 340/360 heads offer more port window for power, but will drop compression way down; 1.5 to 2 points unless you cut them severely.

3.23 gears are ok, 3.55's if you can get them will be much better. I would not go deeper than 3.55's for every day driving. Gears are tire and converter dependent.

Hope this helps, and good luck!
 
You can get headers out of Aussie to suit RHD A bodies. Pacemaker are really good. They even clear a power steering box. (But boy they are a tight fit. Just make sure that you get ones with the correct header flanges.
 
302 heads ported out to 340/360 port window size. Thumbs up!
 
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