318 combo

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318Goon

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Hi All,

You may have seen my 'goon in the welcome thread. I want to liven it up a bit. Currently it's got a bog stock bottom end with a warm cam (no specs, sorry but lumpy at idle), dual propane throttle bodies (slightly over-carbed) and slighty ported open-chamber stock heads. Running a 904 with a 2800 stall (which I don't mind ditching for a stock converter).

I've had some top-end issues and I believe I've got some top-end issues. Since I bought it it's been a bit clackity clack up top but it's developed quite an ominous (and loud) clacking now. The propane setup is a bit of a pain to remove (to get to the valve covers), so i thought while I'm at it I should have a better look at my combo.

It's probably time for a new cam/lifter set anyway, so I thought I might tame the cam a little bit to get some more low-down torque.

Something around 445/450 lift, 212@50 - something like the the Comp 260H cam.

I'm planning on building a better bottom end in the future, so I'd like whatever I get now to hopefully suit what I build later.

My current bottom end is bog-stock, so probably low 8s compression. I plan to build a 9.8:1 bottom end with KB 167 hypers in the future, but to be realistic it's probably at least 6-12 months down the track if not more.

So (yes, I'm long-winded) I've been thinking about buying a pair of Indy LA-X heads, 62-64cc closed chamber with 1.60/1.88 valves. I'm thinking that the smaller closed chamber should hopefully wake the engine up a bit by bumping up the compression a touch, and the increased flow should help with the over-carbed aspect.

The only thing I'm concerned about is that the valves might be too large, and might kill low-down torque - which is what I'm after.

Any thoughts?
 
If you're looking at aftermarket cylinder heads my first choice for your build would be the EngineQuest Magnum heads. They are intended as new factory replacement heads but feature improved ports and extra metal in key areas for strength. Only $900 a PAIR assembled from Competition Products. They have LA-style intake manifold bolt pattern but require Magnum pedestal rockers, which would probably be an upgrade for you with the 1.6:1 factory ratio over 1.5 (actually less) of stock LA's. These heads are also known for lots of low-lift flow which is what builds torque esp. on the bottom end.
 
Is run a split cam with a s a little more intake duration. (218 @ .050) which will still work with the stock OE stall converter. Gears not lower than 3.21/3.23 on a stock tire. A 110 centerline as well.
 
Running Propane with low compression and a rumpity-rump cam, i'm not surprised it's soft on the bottom end. Bet you need to run a lot of timing to get her going.

I can't really recommend a combo, since I really don't know how much your propane can take. Meaning what octane rating and if there's a certain amount of butane mix. Trying to keep the cylinder pressure up may call for talking to someone familiar with that type fuel on the camshaft choice.

Good Luck & i'll be watching :thumleft:.
 
I bought a set of the EQ heads,same place. Nice heads. The Howard's came,listed in post 6,would work VERY well.With the EQ heads,and your expectations. Rubber everywhere.
 
Thanks for the replies. To answer a few questions, I'm running 2.92 gears, and propane in Australia is around the 100-102 RON mark octane-wise.

The EQ heads do look interesting. I like that you can still use LA-style intakes on them as well. Is there much to be changed valve-train wise? If I do decide to go for the EQ heads do you think it would be worth going for roller-rockers if I have to change the rockers anyway?

I'm wondering, in terms of 'bang for buck' if the changes required for the EQ heads, versus the LA-X heads would be worth it?
 
Used to work,at a Mopar head shop. The EQ's are a 172 c.c. intake casting,x'es 179. My ex boss(head porter) ,had to a LOT of clean up(R. Got [email protected] ,with 1.97/1.62 castings. He hated the castings,out of box.With what,you want to do E.Q's fit better. You need 5.2/5.9 Magnum rockers,matching hardware. Will need AMC V/8 lifters,oil through ,Chevy style push rods.Gives you an idea..H.S.)
 
the more I read about the eq heads the more I like them. from what I've read on the hughes website it seems that if you use standard rockers with a flat tappet cam you need to machine the pushrod tunnels, but if you use a roller cam you don't. if that's right then would it make sense to spend the money on rollers rather than machining?
 
318Goon said:
the more I read about the eq heads the more I like them. from what I've read on the hughes website it seems that if you use standard rockers with a flat tappet cam you need to machine the pushrod tunnels, but if you use a roller cam you don't. if that's right then would it make sense to spend the money on rollers rather than machining?
Click to expand...

I haven't found this to be true with factory Magnum heads using a .454/.475" lift flat-tappet cam, although the pushrods did come very close to touching the holes in the heads. If anything you might just need to clearance them with a hand grinder. I'd mock it all up first to see if machining is necessary. And even if it is it should be way cheaper than converting to roller lifters which is several hundred dollars at the very least (probably more for you since you're on the opposite side of the world lol)

Like Abodybomber said you need AMC-style lifters with oiling holes, hollow pushrods, and Magnum rockers+hardware. Really not much, altogether maybe $300 unless you upgrade to roller rockers which would be about double or more.
 
Thanks - you guys are awesome. I've been asking for quotes for the EQ heads. Competition Products are out of stock. Hughes quoted me $795 for the heads (assembled) and $599 for shipping (ouch!)

Rogers Performance quoted me $572.50 for the heads (bare) and $142 for shipping! Thought that was a pretty good price, just wondering if anyone has any experience with Rogers - I couldn't find much information on them.
 
Not sure yet - I'm checking out some other shipping options at the moment. I've also asked Rogers for a quote on assembled heads so I'll see how that comes up.

I really like the look of the Howards cam recommended by moturbopar. Short duration, reasonable lift.
 
Aren't Engine Quest heads made in Queensland? I don't think paying to have them sent overseas twice would be very economical. You've got an advantage, there. You may want to check some local suppliers to see if you can get them direct.

My friend up in Golden, Colorado purchased some of them for an LA 360 for about $850. What he ran into was an issue with coil bind on his cam, with the 1.6 rockers and his cam. I'll have to get the cam specs. He ended up running beehive springs.

If you run LA valves, the Magnum valves and retainer locks have a different groove height, so you need to get those measurements and parts to fit. He ended up using Magnum valves with magnum style locks that he spent a bunch of dollars on at a dealer and told me that if he had to do it again, he'd go with an LA style valve lock and groove valve.
 
DaveBonds said:
Aren't Engine Quest heads made in Queensland? I don't think paying to have them sent overseas twice would be very economical. You've got an advantage, there. You may want to check some local suppliers to see if you can get them direct.

My friend up in Golden, Colorado purchased some of them for an LA 360 for about $850. What he ran into was an issue with coil bind on his cam, with the 1.6 rockers and his cam. I'll have to get the cam specs. He ended up running beehive springs.

If you run LA valves, the Magnum valves and retainer locks have a different groove height, so you need to get those measurements and parts to fit. He ended up using Magnum valves with magnum style locks that he spent a bunch of dollars on at a dealer and told me that if he had to do it again, he'd go with an LA style valve lock and groove valve.
Click to expand...

Doesn't coil bind have more to do with the springs? I'm pretty sure the Hughes springs I have on my stock Magnum heads are good up to .650" lift, well over the guide-to-retainer clearance.
 
The EQ heads used to be made in Toowoomba, Queensland. Unfortunately the foundry that made them closed last year. I've checked with local suppliers and it seems that I can only get them from the US. Bummer, hey.

In terms of valves, I'd prefer to buy assembled heads - which would presumably be fitted with magnum valves. Buying bare heads and then trying to source correct parts I think would be more trouble than its worth.

Any cam I choose will be under .500 lift so hopefully I won't have any issues with springs.
 
Man, that sucks about the foundry!

Yeah, I'll have to ask Jerry what he did, K. He told me that there was some issue with coil bind because of the springs he had. I'll get the information from him on what he is running and why he had to go with beehive springs.

Anything under .5 lift should be fine with practically any spring and typical retainer.
 
To resurrect this, I've decided to go with the EQ heads, but I'm trying to figure out rockers, etc.

I figured I might as well change the cam and lifters while I'm doing the heads, so I'll grab the Howard's cam & lifters suggested above. I'm not sure about which rockers and pushrods to use. My block is stock height - is there an aftermarket pushrod that I can get or will I need to measure it once assembled? As for rockers, is there a cheap 1.6 option that anyone can suggest?
 
Factory Magnum rockers are out there.

BTW, my friend said the reason he's running beehive springs was because of the lift on his cam. He purchased a cam for the 1.5 total lift numbers and ended up having to adjust his build, because he spaced the 1.6 magnum ratio.

I have not heard good things about the Comp lifters. Anything made from extruded aluminum is a bad plan. they lose adjustment quite quickly.

Check into Hughes Engines. Someone else may chime in with a more affordable rocker setup that is good quality.

There is a pushrod that is to length for an LA to Magnum head, but the best route is to measure. Hughes has an adjustable rod to measure as well.
 
Propane motors love compression and timing. I see it a ton in the off road world because it allows the motor to run a funny angles. Its considered the poor mans fuel injection. 13:1 compression is nothing unusual if propane is your fuel of choice.

Its easy to run a turbo on propane too. Just plumb it in as a blow through carb, connect a line to the intake manifold for a boost pressure to the back of the mixer and ta-da, you are now boost referencing the fuel pressure.

The only issue of running propane is you have to have good vacuums to get it to start up. High compression and the big cams, don't lend them selves to that.
 
The question is, do you have a grand to spend for heads? A little pricey there. Maybe you can find some decent ones local for a fraction of that.
 
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