Alloy Cylinder Head Or Not

[WJM]

Hi All. Sorry I have not been around for a while but do try to keep up with posts. I see in USA there is a person selling alloy cylinder heads (on ebay) for the MGB. They are expensive and just trying to get some info on them before I think of buying one. Are they better than the old cast head. do they give any better performance or do they have any advantage. I look foward to your fors an against. Thanks John

 

[aeronca65t]

John:
You can actually buy them from Moss Motors (a big USA / UK supplier).
I do not have one on my car. But as I have heard it, they are lighter than the iron head (of course), but do not actually flow any better.
So, a lot of money for precious little actual horsepower gain (if any).
Perhaps others will chime in here, but that's what I've heard from my fellow vintage-racers.

 

[billspohn]

Fuggedaboutit.

Money tossed away to no good end. If you can't find a decent cast iron head I suppose they are an alternative. You won't notice any difference in performance (the weight change is nowhere near large enough to be noticeable).

The weight change wrought on your wallet, on the other hand, will be significant!

 

[Steve_S]

I spoke to Sean Brown about this once. He feels the only aluminum head worth going to is a cross-flow, and only after significant modification to improve it's air flow. Big $$$. You can certainly save weight by using one, but don't expect much of a performance boost from the engine. I suppose it will also shed heat better which keeps the engine cooler and allows you to run higher compression.

 

[billspohn]

I spoke to Sean Brown about this once. He feels the only aluminum head worth going to is a cross-flow, and only after significant modification to improve it's air flow.

Ask Sean when and where that promised article on the mods he does to the stock MSX head will be coming out!

 

[Tosh]

FWIW;

During the Friday AM tech session (it was a discussion about how to increase power) at NAMGBR '08 someone asked (or he may have mentioned it in passing) John Twist what he thought about aftermarket aluminum heads. As I recall the gist of his reply was this;

"By itself, a lot of money for no real power advantage".

He was very positive about the stock heads, warts and all!

Keep on.

 

[aeronca65t]

Yeah, Tosh. That's basically what he said. (I was at that tech session too).

 

[DrEntropy]

if ya contour a stock head, fix th' ports to match in and out and then CC it, th' result will be obvious. At idle and WOT. Well worth the effort.

 

[WJM]

Hi Thank you all for your advice. I will stick with my original head. I have had the car now for about 6 years and hope to this year to do a restore on her. The engine is running fine but will do a complte rebuild while I have it out. I have also picked up a overdrive box for it and will fit it at the same time. Does any one know if I have to do anything to fit the new gear box or will it go straight on. My car is a 72B will the wiring be there for it or will I have to run new wire. Thank you all again for your remarks on the alloy head and saving me money. Kind Regards John

 

[RonMacPherson]

Before you "diss" the aluminum head, I recommend you check out the Pierce Manifolds web site. They're in California and I know he sells a lot of stuff to Moss...

 

[PAUL161]

if ya contour a stock head, fix th' ports to match in and out and then CC it, th' result will be obvious. At idle and WOT. Well worth the effort.

Doc, if your going that route, wouldn't it be advisable to blueprint and balance also, figuring porting and relieving is a little costly,if done right, might as well go all the way. When we used to run sportsman class,(do anything to the engine you can't see), circle track, balancing the engine was more important than anything else.

 

[DrEntropy]

Certainly so, Paul. Balancing is of great benefit too. But I kinda 'assumed' it was only getting a head R&R.

 

[PAUL161]

Ah yes, I see whacha mean.

 

[Hap Waldrop]

The alloy head, has ports not nearly good as the stock cast iron head, the intake port on the alloy head has a guide boss protruding into port, the cast iron MGB head does not, of course all this can be corrected if the head is ported, but out of the box the alloy head flows less than the cast iron head, and it's intake port design is no where good as a the cast iron head. So the big question is, why pay more for less?