5 port head weight vs K-head plus conversion kit.
Turbo Mini Forums

Has anyone compared the weight of a 5 port head with rockers, pushrods and carburettor etc and a k head, with conversion kit fuel injection and the like?

I guess there is probably negligible difference but still curious.

This is head, cams, bolts and cover.





Normal 1275 head weighs 13.8Kg, I guess approx the same, inc pushrods, rocker cover. I don't know how much the conversion kit weighs?

I know my 7 port if definetly lighter.

Edited by alaskanow0 on 18th Jan, 2015.

Class C 3rd Place Avon 2011 14.18 @101mph

Thanks. Is there anything you haven't weighed!

I was planning on going k head, but it would have comprised my 499kg target. Even though the extra 10bhp, is effectively the same as 40kg weight saving.

Edited by alaskanow0 on 18th Jan, 2015.

Class C 3rd Place Avon 2011 14.18 @101mph

Based on twinkam conversion been 5kg (6kg inc p&p on SC website), I reckon the the conversion kit be about 1kg heavier.

Class C 3rd Place Avon 2011 14.18 @101mph

I don't like the idea of the turbo stuff adding about 10kg on top of all that but that's just going to be the price to pay for serious peformance

The conversion kit was a bit heavier than i would have liked, you could make a good saving if you hogged out all the unnecessary material in the bottom cover for sure. There saving to be made on the jack shaft too. If done right i seriously doubt theres much difference between the cam drives.

The throttle bodies are closer to 1kg once you have removed all the useless bits and the k1200 fuel rail saves you a pressure reg too. They must be a big saving over a carb and manifold or 5 port injection?

I dont think theres much in it!

Is that some form of rule? 10bhp = 40kg weight saving? And vice versa?

So.. a quick look into this gave me this sum, please tell me if im wrong

Weight ÷ bhp = weight per horsepower, once this figure is worked out, then original weight ÷ new ratio = bhp equivelant to gain, e.g my rough workings... 692kg ÷ 130bhp = 5.32kg per horsepower, weightloss of 42 kg = new weight of 650kg ÷ 130bhp = 5kg per horsepower. Original weight of 692 ÷ 5 = 138.4bhp so 42kg weightloss is the equivelant of a 8.4bhp gain

Edited by D4VE on 19th Jan, 2015.