Finally finished it!

[Mattius]

Finally finished my cylinder head, well chuffed with it, took me a month but well worth it, just waiting on the massive new valves to arrive so i can get the seats cut again.
in the middle of polishing and lightening a set of rockers to go with it.

 

[agw_01]

What's it from?

Looks shiny

 

[Enfield]

And what is it for?

 

[Mattius]

its my 8port triumph spitfire 1500 head, which has been port polished and gas flowed, soon to be followed by massive valves uprated rocker gear, kent valve springs and a nice kent cam shaft which should give me a nice 110bhp in a car that weighs 800kg

 

[agw_01]

Cool. Did you port it yourself? What's the standard power output of the car?

Looking to get my head ported in the future.

 

[Enfield]

Only 110bhp? What is it as standard?

Get some twin 40's on it or something.

 

[Nitro_Junkie]

very nice work, but I wouldn't worry too much about lightening the rockers, it has very little overall effect, the main area where weight saving is recognised in performance is the pushrods (unless its OHC, not clued up on the engine) and valves

 

[Mattius]

standard is 78bhp, twin 40's will come later or hopefully a set of delertos instead.
porting was done myself with advice from the pro's, the aim is to get as much as possible out of the standard spec engine so i can still race it in classic for on hillclimbs etc. could have changed the engine but that limits the racing options. max you can get out of one of these things in total race spec is about 130bhp so i'll be happy if i can get 110 just now

 

[Mattius]

lightening the rockers is all part of the overall plan, combined with having everything balanced, and the flywheel and crank lightened it will lighten the rotational mass of the engine and improve efficiency.

 

[Enfield]

Ahh I see. Sorry, didn't realise that it was 78bhp as standard - that's a pretty damn good gain then to go from that to 110bhp.

Is the car stripped out or does it have that weight from out of the factory, (weighs about the same as mine ).

 

[Mattius]

thats factory, i haven't even got round to weight saving yet. the 110 hasn't just come from the head, reacon im at about 86 at the moment. reacon i can get about 20 out of the cam and the head.

 

[saitrix]

Looks like you're doing well with the Spit, should be able to lower the weight a bit to help it out. Should be fast though with 110bhp.

 

[Chabsy]

I think you're gonna need some ballast in the boot

 

[Mattius]

rear wheel drive, no need for that.

overall change the bellhousing for an alloy one, lightweight flywheel, few other lightweight bits and i should have a car lighter than an elise with the same comfort (mx5 seats are the comfiest i have found) and almost the same power.

 

[IainB]

Finally finished my cylinder head, well chuffed with it, took me a month but well worth it, just waiting on the massive new valves to arrive so i can get the seats cut again.

Are you going for a 3 angle cut on the seats?

and these are big valves (though the new ones are even bigger, and yes, thats a 50p!)

 

[Nitro_Junkie]

ahhhh proper sized valves Iain what size is that? we run 2.18" intake in the rat

Matt, I know and see where you're coming from - and it could be different with your engine I don't know (what rockers are you using btw?) but theres not too much point in doing too much lightening to the rockers, might make a slight change but will lose durability more

 

[Mattius]

yeap seats will be cut 3 angle serdi style, i don't think my valves will be quite as big as that.

 

[silversurfer]

That will make a very nice candle holder for your dinner table

 

[Mattius]

standard triumph rockers are being used, i know that lightening them doesn't make too much of a difference but whilst im signed off work for 2 broken ribs and a lung infection i need something to occupy my time.
as for the head it seems to be causing quite a stir on the triumph forums with some of the racer guys slating it for not going to work cause they have never seen it done before. The bit in question is the conbustion chamber wall opposite side to the spark plug, i have flowed this with a varying bevel, as suggested by one kas kastner ex head of the triumph competition tuning department.

 

[Mattius]

thought id show you an update of the finished head, just needs a skim and the valve seats cut/guides placed. and then its good to go, im so looking forward to getting it on the car and getting the performance.
Also added the contraversial feature of somender singh groove technology, not sure if it will work but there has been no negative things reported about it.