Head Mods
Turbo Mini Forums

No iain, not sandblasted it yet it is gray primer you can see just so it made the gasket line easier to mark out. Gonna sandbast it before painting. Needs surface gringing aswell

Edited by mikemph on 17th Mar, 2005.

Middle 2 exhaust ports





Inlet

What tools are you using to do the work ? and how much time and cost have you got into the head sofar.

Two things are infinite: the universe and human stupidity; and I'm not sure about the the universe.

Have you got the guides in there??

Just using air die grinder, seletion of burrs to rough out and grinding stones to ploish out, with flapwheels to buff.

Taken about 8-10 hours in all

No guides yet, got to press them in once they arrive.

I'm going blind.. :( Sorry Mike.

Edited by Doodmeister on 21st Mar, 2005.

Two things are infinite: the universe and human stupidity; and I'm not sure about the the universe.

I thought I just did!!!!

Tunstung carbide burrs, mostly ball ended type and just grinding stones shaped to a ball shape

yep its in the right direction , but ultimately the most volume and chamber depth needs to be around the plug , maximise squish according to what pistons you are using with a +0.005 " thou deck hieght, and maybe deepen the piston dish if ness

I measured my head and it has about 12 mm deep chambers. That´s 0,47" to you imperial lot.

I'm not sure that many on here use 'pounds, shillings and pence' Jukka!

I'm in a fun phase of working with Americans who are meant to be designing in metric - but are cheating by doing it all in imperial with the intention of convering it when the design is all finished. I can see silly dimensioned drawings coming up with two or more decimal places on random numbers.

Sorry havent updated for a while I will take some pictures soon as I have had the unleaded seat s fitted. Should I go with the sodium filled valves or go stainless? Either way I will have to buy the valves as it was a NA head

When I chose the valves for my head I went for stainless steel. At the time i had heard storys of sodium valves dropping heads, But I dont think anyone on here has atually experianced this.

+ The soduim valves are so thick im sure they do not flow as well as other racing stainless valves, but I have no proof or technical data to back this up.

The stanless valves I use are 30mm in size, I think the metty turbo uses 29mm, again not really sure how much difference this makes tho

Think stainless is the order of the day then. About the same price if not cheaper than sodium filled anyway

I use stainless valves, I will never use sodium filled again, I have seen too many failures

Team Racing

I was thinking rimflow exhaust and normal stainless inlets. Think the sharp edge of the inlet might get hot and cause detonation any thoughts??

I have used Rimflos with turbo since 1996 and they have been absolutely reliable. No signs of detonation. The inlet have seen 42000 miles, current 31 mm exhausts 20000+ miles. The first head had 32 mm valves from Stuart.

Well looks like rimflow all round then

here is a picture of the turbo on the manifold VNT15 have to wait and see if it can stand the heat

Edited by mikemph on 5th Jun, 2005.

Looking good mike, I have just started to redesign my first draft from Solidworks, but have only done most of it off of a small bore head just to cover my CAD assignment at college. Now i am covering it for my Second year project i am going to do it properly! So gotta get me a nice Engine and start the making/ flow bench work and then getting my engine done!!!! Antman

looking good mike

Team Racing

cheers just hope it all works lol. Nothing to lose by giving the VNT a try.

How are you going to actuate the clutch?

ahh I am glad someone noticed. I will do from the timing chain end via an adjustable rod to the clutch arm like the janspeed set up which the wholw set up is closely based on.

I will have to put a slight bend in the arm to clear the turbo. Although I have been looking into actually making a direct acting cylinder in the housing with a bearing on the end. Need to do a few calculations and work out the bore of the cylinder see if it is possible to modify the housing to suit.

Putting the cylinder in the hosing would also keep it away from the exhaust and turbo heat.

Edited by mikemph on 5th Jun, 2005.

I remember seeing a picture of the Janspeed clutch cyl mounted the other end, sounds a good idea, doing a direct acting slave to me sounds like a lot of hard work adapting the end casing and we all know how fussy mini clutches can be about the correct amount of throw etc...

exactly!!!!

Thats what I was thinking about the travel just have to give the long pushrod idea ago for now and see how it goes