valve guide play and others
Turbo Mini Forums

planning on getting these

http://minispares.com/product/Classic/Engi...k%20to%20search

valve guides fitted to my cilinder head allong with new valve's

http://minispares.com/product/Classic/Engi...k%20to%20search

http://minispares.com/product/Classic/Engi...k%20to%20search

( need to check length to be sure)

although i have a very good machine shop within an hour driving from here i still want to give up measurements myself to be sure.

so question is.
1 are these valves good for turbo use

2 how much play should they ream for? inlet and outlet.

3 they are going to cut the valve seats 2. anything in particular that i need to tell them?


greets.

also does any one have measurements for a dry deck kit? fancy on buying one but dont know if i have the room for one with the side mounted turbo.

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

Valve material dictates guide choice somewhat. The valves you've linked to are chrome plated so will run in either the bronze or iron guides. If you use the stainless valves you'll need to run them in the bronze guides.
What kind of spec motor is this ? How much boost ? If it's more than anything mild I'd be looking at using the stainless valves at least on the exhaust for sure.
As for guide clearance if it's a boosted motor Id be looking at 0.281" or so.
Is the head already fitted with the MG size inlet ? Or are you fitting it to a head with the smaller 33.3mm inlet ?

Phil.

WWW.TURBO-MINI.COM

the head is a mg head and those are the size valves that came out of it.

its a 1275 with standard turbo pistons no gap rings metro cam standard rockers double springs. side mounted gt1752 planning on running 10psi max ( only has an mpi pump to feed it) nodiz ignition so nothing special.

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

Those ex valves might be ok, but for the small extra cost I'd go with the stainless. Fit and forget then.
If you fit the inlets you linked to I'd put them in a lathe and pop a 30deg back cut on them and narrow the horribly wide seat to about 0.060". This will flow close to what the race valve does at half the cost. Put a 60deg throat cut on the head (and a 75deg if your machinist can do this) and blend into the port throat.

Phil.

WWW.TURBO-MINI.COM

phil did you mean .281 id ,as apposed to clearance ?

Medusa + injection = too much torque for the dyno ..https://youtu.be/qg5o0_tJxYM

So these for inlet then?

http://minispares.com/product/Classic/Engi.../classic/Valves 1275 triple groove collet.aspx|Back to search

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

You could use those inlets or you could do what I suggested above. I'd run the stainless ex though.

Yes I meant guide ID Robert, not clearance ! Lol

Phil.

WWW.TURBO-MINI.COM

so those are not the one from the link? where do i get them then? minispares only supplies those.

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

Still not have found those stainless steel valves.

I mesure 7.1 mm for the valve stem and 0.281 inch is 7.1374 mm so 0.0374 mm of play?

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

Still not have found those stainless steel valves.

I mesure 7.1 mm for the valve stem and 0.281 inch is 7.1374 mm so 0.0374 mm of play?

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

And been trying to translate this but guess my English isn't that good. So the valve needs a 60° cut and what is the seat? The angled part?
And the seat in the head also a 60 degree cut?

you can do anything if you set your mind to it...
i rather blow it up winning than keep it together losing.

finish date set for project 1... march 2018

https://www.minispares.com/product/Classic/...k%20to%20search

There's the ex valves. Regarding seat angles. The seat on the valve is 45deg, the seat in the head must match this. If you're using the race valves you don't need to do anything to the valve as they're already profiled for best flow. If you're using the road spec valves as you first linked to the seats are very wide and adding a 30deg back cut will improve flow and leave the seat (45deg) a more sensible width, 0.060" will do for the inlet and 0.075 on the ex. In the head match the seat (45deg) to the seat on the valve, then add a 60&75deg bottom cut to open the port throat and blend in to give around 88% of valve OD.

Phil.

Edited by Turbo Phil on 7th Mar, 2018.

WWW.TURBO-MINI.COM