machine shop head issue. valve seat?
01-13-2005, 03:39 PM
#1
machine shop head issue. valve seat? I had "a machine shop" bore out my intake valve seats to 1.875" then i would blend them myself. well i messed up one valve seat with a die grinder, i knicked the seat. So i had them put a new valve seat in it. what they did was re bored the one to 1.93" my valve is 2.00" I asked the guy why he did this and he said the cutter went bigger than he thought. ya think?
so that valve would only have a surface seat of .035 vs. the .0625 i wanted.
I left it there and his boss is going to look at it tomorrow.
does anyone know what the minimum valve surface on the seat can be? it would probably work, but having one larger than the rest... wouldnt that cylinder get more air and run a little leaner?
also its for a turbo engine.
I usually avoid headwork at this place due to several probs w/ heads in the past. but i didnt think it would be to difficult to replace a valve seat.
so that valve would only have a surface seat of .035 vs. the .0625 i wanted.
I left it there and his boss is going to look at it tomorrow.
does anyone know what the minimum valve surface on the seat can be? it would probably work, but having one larger than the rest... wouldnt that cylinder get more air and run a little leaner?
also its for a turbo engine.
I usually avoid headwork at this place due to several probs w/ heads in the past. but i didnt think it would be to difficult to replace a valve seat.
01-13-2005, 11:16 PM
#2
Valve seat inside diameter I assume what you are saying is the shop opened up the inside diameter of the new valve seat to 1.93" straight down into the bowl. If this is the case, have them machine out that new seat and replace it. This diameter is too large for a 2" valve.
All the seats should be cut alike so you end up with similar flow. A .035" wide seat is insufficiently wide for a turbo motor in any case. On the intake seat, you need to have at least one bottom angle cut under the 45 degree seat angle, usually around 60 degrees which you blend into the bowl area either by hand or with multiple angles.
Steve
All the seats should be cut alike so you end up with similar flow. A .035" wide seat is insufficiently wide for a turbo motor in any case. On the intake seat, you need to have at least one bottom angle cut under the 45 degree seat angle, usually around 60 degrees which you blend into the bowl area either by hand or with multiple angles.
Steve
Originally Posted by pwrtrip75
I had "a machine shop" bore out my intake valve seats to 1.875" then i would blend them myself. well i messed up one valve seat with a die grinder, i knicked the seat. So i had them put a new valve seat in it. what they did was re bored the one to 1.93" my valve is 2.00" I asked the guy why he did this and he said the cutter went bigger than he thought. ya think?
so that valve would only have a surface seat of .035 vs. the .0625 i wanted.
I left it there and his boss is going to look at it tomorrow.
does anyone know what the minimum valve surface on the seat can be? it would probably work, but having one larger than the rest... wouldnt that cylinder get more air and run a little leaner?
also its for a turbo engine.
I usually avoid headwork at this place due to several probs w/ heads in the past. but i didnt think it would be to difficult to replace a valve seat.
so that valve would only have a surface seat of .035 vs. the .0625 i wanted.
I left it there and his boss is going to look at it tomorrow.
does anyone know what the minimum valve surface on the seat can be? it would probably work, but having one larger than the rest... wouldnt that cylinder get more air and run a little leaner?
also its for a turbo engine.
I usually avoid headwork at this place due to several probs w/ heads in the past. but i didnt think it would be to difficult to replace a valve seat.
__________________
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
Steve Demirjian
Race Engine Development
Oceanside, Ca.
760-630-0450
web: www.raceenginedevelopment.com/
e-mail: race-engine-development@***.net
01-14-2005, 01:01 PM
#4
Originally Posted by Steve - Race Eng
I assume what you are saying is the shop opened up the inside diameter of the new valve seat to 1.93" straight down into the bowl. If this is the case, have them machine out that new seat and replace it. This diameter is too large for a 2" valve.
All the seats should be cut alike so you end up with similar flow. A .035" wide seat is insufficiently wide for a turbo motor in any case. On the intake seat, you need to have at least one bottom angle cut under the 45 degree seat angle, usually around 60 degrees which you blend into the bowl area either by hand or with multiple angles.
Steve
All the seats should be cut alike so you end up with similar flow. A .035" wide seat is insufficiently wide for a turbo motor in any case. On the intake seat, you need to have at least one bottom angle cut under the 45 degree seat angle, usually around 60 degrees which you blend into the bowl area either by hand or with multiple angles.
Steve
yes that is what i meant. all the seats were .062 wide except the one they did. they tried telling me that the wider bowl wont effect anything because there is that much variance between ports in stock heads anyways.
I cant beleive they would expect me to beleive that. and accept their $hyt work. regardless they are making them right for me. I just have to tripple check everything, make sure the seats are at the right (same) height. No way am i having them assemble them.
thanks for the info.
