Hi!
help me please!
Donor - Porsche 944 1989, 2.7 liter (non-turbo) engine code M44.11
Project - 2.7 turbo


What are the exhaust valves should I use?
The factory (944.105.41800) for 2.7 liter?
or ?
Turbo (951.105.416.07) for 2.5 liter?


I am afraid that the factory exhaust valves for 2.7 Liter cylinder head can not withstand high heat and crumble.

I read that a lot of guys here have done a turbo motor + 2.7 liter cylinder head.

These valves have the same diameter dish of 40 mm.
But the valve from the turbo cylinder head at 1 mm longer than the valve from 2.7 liter cylinder head.
This may be the problem? Or hydraulic lifters will solve this problem?

Give me the right advice

Sincerely, Sergey

 

I have 951 exhaust valves in my 951 head, though do not know how the machine shop addressed the extra 1mm you mention.

Trust you know you should use stronger lower compression pistons and stronger rods if you turbo that motor. Also, if going to all the trouble, you are just one crankshaft shy of a 3.0 liter motor...

 

Are you turbo charging a N/A 2.7? Wow well if you don't want to drop the compression look into E-85 and water injection either will let a hi comp turbo motor live.

A good machine shop could fit those valves for you. Personally unless you already have a 951 donnor for parts, I'd go with a V8!

I have a 89 Turbo S and an 85.5 N/A and if the N/A motor goes it would get a Chevy motor!

However to your point other than machining for the new valves you could also get the 2.7 head Cryo treated.

 

From where Sergey might come from there may be no need to cryo treat anything.

 

 

It wil still break eventually unless you stay under 13 psi. Pistons and rods would be high on my priority list.

Personally I wouldn't worry about the valves too much, unless you are tracking it extensively.

 

Rogue Ant tried turbo'ing a 2.7. I think it worked for about 8 or 9 months, then a piston got destroyed. He was running E-85 according to his alias. I imagine he was using the turbo exhaust valves though.

 

It was a 2.5. I ran one for about a year at high boost but it also broke ring lands

 

Thank you very much. It's really interesting information.

Of course, the turbo motor I am building on the good parts

Cylinders of the engine block is cast-iron liners = soon

Crankshaft, I do not know how to? I have a factory crankshaft from my engine. I have additionally purchased from S2. I doubt if you put the crankshaft of S2 has to do with balancing shafts? Leave inflow discharges from my engine 2.7 or need to put on the S2?

JE FORGED CERAMIC COATED PISTON SET FORE A 4.100" = already bought
(COMPRESSION 8.0)

Oliver Rods = already bought

Cometic Head Gasket Porsche 944 2.7 3.0L 106mm .051 MLS = already bought

Kevlar Racing Timing Belt = already bought

Oil Coller = already bought

Radiator from 944 turbo = already bought

Intercoller = already bought

KEVLAR CLUTCH KIT = will soon buy

Brake Calipers + knuckles on 944 turbo S = already bought

Wheels Dezing 90 on 944 turbo S = already bought

Exhaust system = has not yet chosen
================

Now my question is, what better exhaust valves used in 2.7 cylinder head - stock or turbo?

 

Turbo valves are sodium filled and better suited for high heat applications. If they're 1mm too long, you could probably have a machine shop take them down 1mm.

 

All true. That's what I wanted to do. Thanks for the tip!

 

Turbo valves I put new valve guides (from the turbo).
What to do with the valve seats? They also need to change?
Remove the valve seats from the air valve and put the valve seats on the turbo valves?
Or is it extra work?

 

help me, please

 

Sergey, welcome to RL! Tell us a little about yourself, your previous Pcar experience, etc.

 

Well.
Where better to put photos of Porsche ?
in this topic or have a separate section?