2.85L complete short block FS
08-27-2003, 07:47 PM
#31
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Konstantin
I don't know if I would agree with that.
All I had done was some bowl/transition reshaping done which is a far cry from doing an entire head.
But I see your point...
I don't know if I would agree with that.
All I had done was some bowl/transition reshaping done which is a far cry from doing an entire head.
But I see your point...
08-27-2003, 08:04 PM
#32
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Konstantin
Did you get your head gasket problem fixed?
Did you see the photos explaining how the inner part of the head gasket can not be aligned properly, etc...?
Did you get your head gasket problem fixed?
Did you see the photos explaining how the inner part of the head gasket can not be aligned properly, etc...?
08-27-2003, 09:27 PM
#33
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it was not my head it was from a friend. (my engine still runs after 240000 km and teh first headgaked was replaced after 12 years :-)
#2 cylinder was blown on my friend gasket. The coating on the gasket was burned from the combustion gas. it seems that the head was not preperly torqued.
He used the 20 Nm, 90 degree, 90 degree Porsche specification but I remeber that the head using the factory spec it is always at least 90 NM torqued. well his head was at about 75 NM only. He used ARP studs and nuts.
maybe the factory specs are just for the factory hardware and not for the ARP or raceware studs.???
no I didn't saw the photos about the head gasked aligning.
what is the direct URL for this?
according to some guys in germany the max you can win from Porting and polishing is about 7-15 HP.
for more HP you ned other valves cam etc. Not sure if it is worth on a Turbo engine you can spend teh same money on a Autronic or DTA and you have much better results.
Konstantin
#2 cylinder was blown on my friend gasket. The coating on the gasket was burned from the combustion gas. it seems that the head was not preperly torqued.
He used the 20 Nm, 90 degree, 90 degree Porsche specification but I remeber that the head using the factory spec it is always at least 90 NM torqued. well his head was at about 75 NM only. He used ARP studs and nuts.
maybe the factory specs are just for the factory hardware and not for the ARP or raceware studs.???
no I didn't saw the photos about the head gasked aligning.
what is the direct URL for this?
according to some guys in germany the max you can win from Porting and polishing is about 7-15 HP.
for more HP you ned other valves cam etc. Not sure if it is worth on a Turbo engine you can spend teh same money on a Autronic or DTA and you have much better results.
Konstantin
08-27-2003, 09:44 PM
#34
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Konstantin
I use 15ftlbs/45ftlbbs/75lbs for my head torque specs.
As far as porting goes... you guys in germany are incorrect. The head/cam on my engine was worth over 50rwhp at any given boost... and that's using stock valve sizes.
For instance... I'm at 350RWHP at 13 psi boost.
The dyno runs I did before put the car at about 300RWHP at the same 13psi boost which is about right for a 2.5L with the typical bolt-on modifications.
Note: Although the compressor of the turbo was the same, and the exhaust wheel was the same, the exhaust housing was different, but the a/r of the exhaust housing was the same.
Note2: A SFR 4 into 1 header was used.
So possibly the differrence would be less for an exact apples-to-apples comparision, but it wouldn't make more than 10RWHP difference in my opinion.
On a turbo, the exhaust port, exhaust velocity, exhaust-to-intake valve ratio, and the exhaust cam timing is extremely important on a turbo, and is why I spent $4000 on a JME head/cam/valvetrain.
Now the intake side is a different story... Concerning the intake porting, I would agree with your friends. But not on the exhaust.
I use 15ftlbs/45ftlbbs/75lbs for my head torque specs.
As far as porting goes... you guys in germany are incorrect. The head/cam on my engine was worth over 50rwhp at any given boost... and that's using stock valve sizes.
For instance... I'm at 350RWHP at 13 psi boost.
The dyno runs I did before put the car at about 300RWHP at the same 13psi boost which is about right for a 2.5L with the typical bolt-on modifications.
Note: Although the compressor of the turbo was the same, and the exhaust wheel was the same, the exhaust housing was different, but the a/r of the exhaust housing was the same.
Note2: A SFR 4 into 1 header was used.
So possibly the differrence would be less for an exact apples-to-apples comparision, but it wouldn't make more than 10RWHP difference in my opinion.
On a turbo, the exhaust port, exhaust velocity, exhaust-to-intake valve ratio, and the exhaust cam timing is extremely important on a turbo, and is why I spent $4000 on a JME head/cam/valvetrain.
Now the intake side is a different story... Concerning the intake porting, I would agree with your friends. But not on the exhaust.
08-27-2003, 09:52 PM
#35
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yes but they said only port and polishing in the intake side brings max 15 HP.
no other exhaust Porting, no other "better" cam, no other header etc.
just the intake side;-)
Sure with all the job you made (and paid) you sure get more HP;-) Cam and header can delivers some HP and teh exhaust side work too.
if I remeber corectly you had a Powerhouse head with Ported intake that gave you almost no gain on your previous engine but this was 3-4 years ago right?
Konstantin
no other exhaust Porting, no other "better" cam, no other header etc.
just the intake side;-)
Sure with all the job you made (and paid) you sure get more HP;-) Cam and header can delivers some HP and teh exhaust side work too.
if I remeber corectly you had a Powerhouse head with Ported intake that gave you almost no gain on your previous engine but this was 3-4 years ago right?
Konstantin
08-27-2003, 10:33 PM
#36
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Yes I had a Powerhaus head. Stock valve sized, stock cam, ported intake ports (minor porting).
I never noticed a difference, and other people with similar modified cars with stock heads were getting very similar dyno results at the same boost levels...
My conclusion is that it wasn't worth it especially if you are running a stock intake manifold which is pretty closely matched to the stock intake ports....
I never noticed a difference, and other people with similar modified cars with stock heads were getting very similar dyno results at the same boost levels...
My conclusion is that it wasn't worth it especially if you are running a stock intake manifold which is pretty closely matched to the stock intake ports....