TURNING PISTONS 180 GETS 30 HP?????

[XBLCanterX]

I was talking to a buddy of mine who builds 302's for some local mustang guys and he told me that if you turn the piston heads 180 degrees in the cylinders it'll get you around 30 extra HP. I said BS...but he says hes got Dyno numbers to prove it. I will have to wait and see...but has anyone else heard of this? He said it bumps up the CR because you move the larger intake reliefs to the flat spot of the chamber and use the smaller exhaust reliefs instead. Makes sense but wouldnt that cause clearance issues though??? Just wondering if its true.

 

[Green4.6GT]

ive heard of that before, but it sounds like bs to me

the CR shouldnt go up, there is still the same volume of air in the cylinder, its not like you removed the valve releif, just moved it.. i could be wrong tho

 

[Stangler]

I was talking to a buddy of mine who builds 302's for some local mustang guys and he told me that if you turn the piston heads 180 degrees in the cylinders it'll get you around 30 extra HP.

I also have heard of this, but it is because it give's the piston more leverage on the rod. Move's the piston pin at TDC to the correct side of the leverage point and a increase of power is the result. I've heard of gains, but not 30hp. Also, tends to have a lot of piston noise untill engine is warm.


Nate

 

[Green4.6GT]

I also have heard of this, but it is because it give's the piston more leverage on the rod. Move's the piston pin at TDC to the correct side of the leverage point and a increase of power is the result. I've heard of gains, but not 30hp. Also, tends to have a lot of piston noise untill engine is warm.


Nate

that makes more sence than the retarded compression idea lol

 

[giddyup306]

NO!!! Piston pins are offset to reduce wear on the major thrust side. By rotating it 180*, you will cause MORE friction and INCREASE the wear. Do not do it. Piston mfr.s know what they're talking about. If there was any sort of gain involved with doing such a swap they would tell you to install the pistons in that fashion in the first place.

 

[XBLCanterX]

I was just wondering cause the guy who told me this seems to know his stuff. Ive seen several of his car run at the local 8th track, all with times in the high 6's. Two of which are NA. theyre badass

 

[Stangler]

NO!!! Piston pins are offset to reduce wear on the major thrust side. By rotating it 180*, you will cause MORE friction and INCREASE the wear. Do not do it. Piston mfr.s know what they're talking about. If there was any sort of gain involved with doing such a swap they would tell you to install the pistons in that fashion in the first place.

Yes,.. there is more wear and tear,... but from the people I've talked to this is not a big thing for a strip/stock elim/NMRA class legal type car that it would be used for. daily drivers need to build it the right way.

 

[tmoss]

Longevity in a race engine isn't an issue - it is in a street car for most guys.

 

[Scorcher2005]

as giddyup said...
if turning the pistons around would get you more horsepower, then why dont manufacturers tell you to put the pistons in that way?

 

[giddyup306]

I've heard of it before as well. Even saw some artcles on it. Don't beleve everything you read or everything that people tell you. If you turn a 347 piston around you run into big problems. Even if one piston is turned around.