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Author Topic:   Is this true???
BGA
Member
posted June 26, 2003 12:56 AM
Hello people,
Just a quick question. Friend of mine told me that his engine builder said that if we hang our speed pro hyper pistons on the rods backwards(dot to the rear) that it would increase torque????? Myself I think it is bull----, but I could be wrong. What do you all think.


ford5
Member
posted June 26, 2003 07:35 AM
the wrist pin hole in the piston is not perfectly centered on purpose, the reason that is, is because the piston manufacturers have found out that this reduces cold start up piston noise, if you were to reverse the piston on the rod it might give you a small amount more dwell time at the top of the cylinder, but i doubt if you could ever tell the difference in the seat of your pants lol. i would hang the pistons the way they were meant to be, and start looking for a more reasonable performance advantage, IMHO


mod4
Member
posted June 26, 2003 10:22 AM
Running Dodge 360's in Hobby Stock about 15 years ago, we did the same thing (offset the piston backwards) - the idea was to load the cylinder wall less. It never seemed to hurt anything.
As far as looking for "reasonable" performance gains, once things are sorted out it's alot easier sometimes to find 10 different 1hp gains then one 10hp gain ... imho.


sdhnc29
Member
posted June 26, 2003 02:49 PM
Your engine builder is correct . This is an old trick that has been around forever , and it does work .

Steve

------------------
Hendren Racing Engines
Rutherfordton , NC
(828)286-0780


BGA
Member
posted June 27, 2003 10:31 AM
Steve,
Could you tell me if this a noticable difference, and also are there any drawbacks to running the pistons like that.Thanks for the info and the help.
Bruce


BGA
Member
posted June 27, 2003 10:33 AM
Steve,
Could you tell me if this a noticable difference, and also are there any drawbacks to running the pistons like that.Thanks for the info and the help. Also could you tell me why this works like this.
Bruce


pipes
Member
posted July 02, 2003 10:10 PM
putting tyhe pistons on the rods backwards gives you the same gain that you might expect to find if you were to use longer rods.
while the gain may not be the same you are in effect getting the same result,longer piston dwell at tdc rlative to the amount of offset from center the pin is located.
1 thing to note is you will need to be using 4 eybrow pistons for this to work.
single eyebrow or trough type pistons as well as 2 valve relief pistons will not work since you have just changed where the valve reliefs are located moving them from the top to the bottom of the bore.
also make sure the pistons are actually built with offset not all are.


skinny
Member
posted July 03, 2003 02:38 PM
The one thing to be afraid of by doing this is that the piston skirts will take a beating, with the brittle pistons you are using, you will surely bread the skirts off over time, while not neccecarily blowing up right away, the balance of the engine will be all thrown out of whack.... Eventually, it will come apart


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