by GuS » Sat Feb 03, 2018 2:53 am
Erik.
Thank for the nice words, but I believe you mistake me for a different Gus.
Noot, good summary, but you could also add, ....and check with measuring.
Venolia forged pistons.
They reccomend 0.005-0.007 at skirt for racing.
I measured a growth of 0.005 @ at 100 deg C (212 F)
I set them up with 0.007. (next one one the bench right now Im giving 0.006) Do they rattle cold? Yes!! Do they smoke? No!! Have I raced them? Yes!
Dixie/Superior repop
Reccomendation ... I dont know.
Measured 0.0019-0.002.
I set them up with 0.002 at skirt. I know one has been given some beating/raced. No issues.
T&O stroker 45 pistons
They really gave some strange results when measured hot. Seemed like they kept growing moore cam shape instead of being moore round when hot. I wouldnt reccomend any less than 0.004. Actually I have one set left on my shelve. I will give them some reshaping, remove some material from the side. Measure how the grow, and even consider to give them moore than 0.004
I know I have had one pair of OEM pistons out of the army wrapping. Just cant find my notes on that one. But as far as I can remember they gave less than the repop piston. But if that was as little as 0.0015, I honestly dont remember.
wz507.
The Enfield pistons are beauties..
I would really appreciate if you took your time to measure the piston hot/cold. Front to rear top and bottom of skirt. Sideways also, but since the sides are shaved off, that would only make sense to measure on just below the oil ring.
And what is being said here about toquing and distortion is true!! Torqueing has a lot of influence. Maybe moore on the flimsy wl base , than the Ks. And more on large ODs than std bore. No matter what clearance you give, the clearance will be ruined/lost unless you torqe the cylinders up to a plate for boring/honing. (I use top and bottom) If not, the cylls wil only be round when run on the hone. Once torqued to the crankcases they take any other shape than round, and start eating your rings, skirt etc. I have had wl cylls passing my hands where you could see the bore grooves at each base nut corner because they were clamped/torqed differently for boring than for honing.
GuS