Powroll engines?

[JDiablo]

just checking out powrolls site and they have a nice 440 kit with a 89 mm forged piston,one of my questions is it comes with a 11.2:1 compression is that safe enough to run on 93 octane gas?and i was thinking their +4mm stroker crank to put it to 460 cc 850.00 for all of that,plus installation and needed parts...do you think that is good,but i need to DEF know about the compression and if the stroker crank is good,and yes im going to get a race cam,ported and polished head,valves,etc,etc

http://www.powroll.com/P_HONDA_TRX400EX.htm

[450ex]

had a 426 piston with powroll stroker

straight up da bomb

[JDiablo]

how much did it cost you for them to install it?or did you get it done somewhere else?

[450ex]

me and a buddy put it together

easier than i thought

used the internet to find a drawing

i had bigger valves
shortened guides
springs
cam
rockers
extreme port and polish(exhaust was a mirror, used polish compound)
port intake boot
41fcr
big bore lrd
4mm powroll stroker

with out a doubt the fastest 400ex i ever rode

torque monster
ran a 15-36 and took off in 3rd

[JDiablo]

word,you ported and polished it yourself?how much did you buy all that chit for neway?

[ghak99]

If you use the 11.2:1 on top of the stroker crank, you had better just plan on using race fuel. Normally the compression will increase when using a stroker crank.

[dj89]

i had them go my trx90 race engine it was fast as heck. hot to go racing in grand idland put mine to gether

[cals400ex]

Originally posted by ghak99
If you use the 11.2:1 on top of the stroker crank, you had better just plan on using race fuel. Normally the compression will increase when using a stroker crank.


i was betting that was 11.2:1 with the stroker crank, but maybe not. my buddy and i both run right around this compression. neither one of us has noticed a power gain by running race gas. we both tried it and it runs fine either way. the leaded race fuels may help keep it cooler though.

[JDiablo]

so then i should go with the 88. mmm piston then,i have no way of getting race gas,that is out of my way alot

[cals400ex]

you need to lower the compression, not go to a smaller bore. the bore size may do a little bit, but the compression is the main thing you need to watch. call themand see what they say.

[450ex]

i had the 11.2-1 piston

got all my stuff from T&T motorsports

they got every bit of it in stock

how many places got that

he hooked me up

we had a another buddy that had a full blown sparks stroker
while he was down getting refreshed we copied his head

got micrometers and measured all the depths in different places then copied my head to look like that

we both work in a tool room in a major factory so tools were easy to borrow if you know what i mean

after it was all said and done my bike would be his by a half a bike length every time in a 300yd race

only difference was he had a 39mm and i had a 41mm