Piston modifications

[lt250racer]

What are some piston modoifications that I could do to my lt's piston? I have heard about piston porting.....whats this? What exactly will it do to help the engine? Finally, is it worth it? Thanks, Travis

[gassrx.com]

put the piston in the bore mark the transfer port angle onto the piston with a scribe. then cut trenches were the scribe marks are. don't remove alot. just to add better air flow. don't cut into the ring land . windows in the intake skirt. clean under side removing casting flaws or machine marks. just round them. oil drilling in piston pin . under side put a chamfer/ bevel the hole.. remember this for race apps only. should be do with rifling files. not the dremel. unless you are skilled with one....hate on yourself to slip and ruin the piston. some of these mod like i said are race apps 20 minute race yes then a rebuild. not the go ride weekend at a time. it reduces the life of the piston, if over done.... take your time remember it is moving at 8000 rpm or 133.333 times a second. ring end gap is probably most important thing to do

[lt250racer]

Good info, thanks....

[CR480R]

Originally Posted by gassrx.com

put the piston in the bore mark the transfer port angle onto the piston with a scribe. then cut trenches were the scribe marks are. don't remove alot. just to add better air flow. don't cut into the ring land .

wouldn't cutting trenches into top of the piston interfere with the squish characteristics and port timing?

[gassrx.com]

trenching meaning round the piston edges at the port openings and yes the compression will need adjusted if alot is removed. i said don't remove alot cause of unfavorable thing can happen.. port timing is controled by the rings not the top of the piston. oh and i forgot ceramic coat the piston crown , and dry film the piston skirt. next re pin the piston to the exhaust side. now you can cut the transfers wider........,,,,//>,,><,./,./,<,./,<<<, race app don't try this at home consult a doctor and see if the surgery is right for you. symptoms blurry eyes arm, pump and a large rush of adrenaline

[flotek]

theres lots of tricks that can be done to your piston to improve response and lowend ..but all of which wil l ultimatley shorten the life of the piston t o some degree IMHO ,2 horsepower isnt worth a new topend and bore job ....ive personaly see n too many of them crack or prematuraly wear ,if it were a drag motor thats inspected often then maybe it would be worth it

[CR480R]

Originally Posted by gassrx.com

port timing is controled by the rings not the top of the piston

Then why would you lower the top edge of the piston?

Originally Posted by gassrx.com

next re pin the piston to the exhaust side. now you can cut the transfers wider

Can you elaborate on this?

[gassrx.com]

Originally Posted by CR480R

Then why would you lower the top edge of the piston?
IT LETS THE AIR FLOW OVER THE PISTON LIP. REDUCING TURBULANCE MORE FLOW BETTER YES



Can you elaborate on this?

REPINNING THE PISTON. MOVING THE PINS TO THE EXHAUST SIDE ,SO ON THE BACK SIDE/INTAKE YOU CAN CUT THE TRANSFERS AND BOOST PORT WIDER. THE CYLINDER NEEDS TO BE NEW TO HOLD THE RINGS ON THE EXHAUST BRIDGE FROM POPPING OUT. WORKS GREAT

[lt250racer]

I assume that removing alittle from the top of the piston (around the transfer ports) will allow for better/quicker air flow. As for repinning the piston, I understand that the two pins need to be moved to the exhaust side to allow for the transfer ports to be widened. Why does it have to be a new cylinder sleeve?

[flotek]

rasing and lowering the intake windows and adding a boost port above the windows does help response and start the charge sooner for lowend snap ...is it worth it wel lthat depends on the application ..now as far as modifying the edge of the crown .. i wouldnt touc h anything else like that , but thats just my opinion