9sec93

iTrader: (67)

i have a 239/245 duration, 604/576 lift cam on a 109 lsa. will i need to fly-cut the pistons with a stock short block and un-milled 241 heads? any help would be greatly appreciated.

KingSumthn

iTrader: (4)

considering your cam is smaller in size and duration than a trex and an ms4, which both fit without flycutting, i would assume no flycutting is necessary. thats assuming u are using the stock 241s and head gaskets

KingSumthn

iTrader: (4)

i meant lift and duration, not size

DONAIMIAN

iTrader: (18)

The only way you'll know is to measure. Thats a big cam on a tight LSA.

jshelton2006

iTrader: (15)

check it, but i'd say probably not...that's not as much lift or duration as ms4 which fits on stock heads and gasket.

JPH

iTrader: (2)

should fit, but you better check to see by how much.

BigKap94z

iTrader: (47)

My guess is that you would most certainly need to flycut with that cam. That cam is pretty large and on a tight LSA, you didn't mention if the cam was ground with any advance which would also cut down on PtoV clearance. These large cams that many others mention clear, but with minimal clearance, minimal room for installation error, and not anywhere near the amount clearance many would deem necessary. My cam is much smaller then that and on a wider LSA and is about as tight as i would want to run on the street. I believe the average clearance for a G5X3 on a 112 LSA was approx .070"/.110" and that cam is 5*/3* smaller.

hvyhttter

iTrader: (3)

better get out a sledge hammer and put a nice dent for the intake and exhaust valve. Im pretty good with a hammer if you need help

99mongooSS

iTrader: (4)

check it anyway but i doubt youll need flycutting. use a .055 head gasket. my ms4 has a .650 lift on the intake with a 239 duration and a 111lsa. the exhaust is a .609 lift on a 242 dur.

BigKap94z

iTrader: (47)

Did you actually check clearance?

99mongooSS

iTrader: (4)

nope, not on the old motor. I am on the new one, thats why I said check first. it worked for me with unmilled heads and stock thickness gaskets. Its on xer lobes and i dont know if that changes much as far as clearance it just has a fast ramp rate. Tsp designed the ms4 to have about .0060 on the intake and about 0.0080 clearance on the exhaust side. hope this helps.

rickyracer25

iTrader: (11)

It'll be tight and with that LSA I would say yes but you should check it

BigKap94z

iTrader: (47)

I agree with you on checking for sure. I believe that the clearance you typed is a typo with 1 too many zeros after the decimal point...but either way I consider that too close for a street engine. Many of these large cams that "clear" leave eyebrows on the pistons...

99mongooSS

iTrader: (4)

i did typo it but either way mine never left any eyebrows on mine and everybody i talked to said that i would have ptv issues but i never have

9sec93

iTrader: (67)

thanks for all the info guys. i know that some have cams with more duration and more lift than mine with no clearance issues. but none of those cams are on a 109 lsa. i will probably just take hvyhttter's advice and have him wack the pistons with a hammer just to be sure it will clear.

3timeracin

iTrader: (15)

well not that i know much but there is an article where carcraft took a 6.0 stock short block and installed a comp xer287 cam thats 238/242 and the lift is over .608+ on a 114ls and they clayed the stock pistons and used L92 heads with bigger valves and had more than emough room to me it looked like they had .150+ on both. Also on the exhaust it barely touched the clay ? You can google (L92 heads dyno) and you will see the build and where they clayed the pistons.