Clearance Problem?

[Topdowncruise]

I am just rebuilding my bottom end.Competition Cams recommended a cam which has 544 lift (with my 1.7 RR's) to go with my ported Y303's etc.Will I have a piston to valve clearance problem and/or stock valve cover issue?

 

[2002BLGT]

I am just rebuilding my bottom end.Competition Cams recommended a cam which has 544 lift (with my 1.7 RR's) to go with my ported Y303's etc.Will I have a piston to valve clearance problem and/or stock valve cover issue?

need to know what pistons you are running ?

 

[Topdowncruise]

I am not sure if this is what you are asking for but they are TRW forged aluminum with a compression distance of 1.619 in. which I believe is same as stock.

 

[Topdowncruise]

Intake/exhaust duration is 212/218 which is the 264HR-12 grind.

 

[srothfuss]

Only way to really be for sure on something like this is to get out some clay and check your clearance out.

Put some playdough or clay on top of a piston approaching TDC and manually bump the motor over. If the motor gets hard to turn, you should stop, unbolt everything and look at the putty. If you can see through the putty where the valve hits your in trouble. If the motor turns freely, take the putty out and measure the thickness of the depression with a caliper.


You don't want to trust the internet running that high of a lift. Or at least, I wouldn't

 

[green95gt]

I used a .542 lift cam with 1.7rr's with my gt40y heads and flat top pistons and didn't have a clearance issue.(exept with the valve cover which I had to change on my 95Gt) But everyone is going to tell you to measure. You don't want to take someones word for it, then go out and have a piston smack a valve and damage parts you've spent your money on. Good Luck!

 

[Topdowncruise]

Only way to really be for sure on something like this is to get out some clay and check your clearance out.

Put some playdough or clay on top of a piston approaching TDC and manually bump the motor over. If the motor gets hard to turn, you should stop, unbolt everything and look at the putty. If you can see through the putty where the valve hits your in trouble. If the motor turns freely, take the putty out and measure the thickness of the depression with a caliper.


You don't want to trust the internet running that high of a lift. Or at least, I wouldn't

Thanks for the measurement info and I am not confused about the need to measure. With the shipping and customs charges to ship from the US into Canada I wanted an indication that the cam had a good chance of having sufficient clearance before incurring those costs.

 

[srothfuss]

Thanks for the measurement info and I am not confused about the need to measure. With the shipping and customs charges to ship from the US into Canada I wanted an indication that the cam had a good chance of having sufficient clearance before incurring those costs.

Yeah, I thought of that after I posted... I hope I didn't sound mean. I wasn't trying to. I am pretty sure that the most lift on stock part is .550" So it's going to be close

 

[Topdowncruise]

Thanks.Hopefully it will measure out OK.