I have a new set of unassembled trick flow lt1 heads, and i just ordered my valves, and in putting it all together i noticed that some valves are looser in the guides than others, but still move freely so i wasnt too worries, then the last exhaust valve i put in was very difficult to get in, but so were the others untill they were all the way seated, then they freed themselves up, but this one is now stuck, i cannot even move it in the guide....what would cause this? im thinking ill just take them to head shop and have new guides installed so i know there correct size...any ideas though? any one else have problem with trick flow guides/heads?

 

The unassembled version, which may or may not have finished guide ID's for your valve stem diameter...aftermarket valves vary between .339-.342" and with a clearance of .0012"-.0016" Int/.0016"-.0022" depending on fuel type, guide/valve material, etc. it is easy to run into an interference problem if they have not been sized for your application.

As far as trick-flow goes for their finished guide sizes, I usually open them up by .0002" or so because out of the box they have tended to be to tight for comfort.

Take them in and have the guides honed and seats lapped to check concentricity.

 

awesome, thanks alot for the reply...ill be taking them in on monday

 

I have no idea of your skill or knowledge level, so the following could easily be a stupid statement. I trust you are not attempting to get a feel for the fit with the valve stem seals in place.

Getting a bit off topic, but the lone effective way that I have found to check accuracy of the seat concentricity is with an indicator mounted on a good fitting solid pilot. I've seen good looking lapped seats that were out of concentricity .004". So for me, lapping didn't show or prove anything.

Gary

 

no the seals were not in place...haha, i took them in today, and they do need work, so i guess next time ill know to look at that before i start to assemble them

 

I have a special tool for checking concentricity...
A lot of aftermarket heads are soo out that there is not a consistant lap line.

Concentricity is not as much of a problem as it was with older tooling, most seat problems come from having a height difference around the circumfrence of the seat...the seat width will be equadistant from the guide all the way around, but vary in its depth of cut, this can be due to having very sharp cutters and a machinist who doesnt take his time to cut the seat, or a head that has not been leveled correctly will cut more out of one side than the other.

 

Good for you for checking! Did you read the other thread where the guy was so ticked off that he was sent one NSA rocker in a set of SA rockers and never checked (neither did the installer). This stuff happens all the time.

Good advice from the machinist guy!

Rich