lstvr

Hi Guys,

My TVR has progressively got worse over a period of time, smoking on overun,
So i decided to change the valve guide seals this week, which i have done...

However 4-5 of the valves have too much play in them, i didnt measure but its plain to SEE..
It was a mixture of inlet and exhaust, and play is in a 360 degree plane, not elongated.
Has anyone else experienced this problem?
I will pull the heads of to rectify this over the winter, but summers are short over here so will continue to use them until they salt the roads!

I didnt look for this when i installed as they were new and fully built, and assumed they would be fine.

vettenuts

iTrader: (4)

This was an issue with Dart heads and several vendors stopped carrying them for this reason. One vendor I know of also said the guide centerline was not aligned with the valve seat center. Sounds like Dart had some QC issues. I had a very early set of Dart heads and they were overall very good. My oil consumption actually went down when I installed them. Seems like the QC worsened later compared to the set I had.

Do a search because if I remember correctly Brian Tooley made some measurements and found exactly what you did. There was also a major discussion on this on the hardcorels1 board but I don't think that board exists anymore.

lstvr

Hmmm..

I see, i will stick with them i think, have the work done and go with some heavier porting, and possibly stick lighter 2.08 valves in.

Its that or spend a **** load more cash on something trick like All Pro's...

lstvr

This is the problem!!!

S10xGN

iTrader: (11)

Can you "mike" the valve stems? LS valves are 8mm (0.3150") while old-school small-block Chevy valves are 5/16" (0.3125") for a difference of 0.0025". Possible the installer grabbed the wrong valves?

vettenuts

iTrader: (4)

A couple of people you can contact to get some information on this issue would be Ed Curtis at Flow Tech Induction or Bret Bauer at Bauer engines. They have both done quite a bit of work with Dart heads and Ed was getting bare heads to build a while back. Not sure he still using Dart products but he may be able to point you in the right direction. The valve stem diameter mentioned by S10xGN is also a quick check that could be made.

lstvr

Problem is I am in the uk, so have to do the work here.

vettenuts

iTrader: (4)

Understand, but it might be worth an e-mail to them to see if they can provide any insight.

Where in the UK?

lstvr

Birmingham, thats the second biggest city in the UK after London, Lots of engineering know how around here, where the UK's bikes and cars were made,sadly all gone to the wall...

If the wrong valves were fitted would the Collete not be ill fitting, and also valve length the same?

vettenuts

iTrader: (4)

I would think it would show some fitment issues.

My mom is originally from the UK which is why I had asked