Tappet clearance
Tappet clearance
Author
Discussion

malc_grn

Original Poster:

48 posts

231 months

Saturday 9th January 2010
quotequote all
Just checking the clearance on the tappets on my 4.5 and just want to claify what they should be.
Mine are as follows:-

Exhausts: 7 are 0.010 and 1 is 0.095

Inlets: 7 are 0.004 and 1 is 0.006

Am I right thinking that the Exhaust should be 0.010 and Inlets 0.008?

What tolerance should I work too, i.e. is 0.095 on one of the exhaust ok left as that?

Thanks for your help

itiejim

1,822 posts

235 months

Saturday 9th January 2010
quotequote all
Yep - inlets 8 thou, exhausts 10 thou - though I believe that TVR later changed this to 10 and 12 thou respectively. This would certainly be "safer" as a loose valve is less of a worry than a tight one, but I'm not sure whether there is any noticeable difference in performance.

Although 9.5 thou is close enough, if you've got to have the cam out anyway I'd be inclined to get it right (or if anything a bit loose).

Tanguero

4,535 posts

231 months

Saturday 9th January 2010
quotequote all

malc_grn

Original Poster:

48 posts

231 months

Sunday 10th January 2010
quotequote all
Thanks guys

A load of useful info there, as I definatley need to adjust the inlets I'll change them all to 10 thou inlet and 12 thou exhaust

Cheers

FarmyardPants

4,379 posts

248 months

Monday 11th January 2010
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One of your exhausts is 95 thou (ten times too much) unless you meant to say 0.0095 </pedant mode>

malc_grn

Original Poster:

48 posts

231 months

Monday 11th January 2010
quotequote all
Yeah my mistake, it did measure 0.0095

Cheers

julian64

14,325 posts

284 months

Tuesday 12th January 2010
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Replied to the wrong thread Doh!

I meant to say that increasing your gaps would improve low end emissions and probably running, but will knock a significant amount of power off the top end.

Possibly not a problem in this weather.

malc_grn

Original Poster:

48 posts

231 months

Wednesday 13th January 2010
quotequote all
julian64 said:
Replied to the wrong thread Doh!

I meant to say that increasing your gaps would improve low end emissions and probably running, but will knock a significant amount of power off the top end.

Possibly not a problem in this weather.
So what gaps would you recommend, stick to factory settings?