Author Topic: Cam Swap  (Read 10503 times)

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gashousegorilla

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Reply #15 on: January 23, 2020, 01:54:51 am
Both the AVL and cast iron Bullet cams run on 5/8" O/D spindles, which is around 15.88mm, and a round 15.88mm if you're really lucky! Retro-fitting Bullet cams to an AVL is an option, but probably not for a UCE/EFI, as the gear tooth shape seems to have been changed, and as the UCE crank pinion is machined as part of the timing side shaft you can't do a wholesale cam and pinion swap.

The adjustable cam spindle thing was, I believe, an attempt by the factory to cut down on timing gear rattle, but it is of course something else to work loose and go out of adjustment. My AVL hybrid engine happily uses the old solid spindles - theses engines will never be totally silent mechanically.

A.


 Yeah, I hear ya.... 15.80- 15.84 on  BRAND NEW  UCE's  Cams  depending on where in that bush you measure them ... haha !   The UCE's also run cam gears that are different sizes.    The exhaust gear is  52.51 diameter and the intake is a 55.06.       38 tooth Cam gear on the UCE's.... 36 on the AVL's  and Iron barrels ?   
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.


ace.cafe

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Reply #16 on: January 23, 2020, 04:23:19 am
We will just get some bushings made at the machinist. It will cost more, but it will get done, and he can move along with the project.
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Adrian II

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Reply #17 on: January 23, 2020, 02:54:42 pm
Quote
38 tooth Cam gear on the UCE's.... 36 on the AVL's  and Iron barrels ? 

40 tooth on the AVL and iron barrel cam gear, cam spindles on (nominally!) 2" centers in accordance with the old Redditch design.

A.
Grumpy Brit still seeking 500 AVL Bullet perfection! Will let you know if I get anywhere near...


gashousegorilla

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Reply #18 on: January 24, 2020, 10:38:05 pm
  Got it.   Thanks Adrian.
An thaibhsí atá rattling ag an doras agus tá sé an diabhal sa chathaoir.


SKR

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Reply #19 on: June 02, 2021, 11:55:51 am
  The bushings inside those cam gears... over time and miles... will take on the shape of those eccentric spindles.   So the gear teeth will mesh tighter and looser  from one side of the gear to the other.   This is why the recommend readjusting the gear lash in the book after a certain amount of miles.

@gashousegorilla, i am trying to adjust the cam on my classic that has run 2500Kms, and i keep getting valve train noise even though i adjust them. May be the bush may have worn due to incorrect adjustment and as you have advised, i certainly have the gear teeth mesh tighter and looser on exactly opposite sides and the other two sides mesh normally(if we mark the cam into 4 quarters). how would you suggest to adjust the cam here to avoid cam gear noise? It really feels bad to hear such out of sync noise on a brand new machine.


TrianglePete

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Reply #20 on: June 03, 2021, 11:56:56 am
The cams from the UCE engines are inaccurate in all dimensions.

It is rare to find 2 the same....   A little noise from a 535 single ????


SKR

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Reply #21 on: June 03, 2021, 05:07:47 pm
The cams from the UCE engines are inaccurate in all dimensions.

It is rare to find 2 the same....   A little noise from a 535 single ????

@TrianglePete, thanks for the response.
Would you say that there is no way to reduce the cam noise from the engine because of the inaccuracies the company has dialed into each of those cams? i was wondering if replacing the cam with a new one would reduce the backlash noise from the cam?


TrianglePete

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Reply #22 on: June 04, 2021, 10:31:26 am
I have purchased many sets from India. Very few are perfect.

After many miles of testing parts with a 2013 C5 and a 2014 GT 535   The 535 just seems to be a noisier

engine design.  Possibly because of the different case material and slightly different design. Some find the

sound pleasing ??   Even in stock form  It makes more sound....

        Some things I have learned about 535s       If you install the heavier C5 crank it stops the stop sign stalling

If you install a larger duration exhaust cam only you gain performance without changing computer settings.

        All the UCEs come with 350 cams.   They should be changed to get true 500/535 performance.