Trav’s Race Build: from B6 to Big Bore BP-Z3

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StanTheMan
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Re: Trav’s Race Build: from B6 to Big Bore BP-Z3

Postby StanTheMan » Wed Apr 06, 2022 7:35 pm

I can assure you, as long as you get the timing right you'll be fine. I would perhaps check clearance once you have the adjustable cams on . insure your valves dont hit the pistons while doing major adjustments with the cam sprockets.

also insure your bolts on the cam sprockets don't come undone.ever!!! fullstop!! its messy and expensive .


Camgear is toast.jpg



:oops: :?
bent valves , and broken valve guides.... and little compression. LOL
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Re: Trav’s Race Build: from B6 to Big Bore BP-Z3

Postby PaulF » Thu Apr 07, 2022 8:54 am

Ouch. I was advised that if you ever use a set of cam gears that aren't top of the range, the first thing you do after taking them out of the box is change the bolts for some known high tensile ones.

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Re: Trav’s Race Build: from B6 to Big Bore BP-Z3

Postby rascal » Thu Apr 07, 2022 9:48 am

I changed the bolts on mine as they looked dodgy, However this didn't help when the gears were manufactured with the nubs 120degrees out. :evil:
So much for buying from a reputable vendor. :roll:

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Re: Trav’s Race Build: from B6 to Big Bore BP-Z3

Postby StanTheMan » Thu Apr 07, 2022 10:58 am

I ended up with good quality ones. Cost a bomb but no breaking. also with the BP4Whead they have to have the magnets to go past the cam angle sensor. The magnets in the previous ones stuck out too fare & hit the sensor.

The Maruha one are a precision cam gear. Also no guesswork with lining up marks. there wasn't any marks on those previous cam gears. so I had to actually count teeth to make sure i put the ref in the correct space
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Re: Trav’s Race Build: from B6 to Big Bore BP-Z3

Postby Scoota » Wed Apr 13, 2022 4:18 pm

StanTheMan wrote:also insure your bolts on the cam sprockets don't come undone.ever!!! fullstop!! its messy and expensive .

bent valves , and broken valve guides.... and little compression. LOL



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Re: Trav’s Race Build: from B6 to Big Bore BP-Z3

Postby Scoota » Thu Apr 14, 2022 12:22 am

Oh man, that’s a nightmare. I’m so sorry to hear that. I’ve been having second thoughts about fitting my eBay adjustable exhaust cam gear. You’ve pretty much talked me out of it. More tuning complexity, serious risk of failure, for possibly small gains. Not worth the risk?


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its worth thew risk to fit cam gears. I'll just never fit the cheap Fleabay ones ever again. Decent quality ones will give you the proper marks and take any guess work out of it but if you ƒü¢k up the timing on an interference engine its not going to be bad regardless of Fleabay cam gears or not.

good quality cam gears take the guess work out of it & will not fail

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Re: Trav’s Race Build: from B6 to Big Bore BP-Z3

Postby rascal » Thu Apr 14, 2022 9:06 am

Adjustable cam gears are definitely worth it, especially since you have aftermarket cams.

On my internally stock BP4W with just a smallish set of Warren Heath cams, the cam gears made a 20kw swing in power just by advancing inlet 4 deg & retarding exhaust 2 deg (or was it the other way? I forgot)

Such a small thing made a massive difference to power output, more than I ever would have thought, and if I hadn’t seen it with my own eyes, I would have called BS..

Dropping the cams in with cam gears at 0,0 it made 90kw, (up from 84 without cams) adjusting the 4deg/2deg the wrong way dropped power to 80kw, and then adjusting them the correct way made 101kw. A 21kw swing with no other changes, just moving the cam gears and running it up again.

So imo the question isn’t should you run cam gears, but should you run eBay ones or expensive brand name ones?

Fwiw, I ran eBay cam gears in my track car for 10years with no issues, and in fact still have an eBay exhaust cam gear on it now with the Rotrex. I did however change the little Allen bolts out for better ones for $10 worth at the bolt shop.

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Re: Trav’s Race Build: from B6 to Big Bore BP-Z3

Postby StanTheMan » Fri Apr 15, 2022 1:30 pm

yea i'm running something very close to that , like 3.5deg adv on intake & 2 deg retard on exhaust. but I would say its different with every cam.
Ive got 238 deg @ 050 and decent lift. 10.4mm I think.
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