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Many thanks to all the guys who helped on here to make this possible.

Spec:

2.1 DJ engine.
Fully balanced bottom end.
Weight matched pistons/pins.
Scat I beams, small ends machined to 24mm, ARP 2000 bolts.
OEM Liners and High compression pistons.
AMC Heads, ported, 3 angle job, TRW valves and Stateside HD single coil springs.
Web 86B camshaft.
Stateside Lightened solid lifters.
Stock pushrods.
1.25 rockers (porsche style adjusters).
Ported CSP manifolds topped with Dellorto 48's.
Lightened forged 200mm flywheel.
Kennedy Stage 1 clutch with daikin friction pad.

Will be running a Turbo Thomas side exit exhaust system.

Looking forward to getting it running in the bug

That is one nice waterboxer

That is one nice waterboxer

Lookin' good sir.

Thanks guys

For those interested I did a build thread.

http://www.volkshub.com/thehub/showthre ... gine-build

nice work,
browsed quickly through your build thread. and did not see you check cam lobe vs lifter compability?
if the cam rides on the edge og lifter du to the small diameter lifter.
which will lead to qick cam/lifter failure if not correct.
this may also be the case of your previuos cam lifter failure.
my experience is that theres not many cams that work with the smal diameter lifters, so big foot type4 lifters or convert to type 1 is the solution.

I am also concerned if an 86b is compatible with t4 lifters unless you had a custom one specifically ground with the T4 profile. (Webcam would be able to say if that was needed though)
It is a fairly mild OEM based profile, Duntov designed for early Corvette IIRC.

Not compatible with single springs if T4 profile, esp considering the heavier/longer WBX valves and RPM capability.
WBX had pretty HD dual springs from the factory for good reason, with a ~web 86 ish profile stock.
(closest off the shelf aftermarket cam to what MV/DJs came with, at least timing wise)

The build looks awesome, don't want to be a downer, but these issues are valid concerns.

Regarding the lifter/cam combo, the specialist who has been doing the machine work states the 86A and 86B as compatible with the lifter he supplied, but the 86C needs the T1 style wide lifter as has been mentioned.
Now that I have checked, the T1 web 86b is different to a T4 web 86b so I may have a problem
The springs are custom made and designed to operate at high rev ranges with the required pressure.
These replaced the existing dual setup as they could not hold enough pressure for the setup i'm running.

Best I speak to the supplier to see where I stand but i'm pissed to find this out now the case is together

Thanks for the advice guys.

Now that I have checked, the T1 web 86b is different to a T4 web 86b

If what you mean is that they have different p/n, of course they do, the T4 uses a totally different and non-compatible cam blank, the same grinds for T1 and T4 are always different p/n.

Nice build, though, that oughta scream.

If what you mean is that they have different p/n, of course they do, the T4 uses a totally different and non-compatible cam blank, the same grinds for T1 and T4 are always different p/n.

I mean the actual profile appears different, if you believe the cam cards that is.

T1 - http://www.webcamshafts.com/pages/autom ... 02752.html
T4 - http://www.webcamshafts.com/pages/autom ... 00786.html

Looks like the intake has an extra 12 degrees on the T1 grind.
I guess the max of 300 degrees make it critical on the lifter edge.
With this in mind I have purchased a bore scope and plan to investigate more closely.
The overall consensus is that this combo should work but I will not proceed any further until I'm sure it's ok.

Feel pretty foolish for not checking this having tried to be thorough during the build, but no damage done except to my pride and perhaps my wallet

Nice build, though, that oughta scream.

I bloody hope so, it's cost a small fortune and many many hours to get to this point!

Although a T4 guru this guy's been a real help.
http://www.statesidetuning.co.uk/

Based on the cam card info, with rocker ratio compensated for (cam lift only) they appear ~identical.
T4 nominal cam lift is 1.3:1, the T1 web86#s appear to be using 1.5:1 rockers.
The opening/closing times are identical as is lift when subtracting rocker ratio.

There's more to it than that, but if your engine builder says its a known working combo he has used before, I would not sweat it much.
I would still love to see the borescope video shots if you can manage it.

Stateside Tuning has a great reputation.
I would still like to hear it was "blessed" for WBX by Webcam, they only list a stock grind or regrinds for WBX.

JC @ Stateside shows on his website that the web 86a/b work with the smaller lifter for T4 builds, but the 86C requires the larger T1 lifter conversion.
Certainly during the various discussions and subsequent purchase no mention was made regarding any compatibility issues, so I took that as read.
I doubt Webcam would really want to get involved with WBX approved parts as it's a niche market IMO, but if they confirm the T4 / web 86b combo it would amount to the same thing.
I will certainly be posting bore scope videos, just for shits and giggles

Done some more research.
From the Web Cam site:

86b
Designed for large displacement racing engines. Works well in a off-road application. Great torque! WEB CAM mechanical lifters required. See part #00-265.

For the 86C they also recommend the same lifter so I would say JC @ stateside errs on the cautious side.
Looks like this combo should be ok, but still going to check as best I can.

The factory knew the DJ cam was at the limit of lifter edge life, lobe chamfers are key even with T1 lifter conversions, at the very least they should be whetstone worked, preferable die grinder stoned to a chamfer sizing as seen in the pic. I got away with some hairy cams back in the day as then they were often ground small base circle on used cams, modern blanks are bigger base circled and need all the help they can get even on T1 conversion lifters with heavy dual springs.

I did look at lobe chamfering as a mod but was too concerned about making a hack job of it.
Upon reflection it would have been a sensible thing to undertake.