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Old 15-05-2015, 08:05 PM   #21
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Nothing much to post but lot's happening behind the scenes.
James Calvert has sourced suitable rods from the states and these will be Scat I beams which he will then machine to take the required 24mm pins.
The supplied bolts will be chucked for some genuine arp bolts, so this sorts the weak point that was preventing any possible revs above 6k.
JC suggested a web 86a grind cam for my requirement of street use only, mid range torque for normal driving but a red line around 6500rpm.
The other limit was .500' max valve lift as any modifications required to gain clearances gets expensive fast.
WBX's have a fixed deck height as the water jackets also seal against the head, meaning you cannot use spacers under the barrels like a t1 engine.
In order to gain deck height you would have to shave the piston tops or start looking at alternative conrod/piston combos.
I'm not made of money and the cost of this build is rapidly heading towards 2k anyway
This cam matched with 1.4 rockers lands perfectly just under .500' but their use will depend on spring requirements which I will discuss later.
Lifters remains undecided between T4 solids or gutted and spaced T25 units, the later having both better oiling and less weight, but as I have an almost complete set of new T25 lifters i'll probably go with them.
The modification requires removing the internal piston and replacing with a suitable length tube that fits snugly under the snap rings which is apparently something Jim at TES used to do and may still have parts for.
JC is trying to source some German quality valves as stainless is proving difficult to find due to the 9mm stem.

And now to my mistake and the consequences

During the port work I noticed some small bumps in the inlet chamber which appeared to serve no purpose and where duly smoothed out.

Turns out this area is pretty close to the valve spring seats and by doing this I will no longer be able to machine the seats down for fear of breaking through.
The other unexpected thing is that according to someone who races these engines they actually improve air flow due to the rolling effect created prior to hitting the bottom of the port turn.
Luckily machining should not be required as an option is using Berg retainers which increase the valve gap by sitting further up the stems.
The upshot may mean 1.4 lifters won't have any suitable springs, but I will leave this to the experience of JC.
Push rod's also remains undecided between JC's hd aluminum ones and stock.
The reason aluminum was used in T1 engines over steel was to match expansions as things got hot retaining your valve gap.
On a T25 wbx engine steel was used as it provided the extra required strength for dual valve springs and the raised rev limit.
Expansion is less of a problem on a wbx engine as the temps are so much better regulated, so you would not expect any tapping when using solid lifters on a hot engine.
The down side of the steel push rod's is of course weight but I think cost may be the deciding factor.
In anticipation of setting valve geometry I thought I would make an adjustable push rod out of an old used one.

Just needed to tap the holes and cut down a suitable bolt.

Had the tap in the tool box, so it cost nothing

Build wise i'm looking at receiving parts for the bottom end mid december so until then i'm focusing on the gearbox replacement and replacing all the suspension bushes whilst it's all apart.

The replacement alternator bushes arrived.



Despite being made in Germany they lack the quality of the original and were difficult to fit due to the holes not aligning perfectly
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Old 15-05-2015, 08:06 PM   #22
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A little more progress.
I'm still waiting for the main engine parts from JC but I suspect it will be next year now.
In the mean time I've been preparing what I can.
First up is the carb linkage setup.
This has been a pain in the ass since day one as it's not ideal for this engine layout.
I've been through 2 sets of bar mounts ends having worn them down to the point of engine running issues.
Part of the problem is that the bar is at such an odd angle.
The solution is to fit a CSP bell crank which will also free up room around the air filter.

Once it arrives there may be some tweaking required as it's a T1 style and I need to clear both the alternator and cooling hoses.

Second job involves the lifters as i've decided to modify my existing hydro lifters rather than go solid T4's.
Having discussed at length various options with a chap on shoptalk i'm going with his suggestion.
Basically all that needs doing is replacing the bottom spring with a solid sleeve, so I purchased a suitable steel rod that's very close to the bore diameter which I can cut down.

This is a hydro lifter with all it's components.



A hydro lifter works by filling the bottom area under the main piston with oil taking up any slack in the drive train.
There is a little ball bearing at the bottom of the piston that allows oil to pass though as required.
The lifter can adjust just under 5mm of gap so this will be the required sleeve depth.
You must retain the existing piston setup as it regulates the oil flow to the pushrod.


Each sleeve is cut and then required sanding to get as close to 4.7mm with the basic tools at my disposal

First hydro is back together with the retainer nice and snug to ensure everything stays put.

I'm debating whether to purchase a set of later style circlips as i'm concerned the current retainers won't hold up to 6k + revs.

Just got 7 more to cut, file, sand, measure, sand, file, measure........
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Old 15-05-2015, 08:06 PM   #23
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The bell crank arrived and as expected it's not a direct fit
On the wbx engine the top case has more meat where the studs fit.
This means the crank mount won't fit, so I made a bracket to relocate things.

I also had to replace the supplied mount stud with a longer suitable bolt and lock nut to stop the mount twisting back during operation.
Unfortunately the mount is not central now meaning the rods create uneven carb linkage movement, so I will be adding a spacer on the bracket.
This will mean the support bolt will then sit over the case webbing, so more mods required here also.
Nothing is ever easy with this engine
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Old 15-05-2015, 08:07 PM   #24
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Road trip today to pickup parts from JC.
The crank has been balanced and polished.

Trust me, it's done, but I will leave it sealed up until ready for the initial build check.
The Scat rods have been machined and honed for 24mm pins.


Also they have been re-balanced and fitted with genuine arp 2000 bolts.
Thought I would weigh them for a comparison to stock:

Stock unit blows the scales as they max out over 660 grams, so total 671 grams when weighed in bits.


Scat comes in at 554.7 grams so that's 116 grams lighter or nearly 18% lighter!

I went for the lightened 200mm T4 flywheel combined with a 1700 lb Kennedy pressure plate and Diakin friction plate.

The flywheel has been balanced and marked to indicate component positions when assembled.


These flywheel's come pre drilled for extra dowel pins but won't be required for this build.
JC went through some more Cam / lifter combo's but the limiting factor of 500' max lift only left the original web 86a matched to 1.4's option.
This is actually a good choice anyway as a lower lobe height is better for the valve train but it does add considerable cost when including a replacement set of 1.4 rockers for my 1.2's.
Lifter wise I'm still torn between my converted hydro lifters and a set of JC's lightweight T4 units.
JC's view was that a T25 lifter had a much higher chance of wiping a lobe based on his experiences.
Luckily I don't have to make this decision yet until the valve geometry needs to be set.

This brings things to the last hurdle, valves.
JC has had no luck sourcing a quality set, so i'm going to have to try myself.
It does look like custom made may be my only alternative.
I'm keen to find out what the wbx racers use as this would seem a good place to start, so will be posting on STF and emailing a couple of wbx builders.
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Old 15-05-2015, 08:08 PM   #25
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Slow progress but things are happening.

The heads have been completed by JC.
After much searching I ended up buying a new set of TRW valves only to find out that Manley offer an affordable custom valve build in stainless
There where concerns that the head seats would not take a satisfactory 3 angle job but JC was able to.
To further frustrate matters there are issues with spring heights due to the odd WBX setup.
Up shot is that despite a lift of 500' being plausible the lack of spring travel makes bind a higher risk.
JC has played around with several retainers, both aftermarket and stock, but not been able to get the travel required.
In the end stock T1 combined with his single springs provided the best compromise, but he advises to run 1.25 rockers rather than 1.4 as it's too close to call with 1.4's varying sometimes upwards. Bugger

Anyway, moving onto more pressing matters.
In order to check rod/camshaft clearances and backlash I needed a suitable stand.
Building an engine in your living room is great for cleanliness but not ideal for engine stands
With that in mind I knocked up this:





The wood used was just hanging around as it's warped, but it's sturdy enough.
I knew all those woodwork classes at school would pay dividends, my teacher would be proud
Once all the parts arrive from JC I can begin building the bottom end.
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Old 15-05-2015, 08:10 PM   #26
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My new Torque Wrench arrived yesterday

NOS for a good price but being the 70 to 350nm one it's no use for most of the engine build other than the rod bolts and flywheel bolts.
I have an old skool style wrench for everything else.
It will, however, be very useful for heavy duty stuff like hub nuts and suspension bolts!

The conrod bolts are 12 point imperial requiring the purchase of a snap on socket.

Torquing to 50 lb/ft was a doddle on my new engine stand

The bolts have been through 3 torque cycles as instructed but I may do another this time checking the stretch despite these being new.
For now the crank and rods are packaged up to keep things clean.
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Old 15-05-2015, 08:10 PM   #27
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Couple of engine checks this afternoon.

1. Cam backlash.

This is a little academic as you have very little options available due to the fact aftermarket cam wheels are all the same spec
The only options in the face of out of tolerance specs are try another and hope, try another crank drive and hope or chuck them both and go straight cut
Actually I lie as if you had access to a bunch of scrap stock cams you could drill the rivets on one that has a suitable offset and get it machined to work on the aftermarket cam.
With this in mind many body parts where crossed....



Although this camshaft won't actually be used the wheel will be, hopefully.
To get an accurate reading of lash you first rotate the crank in the normal direction a couple of times to mesh things properly and with the crank held in place rock the cam wheel.
If you hear CLUNK CLUNK all is not well as there should be minimal movement.
On mine I get no rock at all, which is either very bad or actually great.
The allowable lash range is .000" to .002" which will allow for expansion when at running temps, but how do you know it's really .000" and not just binding?
To confirm this you rotate the crank backwards a couple of times and check again, but if the cam wheel lifts right out of the case it's binding and you're in trouble.
I actually get some lash which measures an estimated .003" as my gauge only reads in increments of .01".

Upshot is that this wheel looks fine, so happy days

2. Conrod side clearances.

The VW manual states upper wear limit is .028" with no lower limit mentioned.



All 4 check out with a range of .012 to 0.15".
As a side note it's interesting to see the original vw drilled holes for balancing along side further material removed when re-balanced.

Not much more to do until the remaining parts arrive and are checked, so things may be quiet for a while.
Thanks for reading.
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Old 15-05-2015, 08:11 PM   #28
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Phoned JC today after received an email during the week that detailed the final bill and also that the cam selection was out of stock due mid May.
I nearly fell off my chair when I saw mid May as this would mean the bug would completely miss summer and in all likelihood require running in over winter:ticking:
Anyway after a quick discussion I decided to go with the next cam up in the range, the web 86b.
What this cam will offer is more high end rev scope should I want more HP in the future as it will be a simple case of bigger carbs
Going 1.25 ratio with this cam actually increases the lift from .468" on the 86a with 1.4's to .479".
Sounds like the right choice in the first place actually.

On a different tangent one thing that has been bugging me is the WBX oil dipstick setup.
It's stock position interferes with the boot lid so I previously modified it to sit further round, but it's hard to pull out and I actually snapped the one I have whilst trying to make it straighter.
After a brainwave I wondered if a T1 would fit?

Nice Jim at the engine shop donated a spare one and also a spacer tube.
Although the spacer pipe needs cutting down it's a nice fit and the dipstick does sit low enough to take a reading.
The issue is going to be whether the cooling pipe gets in the way or not, so once the heads are back I will mock up the pipes again and check.
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Old 15-05-2015, 08:12 PM   #29
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Parcel arrived Tuesday



Empi 1.25 Rockers, hopefully something quality from Empi.

Looks like the shaft shims will need some tweaking.
Sadly this rocker set does not have any lash caps but I have some used ones that will allow me to set the rocker geometry.

Lightweight lifters.


These are 90 grams which compares very well against my 125 gram converted hydro lifters.
Note the little holes that will lube the camshaft lobes.
Much like the T25 hydro units they also have better oiling due to the single large groove rather than the T1 style of 2 grooves.
As I understand it this will provide oil pressure through to the rockers all the time unlike T1 which only works when the lifter is in line with the smaller groove.
A common mod on T1 lifters is to cut a slot between the grooves.


Camshaft looks good but will get a complete check.

Should liven up this engine

The heads are all sealed up having been cleaned, but the valve setup looks good.
I plan to check the head cc's now all the head work is done and made a suitable bore cover by grinding down an old CD to fit. I have a pipette kicking around from my old Bio diesel making kit that I can use with some gearbox oil.


Lot's of checking and measuring ahead....
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Old 15-05-2015, 08:13 PM   #30
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Camshaft has been switched over, no drama's there
Due to the cam lift being so much more than stock it was worth checking the lift bore clearance although as i'm not running T1 style tappets you don't really have an issue to start with.

I don't have a picture but the cam lobe does get close to the crank in one place so this cam would be an issue if the crank had a longer throw than the stock 76mm.
A quick lobe check was performed:

#
#=1=2=3=4=
#

1. 378'
2. 374'
3. 375'
4. 377'

Cam card states 575' on a 1.5 rocker for both inlet and exhaust which is 383' on the lobe, so a bit under spec but consistent enough.
With my 1.25 I should be getting around 472' although JC say's you usually get more than 1.25, so will be interesting to check when doing the geometry.

Next is to check for valve to piston clearance.
I went well below the advised 500' with this camshaft/rocker combo so there should be no worries , but I would be a fool not to check.
JC states 80' - 100' clearance is required.
With the crank/cam installed correctly meshed the case was closed secured with a couple of nuts.
Next a piston/liner was installed without rings.
The other rod end was protected with some paper and tape to prevent it from knocking about inside the other empty liner.
Two lifters where dropped in followed by pushrods.
A thin layer of playdoh was added to the piston crown where the valve pockets are.
The head was lightly bolted down and includes a couple of used compression rings to get the correct deck height.

The rockers where adjusted to have zero clearance and the engine was turned over a few times.
Took the head off and the playdoh was completely untouched, so a thicker layer was added and a test impression was also made in the middle.
Head back on, more revolutions and head off again.

Great, there is plenty of clearance as the valves don't even get close

Last thing done was a bit more work on the heads to better balance the chambers.
First I re-tested all 4 chambers to confirm that 18.5cc is the upper target.
After some more work with the dremel I have 1 & 2 @ 18.5cc and 3 & 4 @ 18cc which will have to do as I have run out of sanding media.

Next job is checking the camshaft timing which is going to be interesting without a degree pulley wheel
Going to need to get creative for this one.

I guess this thread is primarily an aide-mémoire to ensure I don't miss anything and for recording results.
I've had to trawl through so many web based guides to get to this point not to mention help from various individuals.
Trying to choose the correct parts has been a nightmare with so many conflicting views on what's tried and tested against what looks good on paper, not to mention the lack of suitable performance parts!
I knew this engine was going to be trouble to modify and so far i've not been disappointed
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