Resucitar la carrera - Rebuilding the 1968

VW underneath a classic Italian body design.

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Piledriver
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Re: Resucitar la carrera - Rebuilding the 1968

Post by Piledriver » Wed Aug 03, 2016 11:33 pm

You can stiffen the horns up quite a bit by seam welding them, but they are often tweaked to begin with.
(Your previous motor easily made enough power to have done them in before it died with no brace)

I'm still looking at installing frame horns, but they are Berrien Buggy CrMo setup it will probably become one with the kafer brace and rear suspension, which is entirely removable/rubber mounted on a T3.
(and 68+ cars lack frame horns, to allow the real automatic trans)

Horns may bolt on for ease of dropping the motor/trans-- won't make that call until I start fabbing it.
It will be all triangulated so it won't matter they aren't welded.
CrMo tubing to make a brace seems to be in short supply around here, or I'm looking in the wrong places.
I might roll with the Tractor Supply setup again.
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RHough
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Re: Under Pressure - Balance this!

Post by RHough » Thu Aug 04, 2016 12:53 pm

RHough wrote:Just got the good news / bad news from the machine shop.

Crank and Flywheel spin up near perfect balance! ...

until they bolt on the pressure plate ...

There is enough slop in the pressure plate / flywheel location system (flange on flywheel fit to OD of pressure plate) that the assembly "wants to jump out of the balancer" ... FML out 6oz.

So ... what to do?

I told them to center it and dowel the plate to the flywheel ... if I ever have to replace the pressure plate I'll have to pull dowels and take my chances or pull the flywheel have the new plate/flywheel rebalanced ...

Life in the fast lane ...

What would Bob Hoover do? :-)
I got the crank back today. A couple of roll pins key the pressure plate to the flywheel and it came in nicely:

Before:
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After:
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Now have all the bits to get to the deck height stage. What are the chances that the same shims will give the right deck with a new crank and rods?

Deck height suggestions? 1.0 - 1.3mm? 1.0 mm is 9.25:1 CR 1.3 mm gives 8.98:1 CR
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RHough
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Good head?

Post by RHough » Thu Aug 04, 2016 3:34 pm

My heads don't have these air deflectors ...

Do I make new ones or leave them off?
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Re: Resucitar la carrera - Rebuilding the 1968

Post by FJCamper » Thu Aug 04, 2016 4:07 pm

Hi Randy,

VW's purpose for these little deflectors was to divert air left and right through the grooves between the fins and they were intended to assist the small, spring-clipped air deflector. Somehow they vanished with OEM VW heads.

I know of no special problems in leaving them out, and if anyone can make the case we should have them, we'll use them.

FJC

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Re: Resucitar la carrera - Rebuilding the 1968

Post by ONEBADBUG » Thu Aug 04, 2016 8:15 pm

To me, it's well worth the effort to make these up and install them. Along with drilling through any flashing that blocks air flow, the air has to go where it's needed, not just anywhere. You can imagine the air in the center of the head where it's cool, is not doing anything, it's a leak. Those dealies divert it to the hot part of the head.

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Re: Resucitar la carrera - Rebuilding the 1968

Post by RHough » Thu Aug 04, 2016 8:35 pm

FJCamper wrote:Hi Randy,

VW's purpose for these little deflectors was to divert air left and right through the grooves between the fins and they were intended to assist the small, spring-clipped air deflector. Somehow they vanished with OEM VW heads.

I know of no special problems in leaving them out, and if anyone can make the case we should have them, we'll use them.

FJC
Bob Hoover:
One of the most critical parts on VW heads is the small air-dam located on the underside of the head between the combustion chambers. Without this air-dam in place most of the cooling air reaching the heads is lost. With the air-dam in place, the gush of cooling air is obstructed and directed to either side, bathing the underside of the combustion chambers. When the cooling air is slowed down in this manner two things happen. The air picks up more heat since it is in contact with the heads for a longer period of time. The second – and more important thing – is that the pressure of the cooling air above the heads will rise.

Didja get that? The cooling air pressure goes up with the air-dams in place.

It is that subtle increase in pressure that allows the cooling air to be forced toward the corners of the heads, out toward the exhaust valves – the hottest parts of the engine, where it is needed most.

From this blog entry: http://bobhooversblog.blogspot.ca/2006/ ... ffles.html

The theory is the same as the cylinder air diverter. I read somewhere that the cylinder fins only handle 17% of the cooling, the heads and oil do the rest. I have not found a rant from any builder that shows data on cylinder head temperature distribution with and without the deflectors.

I suspect the reason that new OEM heads don't have them is the new heads are those used in the low compression and EFI engines for the Mexican and South American markets? Easy enough to fabricate so I did some. Then I notices how VW held them in place, so I'm going to make another set with the little bend to fit tabs that wedge between the fins ... I'll wire them in too ... just because.

Not that Bob Hoover is a god or anything ... but who else has an OEM part names after them? "The Hoover Bit" he does seem to pay attention to detail ...

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A CSP air box is how much? Trailer Trash option...

Post by RHough » Thu Aug 04, 2016 9:01 pm

One of the goals with the new build is noise reduction.
Exhaust
Mechanical
Intake

Alloy pushrods to replace the steel ones should quiet that clatter, and the alloy valve covers should further reduce the valve train noise.

How about a quiet intake?
AirBox.jpg
Great, does it fit a Ghia? No and it's 900 Euros! Gag ...

My yet untried trailer trash solution starts with a pressure hat from CB. These fit the Weber IDF air filter bases and at least aim the intake at the back of the car about a foot farther from the firewall and passenger compartment. They are for blow through turbo installs. The inlet is 2" OD pipe.
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Pretty cool! I'll just toss filters on the ends and call it good ...
Hmmm ... not many choices for 2" flange mount filters from K&N or anyone else ... The filter area is at the lower end of what K&N recommends for the engine using 60 CID and 7000 RPM.

It's a VW right? K&N has a VW Solex adapter that fits a 2 1/32" carb that fits a 3" flange filter! and it's chrome so therefor faster! Lower ET, more HP!
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This opens up the filter choices to something with almost the same area as the ones that fit the IDF filter assembly! There should be enough room on both sides for these and I have the option of trimming the intake tubes if they are too long.
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Cheap Thrills Engineering!

A side note about K&N and your local parts store. Local guy I like to support did not know about the adapter, said he could order filters he doesn't stock, but it would be 2-3 weeks and if they are wrong there are no returns on SO items ... normal stuff. So I went online, found the adapters and filters ... free 2 day international FedEx on orders over $20 ... had them in 48 hours.

Wow!
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Ian Godfrey
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Re: Resucitar la carrera - Rebuilding the 1968

Post by Ian Godfrey » Thu Aug 04, 2016 11:14 pm

Awsome powder coat has all the cooling bits including the tin that clips in under the head
http://www.awesomepowdercoat.com/Cylind ... ctors.html

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RHough
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Re: Resucitar la carrera - Rebuilding the 1968

Post by RHough » Fri Aug 05, 2016 12:12 am

Ian Godfrey wrote:Awsome powder coat has all the cooling bits including the tin that clips in under the head
http://www.awesomepowdercoat.com/Cylind ... ctors.html
Wow! Thanks! I had forgotten about them!

Might have to see how fast I can get stuff from them ... I'm up against a deadline ...

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Re: Resucitar la carrera - Rebuilding the 1968

Post by RHough » Wed Aug 10, 2016 10:09 pm

Big thanks to:
Mario - The Dub Shop for having the EFI Kit ready yesterday
Clark - Awesome Powdercoat - for expediting the little tin bits for the heads and cylinder tins and drop shipping to Mario
Mike - House of Ghia - for getting some t-stat bits (bracket and link arm) that I was missing and drop shipping to Mario

I have the lower end together with no drama except deck height. 0.7mm (0.0275") is a bit tight. The shims are 0.057" so I'm going with 0.090" to give me a safe 1.5mm (0.060") deck.

The wrist pin clips are loose and were moving in the pistons. CIP didn't have spirolocks so I'm going with teflon buttons.

Once that's done I can finish the aluminum pushrods 0.030" longer than the steel ones that I took out and I should be good to go ... just have to wire and plumb the EFI ... piece of cake ... right?

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Re: Resucitar la carrera - Rebuilding the 1968

Post by Piledriver » Wed Aug 10, 2016 11:32 pm

Aluminum buttons weigh a lot less.
.060 deck is the top end where squish does anything useful, I'd try for .050 or less.

I ran ~ .023 for ~150K miles, but obeying stock redline.
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Re: Resucitar la carrera - Rebuilding the 1968

Post by RHough » Thu Aug 11, 2016 11:58 pm

Piledriver wrote:Aluminum buttons weigh a lot less.
.060 deck is the top end where squish does anything useful, I'd try for .050 or less.

I ran ~ .023 for ~150K miles, but obeying stock redline.
And there's the rub. From the carbon patterns on #3 & #1 it looks like I had 0.00 deck at 6300+ granted something was not right since the same assembled deck was fine on #2 & #4.

However - I'm going to set the redline at 6500 with the same AA pistons. I don't know how much power or economy I might lose with a 1.4-1.5mm deck and a loose squish area. I do know that I'd lose sleep with worry if I leave the deck at 0.7mm.

Available shims are 0.020 - 0.030 - 0.040 - 0.060 - 0.090 - so since I want to drive it next week I;m picking up the 90's. I'measure the deck on final assembly and figure what the shim needs to be for a 1.1-1.2mm deck and have set made to specs for my winter inspection/tear down.

I made up the mounts for the Accusump and the Oil Tank today. Got the dry sump pump cover / pulley / VR sensor / pulley tin fitted.

Did the install on the inner deflectors then had to trim them to fit the heads with the IDF manifolds in place. Popped the lower head deflectors in after finding the casting flash made it impossible for the t-stat rod to pass through ...

Been reading and playing with Tuner Studio to get a feel for what's there.

Long days of test fit, remove, modify, repeat ...

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Re: Resucitar la carrera - Rebuilding the 1968

Post by Piledriver » Fri Aug 12, 2016 12:06 am

EDIT:
Having clean areas does not mean zero clearance, the carbon simply doesn't build up there with a reasonably tight deck.

My current motor is running .055 which is far larger than I prefer, still had a perfect mirror image clean pattern when I had the heads off for a clean up/reseal early on, and it never sees over 6K. (With a Web 73 there is no point, also well enforced by the rev limits in the EMS)
******************8
Clean up the casting flash, I've seen heads that had almost no airflow in places, particularly around the exhaust ports.
Jake Raby once said it didn't matter, but one specific head I had was trash, full of cracks, while the 3/4 side head of the same EFI core engine with very little flash was ~perfect.
(I had a decent history on that core engine from the PO, he had owned the car it came out of since 1973 (was a 71 411) was parked on and off for decades because EFI and no one capable of working it back then, even though D/LJet are trivial to troubleshoot, you had to read and comprehend, skills few US auto mechanics apparently possessed in the 70s and 80s...)

Most better hardware stores sell ~foot long 1/8" "aircraft" drill bits and sawzall blades.
Only takes a few minutes.
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Re: Resucitar la carrera - Rebuilding the 1968

Post by RHough » Fri Aug 12, 2016 11:35 pm

Tin and in tomorrow!

Fabbed the Accusump mounts and the oil tank mounts. 6 new holes ...

Final assembly with the skinny deck ... we'll see. Crank trigger, cam sync, fuel pump blocked off ... no turning back ...
EFI or bust! Fire Tuesday? Wash and tune Wed - Thurs and make the street drags Friday night? Gonna try.
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Re: Resucitar la carrera - Rebuilding the 1968

Post by RHough » Sun Aug 14, 2016 10:21 pm

Just put on the tin and install the engine ... right ...

Aftermarket Heads did not have the deflectors
Aftermarket Tin did not have the deflectors

Awesome powdercoat to the rescue!

Fitting the inner deflectors was a chore. When the tin is reformed (bent) to clear the manifolds the profile is no longer the same as the deflectors. After fitting and trimming they fit with the manifolds in place. Thought that was the end of that ...

After installing the tin and having to massage the fit here and there we put the fan shroud on and ... it didn't fit. Turned out the just installed inner deflectors angle up due to the manifolds and they hit the t-stat vanes. When you install the deflectors you have to make sure the top of the deflector is the same height as the fin on the cylinder. The vanes will clear and the t-stat will work ...

We got 'er done and the engine went back in! We mounted the intake system so we could can lay out the coils and IAC valve & plumbing. The plug wire guides work to keep sensor harnesses tidy ...

The Intake air box / filter combo fits too!
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