ZF Easy In & Out Modification

I wanted to be able to slide the ZF out of my CAV while leaving the bellhousing, engine and starter in place. For those of you who have been there, you know that the ZF gets five allen head bolts securing it to the bellhousing from the outside, but it is the two additional allen heads that have to be installed from inside the bellhousing while the ZF is on the floor that pose the nightmare for removal and installation. Apparently everyone swings the engine and trans in as a unit, or pulls it all to service a clutch.

After a few teathing problems and false starts hear are the finished modifications for pulling just the ZF.
 
The bellhousing is machined to gain access from outside of the bellhousing to the area where the two top allen head bolts were installed from the inside while the housing and ZF were on the floor.
 

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Changing perspective to the ZF and bellhousing on the floor...the slot for the passanger side shows the stud that now is in place instead of the allen head bolt.
 

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Looking at the same area from inside the bellhousing.
 

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A further close-up shows that the only machining work came straight down from above to give access to the area. The ZF has not been modified, and the shadow of the 10mm allen bolt seating area shows no change to the bellhousing surfaces or thickness.
 

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We made the stud to fit the 10mm x 1.5 thread in the ZF, but we made the other end a 3/8 x 24 fine thread. The small head (7/16) of the self locking jet net allows me to use a 7/16 small ratchet box wrench with 4 clicks per throw inside the machined slots, and it clears the headers easily. You can see that the washer has been slipped in place onto the stud. The stud size was calculated to bottom in the ZF, and leave two threads out after the jet nut is seated. The jet nut and stud area are slightly less than the size of the head on the allen bolt they replace.
 

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Re: ZF Easy In & Out Modification

Things look tight, but they are really easy. If you drop the nut it takes ten seconds to swing the ZF out, grab the nut, and ten more to line up the studs and try again.
 

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Lots of room...no problem maaan!

Enjoy,
Buzz
 

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Steve:

I plan too, but that's like cleaning up the kitchen after the meal. I just finished up this much this afternoon.

Regards,
Buzz
 

Tim Kay

Lifetime Supporter
Buzz,

I hope your wife knows you put this much thought into her Xmas gift each year /ubbthreads/images/graemlins/wink.gif
 

Pat Buckley

GT40s Supporter
Thanks for the neat idea.

Here is an idea to consider - it comes from those days when I raced a car (Lola FC with a Cosworth BDJ) that was so crowded around the front of the engine that I could not get a timing light in there. The solution was to slot the bell housing so that I could time the engine off the flywheel... do you think this is needed on a GT?

I am about to install the engine for the first time on my CAV so I do not know what access is like in that area.
 
Re: ZF Easy In & Out Modification

[ QUOTE ]
slot the bell housing so that I could time the engine off the flywheel... do you think this is needed on a GT?

[/ QUOTE ]

Just remove the wall (panel? What's that thing called) behind the seats, and the flywheel is right there. I could also reach the distributor on mine through the opening (289 - might be harder if you had a 351 block or Getrag transaxle, as it would be up higher...).
 
David: I'll take it that your 'pirating' is flatery of the mind. (That's your flatery of my mind.) Enjoy!

Tim: I have never been able to live with only one car in my life, even though I have intimately known a 206 Dino, a twin turbo NSX, and the CAV GT40. I am sure it is a character flaw. That same apparant flaw carried over to my life with wonderful woman. I never got married...so no wife to consider when expending time, energy, and mula on the '40. But the GT40 and beautiful woman go well together, so I'll continue to try to carry the flame.

Pat: I agree with Steve. Easy access for timing behind the seats. That part about Steve having a flywheel behind the seats has me a bit confused I must say. That's a performance option I haven't considered.

Regards,
Buzz
 
[ QUOTE ]
That part about Steve having a flywheel behind the seats has me a bit confused I must say. That's a performance option I haven't considered.

[/ QUOTE ]

Huh? What do you mean I put my engine in backwards? /ubbthreads/images/graemlins/tongue.gif

I had to get up early this morning. I don't think my brain was functioning properly when I wrote that. /ubbthreads/images/graemlins/smile.gif
 

Howard Jones

Supporter
On our GTD/Renault cars it is very easy to mark a spot on the flywheel thru a opening in the bellhousing to use as a timming mark.

After you have done all the tuning on the car and are happy with the static timing, lets say you like 13 degrees BTDC, you can line up the static 13 degrees timing mark with the timing pointer when the engine is on TDC of the compression stroke of #1 cylinder . Then make two marks, one on the bell housing and the other on the flywheel in line with each other.

You now have transfered the 13BTDC mark to a place that you can put a timming light on with out taking anything apart.

Good for a quick check of the static timming.
 
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