48 IDA orientation.....

Doc Watson · 09-13-06, 12:18 PM

I just recieved my 4 x 48 IDA webers with a 'cobra' inlet manifold. Looking at various pictures of engines in the GT and the parts list in Legate's book, it looks like the webers should all be sitting facing the same way.

If you looked at the engine from the rear the right hand bank of webers have the fuel connection to the left side (between both rows of webers) and the left bank fuel connection is also on the left side. This means the fuel line should run through the middle of the webers, loops around the back and up the left side (still viewed from the rear of the engine).

The manifold has 'cobra' written on it in raised letters in the casting and there are two raised bosses, one central and one to the rear which are used to connect the linkage system for the webers.

Is this orientation correct for a GT MkI? also I think that original inlet manifolds had no bosses for the linkage and the letters 'FAV' on the front of the manifold. If i'm fitting a cold air box is it correct that the linkages are held in place by the bottom of the cold box?

Finally do you think it would be possible to use some 'aluminium filler' to replicate the 'FAV' letters? has anybody tried this? (the plan is to grind away the 'Cobra' letters and also the 2 bosses which held the linkage system.

BTW I will post a picture of the setup this evening to clarify. Oh and I also got a rather nice Aviaid pan for the soon to arrive engine will get some picks of that also.

And the big news is that at 6' 2 1/2" I had a chassis fitting last saturday and I officially 'fit' into a GT40 monocoque....... that was a tense entry into the car but I have ample leg room and with a Gurney bubble headroom is fine. If I didnt fit I was going to sell the chassis and move over to the dark side and build a P4.......

Oh and one final thing anbody know who make the phenolic spacers in the UK for the webers which helps prevent heat buildup in the carbs?

Doc Watson (officially a Jedi Knight now.......)

Doc Watson · 09-13-06, 02:13 PM

photos.........

Sandy · 09-13-06, 02:58 PM

Doc -

Check for leaks in the Aviaid pan as well as welding slag in the pickup (even after the coating they didn't see it). I have both problems with a pan and pick up from them. I am local and they fixed them but it was lame that the pickup got out the door.

Sandy

JimmyMac · 09-13-06, 03:00 PM

Doc,
The picture below shows the MKI - P1008 has the same configuration of Webers as your set up.
The spring-returns and rod linkages are fitted to the sides of the cold pan.

Doc Watson · 09-13-06, 04:36 PM

Sandy,

Thanks for the heads-up on the pan and pickup.... I will be inspecting and cleaning it this weekend.

Jimmymac,

Thanks for the picture, interesting to hear that the linkages are attached to the side of the cold pan, different to the MkIII parts listed in Legate which shows it attaches to the bottom plate of the cold pan.

So the linkage system is attached to the cold pan and not the inlet manifold.

This means I can go ahead and cut off my bosses to make the inlet more 'original looking' and also get rid of the snake logo on it.

Then I will consider the FAV mod (after a few tests)

I've just ordered a few parts for the IDA's and have attached a pdf showing the carb assembly.

For what its worth... parts 2 and 3 are M5 x 0.8 threads...... these are used to attached the air horn on the carb and also a top plate above the carbs.

Anybody help with the phenolic spacers?

Thanks in advance....

Doc Watson

JimmyMac · 09-13-06, 04:48 PM

Doc,
I personally would not bother with "grinding" down the bosses nor transfixing the FAV logo as they are out of sight when that cold pan is fixed.
Grinding may also distort your manifold.

There is also a full length actuating rod/throttle cable lever with small plumbers blocks fixed at each end to the bottom of the cold pan.
eBay has regular sales of phenolic spacers for your Webers.
Inglese' also sell them at reasonable cost.

I would also leave the purchase of the Weber actuator/linkage parts until I got the full cold pan design as these are non-standard.
For a good idea of the parts required please see the Racing Icons restoration site.

The key to any pull/pull throttle system is to make it bullet proof as your life could possibly depend upon it's efficiency.

Doc Watson · 09-13-06, 04:58 PM

Yes I agree that it wont be seen but I will know its there........lol...

I will check the casting and decide if the bosses will be removed... hacksaw and file job.... (I'm a time served fitter... well that was my first job) so I know my way around a lump of metal (i hope) it will then be externally sand blasted so it will have a uniform finish.

The plan will be to get the engine in the chassis with the rear clip on including rear window and then finalise the cold pan design. Then I can sort out the linkages as you said.

Will check ebay for the spacers....

thanks James

Andy

John Fitzpatrick · 09-13-06, 06:06 PM

I have an early Weber manifold which has two bosses on it, raised about 3/4". Casting letters say "FoMoCo". PN is C6AE0425-A, but I don't know if that's the one used by the GTs.
John

JimmyMac · 09-14-06, 06:56 AM

Here is another Cobra manifold with opposing Webers

Doc Watson · 09-14-06, 08:11 AM

Thanks for that James... seems you can get most flavours of orientation for the GT.... bosses are comming off tonight as is the snake logo.... also like your number plate SBF didnt cross my mind when searching for the V8 ### thing.

Regards

Andy

JCoop · 09-14-06, 08:49 AM

Andy, Ian Clark fabricated the turkey pan and set up the plumbing for me. I had a problem with the anti reversionary plate. It hit the glass when fitted. (something to consider when using the spacers too)

Doc Watson · 09-14-06, 10:27 AM

Ray.....

Yes I need to be careful with the spacers and room to the rear windscreen, with a replica mono chassis and original rear clip I should be ok.....(watch this space...)

Thats a nice setup you have..... where did you get the filters and what type are they?

I've seen them advertised but not sure which type to get.

Also it looks like you have replaced the top studs and nuts with brass bolts did the carbs arrive like this?

Regards

Andy Watson

JimmyMac · 09-14-06, 11:40 AM

Andy,
The fasteners used on original Bologna carbs were variable, some had studs with lock nuts and others zinc plated slot screws.
Both are available from Weber spares dealers.

Below is a pair of NOS Italian Webers with different fasteners

Doc Watson · 09-14-06, 12:32 PM

Again many thanks James for the information.

Andy Watson

JCoop · 09-14-06, 05:11 PM

>>Thats a nice setup you have..... where did you get the filters and what type are they?

I've seen them advertised but not sure which type to get.

Also it looks like you have replaced the top studs and nuts with brass bolts did the carbs arrive like this?<<

Thanks Andy. The filter I got from Inglese, slip-on type, $120 for the set. Redline also has them for a bit less money. Although they're in Cali, US post may be the way to ship to you.

http://www.redlineweber.com/html/for...ccessories.htm

The kit came like this from Topline and even included a set of tuning jets (4ea. of main, idle, and correctors),the synch meter, and a book. Then I sent the whole caboodle to Ian for the vacuum porting and plumbing.