Wondering if anyone knows if a set of IDA Webers will fit w/o interfering with the rear glass on an early CAV. I know it may depend on the specific manifold and the height of the external venturis... The engine is a crate 302 (presently with Holley 650). Anyone have any experience with an early CAV, a 302 and Webers? Also, any ideas on the topic of add'l hp this may generate? I'm guessing maybe 20hp over the Holley 650. Thanks in advance!
CAV and Webers....
- Thread starter CliffBeer
- Start date
Pat Buckley
GT40s Supporter
They work on my car with a ZF trans.....I don't know how much higher the engine sits with other transmissions.
Hi Cliff
You may not be able to use the backfire plate or air cleaners on Webers in a CAV with the Audi/Getrag transaxle. The reason has to do with the increased height of the engine due to the location of the input shaft to the transaxle being above the differential, rather than below as in the ZF application.
Your stock 302 on Webers will probably not hurt a Getrag if driven carefully. For more poke and choice of ratios, seriously think about going to a ZF. New boxes are available and our retro fit ZF kit will be available soon.
The ZF kit will include the transaxle mounting bracket (CAD drawing attached), dedicated bell housing casting, motor plate for starter location, motor mounts for pre s/n 100 CAVs and complete shift rod mechanism. Price TBA but this is going to make the upgrade simple - something we all need in the land of '40 LOL.
You may not be able to use the backfire plate or air cleaners on Webers in a CAV with the Audi/Getrag transaxle. The reason has to do with the increased height of the engine due to the location of the input shaft to the transaxle being above the differential, rather than below as in the ZF application.
Your stock 302 on Webers will probably not hurt a Getrag if driven carefully. For more poke and choice of ratios, seriously think about going to a ZF. New boxes are available and our retro fit ZF kit will be available soon.
The ZF kit will include the transaxle mounting bracket (CAD drawing attached), dedicated bell housing casting, motor plate for starter location, motor mounts for pre s/n 100 CAVs and complete shift rod mechanism. Price TBA but this is going to make the upgrade simple - something we all need in the land of '40 LOL.
Attachments
Canuk40 said:
Hi Ian, thanks, that's very helpful. I'm about to purchase an early CAV with the getrag/audi unit - a fine combination generally. However, as you suggest, I would be interested in a switch to the ZF unit when your conversion kit is available for the dual purpose of a) perhaps being able to lower the engine somewhat to get Webers in there, and b) handle a little more hp. I realize the ZF unit is much more expensive. Your kit looks/sounds great by the way! Please do let everyone know when you have it available!!
They will fit fine...
Cliff, Ian set me up with my Webers on a crate 302 with a turkey pan and anti-reversionary plate and all. The plate hit the glass so I'm running mine without it. The photo below shows the stacks under the glass with Inglese's filter screen slip-on rings. BTW, Ian, I got a nasty backfire on #5 yesterday and it blew the filter and 1 ring right off. I'm having it rough with the 2800 RPM transition.
Victor, do you have jetting information on your Webers?
Cliff, Ian set me up with my Webers on a crate 302 with a turkey pan and anti-reversionary plate and all. The plate hit the glass so I'm running mine without it. The photo below shows the stacks under the glass with Inglese's filter screen slip-on rings. BTW, Ian, I got a nasty backfire on #5 yesterday and it blew the filter and 1 ring right off. I'm having it rough with the 2800 RPM transition.
Victor, do you have jetting information on your Webers?
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Jcoop Weber transition
Hi J, what size idle jets are you running? If the engine runs fine above 3,000 and at full throttle you probably just need the next size larger idle jet.
Hi J, what size idle jets are you running? If the engine runs fine above 3,000 and at full throttle you probably just need the next size larger idle jet.
561234 said:
Hi David,
The idle jets were 70s. In reading the book, I saw that the baseline jets are supposed to be 55s. Also, they said that if I didn't get at least a turn out on the mixture screws to get best idle, they're too rich. I had taken a drive out to the Hamptons and the rear end was black and the plugs were sooty. Too rich, I thought, and that backfire (fouling new plug and over-rich) kinda confirms that so I changed them to 60s yesterday. I got just under a full turn out on the mixture screws. Idle is smooth, I now get a little lean sneezing just off idle, but that burping, coughing and bucking at 2800-3000 is still there. I retimed the ignition to show 34 deg. total with the vac. connected (at 3500 RPM). Maybe the main jets need fiddling? Maybe richen idle mixture screws a hair more on the idle jets, then go one rich on the mains. I may try that next. Then someone suggested go back to 70s but lean one on the mains. Trying hard to think methodically on this.
BTW, as an aside, I noticed some grease getting spat out in the engine bay. Last time I had that, the bolts holding the CV joint on the passenger side were a bit loose, so I had used plumber's glue on them and re-torqued. So I looked the driver's side now were all pretty loose; grease oozing off the caps. I think the added torque and HP (and a happy foot) with the webers are doing a number on the driveline. I better ease up before my Getrag blows up. I guess when they say the Audi box is good for up to 400 HP, they mean it. Must be closing up on that number.
Tim Kay
Lifetime Supporter
Gotta love those Webers
You may be doing this already but one small suggestion, when jumping from one idle jet to the next, don't go more the 5 units at at time ie. 55 to 60, 60 to 65. In fact my best tune was a 62.
If I am following the thread correctly, it sounds like your tuning delima is in the mid-range or "transition" area in which case the idle jet is less significant. It seems like a similar problem I experienced and my air corrector jet made a difference in the transition along with the above mentioned timing information (found my distributer was timed wrong - made a big differenct). 2cents
Ultimately, the stars must be aligned
You may be doing this already but one small suggestion, when jumping from one idle jet to the next, don't go more the 5 units at at time ie. 55 to 60, 60 to 65. In fact my best tune was a 62.
If I am following the thread correctly, it sounds like your tuning delima is in the mid-range or "transition" area in which case the idle jet is less significant. It seems like a similar problem I experienced and my air corrector jet made a difference in the transition along with the above mentioned timing information (found my distributer was timed wrong - made a big differenct). 2cents
Ultimately, the stars must be aligned
I re-timed the dizzy as jac mac suggested, 34 max at 3500 WITHOUT vacuum. Idle is 14 deg. but she seems to start up fine. Test drove WITHOUT vacuum and...Pops and Misfiring went away!!! Oh, and I also let out on the mixture screw to 1 full turn on all cyl. A little hesitation and stumble when I gun it from 1500 RPM but on a steady rising throttle, the acceleration is great up to 6000. I guess 60 is OK. Next one up is 70 in the kit they provided with the conversion. I'll order a set of 62s and see.
What number air corrector jet are you using, aladinsane? Main jets?
Thanks. Stars aligned at 11:48 this morning.
What number air corrector jet are you using, aladinsane? Main jets?
Thanks. Stars aligned at 11:48 this morning.
Tim Kay
Lifetime Supporter
JCOOP,
I went back over the thread, am I correct in seeing that you have IDA's? If so my settings won't help cause I was running IDF's therefore my earlier post will be moot.
In general, idle jets come in 5 step incriments. I bought a jet reamer tool and reamed my own jet size.
I went back over the thread, am I correct in seeing that you have IDA's? If so my settings won't help cause I was running IDF's therefore my earlier post will be moot.
In general, idle jets come in 5 step incriments. I bought a jet reamer tool and reamed my own jet size.
With IDFs, the idle jets are good up to about 2500- 3000 and then transition to mains until about 4000 then to air corrections I am told. At any rate, here is a nice doc on jetting webers - the theory is what is important here...I found it to be spot on when installing a dual weber IDF setup on a performance VW engine. You might find it helpful...
http://www.aircooled.net/gnrlsite/resource/articles/jetting.htm
Mike
By the way, I have a reaming kit and gauge kit and some loose jets I can send you if you return them when done.
http://www.aircooled.net/gnrlsite/resource/articles/jetting.htm
Mike
By the way, I have a reaming kit and gauge kit and some loose jets I can send you if you return them when done.
Mike, thanks so much for the offer and also the excellent link. I'll read up on that.
Right now, after I reset the timing and disconnected the vacuum from the dizzy, the Webers are singing! Man, it's sweet. I took a ride down to Bill Andrews HRE Motors in Freeport and not a single stumble. That racket the intake makes on acceleration is so sweet. Maybe I got it right by a long shot with the #60 idle jets and leaving everything else alone.
Or, perhaps, I'm just overjoyed that it's running smooth and the power is seamless, but could use some more fiddling. I should sit tight and check the plugs in a few more miles before I touch anything.
Cheers!
Ray
Right now, after I reset the timing and disconnected the vacuum from the dizzy, the Webers are singing! Man, it's sweet. I took a ride down to Bill Andrews HRE Motors in Freeport and not a single stumble. That racket the intake makes on acceleration is so sweet. Maybe I got it right by a long shot with the #60 idle jets and leaving everything else alone.
Or, perhaps, I'm just overjoyed that it's running smooth and the power is seamless, but could use some more fiddling. I should sit tight and check the plugs in a few more miles before I touch anything.
Cheers!
Ray
webers
The timing is very critical and it sounds like you are close on that. My carbs are IDF and the idle circuit is different on the IDA, you can keep the 60 idle jet and make a change on the air corrector that will cause small changes in the mixture, going from a f8-f7 will make idle circuit richer, going up will make it leaner. I have an Halmeter 30(gas analyzer) that I am going to install on my 347 and when I finish that I will post the results.
The timing is very critical and it sounds like you are close on that. My carbs are IDF and the idle circuit is different on the IDA, you can keep the 60 idle jet and make a change on the air corrector that will cause small changes in the mixture, going from a f8-f7 will make idle circuit richer, going up will make it leaner. I have an Halmeter 30(gas analyzer) that I am going to install on my 347 and when I finish that I will post the results.
