|
|
|
|
| Author |
|
|
Registered
Join Date: Apr 2002
Location: NoCal
Posts: 2,416
|
2.4E jetting recommendations, and other general jetting questions
I posted this on the main board, but got little response, so I'll try here:
I have a 1972 911T with a freshly rebuilt 2.4E spec motor, using 2.2E pistons, as per Wayne's book. In order to defer the $2500 or so it will take to rebuild the MFI properly, I picked up a set of Zenith carbs cheap, and have since rebuilt and installed them. Good news: the car runs okay now, which it not do with the worn out MFI. Bad news: it doesn't run great, probably because I made no jetting changes before I put them on the car. Anyway, I'm running the following jetting: Venturies: 30mm (I bored them out when I had the carbs apart) Main Jets: 115 Idle Jets: 47.5 Air Correction: 195 Emulsion tubes: 30 (?) Anybody have a baseline for my particular engine? I've done some pretty extensive searches on this board and others, and I found lots of info on Webers, but little on the Zeniths. I'm assuming my carbs are still set up for a 2.2T. More to the point: Will Weber specs work as a baseline? Being a machinist for a dozen or so years, I'm not afraid of putting my jets on the lathe and reaming them to work with my particular motor. From what my research has uncovered, a 55 idle jet is .55mm, a 150 main is 1.50mm, and so forth. Am I close? Am I crazy? If I go a bit too far, I'm sure I can find used 2.2T Zenith jets and start from scratch. Thanks, Jim |
||
02-22-2005, 11:32 PM
|
|
|
Registered
Join Date: Dec 2001
Posts: 4,313
|
Don't know how close the Webers are to the Zeniths but here is what I'm using on my 2.4E w/40mm webers & sport muffler. I checked this set up with the LM1. Motor runs very well with no flat spots, but could use a little more fine tuning.
mains 125 air cor. 180 emul f26 idle 55 venturies 30.
__________________
Harold '79 930/DP935 (sold) '68 VW 3.3 Turbo Crewcab |
||
|
02-23-2005, 07:19 AM
|
|
|
Registered
Join Date: Aug 2004
Location: Houston, TX
Posts: 895
|
for reference...
had my webers set up on the dyno with the same motor as you (2.4E with 9.6:1). in addition, i run a crane xr3000 ignition. i'm using 60 idle and 130 main with 34mm venturies. the emulsion tubes and airs are stock. so i only had to bump up the idle and mains one size... prior to this, then engine was a stock 2.2E. the carbs were set up on the same dyno at 60 idle and 125 main, with 30mm venturies. all else the same. hopefully this helps some.
__________________
Matt 72 911T Targa - Sold Hang up the cell phone. Put down the Latte. Ignore the kids in the back seat. Use your blinker when you want to change lanes. AND DRIVE YOUR Fu@#!NG CAR!! |
||
|
02-23-2005, 10:01 AM
|
|
