Webers on a 289 from Shelby Engine
 

I am wondering if anyone here has a Shelby Engine 331 289 with Webers on it. I am considering that for my build. Thanks for any insights.

The coupe I was running at SAAC in Fontana had a 331 with Webers. One of the best engines I have ever driven. Loved it.

My 331 in my GT40 had 48IDA Webers. Ran like a raped ape

Thanks guys, now let me ask a further question. Is it possible for Shelby Engines to set up a Weber system on the 331 that is reliable, dependable, and doesn't need a Weber tuner in residence to enjoy driving in other than racing conditions?

Miky, not sure where you are located, but Jim Inglese (separate from Inglese Induction Systems) is a great resource for Webers in Cobras. Home

Reach out to him, he can answer all your Weber questions.

My Webers are on a 427w so it's similar but different from your setup.

Thanks dallas, I have talked to him, and am just trying to figure out who to get to build and set the Webers up. I know he comes highly recommended, so leaning that way when it is time. But, has anyone used Shelby Engine to do this?

Mine is a 289 0.10 over..........

48IDA via Inglese, did not want to rebuild Italian carbs

Thanks, I also definitely want modern Webers, not the original old style ones.

I run a 289 +.030 (292 and change) with an Original set of Italian 48 IDA’s circa 1964-65 (not IDA-1’s or IDA-4’s)carrying serial numbers; 983, 985, 1031 & 1035. A true early set. Mine are not drilled for the 3rd progression holes and they do have the screw down type accelerator pump jet nozzles, not the modern push-in type. No issues. I drive this car regularly (it is a GT350 not a Cobra) This motor is still in the car. I did consult with Jim Inglese 4-5 years ago for a base line for jetting but I have since modified it accordingly. I did this past year build a new engine; an 8.2 deck 4 bolt main block, steel 3.25 stroke big bore (I won’t call it a 331 though) which was designed for these Webers. I have yet to install and run it. The 289 on the other hand is still fairly running strong and trouble free (tuning wise). So we’ll see possibly later this spring for an engine swap.

Earl J

http://www.clubcobra.com/photopost/d...s/DSCN7353.JPG

Nice looking setup Earl.
Cheers,
Glen

Earl
They look awesome...........

I went with a known set versus the option of rebuilding a set from the 60's. If all was the same I would go Italian early, but all is not the same so I chose the high road..........

:)

Thanks guys, good info and insights here.

We do love our Webers!

http://www.clubcobra.com/photopost/d...S_427_005a.jpg

The only differences between new/modern 48 IDA’s and early that I can see are:
Early EW carbs up to “48 IDA-4” but not including do not have the triangle “V” bosses (for linkage?) on the outside of the bodies. The earlier carbs will also have serial numbers instead of date codes. I will not include the pre-48 IDA carbs known as the IDM which were also 48’s.

Internally, the EW IDA, IDA-1 and IDA-4 have the screw down jet pump nozzles with the check ball in the hold down screws themselves. I may be wrong on the IDA-4 which started production in the late 60’s early 70’s. There was a transition period where minor details changed, most notably the exterior vertical mounting bosses for linkage (I’m guessing) V8 applications don’t use them. All these 48 IDA’s came with two progression holes.

Modern IDA’s the ones from vendors like: EMPI, Redline and others or either cast “made in (blank)”, the ones from Spain, and back to Italy or South America and China (more currently) are pretty much the same design. The details I’ve seen are the push on jet nozzles that take the rubber “o” rings and more currently the 3 progression holes. Machine screws are used (on modern) instead of studs and nuts found on early body and air horn attachment methods. That’s about it.

Construction quality on modern units is an unknown to me. So just be careful and be VERY selective if you’re buying used pieces. (Other people’s frustrations) Also check the number of progression holes between ALL the carbs.

The bad thing about buying used is; I wouldn’t trust the jetting in them as some previous owners modified them (soldered and or drilled out) so what they read may not necessarily be what they are. Just so you know what “stock” 48 IDA’s came jetted brand new out of the box (at least early originals):

37mm venturi
4.5 Aux Venturi
135 Main Jet
F7 E-tube
120 air corrector
120 Idle jet holder
70F10 Idle Jet
50 Pump Jet Nozzle
50 Bypass Jet
25.5 Float
200 Needle Valve

I would talk with Jim Inglese as noted earlier for a base line jetting based on your car specs. Jim will ask. If he does set you up MAKE SURE you ask him what size he drilled or modified a particular jet to. As he will grind off the size leaving you clueless.

Lastly read Tennessee Tim’s Weber Tuning Tutorial posting here on the CC forum. It is one of the most informative writing pieces available anywhere. It’s currently free. It’s better than most books out there.

Have fun.
~Earl J

Thank you! Very complete and descriptive for a novice like me. One additional complication, that I have talked to Jim about, is that I live near 7000' and much of my driving will be from there up to 10,000' or so, as we have some great mountain roads around here for rallies, cruises, etc. He indicates the jetting would be critical for this situation, and a special item to focus on.

Here is a picture of what is being suggested.

It's nice looking. Looks like Joe at Denbeste Motorsports has built you up an all aluminum 331 with Webers. Careful, the intake valve size on those heads are 2.08 and with a port volume of 205cc, unless you specified differently. If that is your motor, you’ll have to adjust tune it to your altitude.

Best,
Earl J

You're right all around. I will probably need to understand these Webers as well as I understand my '68 Holley 9510 carbs.

260 c.i. webers
 

Insert Photos and Images

My 48 IDA webers from Jim Inglese. Jim had to custom make the 34 mm chokes for the 260 c.i. size. Jim supplied the complete Intake set up.

Valley Head Service did the porting and installed the larger valves.

Bullet Racing Cams made the roller camshaft- intake lift .3283 duration @ .50 223, Exhaust lift .3283, duration 227 lobe seperation is 110, Jim said that the lobe seperation will work fine. I hope that I won't have blow back into the carbs. Maybe 112-114 seperation would work better.

Crower roller rockers and Racetec pistons