Effectiveness of Webers on High Output Engines

[pezzonovante88]

Hi, I'm new to the forum (and to high-capacity American engines). I have some interest in a 482ci (stroked 427) with Webers and have a few questions.

-Say, for instance, a Keith Craft built aluminum motor with double quads putting out 640hp; would 48IDAs be an effective alternative on an engine like that? If so, what difference in output and in power delivery, sound etc. would the Webers make?

They just look so damn good and have that extra little bit of mystique.

Thanks!

[ERA Chas]

48 IDAs would not be adequate on an engine of that size and intended power. 58 IDAs are required and are either very scarce or a similar system can be delivered by Berg.
Only back to back testing on either dyno or track will tell you if they're an improvement.

[Igofastr]

Chas is probably right.

At 482 ci, you'd likelyly well be beyond what a standard 48 IDA can flow, but it would depend on the build. I'm at 393 ci, and did 601 bhp on the dyno. As it stands, it looks like I'm running out of air at about 6.5K rpm. I put slightly larger venturis in, but to get much larger, you'd need some machine work. That can get fairly expensive.

For your motor, the next step would be 58s, if you can find them.

Gene Berg would be a good place to look, though. The VW drag racers use some pretty big webers.

[pezzonovante88]

Indeed, Berg, I forgot about those.

[D-CEL]

pezzonovante88,

I think the short answer is "yes, you could make near 650hp with a 482 ci FE with a set of 48s (As Chas said, bigger would be better)
But....It would be a poor street motor: peaky, angry, temperamental and a generally grumpy bastard!

In the end I think you would be wishing you had spent the large pile of dollars it took to build such a beast, differently.
I wont deny that Webers look great and that keeps the "Mystique" alive. But as I have said before, they are much better on a garage shelf than in a running motor.

Individual Runner EFI is a better option if you want "The Look" and you want it to run like it should.

Jason

[zrayr]

Originally Posted by D-CEL

"………………...
I wont deny that Webers look great and that keeps the "Mystique" alive. But as I have said before, they are much better on a garage shelf than in a running motor.

Individual Runner EFI is a better option if you want "The Look" and you want it to run like it should…….."

it's a shame you think a Weber equipped engine can't "…run like it should…" or that they belong "…on the shelf…."

apparently you have the mindset that Webers are too complex or too ancient to be considered for use on a car that is in regular service. They are completely street-able once set up right. End of story.

Nothing wrong with EFI, but it is not a substitute for a vintage look & vintage performance. I had Webers on GT350's and also on my current 289 K code Mustang. Completely street-able, regardless of displacement.

Z.

[Stentor]

The 58mm IDAs do pretty well on my 511 ci FE.

[Gaz64]

Originally Posted by zrayr

it's a shame you think a Weber equipped engine can't "…run like it should…" or that they belong "…on the shelf…."

apparently you have the mindset that Webers are too complex or too ancient to be considered for use on a car that is in regular service. They are completely street-able once set up right. End of story.

Nothing wrong with EFI, but it is not a substitute for a vintage look & vintage performance. I had Webers on GT350's and also on my current 289 K code Mustang. Completely street-able, regardless of displacement.

Z.

Completely agree.

I've had many IR weber equipped cars, all have been completely streetable, some of which could have been cammed up more.