[Boidster]

What are the performance differences (if any) between the Holley "Street Performer Traditional" and "Street Avenger" lines? Application is a '67 289 with stock heads, Edelbrock Performer intake, Tri-Y headers, Pertronix ignition.

The work on my car is being done in CA while I'm in NE, so there is a lot of back-and-forth with the shop. In one of the latest pictures, the carb on the engine is almost certainly a 600CFM "Street Performance Traditional". I was originally thinking a 570CFM Street Avenger, but the shop owner does have some latitude from me to adjust specifications, seeing as he's rebuilt dozens of Mustangs and I have rebuilt zero of them.

Given that the car is staying classic (-ish; I mean it does now have headers and dual pipes after all - nevermind the shiny carb) and I'm just looking for some more scoot to surprise the occasional Civic (otherwise the car will be a rarely-driven street/highway car), am I going to sacrifice much with the "traditional" Holley vs. the Avenger? I notice the Avenger is more tweakable, which isn't necessarily a concern right now. I'm hoping that it's this tweakability that makes the Avenger such popular recommendation 'round here, and not that the traditional carb blows.

Latitude or not, I will insist on an Avenger if there is compelling reason to do so. Thanks for any input.

[cindys_sn95]

you will not FEEL any difference. very similar.

[Dave]

With the stock cam you could get by with even a smaller carb. I ran a Holley spread bore, think it was a 465 CFM and had great results with it.
Dave

[Boidster]

Yeah, the 570 was about the biggest I'd seen recommended in these and other forums, given my setup. As long as the 600 will be driveable, I suppose I'll have some headroom if/when I upgrade the cams. Of course at that point I'll probably want a more tweakable carb anyway and will move to an Avenger or something similar.