E-street vs Promaxx vs 440 Source
Frankly, his numbers seem a bit low.
I know the “original” cnc ported version of those heads were done by Modern, but they aren’t anymore.
The numbers from Modern were a bit over 320.
I had one of the Modern ported heads here several years ago. I tested two cylinders and they were basically 315.
The chambers were cnc’d as well, and Jeff’s valve job produced excellent low/mid lift numbers.
They were also ported “a lot”...... to the tune of the finished volume being 252cc(12 bigger than a TF240).
I basically get 280 out of a Stealth head with a valve job and the bowls blended(15-20 better than ootb).
I’ll be interested in the numbers Eric gets from an unported rpm head(that he mentioned in the video).
I do think this is likely a situation where comparing numbers from different benches could show a pretty big swing in the results.
Here’s a screen shot of the numbers from the video-
Frankly, his numbers seem a bit low.
I know the “original” cnc ported version of those heads were done by Modern, but they aren’t anymore.
The numbers from Modern were a bit over 320.
I had one of the Modern ported heads here several years ago. I tested two cylinders and they were basically 315.
The chambers were cnc’d as well, and Jeff’s valve job produced excellent low/mid lift numbers.
They were also ported “a lot”...... to the tune of the finished volume being 252cc(12 bigger than a TF240).
I basically get 280 out of a Stealth head with a valve job and the bowls blended(15-20 better than ootb).
I’ll be interested in the numbers Eric gets from an unported rpm head(that he mentioned in the video).
I do think this is likely a situation where comparing numbers from different benches could show a pretty big swing in the results.
Here’s a screen shot of the numbers from the video-
