09-19-2008, 10:01 PM #1
Blue velocity stacks vs stock airbox
I tested a set of throttle bodies equiped with aftermarket velocity stacks, they look like the ones Ross uses. These TB are NOT Ross's, they are stock with velocity stacks & the top of the TB blended to match the stacks. I got them from another member, thanks James. The motor in my 08GPR is stock except for indexed iridium plugs & an EFI controller. I removed the stock airbox & TBs and installed the modded TBs. I was suprised that I saw no peak RPM increase 7260 cold motor, this might have been down just a little. It did seem to have better low & mid range punch.
Next I will be adding some VF3s, now you guys can quit telling me I should ditch the EFI controller. I told you I was gona need it soon.
09-19-2008, 10:04 PM #2
09-19-2008, 10:13 PM #3
Yes, I tried adding a little fuel. I only got to ride for less than 15 min., I didn't even pull my truck off the ramp. It was dark before I could do much testing.
09-20-2008, 12:00 AM #4
(I removed the stock airbox & TBs and installed the modded TBs. I was suprised that I saw no peak RPM increase 7260 cold motor,)
The velocity stacks are only part of the equation.....I do much more than just add velocity stacks to the throttle bodies..
Another thing, at 7260, you are on the outer limits of the velocity stacks torque curve.
7290-7300 seems to be their limit.. Bend your impeller, get your rpms in the 7100-7150 area and you may see more speed...
Or send them to me and i will fully port them for you for max performance.
Aint nothing like owning the real thing.
09-20-2008, 08:08 AM #5
I was in no way trying to imply that these were comparable to your modified TBs I was just posting my results. I am planning to get a set done by you, I just got a good deal on these.
About the peak rpm I was thinking the same thing, way past peak torque. I do plan to mod the prop but maybe not till next year, it's getting cold here & dark early. I have a set VF3s on the way I think I'll install them and call it good untill next year. Good weather = more mods.
Thanks for your input.
09-20-2008, 03:48 PM #6
Hi Syclone,anytime you extend the length of the stacks you will gain low and mid which you prob found with this set and Ross does a few more tricks besides port match only but this you know You do need the VF3s and will like the combo together when you get it set up... Thanks for posting your results
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