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Discussion Starter · #1 ·
could small jets cause a motor to not pullin hard in the upper RPM.....or would a jet change just be notice a litte on a timeslip
 

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I've had them where 1 or 2 numbers made all the difference in the world. So I'd say yes, small changes can definitely affect top end pull and rpm.
 

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Generally speaking, without using any sort of standard and accurate measuring device, you are unlikely to "feel" seat of the pants a change of one jet size in the secondaries at wide open throttle/

It is possible however that if you are on the border of a lean condition and detonating, for instance, a one jet change could make a difference. You'd be more likely to notice a jet change in the primaries, driving at part throttle.

In the next issue (later this week) you will see an article on carb tuning using a wide band 02 sensor (see Innovate ads on the right). With this device you can see the impact one jet change has one Air/Fuel ratio and acceleration.
 

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Is it laying down in high gear at the track? Probably fuel delivery problem under load, usual culprit is a stock, or near-stock fuel system.

Doubtful that one jet size would be noticable in anything but a dangerously lean condition; Holley recommends stepping up in 2 or 4-size increments until the engine slows down. There is a lot of good info in their catalog, and several good books.

BOB
 

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Discussion Starter · #7 ·
after it gets to 6k......it jus stops pulling like it does under 6 and i know that cam makes power past 6k.........i was just thinking there wasnt enough fuel gettin threw because of the jets being to small....but i had a stock pump on it b4 and i jus put a holley blue on soo this weekend ill see what happens

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'69 fastback --302, 289 heads ported w/ big valves ,10:1, torker intake, 600DP, 294/.569 solid, C4 w/brake , 4000 stall, 4.11's


<font size=-1>[ This Message was edited by: fender2k5 on 6/22/06 3:04am ]</font>
 
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