Author Topic: New engine size dial in  (Read 3013 times)

Offline oktorque

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New engine size dial in
« on: December 09, 2014, 06:42:35 PM »
I have a 17059547 for a 231 turbo v6.  I have had great success putting QJ's on beefed up ford I6's. 

The engine this one is going on has zero emissions and oversize valves with a porting job.  It is also in a full size truck. 

Does anyone have advice as to how to set it up for the initial run?  I want to open the idle tubes and down restriction a few thousandths, and believe it will need up around 72 jets and Cliffs 44 rods.  But what about the air bleeds?  Should I leave them original? 

Thank You.

Offline oktorque

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Re: New engine size dial in
« Reply #1 on: December 10, 2014, 02:52:52 PM »
I'm curious about the main air bleeds.  It was a turbo carb.  I'm thinking that means large quantities of air pumped in, so the bleeds were kept small, rich?  Should they be opened slightly? 

Does anyone know?

Offline oktorque

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Re: New engine size dial in
« Reply #2 on: December 13, 2014, 03:12:32 PM »
The main in the air horn is .045

The idle down restriction is .058

The main bleed in the main body is .051

Upper idle bleed is .051

Does anyone know a good starting point for a 250 hp 300 in a full size p/u?  I thought I'd read some threads and set it for a 305 or 307.  Or, simply use Cliff's First recipe, on the lower end of the scale?

I'm surprised the idle down restriction is so large, when all the other bleeds and restrictions are small compared to the first recipe.

Offline oktorque

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Re: New engine size dial in
« Reply #3 on: December 14, 2014, 07:09:30 PM »
Well, I have to say that I am surprised.  This is supposed to be the premier forum for QJ's, yet not a single response.  I assume that is because I'm out there in the grey area, where few have gone before.  That is understandable.

After re reading Cliff's book, I am understanding the relationship between bleeds and fuel flow.  I was hoping that a more experience QJ guy would come on and say, 'yes, I'd start with such and such size main and idle bleeds.'  But no.  So, I found that with a 231 v6 turbo QJ, the bleeds were around .050 with 67 main jets.  For a trans am with a 301, the bleeds were about .065 with .072 main jets.  I believe I will begin there.  The 301 spins faster, whereas the 300 I6 tops at 4500 rpm, but the engine is working harder, pushing more weight with a truck body, so, I'm thinking the larger mains may be needed. 

Note to help others:After reading Cliff's book several times I was still confused regarding the Upper idle air bleed and the main air bleed in the air horn.  Photos showing either one are on different pages and should be side by side.  The air bleeds seemed one and the same to me.  Then I noted, if the orifice is right beside the air  horn screw it is the main air bleed.  If, however, the orifice is not on the little nub or mound beside the screw hole, but closer to the vertical choke flap 'wall', then it is the upper idle air bleed. 

Offline 429bbf

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Re: New engine size dial in
« Reply #4 on: December 17, 2014, 09:21:30 AM »
i would built it to receipe 1 and start there . that should give you a very good start. it works fairly well for a starting point for a 302 ford. with a few minor adjustments. as to your coment on the main bleeds and idle bleeds i believe he wrote it to be very specific . the IDLE SYSTEM section talks about the  idle bleeds and the MAIN SYSTEM talks about the main bleeds .i think if he had mixed them all together people would be very confussed. fwiw

Offline oktorque

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Re: New engine size dial in
« Reply #5 on: December 18, 2014, 09:47:19 AM »
Thank you for the reply. 

I notice that my idle down restriction is remarkably large, .056, iirc.  Does Cliff sell plugs that can be drilled to recalibrate that restriction?  And, if so, are the old easily removed? removed like the idle stems, with a screw?

Offline Cliff Ruggles

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Re: New engine size dial in
« Reply #6 on: December 18, 2014, 09:59:44 AM »
We sell drive in and screw in restrictors, the casting will need to be tapped for the screw in variety....Cliff