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Black Baja 06-10-2015 07:17 AM


Originally Posted by TAStevens (Post 4315571)
Tom doesn't have AFR on his old Dyno...Plugs looks like is close to melting! QF sent these with a PV in the front...none in the back...laying in bed last night..was thinking adding a PV to the back? Fuel Pressure is rock-steady 7.8 to 8 psi Float levels are perfect (love those big sight plugs) Going to call QF today...wondering if they have "different" metering blocks available?? I personally havnt touched a card in 25 years...But Tom and John does this ALL the time...some pretty sharp minds in that room. Engines are gonna be stout! And YES ...1050 Dom

Does the dyno have EGT's for each cylinder? If so what are they? Did anything respond when you jetted up at all? (Plugs, egt's) if nothing responded at all to the larger jets I would bump the float levels up say to 3/4's glass maybe a touch more. I know they say with the new bowls it's 1/4 glass but I've found that to low and above half is where they need to be. That carb should be no-where near lean at that horsepower/rpm level. I'm not trying to discount your friends tunning expertise in any way just some ideas from what I've seen. If you bump the floats and no response send the things back cause something is way off...

fbc25el 06-10-2015 07:50 AM


Originally Posted by TAStevens (Post 4315571)
Tom doesn't have AFR on his old Dyno...Plugs looks like is close to melting! QF sent these with a PV in the front...none in the back...laying in bed last night..was thinking adding a PV to the back? Fuel Pressure is rock-steady 7.8 to 8 psi Float levels are perfect (love those big sight plugs) Going to call QF today...wondering if they have "different" metering blocks available?? I personally havnt touched a card in 25 years...But Tom and John does this ALL the time...some pretty sharp minds in that room. Engines are gonna be stout! And YES ...1050 Dom

Can you post what the tune up is . There's a lot more than just a main jet change.

frickstyle 06-12-2015 10:51 AM

Tim,
What ended up happening with the dyno runs?

TAStevens 06-12-2015 11:00 AM

Well...when the "wizard" at QF assembled this card...it was to have a pait of 73 "jets" behind the Power Valve......After beating by head agaist the wall lonbg enough..I dissected that Carb and found he put BLANKS in it! (and one wasn't even tight(! Hard to pass fuel through those when the PV opens! I take the carb of the second engine, pull that one down...at least he put 68's in that on?? WTF! I also borrowed a Wide Band O2 sensor (that verified my BSFC #'s btw) Were up to 765 now...gonna bump timing and add fuel in a couple hours:cool-smiley-011: Its a "grunter" 563ft lbs torque at 2000rpm! Should get up on plane?!

Full Force 06-12-2015 11:00 AM

I used water dyno haha

TAStevens 06-12-2015 11:09 AM

Glad I didn't just bolt these in and run across the Lake...would of melted the engine with the f'd up carb for sure!

Full Force 06-12-2015 11:11 AM


Originally Posted by TAStevens (Post 4316802)
Glad I didn't just bolt these in and run across the Lake...would of melted the engine with the f'd up carb for sure!

Crazy mine were right on...

SB 06-12-2015 11:12 AM

So, your PV Channel Restrictions 'jets' where solid ?

Damn.....

TAStevens 06-12-2015 11:22 AM


Originally Posted by Full Force (Post 4316804)
Crazy mine were right on...

The other wasn't "too" far off...but the AFR was 12.8...pushing 13 and BSFC came down to 440ish still a tick lean...first pull today will be with a "fatter" tune and if all looks good..finally bump timing..glad I had that backed down on that first carb! I a "newbie" to the Water but this isn't my first rodeo in the Dyno room:violent040: Built many 3,200hp engines....havnt touched a carb in 25 years though

TAStevens 06-12-2015 11:23 AM

YEPPER! How F'D up is that...PV BLOCKED!


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