SoCal Jet Boats

Tech Talk => Engine Mechanical / Electrical => Topic started by: 74RogersBubbledeck on June 04, 2012, 08:10:43 PM

Title: Carb jetting question
Post by: 74RogersBubbledeck on June 04, 2012, 08:10:43 PM

Bought a Quick Fuel Technologies 750 Blow Through for my Procharger a few years ago while running a BBC 454 Magnum at 5 psi of boost.

Now I'm running a 468 that is much stronger than the previous motor. Some highlights of the set up are as follows:
Strong bottom end
JE Flat Top Pistons 8.1 Compression
Comp Cam 11-568-4 Nitrous HP
Comp Pro Magnum Lifters (Stayed flat tappet)
Manley Push Rods
Iron square port heads with ports cleaned up
Teague 1.7 Roller Rockers
Edelbrock Victor Jr (Port matched)
M3 Procharger with 9psi of Boost
Fuel system designed for this application
Bassett Headers (So loud can't even talk at idle)

Ran for a short time at the end of the season to break in and check everything. The spark plugs are white. No pitting or signs of melting, simply white like new.

I want to see a golden brown don't I?

Currently have jet size 76 in primary and 86 in secondary.
I have 77's and 92's sitting in a bag and thinking about trying them. I feel like the secondary's are going to be more important, but want to hear from those with experience setting up HP motors.

I don't have any pics of the plugs right now, will post when I do

Title: Re: Carb jetting question
Post by: NoRestraint on June 04, 2012, 08:36:21 PM

what kind of plugs are they?

Title: Re: Carb jetting question
Post by: 74RogersBubbledeck on June 04, 2012, 08:57:40 PM

I should have thought about that before I posted. Procharger recommends a colder plug which is what I asked for at Teague when I bought them. I'll get it tomorrow when the sun is up  :o

Title: Re: Carb jetting question
Post by: raginaquaholic on June 11, 2012, 10:23:46 PM

My jets are set to carburetor specs. Went out on the water today & pulled the #1 & #8 plugs when I got home. The plugs were dry & very black? I don't think I could be running rich.   

Title: Re: Carb jetting question
Post by: raginaquaholic on June 26, 2012, 10:47:04 AM

Finally feel I got the correct jetting & power valve combination. Far more responsive than before. Hit a swirl at WFO gained altitude & landed 180 degrees. Without the NOS.

Title: Re: Carb jetting question
Post by: ka0tyk on June 26, 2012, 11:11:09 AM

Quote from: raginaquaholic on June 26, 2012, 10:47:04 AM

Finally feel I got the correct jetting & power valve combination. Far more responsive than before. Hit a swirl at WFO gained altitude & landed 180 degrees. Without the NOS.

lol i almost shit my pants when i spun out after goin thru a wake.  hopefully something ill never have to experience again.

Title: Re: Carb jetting question
Post by: raginaquaholic on June 26, 2012, 11:34:55 AM

Definitely one of those WTF just happened moments. :screwy: