Power is off changes not helping.

Discussion in 'PSI Superchargers Tech Questions' started by Motorworx127, Sep 2, 2019.

  1. Motorworx127

    Motorworx127 Member

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    I am going to start with 20% over with a pill based on the 700cfm per rev and go easy she ought to be making lot more power no use in being stupid. if its fat so be it but at least with what ive learned here I should be able to get her dialed in gradually. It makes sense tho because as I tried his calculator I was going down from the 600 per rev not up which also confused the shit outa me. LOL:
     
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  2. Motorworx127

    Motorworx127 Member

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    This was definetly a learning experience as being new to this I wasn't able to determine my blower was weak. Hell it ran pretty good and I jumped from a 10 second ride into this so it was already a big difference. The set up ran just good enough to make everything confusing.
     
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  3. Motorworx127

    Motorworx127 Member

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  4. Mike Canter

    Mike Canter Top Dragster
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    I wouldn’t worry about percent of overdrive. What Boost was he expecting. To put you in the safe ball park you should be flowing .37 gpm per pound of boost. So at 20 lbs of boost you should flow 7.4 gpm, At. 25 lbs you should have 9.25 gpm and at 30 lbs you should have 11.1 gpm. When you get close to that you can adjust based on plug readings.
     
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  5. Bjs344

    Bjs344 Member

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    Mike, I’ve never understood that method. I took my heads cam and blower off of a 584 and put it on a 482. Boost went up a bunch. Fuel requirements changed very little.

    If you were talking about same cubic inch and same head, then I get it, but this is a larger Chevy engine. I’ve seen chevys require more fuel than a hemi for a given cubic inch and power level. Add in the extra cubes and it seems like a hemi rule of thumb could be very lean.

    I havent measured boost on mine in a while but will next weekend and will check to see where I’m at compared to your rule of thumb.
     
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  6. Motorworx127

    Motorworx127 Member

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    when I spoke with Spud he was thinking somewhere between 25-30 lbs at 30 over on my old blower I was making 15-18 at 30 over. Big difference in fuel requirements. It ran but was not the hammer I was expecting. But in a way might have been a blessing now I have some seat time, the chassis is proven and straight at mediocre power level, so now I can concentrate more on my tuning rather than an entire new build, new driver , new motor, new electronics. Big learning curve for my experience level.
     
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  7. Mike Canter

    Mike Canter Top Dragster
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    So if Spud was thinking you were going to make 25-30 lbs and you were only making 15-18 lbs you had two things agains you. That low boost made the tuneup super rich which was bad and you had low boost. Wow Spud’s original tuneup was probably right on for 25 lbs
     
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  8. Motorworx127

    Motorworx127 Member

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    I agree he told me to swap everything over to the BAU and new blower put in the 125 with no sizer and let her eat.. Not that the sizer is a bad thing just more complicated set up for a rookie like me. Ill say this although I was rich the truck ran and ran well, I have seen numerous other blown alky cars who hadn't invested the money to get set up and flowed prior to making a pass for first time, I came off trailer at 8.13 and when I was comfortable enough to stay in it put it in 7s on the startup tune. Ive seen these other guys blow up 2 engines and others that cant even make the 330 ft mark without popping and blubbering. The money I spent with Spud was probably the best money I spent on my build. I would recommend his services to anyone who is doing a blown alky setup novice or not. He has spent time on phone with me always answers my text questions Service is the key and his is as good as it gets in my opinion.. It clearly wasn't his fault my blower sucked.
     
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  9. Motorworx127

    Motorworx127 Member

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    You guys are great too! I really appreciate all the help.
     
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  10. Mike Canter

    Mike Canter Top Dragster
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    Let us know how it goes.
     
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  11. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    I don't want to step on anyone's advise given here, but I think spending the money to have someone flow your whole system.

    There's a lot more to a fuel system then what a lot of people even realize.

    Its definitely more money up front to flow a whole system, but it's hard to put a number on money you don't spend by either tearing parts up or wasting a bunch of trips to the track trying to dial in a system that isn't in the ball park.

    Here's a good video of what all goes into setting a fuel system up.

     
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  12. J.M.J pegasus

    J.M.J pegasus New Member

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    We had a similar setup in the past with slightly smaller bore,548,with 1471hh a littlefield 4"setback at 41%od...990 pump with loop,close to same hat nozzles, low 50s ports.it needed 10.3 gallons going in the motor for 30#s boost for 3/4 burn on the plugs..28* timing was the sweet spot for our combustion chamber according to the plugs..hope it helps..will is spot on with getting the fuel system setup and flowed,especially by randy anderson of APS..hes so helpful and help so much with my fuel system needs..after years of headaches ,mis-understanding,sleepless nights,empty wallets,eating ramen,cause of blown up junk..its worth the call imo..
     
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    Last edited: Sep 18, 2019
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  13. Motorworx127

    Motorworx127 Member

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    Hi everybody went an ran new setup today. The Superman made 32 lbs on my engine at 25% over. Plugs colored about 30% of ring on 1/8 mile hit and about 3/4 burn on 1/4 pass. Made huge gains now 7.17 at 188. probably still on fat side but safe. this was on .125 main . Im going to change nozzles in 2&1 to lean them up a touch but was checking 4 plugs today every pass to make sure we didn't miss a lean one. Had few issues getting the power to hook but pulled 14 degrees on hit with grid and ramped it back in over 1.03 seconds and it finally hooked and ran the best pass ever. I think 6s are just around the corner. Track conditions were marginal at best 60. ft was 1.15
     
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  14. Motorworx127

    Motorworx127 Member

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    Hey Will I did have Spud flow my system before we ever started but my blower never performed as expected. I am amazed it ran 7s on 18-20lbs on same fuel I just ran at 32 lbs. Spud was RIGHT ON THE MONEY.
     
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  15. Motorworx127

    Motorworx127 Member

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    ThanK You ALL for your time and Help
     
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