Supercharger Efficiency and Weak Numbers

[dsmx17]

Dyno sheets don't have psi or a/f charts?

Not if they printed a basic run, dynojets CAN print rpm/speed/whp/tq/boost/ambient temps etc... doesnt mean they logged it all

 

[ScottsVaporGT]

I would think of finding a different tuner. If he didn't give you any more info than "blower is to small" then I don't know that I would trust his word/work. To me that is kind of a bullshit answer. I would think that he might offer some suggestions to you on what you might be able to do. Ask him to send you a copy of your sheet, or go pick one up if your close. Call him up and ask some ?'s. Good luck and I hope it works out for you.

 

[Jeffs FRC]

Not if they printed a basic run, dynojets CAN print rpm/speed/whp/tq/boost/ambient temps etc... doesnt mean they logged it all

Everytime i've had a car dyno tuned I had the a/f included on the sheet. Never had a boosted car, but friends with blowers all had boost levels along with a/f...

I would think of finding a different tuner. If he didn't give you any more info than "blower is to small" then I don't know that I would trust his word/work. To me that is kind of a bullshit answer. I would think that he might offer some suggestions to you on what you might be able to do. Ask him to send you a copy of your sheet, or go pick one up if your close. Call him up and ask some ?'s. Good luck and I hope it works out for you.

Kinda the feeling Im getting too. Doesn't seem like much communication is going on with the tuner and thats never a good thing.

 

[redstangs9308gt]

wow that really sucks. super low numbers. maybe its the low compression of the aluminator comning in to bit your ass.....

 

[MexGT]

wow that really sucks. super low numbers. maybe its the low compression of the aluminator comning in to bit your ass.....

huh?

 

[NastyStang113]

LOL...

 

[SirKnightTG]

Found the problem! You have something from MMR on your car. Take it off and it will run like a champ.

OP, where did you get the tune and who built the engine?

 

[lostsoul]

8.7:1 is too low ... unless your going to run an f3 procharger on 93 octane.

 

[LAK3RS]

This is a fine example of why I'm scared of the Aluminator. The compression is to low, as mentioned above. Of course, there could be other issues invloved.....

 

[lostsoul]

I was told by many to stay around 9.1 ish ... now I have a killer block with 15# procharger ready to rip Don and Wheelers ass!!!!



































.... just sitting on the garage floor for a year now.. .... yeeeeea

 

[redstangs9308gt]

Yall thought I was joking by my goofy post? I was almost serious. When I put in the aluminator with stock heads cams I was like WTF,,,,,is it just me or is this a little slugish. Like I said in the other forum about my car, I am either WFO, or Grandpaw driving. Seems like the car doesn't have the touchyness of the throttle anymore. Its hard to discribe, and NO I am not being tooo sensitive or picky. I could tell a huge difference in Same size pulley, Only thing changed was the factory bottom end to the aluminator with lower compression. I don't know, little more time and I guess I will know more about my situation. Damn this snow!
Nick

 

[LAK3RS]

Is there really that big of a difference between 8.7:1 and 9.1:1 compression ratio? From what's described above, there is. It's as if it's pointless to combine a 2.3L supercharger with the Aluminator....

 

[redstangs9308gt]

I went from the factory 9.7 or 9.5 to 8.7......I think that is what the factor 4.6 is right?

 

[classix_stang289]

before you blame things on the aluminator, re-check the tuning.

 

[classix_stang289]

also like mentioned already, are you running stock heads/cams? do you have longtubes? gears? drop the cats and see if there is any other supporting mods for the supercharger that will help out big time.

 

[timfoster405]

Guys... thanks for the catching that. I typed the wrong number... I realize the 14.7 is the a/f ratio that you see while at part throttle when you are cruising and would trash a motor (atleast stock internals) if you had this a/f during WOT. I fixed my previous post.

 

[Hatchman]

I went from the factory 9.7 or 9.5 to 8.7......I think that is what the factor 4.6 is right?

Stock is 9.8, so 8.7 is a big drop. My car with 8psi put down 440rwhp SAE with safe timing, which is not far off of your 430rwhp with less compression.

Since we don't know about the boost and belt slip for the smaller pulley, can't really say what is going on. Then again, a dyno is just a tuning tool, best thing to do is take it to the track, or do some runs with a G-tech or similar (since most of the tracks are closed now) and see how she's running. My G-tech is usually less than .1 sec and a couple mph off my timeslip, close enough for government work, LOL! And if you don't want to do the full 1/4 or 1/8 mile runs on the street, you can always do a 0-60mph on a nice straight 'back country' road and see how's she's doing. With good tires and suspension, you should be able to knock down a 4.2-4.3 sec 0-60, at least that's what I get. I get a guilty conscious doing a run over 80mph, but a quick zero to sixty with no cars in sight for miles is OK in my book.

 

[timfoster405]

For the GT500, the compression ratio is only 8.4...see specs below for the 2009 model:

Specifications
2009 Ford Shelby GT500 Base Coupe Performance & Efficiency Standard Features -
One supercharger compressor
5,411 cc 5.4 liters V 8 front engine with 90.2 mm bore, 105.8 mm stroke, 8.4 compression ratio, double overhead cam and four valves per cylinder

​

 

[ZmanM3]

I went from the factory 9.7 or 9.5 to 8.7......I think that is what the factor 4.6 is right?

Factory 9.8:1

 

[BlownAway05]

Terminator's run 8.5 compression, they seem to run damn strong with a 2.3 whipple. Hard to believe that a 3V with a little more compression would offer so much less than a 4V