Pettit Super Charger Owners
11-21-2008, 09:57 AM
#3626
Dongbag extrordinare
Join Date: Nov 2004
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Just for your edification, this is what the MAF/Load values are for my turbo car at 9 PSI:
This is just a casual rip through second and third on my street. Didn't even take it to redline.
As you can see, the MAF is pegged at its maximum value (369 g/sec) so, who knows what its actual flow is.
ABSLoad hits 2 in some spots (also pegged) - all at considerably fewer RPM than the S/C.
Fortunately, the fuel calculations continue to stretch until the end of the available injector flow or this would all end very badly.
So, take your understanding of power and how it relates to MAF flow with a grain of salt.
Data is below.
This is just a casual rip through second and third on my street. Didn't even take it to redline.
As you can see, the MAF is pegged at its maximum value (369 g/sec) so, who knows what its actual flow is.
ABSLoad hits 2 in some spots (also pegged) - all at considerably fewer RPM than the S/C.
Fortunately, the fuel calculations continue to stretch until the end of the available injector flow or this would all end very badly.
So, take your understanding of power and how it relates to MAF flow with a grain of salt.
Data is below.
11-21-2008, 10:40 AM
#3627
However, this will change the scaling of the load value and, to be perfectly honest, the car is running like a raped-ape right now and I don't feel compelled to play with it until the race season is over.
My reason for posting that was to point out that the MAF reading, while interesting, is not particularly useful for computing net power output.
Around here, prices have only dropped a few percent.
Why?
I don't spend too much time in 6th, other than on the highway.
11-21-2008, 04:24 PM
#3637
The Local Idiot
Join Date: May 2008
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As you can see, the MAF is pegged at its maximum value (369 g/sec) so, who knows what its actual flow is.
ABSLoad hits 2 in some spots (also pegged) - all at considerably fewer RPM than the S/C.
Fortunately, the fuel calculations continue to stretch until the end of the available injector flow or this would all end very badly.
ABSLoad hits 2 in some spots (also pegged) - all at considerably fewer RPM than the S/C.
Fortunately, the fuel calculations continue to stretch until the end of the available injector flow or this would all end very badly.
11-21-2008, 04:30 PM
#3638
Not to derail this thread, but are you saying that rather than have a MAF that is giving you a proper reading that you tuned your car by manually adding more fuel in situations where the MAF is pegged in order to hit your target AFR? Isn't that a giant PITA, or am I totally confused about something here?
I would much rather tune for what it is seeing (and I will).
However, because of the way the fuel tables are set up, I get the proper AFR without doing anything (because of the LOAD balance provided by the other sensors), so I don't have to worry about it at the moment.
When I have more time, I'll extend the MAF range because its the right thing to do.
11-21-2008, 04:59 PM
#3640
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Well, lets just say it offsets the driver. Its about the same weight as the 1.7s, havent scaled it yet but im sure its within 10 pounds, atleast my back says so. With a little more relocation I bet I can get a 2.6 in there, its only fatter.
11-21-2008, 05:41 PM
#3641
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Just changed/added a pair a AT secondary injectors to my car last night. I don't have a log yet but after taking the car for a short spin (12:15 AM) I noticed that my AF reading was @ 11.5 per my AEM gauge on a couple of 1, 2 and 3 gear runs. 
11-21-2008, 07:21 PM
#3645
Left handed scissors available for RHD??
It doesn't look that much higher than he normal pettit setup, looks like about an inch spacer is needed on the intake. People don't realise how low this motor actual sits. I showed my setup as SSX and someone thought it would need a scoop on the hood. Until I told them it all fits under the engine cover
Cheers,
Hymee.
It doesn't look that much higher than he normal pettit setup, looks like about an inch spacer is needed on the intake. People don't realise how low this motor actual sits. I showed my setup as SSX and someone thought it would need a scoop on the hood. Until I told them it all fits under the engine cover
Cheers,
Hymee.
11-21-2008, 07:41 PM
#3647
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That was the plan but theres no way it would fit. Im gona give it a week before I start mounting it, Try maybe a couple of different settups. The thing is it needs the output at that point to give you un restricted output. I see no reason that I cant locate the throttlebody as close to the intake as I can, and its big, I can stick my fist in it. The output is bigger also.
11-21-2008, 08:13 PM
#3648
poor, poor exhaust ports!?
I knew ole Moon had to try on the rene--i would like to see the eye ball scoop on the hood! I will bet that a cog drive will have to be fitted on that dang thing. It will sound like the ole cruising days in the 60's! will need a bigger fuel line--dont we have the 5/16th
MM because you will not peg the maf in 6th gear
Rote call snow they upgraded the nozzle holders to all metal -they are free for you
Juan you always beat me too it! Fuel pressure ok? at what duty cycle are we at with the flash?
stay tuned for some fuel system/pressure work--soon as i get my yukons on--they will be here next week.
Anyone tried BK syncroshift?
OD
I knew ole Moon had to try on the rene--i would like to see the eye ball scoop on the hood! I will bet that a cog drive will have to be fitted on that dang thing. It will sound like the ole cruising days in the 60's! will need a bigger fuel line--dont we have the 5/16th
MM because you will not peg the maf in 6th gear
Rote call snow they upgraded the nozzle holders to all metal -they are free for you
Juan you always beat me too it! Fuel pressure ok? at what duty cycle are we at with the flash?
stay tuned for some fuel system/pressure work--soon as i get my yukons on--they will be here next week.
Anyone tried BK syncroshift?
OD