Paxton drivability questions

[rfugio68]

Well I'm getting close to ordering a supercharger for the 5.0, and I was sold on beefcakes kit, however one of the most known tuners told me that "Paxton's are the worst kits for drivability". This concerns me because I drive ~2000 miles a month, and it has me considering a tvs with intake/tune because it's essentially the same price or even a kenne bell 2.8LC for a little more. So for you Paxton owners, how has your drivability changed since you boosted your 5.0?

 

[Justin81]

What exactly did your tuner say about the poor drivablity? Was he any more specific?

 

[rfugio68]

What exactly did your tuner say about the poor drivablity? Was he any more specific?

Not specific at all, just basically said that the drivability is no where near as good as the roush/whipple kits.

 

[lovebread]

Either you're in boost or you're not. The car drives as well as you's think a big turbo v8 would drive, it's all in the tune. Expect terrible gas mileage anywhere close to 650hp+. Around city I'm seeing about 13mpg, highway 20+.

I'm looking to swap to 3.31s for drivability.

 

[CSG]

My tuner says that his Paxton cars drive really well but that the TVS is more stock like for whatever that is worth...

 

[92fiveohfox]

Either you're in boost or you're not. The car drives as well as you's think a big turbo v8 would drive, it's all in the tune. Expect terrible gas mileage anywhere close to 650hp+. Around city I'm seeing about 13mpg, highway 20+.

I'm looking to swap to 3.31s for drivability.

What are you swapping for MPGs? "Drivability" is pretty vague.

 

[rfugio68]

Either you're in boost or you're not. The car drives as well as you's think a big turbo v8 would drive, it's all in the tune. Expect terrible gas mileage anywhere close to 650hp+. Around city I'm seeing about 13mpg, highway 20+.

I'm looking to swap to 3.31s for drivability.

I have 3.31s and and already average like 14 with 70% highway driving lol. How would you describe your car now to when it was stock? As in stoplight to stoplight.

My tuner says that his Paxton cars drive really well but that the TVS is more stock like for whatever that is worth...

Hmm, I see you you've had a whipple before, do you prefer the whipple or the vortech?

 

[Shaun@AED]

Piss poor Maf signal quality. Worst of all the blower setups I've done, by FAR.

A properly designed kit should not have piping transitions before the Maf Sensor. Paxton's/Vortech's have the biggest changes before and after the Maf. Even the Procharger and Hellion kits with the Maf sensor in the Intercooler have FAR cleaner maf signals. Couple that with too small of a Blow Off valve and the Maf gets VERY choppy on decel and higher RPM part throttle. We can NOT tune this out!

Let me illustrate:

Maf Signal logged from a random TVS car in my data base:

Random Whipple Car in my data base:

Random ProCharger:

Random Paxton:

Do NOT expect a Paxton to drive as good as the other setups. We do the best we can given what we have to work with. I would NOT run a Paxton on my own Coyote like this!

 

[blackbeast12]

My paxton is spot on drives like stock when I'm not in boost, beastly when in boost , idles like stock (smooth)... I have no complaints! If you get one just make sure you get a dyno tune and get it right the 1st tune! Oh and a tial bov is a must!

 

[Justin81]

Shawn,

Can you beak this down to what this actually means? I can see the line looks pretty fuzzy but what's happening? I see the other blower range from 5.0 to 5.5 and the Paxton goes 6.7. Is that MAF being "over extended?"

 

[Shaun@AED]

Shawn,

Can you beak this down to what this actually means? I can see the line looks pretty fuzzy but what's happening? I see the other blower range from 5.0 to 5.5 and the Paxton goes 6.7. Is that MAF being "over extended?"

Ignore the actual numbers.
The maf signal is all over the place with the Paxton as you are driving down the road. This results in fueling, load, and everything else the ECU uses to calculate based on Maf is rapidly changing all the time. (Trans pressure and shift points as well BTW). The ECU is constantly reading these changes and trying to adjust.

Remember, Maf is the multiplier to the airflow model. Any rapid changes in the signal WILL result in rapid changes in Injector pulse width, Ignition spark (due to load changes), Throttle angle (due to MAP changes), etc. All of which means not as smooth drivability compared to those setups that have *clean* Maf signals.

Also notice what the Maf does after you let out of the throttle (Deceleration). Maf signal goes nuts due to the small Blow Off Valve on those kits. An upgrade to a Tial is manditory IMO (if you don't want stalling issues anyway).

 

[Blazer707@TBR]

I had stalling issues with the kit at first. But after shaun tuning it mine does not stall anymore. Literally drives like stock and you would'nt be able to tell it has a blower on it unless you get on it.

 

[DSargent09]

hmnmm. Interesting. Mine drives amazingly good. No issues at all. It may be more difficult for you to tune, but to discredit driveability with a good tune seems off to me.

 

[ajpturbo]

hmnmm. Interesting. Mine drives amazingly good. No issues at all. It may be more difficult for you to tune, but to discredit driveability with a good tune seems off to me.

It may drive well but it sounds like it's at the expense of relying heavily on the ECU to make a lot of corrections and calculations unnecessarily due to bad MAF placement and geometry...The fact that you said this means you don't really understand the fundamentals of tuning...A clean MAF signal will lead to many good things as AED just described...It's not that it's more difficult to tune, but you need good data to make good tables and you simply don't get it with that setup.

 

[Justin81]

This thread just threw me through a loop with the Paxton Purchase. I wish what Shaun posted didn't make so much sense.

Why are the screw/roots style blower demonstrating such a cleaner signal? Does it have to do with the location of the blower on the motor or simply a better placement of MAF?

 

[blackbeast12]

This thread just threw me through a loop with the Paxton Purchase. I wish what Shaun posted didn't make so much sense.

Why are the screw/roots style blower demonstrating such a cleaner signal? Does it have to do with the location of the blower on the motor or simply a better placement of MAF?

Theres a ton of paxton / vortech owners here and I never heard of anyone complaining about driveability issues. But i have heard alot of concerns about heat soak with roots style blowers, which to me is more serious then any drivability concerns. I suggest you drive both types before you buy then make your decision!

 

[CPRsm]

This thread just threw me through a loop with the Paxton Purchase. I wish what Shaun posted didn't make so much sense.

Why are the screw/roots style blower demonstrating such a cleaner signal? Does it have to do with the location of the blower on the motor or simply a better placement of MAF?

It's maf placement. Air become turbulent when it enters a larger tube. But it speeds and straightens when necked down.

Theres a ton of paxton / vortech owners here and I never heard of anyone complaining about driveability issues.

Generally that because a product already has a following and people don't want to go public and be harassed by all the people who haven't had a problem. Honestly, if most customers don't feel it, they're none the wiser to the situation

 

[Justin81]

I believe your 100% correct. I haven't heard one person complain about the driveablity of these type blowers. However, What the man is saying is backed up with a very clear evidence that the computer has to accommodate a piss poor MAF signal.

My problem is that I bought the new car so I could get in at any time and drive the car like it's stock. Idling problems and problems on Decel are something I do not want to deal with. There's a good chance I may not have a "Shaun @ AED" to straighten my car out on the rollers.

 

[GHIG'13]

My Paxton car dips rpm every now and then but has never stalled out. My question would be is there anything we vortech/paxton owners can do to fix this issue???

 

[Justin81]

I suggest you drive both types before you buy then make your decision!

I'll be down after work to thrash on your car for 30 minutes. Let me know what time works for you.