Paxton Power On/Off

[rottenronnie]

I have a buddy with an '05 QC and a Paxton S/C.

He says it is a 5 p.s.i. system and, when it is working properly, the truck runs a low 13 at 106 m.p.h. here in Calgary. Then he will make a run and it drops to a high 13 at 100 m.p.h. (or less) like it isn't making any boost at all. Unfortunately, he doesn't run a boost gauge. It either runs reasonably hard or it doesn't. At a lower altitude it will run 110 but, on the next pass, 103. On the next pass, 110 etc. It isn't a tire spin situation.

I am not familiar with the Paxtons.

Any ideas or where to look??:dontknow:

Thanks!

 

[Dave T(BADVENM)]

I didnt know they made a 5 psi system. Without a boost or aem a/f gauge one really cant help the guy. Where did he get it tuned...if at all?

One possibility is a vacuum leak through a disconnected hose or one that may have a small split in it, allowing boost not to always build.

 

[rottenronnie]

I didnt know they made a 5 psi system. Without a boost or aem a/f gauge one really cant help the guy. Where did he get it tuned...if at all?

One possibility is a vacuum leak through a disconnected hose or one that may have a small split in it, allowing boost not to always build.

I didn't know they made a 5 p.s.i. system either. I am only going on what he was told when he bought the system and this info was passed onto me etc; etc. IF it is a 5 p.s.i. system and decided to build boost, it would only get around 3 p.s.i. at our altitude anyways, and would explain the 106 m.p.h.

The ECU was supposed to have been flashed by "someone" in California.

I shouldn't be beating up on him with my NA QC.

 

[Silverback]

Installing any type of FI system and not adding gages is not smart in my opinion.

 

[rottenronnie]

Installing any type of FI system and not adding gages is not smart in my opinion.

Agreed.

I sounds like he paid good money for the system too; but I really can't help him much without knowing what is happening during the run.

 

[Ram From Hell]

I have a buddy with an '05 QC and a Paxton S/C.

He says it is a 5 p.s.i. system and, when it is working properly, the truck runs a low 13 at 106 m.p.h. here in Calgary. Then he will make a run and it drops to a high 13 at 100 m.p.h. (or less) like it isn't making any boost at all. Unfortunately, he doesn't run a boost gauge. It either runs reasonably hard or it doesn't. At a lower altitude it will run 110 but, on the next pass, 103. On the next pass, 110 etc. It isn't a tire spin situation.

I am not familiar with the Paxtons.

I doubt that a 7mph difference in trap speeds could be attributed to making boost and not making boost. His time between passes will make a significant difference in power output though, due to the degree of heat soak at the time. I'd be willing to bet that he's losing upwards of 30rwhp if he's hot lapping.

I'm guessing that if he hasn't even bothered to install a boost gauge that he probably has not upgraded the Paxton's heat exchanger. Between Boomer's upgrade and a larger coolant tank, you can almost eliminate heat soak. Alternately, he could do a quick/cheap Roe meth kit to help with that.

I didnt know they made a 5 psi system. QUOTE]

The kit comes with a pulley that should make about 5psi on an otherwise stock setup (without belt slippage, that is).

 

[RatMotor]

Stock tranny? Could be starting to slip as it heats up.

 

[Dave T(BADVENM)]

I didn't know they made a 5 p.s.i. system either. I am only going on what he was told when he bought the system and this info was passed onto me etc; etc. IF it is a 5 p.s.i. system and decided to build boost, it would only get around 3 p.s.i. at our altitude anyways, and would explain the 106 m.p.h.

The ECU was supposed to have been flashed by "someone" in California.

I shouldn't be beating up on him with my NA QC.

I can build 8psi of boost at 6000 feet on the stock system...altitude doesnt have anything to do with it I dont think. Maybe its a Paxton Novi-1000 instead of the 2000?

 

[KRAZYSRT10]

Damn it!!

You guyz are killing me with all this talk of Paxtons...I had just decided to go with the Roe and now here I am back on the Fence!!!!KRAP!!!!!!!

Off to start another thread...

 

[Nowwhat]

the paxton is 8psi Stock....

agree with R from Hell.....hot lapping without meth or a bigger exchanger can do it for sure....

 

[Hamrhead]

Belt Slippage maybe???:dontknow:

 

[Silverback]

Belt Slippage maybe???:dontknow:

Without gauges we can guess all night and still be wrong.

 

[QuickSilver]

HEAT-SOAK!

Had it for a while, until we changed a few things for the better :rock:
You don't need no gauges to know heat-soak...

Quick

 

[rottenronnie]

I wish it was something as simple as heat soak.

It doesn't seem to matter if it is the 1st or the 10th back to back run.
It either pulls like it has a supercharger or it doesn't.

Thanks for the replys.

Ron

 

[rottenronnie]

P.S. Is that all these S/C vehicles will do- 106? 110 M.P.H.? That is only 80
or so horsepower more than my NA QC makes; not 175+ more, like advertised...:dontknow:

 

[Dave T(BADVENM)]

What altitude are you running at? At 5700 feet with a density alt of over
7300 ft I ran my 111 mph run. Take my truck to sea level I should be pushing 120+ mph.

 

[rottenronnie]

What altitude are you running at? At 5700 feet with a density alt of over
7300 ft I ran my 111 mph run. Take my truck to sea level I should be pushing 120+ mph.

We are at 3750 but DA was 5750, as it often is here, when he made his 106 M.P.H. run. My concern is, my NA truck with just a couple of minor mods was "only" 6 M.P.H. behind which does not equal the 420 r.w.h.p. NA and 620 r.w.h.p. S/C, as often advertised.

I would expect his truck (with the Paxton) should be running harder than it is...
A few members have posted in that 110 M.P.H. range which is where my buddy's runs at the 2500 altitude mark. I don't think in his case he would pick up another 10 M.P.H. dropping right to sea level.

It must be in the tuning...

 

[Ram From Hell]

the paxton is 8psi Stock....

QUOTE]

Huh. Maybe that's with stock heads.

 

[Dave T(BADVENM)]

We are at 3750 but DA was 5750, as it often is here, when he made his 106 M.P.H. run. My concern is, my NA truck with just a couple of minor mods was "only" 6 M.P.H. behind which does not equal the 420 r.w.h.p. NA and 620 r.w.h.p. S/C, as often advertised.

I would expect his truck (with the Paxton) should be running harder than it is...
A few members have posted in that 110 M.P.H. range which is where my buddy's runs at the 2500 altitude mark. I don't think in his case he would pick up another 10 M.P.H. dropping right to sea level.

It must be in the tuning...

I will add I gained nearly a full second after installing DC Performances blower flash. When they removed the wide open throttle timer delay the truck really wakes up right off the line!! That was well worth the money...I had the boost for mid to high rpms but the truck was falling on its face at the line.

 

[tinygiants]

the paxton is 8psi Stock....

agree with R from Hell.....hot lapping without meth or a bigger exchanger can do it for sure....

Not saying he is not suffering from a mech issue, but it could be because of a poor launch. I saw as much as a second diff because of launch technique. I was a second faster due to better launches. Yes that was on a hot (200 F) truck as I was darn near hot lapping by the end.

My biggest problem was bogging down. A ROE makes power earlier than a Paxton, so if he is bogging at all, it will take a small slice of time and track to build back up.