Paxton fuel requirements

[mamba]

Hi I am about to run a Paxton supercharger with meth injection on a viper srt10, what is the best size aftermarket injectors to run and at what fuel pressure.
I am planing on running around 10 pounds of boost as I know the cream puff motor does not like to much.
Any help would be appreciated.

[Viper]

these guys will know what you need
http://dcperformanceonlinestore.com/

[N GTS]

Stock fuel pressure is at 55 psi, unless you remove it from the tank module and put in your own lines and an adjustable regulator. The stock system is good to safely supply for boost of 5 psi. The OE Gen3 rods are weak, I wouldn't go anywhere near 10 psi, and expect a stock engine to hold out!

[stevieturbo]

mamba said:

Hi I am about to run a Paxton supercharger with meth injection on a viper srt10, what is the best size aftermarket injectors to run and at what fuel pressure.
I am planing on running around 10 pounds of boost as I know the cream puff motor does not like to much.
Any help would be appreciated.

Of more importance is how exactly are you re-tuning to ensure safe running after the upgrade ?

You ideally size injectors for your power goal and to remain less than 80% IDC at full load.

Fuel pressure is entirely up to you....but do you even have the means to adjust it ?

[mamba]

I am looking for 800 hp at the flywheel, the plan was to drop the charge cooler and run a front mounted intercooler to reduce heat soak along with meth injection to reduce the risk of detonation.
Aero motive fuel pump,regulator and new fuel lines to take care of the fuel supply.
De cat exhaust without the crossover.

Is it possible to use an SCT tuner to remap the ECU I am sure I have read that a company's in the US do custom tunes for the viper.

[Viper]

800, sounds like youve a lot of research to do

http://dcperformanceonlinestore.com//gen3.html?pag...

[Dr-Bob]

Speak to DC Performance or Roe racing as they both do SCT tunes.....

[ViperPict]

mamba said:

I am looking for 800 hp at the flywheel, the plan was to drop the charge cooler and run a front mounted intercooler to reduce heat soak along with meth injection to reduce the risk of detonation.
Aero motive fuel pump,regulator and new fuel lines to take care of the fuel supply.
De cat exhaust without the crossover.

Is it possible to use an SCT tuner to remap the ECU I am sure I have read that a company's in the US do custom tunes for the viper.

I'm going through pretty much exactly the same process now on my RT/10 and have done lots of reasearch on the options. The Paxton kit has fuel pressure at 100psi on full boost (although you appear to be going for a further and more versatile fueling upgrade - good move I think). I'm using 50lb injectors.

But mapping the car is the issue. I WOULD NOT TRUST SCT FLASH TUNES FOR 800BHP!!! You need the car properly mapped 'live', preferably on the road/ track. I'm using a modified Split Second controller that allows timing and fueling to be mapped plus takes in two additional signals (WBL AFR and knock). It's still a 'piggy back' system so not ideal. If I had the money I'd be going MoTec.

Also consider an aftermarket 'heat exchanger' rather than an intercooler - the latter will give you a plumbing headache for not much benefit over the former.

[oxam]

ViperPict said:

But mapping the car is the issue. I WOULD NOT TRUST SCT FLASH TUNES FOR 800BHP!!! You need the car properly mapped 'live', preferably on the road/ track.

To be honest not sure how good the viper ecu is, but I have sct flash tune on my mustang and I have safe 580 bhp from 4.6l engine. It's all down to the person making the tune - I got mine from JDM and was a bit scared about the outcome even though they are well known mustang gurus. Did two dyno sessions and recorded quite a few parameters and they were spot on. Maybe just a touch on the safe side but don't want to risk it for the sake of 10 bhp.

My point is that you can get a very safe SCT tune from DC performance, put the car on the rolling road, log all the data with Advantage III and send them back the outcome. 10 min later they can email you a new tune and so on till you have it spot on.

[ViperPict]

oxam said:

ViperPict said:

But mapping the car is the issue. I WOULD NOT TRUST SCT FLASH TUNES FOR 800BHP!!! You need the car properly mapped 'live', preferably on the road/ track.

To be honest not sure how good the viper ecu is, but I have sct flash tune on my mustang and I have safe 580 bhp from 4.6l engine. It's all down to the person making the tune - I got mine from JDM and was a bit scared about the outcome even though they are well known mustang gurus. Did two dyno sessions and recorded quite a few parameters and they were spot on. Maybe just a touch on the safe side but don't want to risk it for the sake of 10 bhp.

My point is that you can get a very safe SCT tune from DC performance, put the car on the rolling road, log all the data with Advantage III and send them back the outcome. 10 min later they can email you a new tune and so on till you have it spot on.

Will you be able to log WBL AFR though and send that data to them? And I'd prefer the car mapped under real-world conditions (i.e., on the road/track)...

[oxam]

yup, SCT can log wideband AFR. I get your point but I think that the tune can be done on rolling road and if you really want to have it "live" you can just have a skype session with the US guys - and they can use a remote client so they can take over the laptop in the UK and do real time adjustments. I am just proposing it as an alternative and I am not saying it's better. (it was suggested to me by JDM for my mustang but at the end the mail tune was good enough)

[ViperPict]

oxam said:

yup, SCT can log wideband AFR. I get your point but I think that the tune can be done on rolling road and if you really want to have it "live" you can just have a skype session with the US guys - and they can use a remote client so they can take over the laptop in the UK and do real time adjustments. I am just proposing it as an alternative and I am not saying it's better. (it was suggested to me by JDM for my mustang but at the end the mail tune was good enough)

I'm not that familiar with Gen 3s but do they have a WDL standard?

[N GTS]

Hamish lives in the far North of most thin O2 I had to do some real time tuning for Knockhill racing with Neil sat passenger seat reading out my AFR, once Colin had shown us where to drive, LOL...but got the VEC2 dialled in OK (thanks Neil and Colin)! SCT is a step above the VEC IMMOP! Use the SCT base map and get the tuner software to dial it in. Well done for doing it yourself, ie not shed loads of cash wedge to a top tuner! The Viper ECU is pretty good and very reliable. SCT cracks that access barrier over the lesser piggy-backs.

[mamba]

After some research it seems a relatively safe 750-800 hp (flywheel) is achievable with the following modifications.

69lb injectors
Dual Walbro 255 fuel pump upgrade and fuel lines.
Boost referenced fuel pressure regulator
Larger dual pass charge cooler
Meth injection to increase the octane and reduce the chance of detonation
7.5-8 psi boost
Borla exhaust without cats
SCT tuner with recalabrated tune after dyno runs.
And a possible cam change.

[ViperPict]

mamba said:

After some research it seems a relatively safe 750-800 hp (flywheel) is achievable with the following modifications.

69lb injectors
Dual Walbro 255 fuel pump upgrade and fuel lines.
Boost referenced fuel pressure regulator
Larger dual pass charge cooler
Meth injection to increase the octane and reduce the chance of detonation
7.5-8 psi boost
Borla exhaust without cats
SCT tuner with recalabrated tune after dyno runs.
And a possible cam change.

Do you need 69lb injectors due to lower fuel pressure compared to standard Paxton kit (100psi)? I'm also keen on upgrading to the other components of your fuel system!

[mamba]

This looks like an interesting solution from Roe Racing.
I tells you all the information you require.

http://www.roeracing.com/ProductCart/pc/viewPrd.as...

[mamba]

Next most important question who would you trust to dyno the car after the conversion?
Preferably someone north of Sheffield.

[oxam]

mamba said:

Next most important question who would you trust to dyno the car after the conversion?
Preferably someone north of Sheffield.

btw. there is somebody selling a fuel setup on the viperalley - 1000cc injectors plus injector drive box, lines, rails, fuel hat for two walbros etc. for 900 usd or so.....sounds like a good deal