PT dyno chart and thoughts on tuning

The Apex'i Super AFC isn't the only Fuel Computer on the market.

The HKS Super AFR has a better idle control circuit and is just as easy to tune as the AFC, just doesn't have the fancy display and might be a good idea for those worried about your AFC getting stolen.

Also you might wanna look into the Greddy E-Manage or Perfect Power's SMT-6 - www.perfectpower.com

They have installed them on Neons and Vipers with great sucess and you have more tuning options than available with the Super AFC.

You almost might look into shooting the intercooler with CO2 or injecting nitrous oxide for intercooling and additional horsepower. Nitrous Express has the N-Intercooler and I sell them.

[Gary C]

The thing with adding nitrous to the intercooler is you not only get the nitrous but you're also getting a few extra lbs of boost as well, due to the much denser charge of air, and the effects of the nitrous on the motor and the wastegate not being completely up to the task.
I've played with nitrous kits on 1.8T motors and they usually get about 3lbs more boost on nitrous than they get off the nitrous, if your inject it into the motor, rather than just doing a spray bar setup to 'freeze' the intercooler if you will. Plus you always have to bank on there actually being nitrous in the tank. For *MY* application nitrous oxide injection is not the route i will be going for many reasons.
There are ins and outs to both setups, but i'm going with what *I* know, that being a water injection system, (pretty far off in the distance) such as the one from www.aquamist.co.uk. I've had *GREAT* luck with that setup and it's charge cooling ability.
as for other AFC's that is a very good point. But for right now i have an AFC from a prior car that will be going in. until there is a setup like the LINK ecu or such out where it's a plug and play piggy back controller that the end user can actually tune with the right software/interface hardware

[PT Eric]

Gary I think it's great all the power you are getting at the wheels with the stock GT. One thing I do not understand though is how can it be that you do not have any loss from the flywheel to the actual wheels when it comes to the torque rating for the stock GT?. DC advertises 244lbs of torque for the stock GT and you indicate you are getting 248lbs? That's 4 lbs more than DC advertises and you indicate it's at the wheels yet DC's rating is based at the flywheel. How can your torque be higher at the wheels for a stock GT than the torque rating from DC for the floywheel?

The horsepower sounds more reasonable, however, even that seems so high because usually there is at least a 10-30 percent loss (depending on transmission type) from the flywheel to the wheels. Your HP indicates 209 yet DC advertises 215hp. Your 209hp is less than a 10% loss at the wheels, whch makes your HP rating seem somewhat high for a stock GT. It's not that I question you it's that I wonder about the accuaracy of the dyno reading and wonder about DC's advertised hp and torque ratings (maybe DC is advertisiing way way below what the flywheel hp and torque actually are). Well good luck and enjoy your GT.

[Gary C]

it's been proven that DC under-rated the motors in them.
I posted the SAE corrected readings as well which are generally a little bit lower. As far as the dyno's yes each dyno does read a bit differently. The shop i dyno'd at is a VERY respected tuner in the world of Eclipse/Talon/Lazers, and all things turbo. They have the fatest street driven Galant VR4, along with *MANY* insanely quick street cars (we're talking sub 11's and some sub 10 second cars that are street driven)
It was common for DC to underrate the motors back in the hey days of muscle cars as well so this really goes along with what they are doing with the SRT and GT in trying to corner the market and take it in one fell swoop for them *hopefully*.
at the flywheel using 18% loss... I have ~245HP and ~290lb feet of torque. Which beleive it or not does feel right, based on the PT's girth and how it gets pulled around by this motor.
The PT pulls like it does have that much power. From 60-90 and beyond it feels like there is a giant hand pushing you from the back side and the car just keeps pulling. It's amazing how much oomph this little motor is producing.
I've talked with many SRT owners who have dyno'd and they put down in the realm of 220-224HP at the wheels, and around 245lb feet of torque, STD corrected. SAE numbers are generally down by ~5HP from most once you factor in the corrections.
Each dyno does vary, but If you ever get a chance to drive a broken in GT cruiser definatly do it. It's a blast. It pulls just as hard as my Stock stripper Mustang LX 5.0 did!

Thank you much for the wrods and have fun with your PT!!

[bstockum]

Most may have seen my chart before.
Mine was done at a fairly constant 12 psi, (it did drop off a little)
The interesting thing when comparing these two charts is the torque of the GT stayed flat. On the HRC PT the HP stayed flat.

The graphs are diff scales, so keep that in mind when visually comparing them. I tried to streach mine a little to even out the scale some. This is an early chart, that closely mayched the HP and TQ ot the new GT, ... so that is why I chose it.

We are now more than 50 WHP above that level, (Brads chart).
Soon we will have some new dyno charts to display, ... so this should be some fun, ... to see how we can compare to the factory HP numbers. We haven't dyno'd Al's car yet, ... but can hardly wait to see his numbers considering the HRC,PT's ... real-time performance against a new GT.




I wonder if you should find the signal line that goes to the ECU and put a small regulator on it to keep it from seeing more than 13 PSI of boost? Wonder if this would give you a better "window" that you could work within?

Bob

[Gary C]

very interesting to see the two charts next to each other.
Boost on my GT diped from 4500-redline and stabilized itself at 9psi through redline where you were showing 12psi with a silght tapering of the boost correct?
I'll have to dyno with just a MBC at 12psi and see how that makes a difference and once that is done I'll definalty post that up here, along with one at 14psi, and one with the exhuast and AFC once hooked up.
As for the regulator, we're actually going to toy with that once we get to the point of hooking it up and dynoing it with the MBC at 12 and 14PSI with an OBDII scanner/loger hooked up to see how severly it retards the timing, if it will be reacting anything like the WRX ecu does.