24psi in all gears with the auto would have to make it real kick to drive as long as the tranny did'nt fall apart. nobody has any info for the 5spd with that kind of tune-up yet?

 

We should have some before/after dyno results shortly for the 5-speed...perhaps as soon as next week.

 

Yeah I would like to see the video of an SS pulling the said 24 psi of boost in all 5 gears and hold it. Im not buying the 24 psi deal and its only running in the 14's in the 1/4. My 05 SRT4 dynoed 330 to the wheel and Im pushing 22 psi and the car went 13.1 on stock 205 tires with a 2.4 60ft at 110. So 24 psi on an SS should put it in the 12's but the tuners are saying 14's. This is why I dont belive the numbers posted on psi.

 

Bear in mind, PSI of boost is relative to a host of factors including engine displacement, vehicle weight, gearing, turbo size...it goes on and on. Boost is really more of an effect of all these factors than a standard of comparison. As such, it's not an effective yardstick to use to compare vehicles quite as different as HHR SS and SRT-4.

 

Everything Ive read says that the SS has a bigger turbo than an SRT4 with a little bit smaller displacement engine. Weight difference is with in a few hundred pounds? If an SS is truly making 24 psi and is only running 14's Ill never buy a programmer Ill leave it stock. Thats hideous the displacement between bothe cars are so small that the psi in boost should even them out. Especially with the amount of air the SS would be moving at 24psi regardless of gearing these cars arent that far apart in gearing besides I would prefer the car with the longer gear on a Turbo car.

Boost makes all the difference on Turbo cars it makes up for lack of displacement or na horsepower. What Im saying is that who ever posted 24 psi show me a video of the SS holding 24psi through all 5 gears I dont belive it will hold 24psi.

 

show me that video Ill be waiting. I hope Im wrong because I have an SS also.

 

I'd like to add some factors to consider here. As a purveyor of SRT-4 performance parts, and the proud owner of my own 11.87 second, 122 MPH street-tired SRT-4, I can draw some effective comparisons!

SRT-4:
Curb Weight 2970 lbs.
2.4L engine
With an on-track weight of 3200 pounds, it would require 390 engine HP (332 WHP) to go 110 MPH. Something fishy there..the stock turbo will not support 390 HP.

HHR SS:
Curb Weight 3280 lbs.
2.0L engine
With an on-track weight of 3510 pounds, it would require 429 engine HP (365 WHP) to go 110 MPH. Yee-haaa!

The difference between a 2.0 and a 2.4 is large...20%, or the same difference as between a 350 and a 427 V8. Significant for sure.

The stock SRT-4 turbo is too small to maintain good boost performance at high RPM once turned up...but in no case can it support 390 HP.

In ANY case, the slightly larger turbo of the HHR, with the much smaller engine, WILL hold good boost pressure all the way to redline, unlike the SRT. Will it go low 13's like its lighter friend with the bigger engine (SRT)? Only time will tell

 

Just curious... has anyone verified that this is a genuine mechanical boost gauge? I know the DSM's and several other turbo cars have used electric "sort of" gauges to indicate general vacuum/boost rather than the more reliable mechanical method.

 

Some "pre-sales" questions for ecoboost...

1) Might you be Bill, Jr? If not, who are you and what's your role with HR?

2) For the tune, I understand your desire to marry the product to the vehicle, and assume you write back the VIN or other identifying number on first read. What happens if the user has to replace a bad or crash damaged ECM? How does he get the programmer to unmarry to the old unit and re-marry to the new one? Or is he out $1k?

3) Your web site indicates the programmer can get upgraded maps via download. So... when I go beyond a stock motor + flash, and add bigger injectors or a bigger turbo, etc., I'm ASSuming I can get prettier maps via download. Is that something that you'll offer the user free (assuming we're sticking with HR "stage xx" type of upgrades? Ex: I add your T3 turbo (or whatever)... will you provide an appropriate tune download to go with it? Or... are the tune maps adaptive enough to deal with other mods such that adding a bigger turbo doesn't just put me in a lean condition?

4) What parameters does the Ecotec use for mapping fuel curves? MAPS, TPS, speed/rpm???

5) Whoops... one more... you offer the BOV in recirculating and venting versions. You mention that some enginee management systems expect to see the recirculation of that pressure. What about the Ecotecs in the HHR? I'd much prefer the venting version... but don't want to freak out the computer because of it.

6) There is no #6... yet


I decided to ask these here as others are likely interested in the information as well. I'm getting close to pulling the trigger on a tune, but want to make sure I have an additional upgrade path without re-spending a lot of money.

Thanks in advance.

 

This aspect has come a long way since those old DSM's that 'calculated' boost from MAF readings. While it is in fact an electronic gauge, it's rather accurate on the HHR.