SRT Chat HERE on March 18th!

[JonB]

Is this graffiti for real, or do you guys have autograph-decals now:

 

[SRT Engineers]

Another quick question:

Is there any breaking advantage of changing the factory Brembo Calipers to StopTech Calipers to "match" the StopTech rotors on the ACR?

We have not tested the Stoptech calipers. When switching calipers, you need to watch piston areas and displacement volumes to make sure the brakes are well balanced and that you don't run out of master cylinder volume. Proceed carefully.

 

[Grailkeeper]

Hi & thanks for doing these little "chats"!!!

I have an `09 ACR.

Question 1:
I'd like to put the front splitter piece in. I was wondering if I should drop the rear wing from the stock #2 position to maybe position #3. I drive on the street and really do not want to drop the ride height.

Question 2:
How many `09 ACRs have rolled off the line (Herb was looking into this as well).

Thanks!!!

Fast....
I'm working on the ACR answer...stay tuned....GK

 

[SRT Engineers]

Good evening.

1. Any news on the window regulator issue we have previously chatted about? I have had two driver's side regulators replaced and one BCM and it still occassionaly fails to drop. It has been properly trained.

2. Please discuss the benefit or detriment of using five gallons of 98 octane race fuel mixed with 93 octane fuel at a track day. In a stock car and in a car with a Paxton kit.

3. Have you had a chance to try out the MGW performance shifter mechanism yet that we mentioned the last time? It really is a significant improvement.


Regards,

Bob

Bob, how’s the Jeep?

1- If your issue is the glass clicking against the roof when you open the door, it may simply be caused by opening the door too quickly (the glass needs time to drop). It can also be caused by pulling hard enough on the door release lever that it goes beyond the normal electronically activated position and into the mechanical override. If, on the other hand, your issue is the glass contacting the roof when you close the door, check with your dealer to make sure your BCM has the latest flash. There was a change that addressed an issue with the window going too high if it was raised with the door open. The only other thing we can think of is the door latch itself. The latch senses if the door is closed, initiating operation of the smart glass and allowing the BCM to learn the up position of the glass. If that latch sensor is not working properly, it could affect the learn (although we have never heard of a bad latch sensor).

2 – Mixing race fuel with pump fuel will result in a higher octane rating. In general, the lowest octane required is the best to use for a couple of reasons – cost and probably slightly more energy in the lower octane fuel. In very hot and/or dry conditions at sea level, you could experience some burst knock with 93 octane fuel so a higher octane will prevent this without a performance loss (the knock sensors will pull spark when the knock occurs). With a blower, the octane requirement must be significantly higher; the highest octane available would be smart.

3 – We have not tried the MGW shifter in any of our development cars. Some of us have driven Ralph Giles car with the shifter. I’d say it’s a matter of personal taste (some like it, others don’t) but we are considering a shorter shifter for production or as an option.

 

[SRT Engineers]

Hi & thanks for doing these little "chats"!!!

I have an `09 ACR.

Question 1:
I'd like to put the front splitter piece in. I was wondering if I should drop the rear wing from the stock #2 position to maybe position #3. I drive on the street and really do not want to drop the ride height.

Question 2:
How many `09 ACRs have rolled off the line (Herb was looking into this as well).

Thanks!!!

1) The stock wing position was determined through track testing with race ride heights and splitter extension installed. That configuration provides a balanced handling setup under most track conditions. We do not recommend changing from the stock wing position, because it has a dramatic affect on handling. You must have a good feel for the car and a large respect for aerodynamic effects before tampering with this component. For street driving, we do not recommend the splitter extension. It puts your splitter at risk from curb hits, speed bumps, etc.

 

[Grailkeeper]

Is this graffiti for real, or do you guys have autograph-decals now:

Hi Jon...

You just want to get into the decal business....don't you....GK

 

[FastZilla]

Thanks for the answers!!! I got what I needed. I LOVE my Viper - you guys ROCK!!!!!

 

[SRT Engineers]

The first time I had the problem, it was on cylinders #3 and #7 (I think that's the numbering, the second and fourth cylinders on the driver's side). #3 was bent like crazy, and #7 was just bowed. Recently, I heard a tapping sound, so I pulled the valve cover, and #1 exhaust (first cylinder on driver's side) was slightly bowed. I'm the original owner and it is indeed stock.

What is a little strange is that when I originally took delivery of the vehicle in '97, I took it back to the dealer because I was hearing a slight tapping coming from the driver's side valvetrain. He just told me that the injectors make a ton of noise and I was probably just hearing that. Now, after replacing those pushrods, no more tapping...

Martin – Sure sounds like something is wrong with the odd bank. Now that you have replaced the bent pushrods have you had any that re-occured (in the same spot)?

 

[SRT Engineers]

question on 1997.......occasionally the idle will not come down to normal, and remains above 1,200 rpm, when the clutch is in. occurs when moving and not moving. what could causes be on that?

That is likely due to the AIS servo getting sticky and loosing steps... Thats the bypass idle air servo motor. If the servo gets sticky it can loose steps, and over time looses track of it's position. A battery disconnect will force an AIS reset, if the car works normally after a reset, it is loosing steps.

If you have changed the mechanical stop on the throttles at all that too can effect things... or if you've used aftermarket throttle bodies.

 

[Bobpantax]

Bob, how’s the Jeep?

1- If your issue is the glass clicking against the roof when you open the door, it may simply be caused by opening the door too quickly (the glass needs time to drop). It can also be caused by pulling hard enough on the door release lever that it goes beyond the normal electronically activated position and into the mechanical override. If, on the other hand, your issue is the glass contacting the roof when you close the door, check with your dealer to make sure your BCM has the latest flash. There was a change that addressed an issue with the window going too high if it was raised with the door open. The only other thing we can think of is the door latch itself. The latch senses if the door is closed, initiating operation of the smart glass and allowing the BCM to learn the up position of the glass. If that latch sensor is not working properly, it could affect the learn (although we have never heard of a bad latch sensor).

2 – Mixing race fuel with pump fuel will result in a higher octane rating. In general, the lowest octane required is the best to use for a couple of reasons – cost and probably slightly more energy in the lower octane fuel. In very hot and/or dry conditions at sea level, you could experience some burst knock with 93 octane fuel so a higher octane will prevent this without a performance loss (the knock sensors will pull spark when the knock occurs). With a blower, the octane requirement must be significantly higher; the highest octane available would be smart.

3 – We have not tried the MGW shifter in any of our development cars. Some of us have driven Ralph Giles car with the shifter. I’d say it’s a matter of personal taste (some like it, others don’t) but we are considering a shorter shifter for production or as an option.

Hi. The Jeep is fantastic! In fact it is so fantastic, it is still stock. People still come up to me and say: "That must have cost you a fortune to make it look and perform like that". I laugh and tell them it's stock.

The Viper window issue is only when the door is open and I go to close it. It only very rarely occurs now. The Viper Tech suggested that I peroiodically retrain it. Since it has not done it since the last retraining, maybe it just has a mild learning disability. LOL.

 

[SRT Engineers]

Hi. The Jeep is fantastic! In fact it is so fantastic, it is still stock. People still come up to me and say: "That must have cost you a fortune to make it look and perform like that". I laugh and tell them its stock.

The Viper window issue is only when the door is open and I go to close it. It only very rarely occurs now. The Viper Tech suggested that I peroiodically retrain it. Since it has not done it since the last retraining, maybe it just has a mild learning disability. LOL.

If the issue is only when the door is open and you go to close it, definitely check to make sure you have the latest BCM flash.

 

[SRT Engineers]

Thanks everyone! Have a good night!

 

[JonB]

Jack Time.

Bye and Thanks !

 

[Bobpantax]

Suggestion. There is still some comparatively inexpensive land not that far from Homestead Speedway. Miami Dade County and the City of Homestead would probably both provide some tax and other goodies for locating a Viper plant in that area. You would be able to drive the Vipers all year round. Fresh stone ***** and Florida lobster would be available. South Beach is not that far away. Sounds like a perfect place for the New Viper Enterprise - yes?

 

[Mopar Boy]

Thanks again for your time and knowledge guys (and gals!)!



Robert

 

[Martin]

Martin – Sure sounds like something is wrong with the odd bank. Now that you have replaced the bent pushrods have you had any that re-occured (in the same spot)?

So far, it's been fine and seems to run great. i need to do a really thorough compression test on it to see if any of those valves did hit anything - but so far it seems fine. I tested the compression with an old (and somewhat flaky) compression tester the first time the problem happened, and compression was even. Now that I have a much better tester, I'm going to re-test and see if I have bent or nicked valves (hopefully not).

About the only thing that happened to the car immediately before the pushrod problem started is that my power steering pulley grenaded and the engine got pretty hot (but I shut down once I was safely off the road and the needle just got into the red zone). No leaks since, no water in oil, no oil in coolant, so I don't think anything warped or blew out. I can't see how that would cause a problem, but thought I'd throw it out there just in case.

Really appreciate your help with this, and with everyone else's questions!!

 

[Y2K5SRT]

Thanks again!

 

[Marv S]

Thank you. I'll check that out.

Much appreciation for your time and expertise.

That is likely due to the AIS servo getting sticky and loosing steps... Thats the bypass idle air servo motor. If the servo gets sticky it can loose steps, and over time looses track of it's position. A battery disconnect will force an AIS reset, if the car works normally after a reset, it is loosing steps.

If you have changed the mechanical stop on the throttles at all that too can effect things... or if you've used aftermarket throttle bodies.

 

[HI-NOS-Viper]

Awesome that we have a club that have the Engineers come and answer questions for us. This truly is great. Thanks SRT.

 

[bmw2nv2000]

This is a really cool thread