Well Arrington enlongated the blade design to more closely match the stock throttle body flow values. This is a major help for idle and low/part throttle opperation. Now if the GM unit has this bore extension feature, please explain to me how it works???. Steve, sounds to me like you may have other issues with your paticular unit. If you get a chance during a cold start up, grab yourself a can of starting fluid and spray it around the throttle body and see if you have some minor vacuum leak. Something everyone should consider with the Arrington. This unit untilizes the stock internals. Now, this little task may seem simple to anyone that has not dissected a stocker. But it's not as easy as it sounds. And BTW, both of your guys problems with idle/closed loop opperation can be tuned out. We did it with my duals. Also after once these tables are changed, the issues that occure during cold starts will go away after the adaptives do their part.
When GM went from the 75mm to 90mm TB in the 2005 LS2, they had to make sure that the airflow values at 5-20% throttle position were very similar to those of the smaller TB. To do this, GM extended the bore in front and behind the blade to maintain the lower airflow numbers at lower throttle blade positions. Since a 90mm TB has 44% more area than a 75mm TB, you run the risk of flowing 44% more air for the same throttle positions without making some physical modifications. This is what GM did and is one of the reasons why the LM Speed unit is more of a plug and play throttle body. The airflow at 5,10, 15 and 20% TPS more closely match the airflow at 5,10,15 and 20% TPS of the stock 6.1L Hemi TB. Early aftermarket GM 90mm throttle bodies had the same tuning issues the Arrington 90 is suffering currently. Further development will cure this problem. They just need to match the low TPS flow of the stocker.
I assume that Patrick is referring to this unit Steve: http://www.lmspeed.com/index.asp?PageAction=VIEWPROD&ProdID=75 Reese
Yes, that's the one. From what I understand, LM speed re-flanges the TBs to bolt up to the 6.1 manifold. The ID of the 6.1 intake is smaller than the TB so for best gains, you'll want to open up the 6.1L manifold throat to match the bore size of the GM 90mm TB. Pretty cool that you don't have to monkey around with swapped motors or sensors. Everything (electronics-wise) is unmolested and 100% factory.
It Works!!! Well I went back to Irwindale tonight and reinstalled the stock throttle body.....well it looks like the 90mm tb was worth like 2/10 and 2mph!!!
help my throttle body is making the cars throttle seem like a tinny touch is wide open throttle and it stays at what ever rpms u let it off at
Who's doing your tune??. Sounds to me like they have the tip-in set very high. And then when your at speed, I bet you'll find that if you let off, it wants to idle at 1100RPM and maintain speed. Do you have to brake in order to slow down?.
sorry the first post was rushed on my phone while we where tyring to tune te car. THis is what happens if you barly touch the gas the rmps shoot sky high. while driving if you touch the gas and the let off completly the rpm's stay where they where when you let your foot off. there is also a huge dely in shifts and they shifts are firmer than I have ever felt in my car almost to firm. Also if I put back on the stock TB the car doesnt idle for shit and surges really bad( due to my big ass cam) any idea are welcome at this point I just want my car back and for it to run right
I don't know who's tuning your ride big guy. But they don't have a clue what their doing. I can bet ya they are messing with the air flow tables, have your tip in completed wacked and the TM tables are jacked too. That or you got a vacuum leak and they don't know it and continue to try and make up for it with the tuning. :whistle:
