I have been switching back and forth between the factory and 90mm throttle bodies. Without a doubt there is a throttle and acceleration difference between the two. The 90mm with my 426 set up definetly makes a difference and is far more responsive and wide open throttle power seems to explode. The drivability and idle quality is also definetly nowhere as good as the factory unit. Cold morning starts are plagued by hunting/surging and throttle blade chatter. Tuning this monster in will be the problem in the future, especially since this is a new product to the industry. Also the mating surfaces between the throttle body and factory manifold may be an issue since the surfaces do not match up.
Which one are you playing with......I have both the LM and the Arrington and I like them both for different reasons.
Really......mating issues?I didn't find that at all........I also didn't have the cold start issues.Could this be another WK-LX thing?
This is the EXACT challenge I am having right now. Surging and what not. Although I had my extrude honed manifold port matched to it, so I'm good there. But if you find a fix Stanko, let me know. Andy and the PPP tuners are trying to find me a fix right now. Good luck man! I know you gotta be loving the new setup, I'm like a kid on Christmas right now too! Chase
Chase, PM Nathan (Redfox). He had the dual TBs way back and worked out a number of problems with them. One of them was going into limp mode after about 2 hrs on the highway.
Chase I'll keep in touch about. Mine "hunts" at start up and the Arrington TB makes a rattling sound and then causes the motor to miss and shake during, once warm and I take off it will surge until it is in operating temp.
Mine surges at red lights and whenever I'm stopped mainly. It's like it doesn't "adjust" the airflow from throttle to throttle or something?! If that makes any sense.... Chase
Mine does as well. I raised the idle 50rpm at a time and it helped quite a bit. I reinstalled the stock throttle body tonight until I know my VE's are right. I think alot of this has to do with the cam overlaps. There is a reason the factory cam is retarded 11 degrees.
Question Hemi 31???? Eric I just read your write up. The Arrington is massive. As a matter of fact the stock TB fits loosely inside it..lol!! There is no doubt that the larger throttle body provides a more explosive acceleration. Everytime I reinstall it and I go 1/2 throttle or more it seems to have a "whistle" sound generated from the intake of air. I have a question. Have you experienced a cold start surging with a rattling sound seeming to come from the throttle body?
The factory unit has two TPS sensors located within the unit. I hope both these aftermarket TB's are the same, that would make tuning possible via CMR. If they are using one TPS sensor from .5v to 5v this will be a problem. If I'm not mistaken the factory unit is .5v to 1v for the idle TPS and 1v to 5v for the driving TPS. I'll double check tomorrow but I think it's this way from the factory. On a factory 6.1L with a good CAI I have seen only .25 to .50 inches -HG on the dyno at WOT. This is good and acceptable. With a dual CAI setup I've seen 0 HG's. I'll be really curious to see a gain from the 90mm if both TB's are at 0 HG. On sidenote a single blade TB for a Lightning SVT was worth a mere 4 rwhp over a factory dual 58mm. Food for thought.
No I haven't.Mine is very smooth on cold start.no issues at all.As a matter of fact the only issue I had was the limp mode.Up until then it was as nice as stock. Heres a question......when did you get your TB?Is it one of the older versions or a new one?
The GM TB won't require retuning because the throat of the TB has a bore extension that meters the air at close to stock settings at lower TPS positions. This is a key element that's missing with the Arrington unit. Question is, have you been able to measure any gains with the GM 90mm TB?
