2.4 t-smec rev cutout - launch control?
I'm helping a friend with a 2.4 swap in his rampage. We went with the cam mounted distributor setup and used the 2.4 t-smec tpl file from Rob's collection (thanks Rob!). The engine fired right up and idles fine with good a/f ratio. It also revs fine in neutral and everything looks and sounds good. However, as soon as you put it in drive and give it any throttle, it feels like the engine is hitting rev limit cutout.
He's running an auto with a 3500 stall converter, so the car barely moves because it's hitting cutout right around 3000 rpm. However, this is a twin engine rampage, so we were able to used the front engine (2.2 T2 motor that runs great) to get it up to speed and around 25-30 mph, the cutout issue seems to go away on the 2.4 motor and it runs smooth.
When I set up the cal, I tried to turn all of the special items (launch control, check engine flash, etc.) off just to keep it simple. I just looked through the cal and launch control definitely seems to be turned off, but maybe I'm missing something. Has anyone run that 2.4 t-smec cal with success? I thought A.J. was running it in his 2.4 van, but I just looked through a ton of threads and can't seem to find any place where he talks about that cal.
Any assistance would be greatly appreciated!
Jon
Re: 2.4 t-smec rev cutout - launch control?
I had a similar issue at SDAC23 in Slug with a Turbonator cal. There was some hidden issue with that version # it was based from.
Be sure you are using a v19.6 based cal. I can't remember which version # it was that had the issue though. I'll try to see if i can find that old file...
Re: 2.4 t-smec rev cutout - launch control?
Yup - using the latest revision. No need to go digging Wayne - I woke up in the middle of the night last night and thought: Limp Mode!
I haven't experienced limp mode in 15-20 years, so the symptoms were foreign to me yesterday. Plus, the back motor has no connection to the dash so no check engine light to tip me off on what was going on. Before we took the ride, I noticed there was a code for the baro sensor (61) and one for the map (13). I found the baro plug was dangling there and plugged it in, but never cleared the codes. I'm guessing that even though I believe I fixed the problem that caused the codes, they were still stored and we were running the motor in limp mode.
I'll take a ride over there tomorrow and confirm. I'm hoping it's as simple as clearing the codes!
Jon
Re: 2.4 t-smec rev cutout - launch control?
Sweet!
Try again with those pics. Would love to see whst he has done with it! I don't know that he remembers me, but I've never forgotten that Rampage!
Re: 2.4 t-smec rev cutout - launch control?
I guess on my 2.4 swap with the SMEC, I just used a 2.5 cal and had it dyno tuned instead to get the fuel and spark correct.
Re: 2.4 t-smec rev cutout - launch control?
Hey man! I'm the guy in the Pathfinder the other day that followed you all through Vernon like a crazy stalker! Then started yelling and cheering when I pulled up along side you at the red light! Haha !!! I'd live to talk to you and come by and check that BEAST out! If you'd like to call or text me that'd be great! 9134051 with the regulator CT area code (don't wanna put the full phone number on here ;) ) but yea man, I created two posts on the rampage Facebook group trying to track you down!! Hahaha I'm a starion/conquest enthusiast myself but your car is freaking sweet. Thanks man!!
Graham W
Re: 2.4 t-smec rev cutout - launch control?
Well, I went down to Merrill's shop at lunch, cleared the codes and the motor ran way better! Holy cow does that tiny stock turbo spool quickly! Have it set for 14 psi of boost to start with and it hits full boost almost instantly!
We're using a 3 bar map with +40's to start with. I'm not sure how much boost those will support on 2.4 16 valve motor, but I'm guessing that tiny stock turbo can't be very efficient much past 16-18psi so I'm thinking the +40's should be good enough until we upgrade to the bigger turbo setup. Any input would be appreciated.
The only thing I did to Rob's 2.4 t-smec cal was make sure it's scaled for 3 bar map and +40's. It seems to idle fine and has plenty of fuel under boost, but on decel the engine pops and backfires and the wideband goes off the chart lean. So I need to work on that, but was wondering if anyone else has experienced that same condition using the t-smec cals?
FYI - I responded to your private message earlier this morning Graham.
Jon
Re: 2.4 t-smec rev cutout - launch control?
Quote:
Originally Posted by
1986GLH
I guess on my 2.4 swap with the SMEC, I just used a 2.5 cal and had it dyno tuned instead to get the fuel and spark correct.
We originally were going to go that route (got it fired up with a 2.5 t-smec cal), but then I found the 2.4 base cal for the t-smec in Rob's collection and we decided to use that instead. Are you happy with your tune? Would you be willing to share so that I can do a comparison to the 2.4 cal we're using?
Jon
Re: 2.4 t-smec rev cutout - launch control?
It's probably tuned to pull fuel on decel. Lots of people like the crackle, and it saves a little fuel.
Re: 2.4 t-smec rev cutout - launch control?
I just compared the 2.4 base cal in the t-smec zip file to the 2.2 and 2.5 t-smec base cals, and some of the tables seem to have different data points in them so something seems off. I'll play around with it more later this week, but may end up trying the suggestion above and using the 2.5 t-smec to start with and adjust as necessary.
Re: 2.4 t-smec rev cutout - launch control?
Quote:
Originally Posted by
jonnyb
We originally were going to go that route (got it fired up with a 2.5 t-smec cal), but then I found the 2.4 base cal for the t-smec in Rob's collection and we decided to use that instead. Are you happy with your tune? Would you be willing to share so that I can do a comparison to the 2.4 cal we're using?
Jon
.
I'm fairly happy with my tune. It isn't 100% yet, but does drive decent and makes good power. It did 378whp to the wheels. I'd worry about sharing my tune because of the amount of timing it is running. I don't want it to blow up anyone's engine.
Quote:
Originally Posted by
jonnyb
I just compared the 2.4 base cal in the t-smec zip file to the 2.2 and 2.5 t-smec base cals, and some of the tables seem to have different data points in them so something seems off. I'll play around with it more later this week, but may end up trying the suggestion above and using the 2.5 t-smec to start with and adjust as necessary.
Different data points? I ended up changing a lot of the tune so didn't really matter what I started with. I just used a 2.5 cal because it seemed to start well with it and didn't want to change the starting fuel or timing.
