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RUTHLESS
08-12-2007, 01:40 PM
Hey guys! The car has been running great since I fixed the spark plug problem and found a few more HP. lol

Yesterday while running a street bike I went WOT and ran the old girl to her limits and found a problem. Beside the back end wanting to spin on small bumps!! lol I think the problem it has to do with the MAF being close to maxing out as we saw on the dyno. Here is the story.
I was just playing with the guy on the bike until he took off so I down shifter to third gear and went WOT. The car started to pull then just stopped! The boost was holding fine but the RPMs were not going up at all. It didn’t buck or make any odd noises so I backed off the throttle and pushed it down again and she started pulling hard. I thought it was an odd at first and didn’t think much of it. As the bike and I came to a bend we both slowed down. (Hey we were just playing and didn’t want to kill each other.) At the next straight away it was on again! I was in third gear this time and in my power range so I smashed the gas. The cobra was pulling hard until about 5k rpm then I hit that darn hesitation spot again and stopped pulling, the bike was pulling away, so I eased off the gas just a little and smashed it again and she came to life and put me in the trunk!
So what is going on here? From what I read it seems like fuel cut caused by the MAF maxing out. AM I on the right track? I don’t plan to run the car hard again until I get this fixed. For the people that don’t know...The fuel system is stock and so is the MAF. I am running a 2.93 upper on a ported blower with mid length headers.

Viper_ed
08-12-2007, 01:47 PM
If you're at 472 rwhp with just the stock MAF and you don't have a MAFia, I would say that's your problem. From what I remember, the 460 rwhp mark is where 95% of the cars already have the MAF pegged at 5.0v.

Blackcobraconv
08-12-2007, 01:53 PM
I know someone with a brand new Mafia for sale if you need one.

RUTHLESS
08-12-2007, 02:28 PM
Viper_ed,
That was my thinking too. On question...If I get the MAFia would I need a retune? My guess is yes because my understanding is that the MAFia moves the MAF scaling down.

u1arunit
08-12-2007, 04:06 PM
Viper_ed,
That was my thinking too. On question...If I get the MAFia would I need a retune? My guess is yes because my understanding is that the MAFia moves the MAF scaling down.

Yep you would need a re-scaled MAF curve tune.

Viper_ed
08-13-2007, 12:15 AM
Mark is correct on the retune!

RUTHLESS
08-13-2007, 10:02 AM
Thanks for the help guys! It sounds like I was on the right track and need to make a small list of toys to put on the car to take advantage of a retune. MAFia, BAP, CAI and maybe a 2.7x pulley. Come on 500rwhp!! If not a little juice will help. lol

BoneCrusher
08-13-2007, 10:09 AM
Sounds like you are on the right track. Many, many terminators have had these problems and it is fixable. You may want to contact Wolfpack Speed if you need any help with this one.

Who tuned your car?

Viper_ed
08-13-2007, 10:10 AM
I'd add a lower pulley instead of going with the 2.7x upper. You will get less belt slip and you will also get more tq with the lower. Just remember to get a bigger alternator pulley if you go the lower pulley route so you don't overspin it.

RUTHLESS
08-13-2007, 10:30 AM
Who tuned your car? I am not sure because the car was purchased this way. This is the last time I buy a car like this. I did have it at the Big Shot dyno day with the group and we saw that the MAF was going to be a problem.

Viper_ed,
I will take a look at the lowers and see how big of a pain it will be.

Viper_ed
08-13-2007, 10:36 AM
Viper_ed,
I will take a look at the lowers and see how big of a pain it will be.

Just a FYI, the lower is actuall easier to change than the upper since you don't need the special pulley puller for the Eaton.

BoneCrusher
08-13-2007, 11:39 AM
I am not sure because the car was purchased this way. This is the last time I buy a car like this. I did have it at the Big Shot dyno day with the group and we saw that the MAF was going to be a problem.


Man I hear you on that one.

Mike at Wolfpack deals exclusively with Jon Lund who IMO is one of the top 3 Terminator tuners in the country, he's been doing it since the beginning and has owned these cars personally. I am going to have my car retuned by him through Mike soon.:awsome:

Viper_ed
08-13-2007, 11:43 AM
I am going to have my car retuned by him through Mike soon.:awsome:

I'm not saying anything against Jon Lund. He's an excellent tuner! But why the hell are you getting your car retuned Crusher???? :dunno:

BoneCrusher
08-13-2007, 01:09 PM
I'm not saying anything against Jon Lund. He's an excellent tuner! But why the hell are you getting your car retuned Crusher???? :dunno:

Ken at MD tuned it almost 3 years ago and it's a good tune but I have always had little issues that I just kinda lived with nothing big though. It's just been three years since my cars really been looked at and I just want to make sure everythings still where it should be.

I'm going to have Mike throw in some new plugs, do the PPRV and datalog my car and have Jon clean up my tune using the info from Mike's street datalogging.