B&G Flash

[Boilermaker]

Haven't seen too many performance related threads, but in case anybody is interested here's a copy of what i posted over in the performance section at LOST.

Ok, so i'm ready to take the plunge with the B&G flash. I know KYLiberty has covered this a lot of this in previous threads, but here's an average guy's perspective.

While i guess I could use my current PCM, i wanted to pick up a second one so that i a)didn't lose my jeep for a little while and b)could throw the factory programmed PCM back in if the KJ went in for service. I've read others bought new PCMs, but i went the used PCM from a junkyard route because i found one for a fraction of the price of new. The thread i started a while back has more details on that.

Took the PCM to the dealership for programming. They swapped the second one in, programmed it and charged me for 1 hour worth of labor. The junkyard PCM is currently in my KJ and its working the same as the original.

Called B&G this morning with some questions. I have the Mopar dual outlet exhaust and a K&N FIPK, but plan on doing more mods. They confirmed that i don't need updates as i do more modifications...which fits right in with KYLiberty's advice to do the flash first. While i want better performance, i'm also concerned with gas mileage. The KJ is my daily driver (often over 100 miles/day) and i didn't want to sacrifice too much gas mileage for power. B&G claims that a flash should actually increase fuel mileage some...good news, hopefully something i'll be able to verify down the road. Along the same lines, i asked them about the black soot some of us see on the tips of our exhaust. They told me they lean the fuel mixture out some, which should help with that.

They asked me to give them a call first before i send in the PCM...which i will be doing this afternoon or tomorrow. Basic stuff, return address, payment info, VIN number, etc. Ship to them on my dime, they cover the return shipping. They told me turn around time is two days from when they receive it, so hopefully i'll get it back by the end of next week for a weekend install.

If there is any interest, i'll post the post-install results.

 

[JeepJeepster]

Im glad that someone else is doing this. Ive been wanting to do this for some time but I just dont have the money at this time. Please keep us up-to-date.

Also, if you dont care, ask if the program changes anything with the ******. Will it change the shift points so that it doesnt shift into 4th to early like it does now?

Where did you get the new computer? I found one on ebay for $175 that has a 1 year warranty.. Found them new for $400..

 

[Boilermaker]

I'm going to try to get it out today to make sure i get it back by late next week. I can ask about shift points and torque management when i call them this afternoon.

I understand where you are coming from, i thought about it for a while before going thru with it. It is an expensive mod, even with getting the PCM relatively cheap the final cost is going to be around $600. I know KYLiberty swears by it, but he also takes his KJ to the dragstrip and has a heavily modified powertrain. I guess i'll be the test subject for the more or less average guy.

 

[Boilermaker]

Just got off the phone with B&G...they change the shift points so that shifts are made at higher rpms, so it should get into 4th a little later. I should have some first hand experience in about 10 days. In the mean time, i'm going to start taking some base line number for comparison.

 

[JeepJeepster]

Taking base numbers is a great idea. I would find a nice flat piece of road to see about what speed the ****** currently shifts. This makes me want to do this 800times more!

 

[Dave]

You guys need a Hemi............er wait, you'll have an SRT6-KJ. I am real interested in this thread. hehe

Dave

 

[JeepJeepster]

You guys need a Hemi............er wait, you'll have an SRT6-KJ. I am real interested in this thread. hehe

Dave

Guess Ill be ordering some SRT-6 badges! I like where this is going..

Ive got enough money saved up to ALMOST get this.. If I detail a few cars, Ill have-er done! That is if boilermaker gives it the thumbs-up!

Got a shift kit coming for the 42rle too!

 

[Boilermaker]

Got a shift kit coming for the 42rle too!

I've got the shift kit....just haven't put it in because i'm going to have to have somebody else install it and its money that i no longer have. I wasn't optimistic about them when i heard its was more of a corrective kit. After the flash i may want to change some of the shifting characteristics...or even do something to balance out some of the extra wear the lack of torque management might inflict on the ******.

Guess Ill be ordering some SRT-6 badges! I like where this is going

I like that idea....

I've had the KJ back for a couple of weeks, so hopefully the swapped PCM has adjusted to my driving habits enough for testing. I'm keeping track of:

• Mileage and what % of it is highway/rural/city (won't be much city tho)
• Its not hard to find a long empty stretches of roads that have 65mph limits, so i'm hoping to do a few unofficial 0-60 runs. Quarter mile is probably not going to happen tho.
• I'll keep track of my shift point this weekend while i have a passenger in the car to write stuff down.
• I have one of those scanguage IIs...i'll have to look and see if there is anything useful info i can get from that.
• Sometime later in the summer i'm planning two more mods. The first is the fastman TB. The second is that i'm going to do a variation on the gutter drain mod to get more air to the intake. More numbers after each of those mods.

Short of a dyno, any other suggestions?

 

[Ry' N Jen]

Good day,

So far I like what I'm reading!
More power under the hood sounds good to me.
I am curious as to what RPM the additional HP and torque start and end.
If it's in the upper RPM it would really fit me needs. I want extra torque on the bottom end for steep trails and off road mountain passes. but if the torque curve was even across the RPM band, that would also be sweet!

Anyway, I'll keep reading, as I to am interested in this topic.


Cheers
Ryan

I remember my dads Ford E350 with a heavy duty trailer (15000 lbs.) package and a 460 c.i.d. and 350hp at the rear wheels, oh, and some
600+ foot pounds of torque! Thats power!

 

[Boilermaker]

Received my flashed PCM yesterday. Swapping PCMs involves only three screws and 4 connectors and takes all of about 5 minutes with the right tools. Some initial, seat of the pants impressions after about 80 miles of driving:

Hammering the pedal nearly to the floor, the RPMs build up much faster and one result is that my KJ seems quicker off the line. In 3rd and 4th gears the RPMs increase just as quickly, but there doesn't seem to be as much effect. If i put it to the floor at 55mph to make a quick pass, i don't really feel a difference. Because the RPMs build so fast, the shifts are happening at higher RPMs, maybe 1k later.

Surprisingly the fuel mileage is close to the same (21.9 the previous 1k miles, 21.0 yesterday). Considering that almost every chance i had to accelerate i did it at full throttle, that's not bad.

One strange thing i noticed, when i put the key in the accessory position, my CEL will come on, then blink. With the old PCM it would just stay on, just like the battery and other idiot lights do. Doesn't result in any codes tho.

Sometime this weekend or next i'm hoping to do some hand timed 0-60s with each PCM. I'm also going to watch the fuel mileage and my tailpipes to see if/how long it takes the carbon to build up on them.

 

[JeepJeepster]

Is it worth the $$?

Does it keep the ****** from up shifting to early? Thats really and truly the only thing I want it to do is change the shift points. I cannot stand how it will shift into 4th gear when you are accelerating. Then it downshifts since it upshifted to early..

Im calling APS to order the shift kit right now..

 

[Boilermaker]

Jeepster, i sent you a pm about the first part....

Is it worth the $$?

Its only been one day...but my first impression is that there are other performance mods i would do first. A less restrictive exhaust system and the rain gutter mod (because costs almost nothing) seem to be better bang for the buck options. That may change tho when i figure out some less subjective tests.