Topic: Any insight on dynatech long tubes?

[Main One]

It took me 2 weekends to do it, primarily because I wasn't using the proper socket and rounded off one of the bolt heads where one of the manifolds tied into the rest of the downstream exhaust plumbing.  With the JBAs, I didn't have to mess with the steering shaft.

While they were supposedly ceramic coated, they are showing some rust.  However, I've got something like 150,000 miles on them.   

I'd say they gave more of an improvement than an aftermarket cold air intake.  Tuning afterwards does help.  They would affect Volumetric Efficiency and hence you would want to tune the VE table.

My AV isn't what I would call sluggish.  Tuning helps with that, by setting shift points by as much as anything else in mine and a lot of other cases I would say.

[USMC0311]

It took me 2 weekends to do it, primarily because I wasn't using the proper socket and rounded off one of the bolt heads where one of the manifolds tied into the rest of the downstream exhaust plumbing.  With the JBAs, I didn't have to mess with the steering shaft.

While they were supposedly ceramic coated, they are showing some rust.  However, I've got something like 150,000 miles on them.   

I'd say they gave more of an improvement than an aftermarket cold air intake.  Tuning afterwards does help.  They would affect Volumetric Efficiency and hence you would want to tune the VE table.

My AV isn't what I would call sluggish.  Tuning helps with that, by setting shift points by as much as anything else in mine and a lot of other cases I would say.

Right on! I appriciate the info. I just got some good news from my military education benefits and looks like I will have some extra $ so I am gonna grab a set of JBA's I suppose. I figure after that and a tune she should drive more to my liking. You used HPtuners correct? I was thinking about sending in my PCM to Nelson and have them do a custom tune for me, just seems like I will get more out of that than out of a predator or something of that nature. Once again thanks a bunch for your insight, I really do appriciate it!

[Main One]

Right on! I appriciate the info. I just got some good news from my military education benefits and looks like I will have some extra $ so I am gonna grab a set of JBA's I suppose. I figure after that and a tune she should drive more to my liking. You used HPtuners correct? I was thinking about sending in my PCM to Nelson and have them do a custom tune for me, just seems like I will get more out of that than out of a predator or something of that nature. Once again thanks a bunch for your insight, I really do appriciate it!

Yes, I use HPTuners.  I can let you see how it works Sunday at Bratfest.  Compared to one of the handhelds, you can definitely get more out of a custom tune, whether you do it yourself or have one of the pros like Nelson do it for you.  (I'm running my efans using a Nelson wiring harness.)  This is especially true as you put more performance parts on/into your engine, tranny, etc.

I've learned so much about how my engine, and engines in general, work by using HPTuners.  I figure I could learn even more, and even mentioned to the wife last night that I was interested in taking a tuning class called EFI 101:

http://www.efi101.com/efi101.html

They've got a class coming up on 10-11 October in the Chicago area that I am seriously thinking of signing up for very soon.  ($50 off (about 10%) if you sign up a month or more in advance.)  I figure it is sort like getting any other work done on your car - understanding what needs to be done and roughly at least how it gets done makes you a better consumer if you have Nelson or someone else do the programming for you.

Some people (like BlueDevil  ) are a bit afraid to jump in and play with HPTuners, but it really isn't rocket science.    

[MyBigToy]

Take the class, then you can teach all of us!

I hope we can spend at least a few minutes reviewing the basics of VE and MAF tuning. I've been reluctant to do this with only reading instructions @ HPT and PT.net. I want to make sure I know that I'm setting the MAF to "fail", etc. properly before I get started.

I've worked on most of the other parameters and spent quite a bit of time nosing around in the tables. Part of my problem is that I don't drive my truck enough to fill in the tables after making a change. It will be good to get some pointers from someone who has spent enough time with HPT to know their way around and can explain the info.

[Main One]

Take the class, then you can teach all of us!

I hope we can spend at least a few minutes reviewing the basics of VE and MAF tuning. I've been reluctant to do this with only reading instructions @ HPT and PT.net. I want to make sure I know that I'm setting the MAF to "fail", etc. properly before I get started.

I've worked on most of the other parameters and spent quite a bit of time nosing around in the tables. Part of my problem is that I don't drive my truck enough to fill in the tables after making a change. It will be good to get some pointers from someone who has spent enough time with HPT to know their way around and can explain the info.

LOL, I'm on my 162nd tune, just since installing my cam 2 years ago.  I've probably put around 300 tunes into the thing.  I've probably only played with about 1/4 of the parameters, maybe a whole lot less than 1/4.

Last winter, I decided to try to "fix" the problem that I had - my LTFTs were not stable over temperature.  I suspected that with the close proximity of my MAF in my custom intake to the throttle body and cone air filter, the MAF's sensors needed to be located more towards the perimeter rather than the center.  (It seemed in the colder, hence denser, environment, the MAF was not detecting low airflows very well.)

I modded my truck's orignal stock MAF to move the sensors, and did indeed conclude that there was a positive effect by moving the sensors, but not enough to fix my problem.  I decided then to try to fix the problem via software, specifically the IAT/ECT bias vs airflow table, which basically identifies how much IAT or ECT affects the calculated airflows.  (At low airflows, ECT comes into play more than at higher airflows.)  After 6 months or so now of collecting cold and warm data before doing retuning, I am now hopefully getting very close to having the problem fixed.  The proof of the pudding will come when I can get some really cold, sub-zero data this winter.  

For the last 6 months, between retunes, I've tried to collect data from the coldest mornings to the warmest afternoons in about a week's timespan, which here in the midwest are usually 20-30 degrees apart, although I have been "lucky" enough in the spring to get a 50 degree spread.

Anyway, will show details on Sunday.

[bluedevil]

Other things for ya to drool on

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