350 with 30lb injectors

[brianko]

I was actually talking about the ability to hold a steady RPM and vary engine load, very essential for accurate partial throttle tuning, very difficult to achieve on the street. At best, street tuning requires very coarse-grained interpolation.

[EagleMark]

It's not as hard as you think. Just takes more time, hills are your friend, lower tire pressure, some guys even pull a trailer, ride the brakes... getting some key data points and smoothing the tables.

Dynos are just to easy!

[Six_Shooter]

I was actually talking about the ability to hold a steady RPM and vary engine load, very essential for accurate partial throttle tuning, very difficult to achieve on the street. At best, street tuning requires very coarse-grained interpolation.

You sound like someone with little to no tuning experience who has only read internet lore.

I get part throttle tuning nailed pretty quickly, without a dyno.

Don't let internet myths confuse you, street tuning is one of the best ways to tune a street vehicle, by someone that knows what they are doing, which just takes experience.

As mark said there are ways to hold a steady RPM and change load, but it's not as necessary as you seem to believe to tune this way.

[brianko]

You sound like someone with little to no tuning experience who has only read internet lore.

Actually, no. I've been tuning OBD2 stuff for years. Thought it was time to learn about the OBD1 stuff. But I'm not here to get into a pissing contest with you. You way works, my way works. I think we can leave it at that.

[brianko]

Found some data on the 30# Accel injectors, not much to work from. Extrapolating the few values that are available results in these numbers:

25.6 0.00
24.0 0.00
22.4 0.00
20.8 0.00
19.2 0.00
17.6 0.00
16.0 0.00
14.4 0.00
12.8 0.00
11.2 0.00
9.6 732.43
8.0 1495.38
6.4 2807.66
4.8 4364.07
3.2 5981.53
1.6 732.43
0.0 701.91

(The last two values are a wag based upon the stock table...and yes, Accel says 0ms for anything above 11.2!)

At any rate, this table along with an 80% scaling of the BPW tables results in an idle of 14.7AFR and immediate startup.

[Dewayne_S]

But I'm not here to get into a pissing contest with you.

Thank God for this. Pissing contests and smart ass remarks like "Do a search before you start a new thread" is a lot of why I stopped going to another well known and very popular site.

Personally I have never been around a Dyno, I would think it would be easier with such a controlled environment. All my tuning has been done on the street and track and I must say I have had really good luck getting it done.

[EagleMark]

This may be the first misunderstanding between people here? We just don't do pissing contests here! So let's just let it go. Some times things just come out a little to blunt typing on the net, but never meant to stir the pot. I won't allow it!

Read any tuning book and you will see dyno tune is only way... well we know that is wrong but the people writing the books or ones with dynos have never had to work without a dyno.

Back to fun!

[1project2many]

Thanks for posting those Accell numbers. Can you quote a source?

I was actually talking about the ability to hold a steady RPM and vary engine load, very essential for accurate partial throttle tuning, very difficult to achieve on the street. At best, street tuning requires very coarse-grained interpolation.

I imagine your local geography plays a major part in this thinking. In Texas the roads are probably as flat as the horizon and just as long, too. But in other areas there's enough hilly terrain to do this type of tuning quite thoroughly so the load dyno is more of a luxury than a necessity.

And of course there's always the old "Semi-trailer axle mounted in concrete with an air pressure regulator on the brakes" trick when the hills just won't work.


BTW, Mark, you really should think about building one. Here's another success story:
http://jalopnik.com/5807502/how-to-b...2000/gallery/1

[EagleMark]

If I had land I'd have built something long ago!

[brianko]

Hey, it's a Dynojet! :)

Accel numbers came from this forum post:

http://www.chevytalk.org/fusionbb/sh...hp?tid/247139/

The interpolation was my own...

[1project2many]

If I had land I'd have built something long ago!

Land??? You mean so you can recover parts without disturbing the neighbors? I'll offer some space out here. I'm on the side of a hill... the front yard looks perfect for that setup.

Accel numbers came from this forum post:

http://www.chevytalk.org/fusionbb/sh...hp?tid/247139/

You know, way back in the beginning of this thread I found that discussion and read through it at least twice. Read it again tonight, then again just now thinking "This guy's imagining things." Can't believe I missed this:

Called Accel EFI tech support and spoke to Dave. He said he gets the request for Off Time Data sheets fairly often for their Accel Injectors. However, they sheets do not exist. I convinced him to give me the voltage vs Msec from their DFI program. Here is what I got:

at 11.80 volts or higher = 0 MSEC
at 9.5 = .74
at 8.3 = 1.20
at 7.1 = 2.0

Glad I didn't decide to be a professional rattlesnake hunter. Sheesh...

[ZEDRATED]

Hi all, damn email wouldn't send me notifications when you guys replied. I did a google search and I saw my thread come up and realized its very alive again after 2 months lol. Sound like a lot of hostility here lol.
Six shooter, I wanted to bring my car to you to tune but you never emailed me back. I know have it put away for the winter and I won't be playing around with it until the spring. The computer is still hanging on my passenger floor for 3 months now lol.
1project2many, are those the right voltage correction tables? Would you be interested in tuning my car in the spring?
My cousin referred me to a dyno tuning shop out here in oakvile named Neetronics, a fellow named Andy said he has a guy to dyno tune my car with a wideband o2 sensor and I was going to bring it there in the spring. I do appreciate all I have learned here off you guys.
Thanks.

[1project2many]

1project2many, are those the right voltage correction tables? Would you be interested in tuning my car in the spring?

I don't know. They are the only values we have with nothing to compare to.

Sorry, but I'm not able to take on the job of tuning your car.

[ZEDRATED]

Ok. No problem. I will see how it goes at the tuning shop near me in the spring. He said anywhere from 2-4 hours so if I can get it running good for under $500, I'll be very happy. I'll post back here in the spring after I go to him.
Thanks.

[EagleMark]

Inertia dynos, sure. But load dynos have their place. I'd like to see how you maintain constant RPM and change engine load on the street...

Easy, learn to look at what's not in the numbers that's being spit out of the ALDL. ;)

What I mean by that is, the numbers are not the "end all, be all" to tune from. There's a lot more to tuning than just going off some numbers on a display. ;)

You can get good data points, filter some items and finish building the table. Wideband will confirm final tune. Go to dyno and be within 5%.