Just as a follow up:

The car went to the track Sat., for it's first series of shake down runs. First pass was a 14.4, and within 5 passes was down to 11.6s, leaving light, and shutting off at the 1,000' mark.

Yep, knowing what each change was suppposed to do, and then going one step at time, does work.

Now with the data logs from 3 meaningful passes, the first two passes were just to make sure the car was stable, now we can start noting trends, and again run things on the bench to best taylor the chip to what the car best likes. ie cut and paste different areas of the various chips that had certain best items.

And that was with Low boost, the tiny old slicks, race gas, thru the muffler. For the classes this car will run in there are tire size rules, so there in the tiny set, and the gooduns.

So starting from scratch, tune wise, 20-25 mins of legal street driving with the WB to verify things were as calculated on the bench, and then 5 passes to get to the mid 11s. Granted several hours of work was spent on the bench working things out, but IMO it seems to have saved several hours of wear and tear on the car getting things close.

And the shut down at the 1,000' was an attempt to stay out of the 11s. Since the cage wasn't in yet. But, that's this winters project anyway.

And that was with a little over 80% DC, so we have plenty of fuel for when we crank the boost up. 72 PPH injectors.

So it'll probably take like another 5 passes and we'll have the car base lined, and running well. About the biggest chore will be working out the weather corrections, and that's just a matter of getting the car out, under different conditions and seeing what it likes.

Oh, and this cal works from off idle to WOT hitch free. 17-19-23-25 PSI there's enough resolution to run there. BTW, it's a MAF system, that reads to 750 gm/sec..
The code work in this setup avoids the pit falls, that I've pointed out in the stock MAF systems, used in the 3rd gens..
I never said, I don't like MAFs,
All I ever did was point out the weaknesses in the stock setup..
LOL, maybe this lead someone to think about, and figure out what really needs done to get the MAF systems correct.

 

Daaaaaaamn, talk about the power of proper prediction!

 

Hehe...

I see the little guys have been busy..

nice...

 

Would you post some of data of that last run? What mph, etc.
Was that with the c3 or the p4 ecm?

 

I'm not into playing the ET/MPH, bench racing game. When we do a full pass, that will be what we do.

As far the DIY PROM stuff goes, that's with the ol 1227148 C3 ecm. By spring, we'll have a P4 option for it. Actually I could do it now. Just flip the bit in the 148, and rerun the data, to get it in batch fire version, and then use the ecm bench to generate the new bin for the other ecm. That avoids all the muss and fuss of having to do an entire recal.. Thou it probably would be 10-15 mins of test driving to verify all is well. Just another use for having an ecm bench.

 

Grumperson,
Nice work.
IIRC, you're running the turbo motor with a 7th injector and no intercooling. If this is so, why not fit an IC and drop the charge temps?

And another, "why have you done it this way?" question- why the C3 instead of a P4 with $58 code?

And a third- why go to all that trouble with a big MAF (and translator?) adaption?

John

 

I read this several times.....your using RACE GAS? After all the crap you guys said about that. Anyways.

Just for comparison purposes.....can you scan in your slips so I can see them for interval ETs. If you don't have a scanner, pictures will be fine, as we know you have a digicamera from your other posts.

BTW: Regardless of our past run-ins or the race gas....good job at the track and the results.

 

This is my neighbors car. It uses a CAS V-1 Intercooler, ie huge front mount.

He's just gotten the car up and running and in an effort to not change too many things at once, started off with the 148 ecm.
There are several things we'll be testing.

Why not?.
We have plenty of ideas to play with, and this is just one of them. The 749 set up is plug and play, and I also have another ecm on the way that we're going to work with. Just a work in progress thing.

 

Small motor, big hp- cool

Third Gen content- this motor is in some TA's isn't it?

Is the "why not" comment about your non-intercooled setup?

Basic reason for my curiosity is that I've bought an Eaton M112 S/C for my 5.0L V8, and that the IC options are limited. I may start with an upstream injector under boost, sort of like you've used. Do you plan to install an IC at some stage?

John

 

89 Turbo Trans-Am is basically the same as the 87 GN powertrain.

The why not is about experimenting. Different ecms, different mods, etc., not unlike some I keep my options open.

Nope, I'm not planning on adding an I/C. Basically an I/C is a thermal flywheel up until you get into the really large sizes, where they can exchange enough BTU's to be effective. Once you get to 2x2' then they can get really effective. For the weight and bulk I think I can do better without it. Just using the existing 7th injector has me within 10d or so of the oem intercooler. 8th injector is undergoing testing and, revisions, hopefully that'll take me to better then most I/Cs.

 

I'm clueless when it comes to GN motors (and turbos in general), so take it easy on me...

how far upstream is the 7th injector?

 

On the GN/89TTA Throttle body there is a bolt on vacuum block. The 7th injector replaces that piece, holds the injector, and adds a discharge port for the injector right behind the butterfly.

 

Still puzzled...

Are the 7th and 8th injectors are injecting gas or water?

 

Gas....


BW

 

Are your sure? My understanding was that it was hydrazine. Just don't know anymore. . .

RBob.

 

The 7th is gas...

unless something's changed..

8th... May or may not be gas.. not sure.


Your right.. it's hard too keep up..

BW

 

The 7th and 8th injectors are gas.

Other then that, and no Blue Bottles, Doc ain't even talking.

 

Grumpy, how long are you going to be having those injectors fire? Also, how low can you pulse those big P&H injectors? Might explain your high idle, yes no?
Is your cam stock or are you running that POS cast roller? Sorry for so many questions, I'm just trying to figure out the whole extra injector thing. I know Cornell has been doing it for a while on there turbo formula car. They run hot air with the extra injector just like you. Injecting gas is a good idea but water might be better for pre turbo, just a thought. I still think you need a heat exchanger . I know Cornell runs hot air because of weight and packaging, also TR is worth twice as much as HP in our tight autocrossing events.

 

High Idle?, Who?.
I can take em down to lean surge, ie .7 msec.
Why the POS comment starting to sound like others that I'm starting to just ignore.

Have you inspected a turbo that's had serious amounts of water pre-turbo?. Stop by Columbus Diesel and ask to see one of their compressor examples of what big water can do. Water means carring extra weight, and the possibility of running out, for limited cooling the extra injector works.

It's easy to play follow the leader.
Hence I take different paths.

 

Give him a break Bruce. He was insulting the camshaft, not your intelligence.

John

 

There still is no need for that language.
According to the charter this is supposed to be a family oriented site, around here, that means no name calling. Also, I can set the standard for the people I want to communicate with. After several decades of working in a shop, I can use the jargon, but I reserve that causualness for when in person amongst adults.

Not to mention that universal statements can sometimes be wrong.

BTW, I never take anything anyone says over the net personally. Thou some like to read that into my responses.

 

I thought your idle was around 1000, just an observation, car might have still been cold. Most of the time I couldn't tell what was going on because things were coming at me so fast and the speedo only went up to 85.
I wasn't talking big water, I know what that can do, it's a shame. I was just talking about a high mist to keep the turbo cool. I do still think water injection with some methanol would be perfect for your hot air ride. The methanol will keep it from freezing in winter if you ever do take it out on a cold day. The weight I see as a problem but it's been measured that the benifits of water injection pre-turbo can have almost nill effect on your air delivery other than to lower temps and create a more dense mix = more hp.
I resent the comment about follow the leader if it was towards me and turbo talk. I like difference, I don't like seeing the same thing over and over again. I just like to see research, as do you.
Oh, and that cast roller cam, I thought we were in aggrement that it was a POS.

 

So how does this provide aftercooling? Wouldn't it just make you run rich?

Ahh... I just found your article on GNTTYPE.org...

so the 7th injector is adding gasoline as a liquid, and the 'cooling' is coming from the phase change of liquid->gas?

 

Yes, the "latent heat of vaporisation" or evaporation is absorbing some of the heat, and providing a denser charge, with less chance of detonation.

And if you do what Grumpy has recommended several times, set this up on a flow bench, you might even be able to check that under boost conditions you get an injector pulse width that will allow you to hit your target AFR. I'd be interested to hear what has to be done to the code to make this work well though.

John

 

Bruce,

You misinterpreted him entirely wrong. Can't you just say "woops - sorry" and move on? He obviously was insulting the STOCK camshaft. No need to be so defensive .... especially against someone (JPrevost) who has always been on your side on most of the discussions here. And - as far as the language is concerned - I've seen a few times in the past couple of months where you have done the same (Using the term 'BS', etc.). It gets you nowhere by attacking those who have stuck by you through the thick of things.

Tim

 

It's easy to play follow the leader.
Hence I take different paths.

OK, tell me how you see this as being addressed to you?.
I said, I, I take different paths. There is nothing for you to resent, I was just stating what, I, do. And there is nothing wrong, with following the crowd. Some folks do that. And that doesn't infer that you do. If I didn't think highly of you, I sure wouldn't invite you into my house.

Which cast Roller?.
You made a blanket statement, about ALL of them. The econo cam rollers were a bad deal. But, that's different from saying all of them.

Being close to Columbus, I thought it would be worth your while to hit that place to see what WI can do. They happen to be good folks, and work with seriously big HP applics.. I was tossing a tidbit.

The LEDs for the tach do indicate high. The 1K bar illuminates at less then 800.

And if I thought we needed to seriously discuss things, I'd have taken it off list. Comments in passing ain't worth getting in a twist over, IMO..

 

Replying isn't just about being defensive.
It's about just expressing one's point of view, ie sometimes called dialog.
This isn't about taking sides, it's a discussion.

BTW, the stock cam wasn't a roller.
And the story about cast rollers for the GNs isn't hardly a PROM issue, so I'm just not going there.

And the comment about language was just in passing, ie kind of an announcement. If I thought it was important or an issue, I would have written him off list.

 

Gotta love it!
Another thirdgen in the 11's.
Good job.

 

I believe it's a GN (Bruce's neighbor).

 

Ohh well , good job regardless. I always was a big fan of the Turbo 6.

 

I've always wondered this.

I've been told WOT Fueling is based on BLMs. (Percentages added onto the base blms that is)

While you have to drive the car around a bit to get the computer to learn the new BLMS of the new chip.

Thus I thought Swapping chips at the track would provide little accuracy since the computer hasn't learned it yet.



How does that work?

 

It depends on the code your using, there are several different fueling strategies. Some lock the BLs at 128, and some allow for rich corrections.

For most everything I do, I use open loop. And I use a WB, alot.

If your tuning at a drag strip then you should have already done the low speed stuff so that reguard it should be a constant.

 

$6E code that locks the blms at 128.

So you're saying that if all I do is take out my chip, change PE.... then the computer doesn't have to relearn the parameters, just adds the higher PE?

Same would apply for spark too correct? If I set my WOT approx spark at say 30-32-34-36-38 in 5 different chips with everything else the same, it wont have to relearn to be accurate, just changes the timing?


How come one day my blms are at 122-128.... add more pe to that chip, and then the next day my blms are 114-118? Makes no sense to me.

 

Yes.
Spark has no learning function.
Small weather changes can effect BLs. You almost need an ecm bench to really isolate small changes to see what they actually do.