Finally Intercooled

[AleroB888]

Update 3 (Final chapter?? )

For the first test and tune this year, I had two main objectives:
1) Run without the alcohol injection and Maf Translator, but still duplicate or beat last year's best ET.
2) Test a new muffler system (required for the class I run in).

These would be the first runs with the new Lucas Injectors, IFR set at 38. LTFT's were staying consistently in the negatives, but not too bad. Target afr tables left at stock. A pressure switch activates the IC pump during boost.
Last year I used the Maf Translator set at +10 deg. WOT and ran a best of 14.028. With the Maf Translator removed, HP tuners is used to add timing in the IAT spark table at the lower temps., and subtract it at the higher temps. ....
So for Cylinder Airmass at or above 0.68 g/cyl,
+10 deg. timing @ 50 deg F,
+10 deg. @ 68 deg. F
no change at 86 and 104 deg. F.,
minus 4 deg. > 122 deg. F.
High Octane Spark 21 deg.@ WOT, Low Oct. Spark 18 deg. @ WOT

Test and Tune, April 14, '07 (Bandimere Speedway) (ambient temp 60-70 deg.)

1) 14.184 @ 96.75, 2.126 60 ft.
2) 14.125 @ 98.05, 2.200 60 ft.
3) 14.172 @ 95.86, 2.126 60 ft.
Notes: with Magnaflow muffler # 14828 installed, IC water temp 40-50 deg., IAT in IM 72 deg at start, ECT 185-195 deg.

4) 14.057 @ 96.96, 2.099 60 ft.
5) 14.071 @ 96.55, 2.071 60 ft.
Notes: Muffler removed. (system uses 3" Magnaflow cat, no resonator)

Conclusion: I really like that new muffler, sounds and looks good, only cost about a tenth of a second ET. The spark tuning using the IAT table works well at the track and on the street. The intercooler system is much more efficient than the draw-through alcohol system I was using, but since you can make one for about 25 bucks, I still consider it cost effective.
Unfortunately, working the rest of the bugs out of the system will have to wait, as it appears that the supercharger has outlasted the stock engine.
I'll probably follow up on that in other threads.....

[AleroB888]

Originally Posted by AleroB888

5) 14.071 @ 96.55, 2.071 60 ft.

Plan B

Since B888 is down for repairs, I was forced to bring out another vehicle which has been waiting in the wings. This one is an '03 Alero GL, very clean with only 24K on it. This provided me with a chance to get baseline tests and later try out some tuning ideas, but also I want to demonstrate just how much altitude affects performance.

Quaker State ET Series (Bandimere Speedway, April 28, '07) alt. 5860 ft. (ambient temp. 65-75 deg. F)

1) 16.956 @ 81.94, 2.485 60 ft.
(bone stock)
2) 17.120 @ 81.58, 2.521 60 ft.
(swapped in K&N drop-in replacement air filter)
3) 17.117 @ 81.74, 2.526 60 ft.
4) 17.325 @ 81.12, 2.561 60 ft.

The '03 is one or two tenths quicker than the '99 was before modding. The temptation is to just take all the mods off the '99 , transfer them over, and WOOOOOSH!..... into the 13's....

But then again, maybe I'll just settle into a long bench-racing season like everybody else. Maybe start a little trash-talking.....

[AleroB888]

Originally Posted by AleroB888

Unfortunately, working the rest of the bugs out of the system will have to wait, as it appears that the supercharger has outlasted the stock engine.

Interim report:
I'm still shopping around for some 36# injectors, so temporarily the Envoys (28#) were reinstalled, after an LIM gasket change (actually, there are some good technical reasons not to go as high as 42# with an otherwise stock fuel system).
I installed a Fel-Pro metal LIM gasket set some weeks ago, and to my surprise, it seems I now have much more boost than before. I de-tuned the car somewhat, changed the 2.0 SC pulley to 2.2, did a few tweaks here and there, and took a road trip down closer to sea level. I got about 29 MPG highway. I drove 80 miles south of where I am staying to Bowling Green, KY, and got a couple of runs in. I'll fill in the details when time allows.

Beech Bend Raceway Park:
13.816 @ 99.19, 2.096 60 ft.

[AaronGTR]

Originally Posted by AleroB888

Interim report:
I'm still shopping around for some 36# injectors, so temporarily the Envoys (28#) were reinstalled, after an LIM gasket change (actually, there are some good technical reasons not to go as high as 42# with an otherwise stock fuel system).

I'm curious to know what these technical reasons are and where you found them? I and plenty of other people have been running 42lb injectors for some time with no adverse affects. All I have besides the injectors is an AFPR, and although I have a larger fuel pump waiting to go in just in case, the stock pump has not run out of flow yet.

[PhantomLover007]

Crazy yo. Seems as if you couldn't fit anymore in there if you wanted to. Looks nice though.

[tejohnson]

Originally Posted by AaronGTR

I'm curious to know what these technical reasons are and where you found them? I and plenty of other people have been running 42lb injectors for some time with no adverse affects. All I have besides the injectors is an AFPR, and although I have a larger fuel pump waiting to go in just in case, the stock pump has not run out of flow yet.

Aaron, you have to actually give it gas before you max the fuel pump

[AaronGTR]

Originally Posted by tejohnson

Aaron, you have to actually give it gas before you max the fuel pump

Haha, where you been Todd? Oh trust me, I've done a few full throttle pulls with it already. I've just avoided the full quarter mile runs and shifting until I get further along in the tuning process.

[AleroB888]

Originally Posted by AaronGTR

I'm curious to know what these technical reasons are and where you found them? I and plenty of other people have been running 42lb injectors for some time with no adverse affects. All I have besides the injectors is an AFPR, and although I have a larger fuel pump waiting to go in just in case, the stock pump has not run out of flow yet.

I don't have the material in front of me now, but in the book Supercharged! by Corky Bell, two points were made:
1) In his opinion, stock fuel rails could handle an injector increase of about +25%, higher than that may cause uneven flow,
2) The low level resolving ability of the computer, pulse width vs. flow rate may not give a decent idle.
Bell was speaking in general there, and I may not be using the exact technical terms, but you get the idea.

In another thread a very long time ago, you mentioned having some kind of idling issue for some reason, but didn't follow up on it. More recently you posted this:

Originally Posted by AaronGTR

.......I'm using lucas 42lb injectors right now which are good for 400whp. I'll probably never go that high but I've got the room. The GTP injectors will idle better though because of their spray pattern so I'd start with those.

I used the Lucas 42.5#'s through last winter and into the spring. They didn't seem to like starting up cold at 32 Deg. F., or even less than 60 Deg. for that matter.
I was getting misfire codes thrown on every startup in very cold weather. The injectors were only part of the equation, but I suspect them to be the major players.

I realize that a larger injector than 36# may be necessary for max power, but my short-term plan is to get the 36#'s, then try to tune the car to their capability.

[SpyhunteR]

Originally Posted by AleroB888

I don't have the material in front of me now, but in the book Supercharged! by Corky Bell, two points were made:
1) In his opinion, stock fuel rails could handle an injector increase of about +25%, higher than that may cause uneven flow,
2) The low level resolving ability of the computer, pulse width vs. flow rate may not give a decent idle.
Bell was speaking in general there, and I may not be using the exact technical terms, but you get the idea.

In another thread a very long time ago, you mentioned having some kind of idling issue for some reason, but didn't follow up on it. More recently you posted this:



I used the Lucas 42.5#'s through last winter and into the spring. They didn't seem to like starting up cold at 32 Deg. F., or even less than 60 Deg. for that matter.
I was getting misfire codes thrown on every startup in very cold weather. The injectors were only part of the equation, but I suspect them to be the major players.

I realize that a larger injector than 36# may be necessary for max power, but my short-term plan is to get the 36#'s, then try to tune the car to their capability.

My stock fuel injectors were rated at about 260cc right now I'm running 750cc, no idle issue, and on a stock fuel rail, except for the added adjustable fuel pressure regulator.. no fueling issues there..

I believe my resolution seems to be pretty good, and hasn't been showing any hiccups on the dyno whenever the car was last on the dyno for two hours straight.

go for broke man, shoot for hte moon and work out the kinks along the way.

[AaronGTR]

Originally Posted by AleroB888

I don't have the material in front of me now, but in the book Supercharged! by Corky Bell, two points were made:
1) In his opinion, stock fuel rails could handle an injector increase of about +25%, higher than that may cause uneven flow,
2) The low level resolving ability of the computer, pulse width vs. flow rate may not give a decent idle.
Bell was speaking in general there, and I may not be using the exact technical terms, but you get the idea.

Yeah, I've read "maximum boost" by Corky Bell, a similar book. He definitely knows what he's talking about and those are both valid point but also very generalized. They may apply more to older cars or extreme builds. Our modern pcm's have very high resolution because GM has continually increased the processing power over the years, and the stock fuel rails are pretty significant in size and should support a lot of power without an inbalance from one side to the other as long as the pump supplies enough flow. In other words you'd upgrade the pump before making custom fuel rails.

In another thread a very long time ago, you mentioned having some kind of idling issue for some reason, but didn't follow up on it. More recently you posted this:

Originally Posted by AaronGTR

......I'm using lucas 42lb injectors right now which are good for 400whp. I'll probably never go that high but I've got the room. The GTP injectors will idle better though because of their spray pattern so I'd start with those.

While the above statement is true, it doesn't mean the 42lb injectors can't idle well. I believe most of my idle problems where due to other issues. My idle was really bad at first because my O2 sensor was dirty. Then my 65mm TB needed adjustment and I recalibrated the TPS position and that helped. Recently I replaced the granitelli MAF I was using with a stock LS1 MAF and that improved it again. Now I barely have any issue with the idle at all and once I finish VE and MAF tuning I think it will go away all together.

I used the Lucas 42.5#'s through last winter and into the spring. They didn't seem to like starting up cold at 32 Deg. F., or even less than 60 Deg. for that matter.
I was getting misfire codes thrown on every startup in very cold weather. The injectors were only part of the equation, but I suspect them to be the major players.

I realize that a larger injector than 36# may be necessary for max power, but my short-term plan is to get the 36#'s, then try to tune the car to their capability.

Good point. The cold weather could certainly be an issue with the those injectors, probably because of the cold engine and cold fuel and the spray pattern which doesn't atomize as well until the engine is warm. I didn't even think of that since I don't drive my car in the winter anymore, and I probably never will with this car. I've never had any problem at tempsabove 50 though. I think that could have been an issue with your setup. Increasing the idle speed for cold start up and increasing the warm up time and fueling for cold start conditions to warm the engine faster probably could have a addressed the issue, but would take some experimenting to find the right settings.

[lastyear4gt]

Im running 42.5lb/hr injectors with absolutely ZERO idle problems.

[AleroB888]

Originally Posted by lastyear4gt

Im running 42.5lb/hr injectors with absolutely ZERO idle problems.

What are your long-term fuel trims looking like?

[lastyear4gt]

When we tuned the car the were between 0 & -4

[AleroB888]

Originally Posted by AleroB888

.......... I'll fill in the details when time allows.

I used a more conservative setup/tune this time out, since I had the 28# injectors back in. Engine and tranny are stock, added water pump underdrive pulley, 2.2 in. pulley on SC, Autolite 104 plugs, IFR set at 23....ported stock MAF, air filter bypassed.
BFG DRs mounted on Malibu wheels, they are 5 lbs lighter than stock per combo, and one inch shorter diameter....
The SC was peaking out at 10 psi at the intake manifold. As best as I can measure, the Spearco is only causing a bit more than 1 psi loss, but that seems too good, so we'll call it 1 1/2 psi. I am estimating 11 1/2 psi boost out of the SC....
3-inch Magnaflow cat and muffler....this was too loud for me on the trip, so I plan to add a resonator at the end of the year....
IC water iced to around 40 deg, Pressure switch kicks in pump only under boost. This means the IC gets gradually colder during the run.
The transmission tuning and most engine tables remain stock, except Fuel Cutoff RPM vs Gear was raised slightly. All torque management stuff is stock. I am using a switch that forces the tranny to max the line pressure, but I forgot to use it on the first run.
The rest of the tuning you can see in the scan pic below.

Test and Tune, June 26, '07 (Beech Bend Raceway Park, Bowling Green, KY) (temp. 85 deg.)

1. 13.816 @ 99.19, 2.096 60 ft.
2. 13.901 @ 99.19, 2.167 60 ft.
( Lost traction, left the line at too high rpm for the D.R's)
*Session ended due to rain*

This is a scan of the first run:

http://shutter11.pictures.aol.com/da...zrBzw90300.jpg

Just for comparison, I left the setup/tuning exactly the same when I next raced at altitude:

Club Clash, July 21, '07 (Bandimere Speedway, 5860 ft.)

1. 14.985 @ 92.08, 2.263 60 ft.
2. 14.886 @ 92.03, 2.227 60 ft.
3. TPS failed

This is the scan for #1:

http://shutter13.pictures.aol.com/da...qBZiYo0300.jpg

Note how much fuel the PCM pulls out, and the much lower MAF reading and Injector Duty Cycle than at sea level. So what this means is I could use more boost and more timing up here. The problem is, I could not then take that "tune" down to sea level, because the torque limiters would kick in. As it was, the PCM had some trouble adjusting to the sea level conditions after driving 1100 miles from up here, most of that on cruise control. Nothing I'm not used to by now.

[SpyhunteR]

can't you disable the torque limiter nonsense?

[AaronGTR]

First thing you need to do is take out the ported stock MAF since that is a very bad move, especially since you said most of the engine tables are still stock. You aren't getting a correct airflow reading so it's going to screw up your fueling. You can get an LS1 MAF off ebay cheap and just import the table with your tuner. That way you get a larger MAF with an accurate reading for the pcm.

[AleroB888]

Originally Posted by SpyhunteR

can't you disable the torque limiter nonsense?

I'll see if I can go a few tenths lower E.T. before doing that. It's not a factor at my power level now, unless I make a change to the system and the PCM has not had time to adjust itself. But I'm also a beginner at tuning, so I'll stick to the more basic stuff.

[AleroB888]

Originally Posted by AaronGTR

First thing you need to do is take out the ported stock MAF since that is a very bad move, especially since you said most of the engine tables are still stock. You aren't getting a correct airflow reading so it's going to screw up your fueling. You can get an LS1 MAF off ebay cheap and just import the table with your tuner. That way you get a larger MAF with an accurate reading for the pcm.

No, I've been using the ported MAF for over 2 years now, I just never mentioned it before. During that time I did recalibrate it successfully. It did take a lot of time on the road to do it, using a borrowed tuner at first.

I am also not convinced that an off-the-shelf stock MAF calibration won't need at least some changing when it's in a position further from the TB, the TB is larger, the MAP sensor is maxed out at part throttle with low boost, etc.

The LS1 change is a good idea, but in fact at the boost I'm running now, even that is going to restrict the flow. I am using an aftermarket ported LS1 style MAF on loan right now, and doing tests on it.

I think the bottom line is, does the calibration produce the result you are looking for in drivability, and the results at the track....

[PhantomLover007]

Man that thing is nice..

[Sprucegagt]

Originally Posted by AleroB888

No, I've been using the ported MAF for over 2 years now, I just never mentioned it before. During that time I did recalibrate it successfully. It did take a lot of time on the road to do it, using a borrowed tuner at first.

I am also not convinced that an off-the-shelf stock MAF calibration won't need at least some changing when it's in a position further from the TB, the TB is larger, the MAP sensor is maxed out at part throttle with low boost, etc.

The LS1 change is a good idea, but in fact at the boost I'm running now, even that is going to restrict the flow. I am using an aftermarket ported LS1 style MAF on loan right now, and doing tests on it.

I think the bottom line is, does the calibration produce the result you are looking for in drivability, and the results at the track....

An LS1 MAF will not restrict your airflow at low boost levels, meaning anything below 10 PSI. The only thing porting a MAF will do, is screw up it's readings.