A.Wayne

Are you sure 200 c or 200 F. @ 200c you would have a lump of protoplasmic alloy sitting in the engine compartment.

pzull

[QUOTE=DonE]
We ran through nearly every cell from idle to full boost and mapped the exact AFR for each cell (remember, I've been street tuning) - what fun. It took nearly 2 hours to map the AFR's, so we did not get to the ignition.QUOTE]

What AFR do you target under below scenarios:
1) Rpm Range
2) Heavy load acceleration
3) constant speed cruising
4) coasting - lift off throttle completely?

Do you use the same AFR number for all above scenarios or are they different? I need to learn as I will be embarking on EFI project in a month's time.THANKS

DonE

[QUOTE=pzull]Here is an idea of how I just set the car up on the latest dyno run:

> 0 - 70 kPa - mid 14's (cruise)
> 70 - 100 kPa - high 13's
> 100 - 150 kPa - mid 12's
> more than 150 kPa - 11.8 to 12.0

I have accel enrichment set up to provide 11.8 at WOT, regardless of kPa.

On full decel, I have the injectors turned off, with about 4% additional fuel shot in the cylinders immed when the inj turn back on. Of course, in this case the AFR is off the chart (high) until the injectors come back on. On gentle decel, I have the min inj time set to 1.2 ms to give me a smooth coast.

I understand these are general numbers, but every engine is a bit different - turbo efficiency, IC efficiency and so on. Since these are air-cooled engines, I am more interested in thermal management (longevity) than peak HP. Although I've been messing with my engine and tuning it myself, its my first air-cooled turbo motor. You need to hook up with an experienced tuner for best advise.

PT

Well, that's the temp right after the turbo before the intercooler. I know the sensor is accurate @ -3C, 20C and 100C. So I assume its accurate up there as well.

A.Wayne

Intake temp should be measured as close as possible to the intake manifold , not at the turbo output.

pzull

[QUOTE=DonE]

Here is an idea of how I just set the car up on the latest dyno run:

> 0 - 70 kPa - mid 14's (cruise)
> 70 - 100 kPa - high 13's
> 100 - 150 kPa - mid 12's
> more than 150 kPa - 11.8 to 12.0

I have accel enrichment set up to provide 11.8 at WOT, regardless of kPa.

On full decel, I have the injectors turned off, with about 4% additional fuel shot in the cylinders immed when the inj turn back on. Of course, in this case the AFR is off the chart (high) until the injectors come back on. On gentle decel, I have the min inj time set to 1.2 ms to give me a smooth coast.
QUOTE]

WHat are these numbers in kPa? Manifold Pressure? Sorry I'm new to thiis.
I will have a tuner doing my car but he does all sorts of cars and not specialised in air-cooled engines which I have been told are different
Thanks for the info

PT

I am measuring both before & after The after # is more like 50-70C at that temp going from memory right now.

DonE

[QUOTE=pzull]Air cooled is very different from water cooled. Be very careful as some of the small turbo motors (WRX for example) is at 30 lbs (approx 300 kpa) with big timing. You will melt your motor if its not built for that.

kPa stands for kilopascal - 100 kPa = 14.7 psi = atmospheric presssure at sea level on a standard day. Anything below is pulling a vacuum and anything above is positive pressure (boost).

m.lovell

You guys seem to know your stuff with efi so I hope its ok to ask a quick non porsche related question.....
I`ve just built a new 3.5 lt motor for my 1972 bmw 3.0 csl. Its belt and braces, special crank, carilo rods, forged pistons ect ect ect. My efi man insists that I don't need to run a lamba probe. So far on the dyno its pulling 290 bhp @6200 rpm (on a test bed,fly wheel with no alternator or power steering pump ect)with a good torque curve with out a lamba probe. I have for estetics had to keep the original inlet system and throttle body (all gas flowed to match the enlarged and flowed ports on the head) but am running high impedance injectors (un like low impedance d-jet). I wanted the car to look as original if you lifted the hood.

could some one please explain why i do /or don't need a lamba probe, I am getting out of my depth ....
marc

im4duke

I'm sure someone here could answer for you, but you might also try http://www.efi101.com/forum/

A.Wayne

I'm not sure why myself , egt's , lambda etc are just tools for providing information in making tuning decisions. 280 bhp is reasonable for a 2 valve 3.5 , have not seen a 3.0 in awhile , my E-46 328 stock intake but with cams , pistons and exhaust , ecu made 278 WHP ( 325 @ FHP) spun to 8000 rpm.
Regardless of the engine type , your EFI guy would be the person to tell you why he does not want A/F ratios, as it is always good to have a reference..

PS. like the collection, saw the gallery !

__________________________________
www.tpgproducts.com

nathanUK '81 930 G50

Marc, does he mean he doesn't want the sensor controlling the A/F ?

I bought a K&N A/F sensor and gauge for my 930 but now I know I really need a wideband one.

I want to check my A/F or CO when ever I want to by just looking or recording the gauge (with my camera that takes movies, need to get a camera mount). Checking the A/F could help prevent a lean condition and damage to the engine.

Dknebes

Don what numbers are you running in the acceleration enrichment also what numbers are working in your idle tables and starting enrichment's? Do you run a 4 wire IAC if so did you find any change if you adjusted the min/max duty/cycle? My car normally takes two tries on a cold start. I am running Electromotive version 3.4.1

Thanks
David

DonE

Here are the settings from the TPS/MAP accel enrichment window (V 3.4.1), top to bottom:

on
on
13
3
0
6
0.5
0
30
10
0
0

Start enrichment top to bottom:

66
4
1.3
32
35
8
10

Idle speed control, top to bottom:

on
four wire
150
150
65
95
10

Min/Max Duty Cyle
40
185
allow idle motor box checked.

Yes, I run the 4 wire electromotive stepper motor and I did have to change the min max - lower actually so it would close fully. When I spoke to Nic at electromotive, he said the initial numbers in the manual are guidelines. With these settings, the car starts cold perfectly and idles immed. The idle speed vs temp is: 1650@-30, 1450@10, 900@70. For whatever the reason, the idle will never get below 1050 unless I retard the timing. Initial timing is 11 degrees.

Good luck.

Dknebes

Thanks Don, I will try these setting. I also have trouble getting my idle down. When I talked to Joe Essa he said you should not get your rpm to low at idle because off oiling for I believe the valve springs. I am not totally sure why that would not be true with a stock engine but I follow his directions. I will let you know how your settings work.

David