engine and drivetrain Tii Rough Idle And Mixture Question

[jgerock]

Scott - I'd leave well enough alone if YOU are satisfied with how your car performs.  I've driven a handful of tii's and can say that NONE of them performed the same.  I even drove an early 72tii with CR trans. and it seemed slow to me.

 

So far, the best performing 74tii that I have driven was Keith Kreeger's (almost all new with 5 speed and 3.91LSD) in Kansas City a few years ago. I need to make it a point to ride in (or drive) Bo Black's and Bill Williams' tii's with Alpina ITB injection.

 

Jim

[saaron]

That's where I'm leaning, Jim.  I know - Bill's A4.  Good lord.  That car is nice.  Hope to see some nice ones at Vintage!

 

Scott

[bnam]

Scott - I'd leave well enough alone if YOU are satisfied with how your car performs.  I've driven a handful of tii's and can say that NONE of them performed the same.  I even drove an early 72tii with CR trans. and it seemed slow to me.

 

So far, the best performing 74tii that I have driven was Keith Kreeger's (almost all new with 5 speed and 3.91LSD) in Kansas City a few years ago. I need to make it a point to ride in (or drive) Bo Black's and Bill Williams' tii's with Alpina ITB injection.

 

Jim

 

Or you could follow my motto... "if it ain't broke, fix it... now it WILL be broke"  

[lilmo]

Or you could follow my motto... "if it ain't broke, fix it... now it WILL be broke"  

+1!

Edited February 12, 2014 by lilmo

[classicman]

Thanks again for the responses guys.

 

I'm of the opinion that my car is overfueling rather than running lean.  When I set the COs at 4,000rpm in the garage using my Gunson, she starts to smoke - not black smoke.  The motor is new, so she is not using oil, but my thought was that if she is fluffing because she is overfueling (plugs are black as well, even after a longish run on the highway), and this is causing the fuel to wash the cylinders of excess oil.

 

The way I see it is that I have two options for now - rolling road Dyno or AFR gauge to start with.  Judging by the comments on all of the other threads I have read, the AFR is the way to go. I'd be too worried about causing damage on the Dyno without knowing what the car is actually doing.

 

I'll keep you posted once I have ordered and fitted the AFR.

[thehackmechanic]

I bought a Gunison as well, but did not find it terribly useful for anything other than a gross check at idle. I have an old portable exhaust gas analyzer I bought at a pawn shop 30 years ago, which is okay to get a relative reading, but it drifts pretty easily, and actually using it -- having the sensor stay in the tailpipe while you stretch the wires into the passenger compartment -- is a bit challenging. The AFM solves all those problems. You'll love it. And hate it, because it tells you the truth.

 

One caveat -- Dave Redzsus says "data never lie, but data don't always tell the truth," or something like that. What he means is that the AFM actually doesn't measure anything to do with fuel -- it measures oxygen in the exhaust. So you just need to be sure that other things aren't throwing that off, like a cracked exhaust manifold, or a gap in an exhaust joint close to the UEGO sensor.

[kaptanoglu]

The AFM solves all those problems. You'll love it. And hate it, because it tells you the truth.

 

I just ordered one of these from Top End Performance (who built my motor):

http://www.aemelectronics.com/wideband-air-fuel-systems-15/x-wifi-wideband-air-fuel-uego-controller-egt-monitor-34/

 

I was torn on where to put a gauge, and being able to pull it up on the iPhone is a great solution if you don't want to add a gauge and don't  want to stuffy anything else in your glove box.

 

We did a few things with the motor that many on this list suggest were bad ideas, and in the next few weeks, we will see if, in fact, you can get a modestly modded tii motor to idle and run well.  I will have it at MidAm, so I can be heckled/admired in public.

 

Good luck.

 

J

[lilmo]

I bought a Gunison as well, but did not find it terribly useful for anything other than a gross check at idle. I have an old portable exhaust gas analyzer I bought at a pawn shop 30 years ago, which is okay to get a relative reading, but it drifts pretty easily, and actually using it -- having the sensor stay in the tailpipe while you stretch the wires into the passenger compartment -- is a bit challenging. The AFM solves all those problems. You'll love it. And hate it, because it tells you the truth.

 

The guy that rebuilt my kfish told me not to bother with an AFM.  Like hiring a PI to follow your spouse if you think he/she is cheating.  What are you going to do about it when the results come in?

Edited February 17, 2014 by lilmo

[kaptanoglu]

The guy that rebuilt my kfish told me not to bother with an AFM.  Like hiring a PI to follow your spouse if you think he/she is cheating.  What are you going to do about it when the results come in?

 

In my case, we have made several modest changes, including a cam change (to a 284).  We are going to see how it runs, and if we can't get it running fantastic through the rev range (with the AFR as one measure), I am going to kick that cam to the curb like the cheating piece of crap it is (if, in fact, it is).

 

What I hope is that we can get it running great through the rev range and then we'll put it on a dyno to see if we got anything out of the mods, because, as they say, "De dyno don' lie."

[jgerock]

The guy that rebuilt my kfish told me not to bother with an AFM.  Like hiring a PI to follow your spouse if you think he/she is cheating.  What are you going to do about it when the results come in?

Not sure I follow that logic.  I would still be guessing and my car would run like crap if I did NOT install a WB AFM.   

 

Now, if you had a professional tuner rebuild your tii and "tune" it for maximum performance  - that is another story.

[jgerock]

I just ordered one of these from Top End Performance (who built my motor):

http://www.aemelectronics.com/wideband-air-fuel-systems-15/x-wifi-wideband-air-fuel-uego-controller-egt-monitor-34/

 

I was torn on where to put a gauge, and being able to pull it up on the iPhone is a great solution if you don't want to add a gauge and don't  want to stuffy anything else in your glove box.

 

We did a few things with the motor that many on this list suggest were bad ideas, and in the next few weeks, we will see if, in fact, you can get a modestly modded tii motor to idle and run well.  I will have it at MidAm, so I can be heckled/admired in public.

 

Good luck.

 

J

No heckling is allowed if you put forth the effort to make your combination work.  I only posted that technical correspondence letter from the older Roundel for information purposes.  As described on this forum multiple times, you should tune your tii as outlined by the factory procedures, then make the necessary adjustments based on your engine's overall condition and needs. 

[kaptanoglu]

No heckling is allowed if you put forth the effort to make your combination work.  I only posted that technical correspondence letter from the older Roundel for information purposes.  As described on this forum multiple times, you should tune your tii as outlined by the factory procedures, then make the necessary adjustments based on your engine's overall condition and needs. 

 

I really appreciated seeing the Tech Cor letter, as it reflected what I have heard from a number of folks whose opinions I respect.

 

Being the idiot that I am, and being a former E36 M3 owner (where the US was cheated out of about 90 bhp vs. the Euro version), I look at the Euro 2002tii with its 10:1 pistons, and think, "I want those", and how they dumb down performance for idiots that put mid-grade gas in the tank.  Once you punch it out (2 mm over) and put in the 10:1 pistons and port the head, it's like "a littttle bit of cam can't hurt" even though some people say, "yeah, a little cam can hurt a lot".  An headers?  Hell, yeah!

 

So Lisa and I will arrive at MidAm with a sparkling restoration that will either -a- be very quick, and the envy of all my new friends, or -b- be very loud and idle like a diesel, making less power than stock, in which case, a stock cam goes back in.

 

I can't wait.

 

J

Edited February 18, 2014 by kaptanoglu

[SydneyTii]

Great thread!

I have a euro spec 74tii so it's compression ratio is higher than the cars that were originally sold in the USA, well according to Mike McCartney ( I think) and yes he was a bloody marvel with 02s, I spent many a rainy Saturady morning at Jaymic in the 80's and he never ceased to amaze me how much assistance he would offer and advice he would give, great guy and sorely missed from the 02 community. I spoke to him on line a couple of years ago when he was minding what is left of Jaymic, which is now run by his daughter ( who is equally helpful) he rides a motorbike now as the traffic in the uk leaves a lot to be desired, but I reckon he still has his supercharged 02 somewhere ;-)

Anyway a bit off subject, but if he said he did it with a 300 degree cam then you can bet he did, but I bet it was as Lars said and an Alpina one.

My brother in law had an A4s we stumbled across it flat tires tired paint etc but my god it stuck out like the proverbial sore thumb. He got it running beautifully, and it went very well, but I have to tell you that a well sorted euro spec Tii is also a very nice car, it's smooth, powerful and punchy, the A4s was very torquey and pulled well right through the rev range, but it could be a bigger to get going when cold. It also had the beefed up suspension etc so again was not as nice a ride (each to their own here)

I would just stick to the standard cam and lose the 300 degree or you will quite a bit trying to get it to run right, I have seen the classicmans car in an article in BMW car I think, it looks lovely, I don't think you should get too worried about the Alpina induction system etc they are now a bit silly in terms of price. I have a friend here who has done a few things to his Tii, gapless rings, small oversize pistons, larger vales and triple cut, RHD tii standard exhaust, Petronix and most likely other stuff I have forgotten and at last dyno he was achieving 150bhp without sacrificing any drivability, remembering he had 130 to start with as a standard euro spec tii, that seems just right to me.

Anyway apologies for the rambling

[SydneyTii]

Btw I have an innovate AFR, I would highly recommend one, my Gunson was ok for setup at idle but I needed something to measure the full range.

[classicman]

Thanks for the info, and yes, it was my car in the UK BMWCar magazine.

 

I have ordered an AEM 30-5130 unit and will couple up and see what she looks like when I get it.

 

I have phoned Jaymic and spoken with Pete and their workshop manager.  They weren't too much help, so I'm going to try and get Mike's number.

 

Call me stubborn, but I'm going to keep on trying until I either get it right or die trying :-)