Captain Bondo

Oh crap you still have the breathe rplumbed in pre-turbo? I was talking about sucking oil out through the compressor seal, but if you actually still have any hoses connectect to the crank case plumbed to the turbo inlet, that won't help either. That is bad bad news if that's the case.

What does your inlet tract into the turbo look like? The turbo can make vaccuum in the compressor inlet if the air filter/etc are too restrictive. This will suck oil into the compressor inlet.

Sounds about right. Make sure you move the timing values as well.

No point in trying to adapt a different sensor. It sounds like a job for a 3" piece of aluminum pipe, a drill, and some epoxy. True enough on the afr vs fuel map value JC. Same can be said for map sensed systems where the desired boost pressure is slightly higher than the max the MAP sensor can read - you set the values to whatever is correct for max boost and it's just a bit rich/retarded for the few psi before that. Getting some numbers at 15psi, and at 18psi or something like that has been mentioned by a few folks now and to re-cap, I'd say that is good advice. Even 12, 15, and 18. Try to get a feel for what the car does as boost increases. Determining if/how/when the motor starts to underperform as boost is added will help narrow down what the issue(s) is(are).

Seems like a chunk of 3" intercooler piping and some epoxy should do it. Scale the fuel values up by the same % difference in cross sectional area per the 3" pipe vs the stocker and it should easily be close enough to drive and re-tune.

That's fine, except that he has no idea how much airflow is increasing as he adds boost after the point where the maf maxes out, and it still doesn't explain why the timing is not what is has been mapped to.

I'm always worried when I see a torque curve like that - when you get peak torque at exactly the point where you first hit full boost, and then it starts falling off hard immediately after, something is up. It would be good to see a pull at 15psi. What it means is that you have a problem that gets consistently worse with either airflow or rpm, or both. It could be electrical/tuning or it could be a flow restriction. Since you're only making 260whp it's probably safe to say it is a electrical/tuning issue. Unless you have screwed up you cam timing really badly. That would do it too. When I had the crappy ignition drivers in my car for my first (and smilarly disappointing) dyno trip, it did the same thing. An EGT probe before the turbo would reveal this. It may well be a combination of things - weak ignition, sub-optimal tune, sub-optimal cam timing, etc. I went from a similar torque curve to you and 280whp to a much nicer curve at 388whp and although I did change the cams, most of the gains were from the ignition improvements andfcam timing. Small seemingly insignificant things really. The devil is in the details.

I think it's funny you guys think 5 degrees at 24psi represents tons of timing pull. That's about right actually. The car is down about 100whp from what it should make. Here's a hint: 5 or even 10 degrees of timing won't cost you 100whp. There are other things happening here. You never did any pulls at lower boost levels? Regardless 260whp at 24psi is more than a timing issue. Especially since it made less on the woth tune than it did before as well. A pull at 14-18psi would have been very very helpful.

That sucks man, sorry to hear it. That said, as I have said before, I can't see how the TT is compensating for the maxed out MAF either, so I'm not suprised. In fact I've sounded like a broken record commenting on the maxed out MAF for the last few months for the same reason. I know JC's car works but I just can't see how you can tune properly when the load signal is maxed out. What's up with the documentation for TT? Do they not explain this? How can you sell something and not explain the adjustments? There should not be any confusions on this. There should be a cut-and-dried explanation and procedure for how the car is tuned once the MAF maxes out. Failing that I really think the MAF needs to be in a bigger housing. Go back to page 15 and re-read up to page 18 or so where I try to explain that however TT is handling the maxed out MAF, it doesn't seem to make sense or be very clear.

Interesting about the clutch. I'm very interested to see what you make -24psi should be enough boost to send one of these motors into orbit! I assume you have the 10cm turbine housing if it isn;'t spooled up till 4000rpm. If that's the case and you're making less than say, 7 more hp/psi between 20 and 24psi, you could probably put a 25g compressor on it- pick up some efficiency and not change spool much. But anyways looking forward to the numbers, I hope you get want you want, you've been working hard at it that's for sure!

I'm interested to see how much hp you pick up between say, 20psi and 25psi. I'm betting not much... I think 350awhp is pretty much going to max that thing out... You need a 35R. Probably lose 500rpm of spool and pick up 100hp. :lol:

Interesting. So it sounds like TT's definition of 100% load and the OT1's definition are different. Can you drive the car at a semi-consistten 25%, then 35%, then 45% etc load using the map trace on TT, and then compare the datalog and see what it records for load? In order to tune effectively the load point on the log needs to be reporting the same point the TT is.

I bet this has been asked before -but can you log knock events?

4 degrees works well for me too and I don't lose any top end. 6 degrees I lose a bit. more than that and the car makes less power everywhere. I haven't seen much for gains moving the intake around. I like it straight up.

Yeah leaving them plugged in and unbolted would be a nice thing to try. I mentioned pulling a bunch of timing form the map, but yeah as you say in addityion to that I would definitely turn the boost down too. If the knock sensors are messing with the timing and AFR who knows what the tune will be like once you take them out of the loop. I think that is an excellent idea.

Does it crap its pants if you unplug the knock sensors or can TT bypass that? Would be nice to tyr it with no knock input. Retard the whole map 10 degrees to be safe and then go from there with no knock sensors.

You of all people should be beyond this sort of reasoning by now. Sure maybe it "works". Look how many years everyone on tbricks said the 90+ "works". Now it's a given that the 90+ leaves a lot of power on the table. Even guys making bigger power like Peter L that were used as "proof" that the 90+ "works" eventually converted and picked up like 50whp and would never say that now. The bottom line is even the fastest cars here have mediocre power outputs compared to what most guys with other makes are doing, and they bend rods very easily. Nobody even seems to know how the basic engine control works and you're all blaming the rods. The fact that most are convinced convinced that the rods suck and bend on their own and aren't even very safe for 300whp speaks volumes. I'd be shocked if the rods weren't good for 350-400whp but the way things are "tuned" around here is so FUBAR'd no one will ever realize it. Based on my motor I've already shown they're quite happy around 325whp (based on the hp per rod my motor makes) and I only stopped because I ran out of fuel. Sure blame it on a bigger hotside and no "low rpm boost spike" if you want, but the bottom line are there are some basic issues going on that no-one can seem to define that are holding most guys up bigtime. If you don't wanna hear it then fine but I'm trying to make a point not just be an asshole. :)

If no one here can say something like Pulsewidth = Load*Map-point + K1*IAT + K2*CLT + K3*MAP or something then nobody knows what's actually happening unless you can datalog or scope injector pulsewidth.

This discussion is and will continue to be meaningless and go in circles until someone just explains how Turbotuner/Motronic 4.x actually calculates injector pulsewidth. If someone who knows would explain it, I think lots of people would benefit, because it's clear there is a lot of misunderstanding going on. I'm just basing my comments on how most MAF based ECU's operate. If I don't have all the facts, fine, but enlighten me rather than just saying I'm confused or don't know the facts.

You are absolutely wrong. 15psi at 1/3 throttle and 15psi at WOT is exactly the same unless you have iITB's. ITB's change port dynamics and VE relative to their position. How do you think MAP based engines even function? They don't care about throttle position. They only use it for accel/decel enrichment. If there is 15psi in the intake, the injector duty cycle will be at a certian level. That level wil not change based on TPS. The AFR will be the same. I could prove it with datalogs except that my MAP based car doesn't even have a TPS, it doesn't actually need it. How are we even arguing this point? It's as basic as it gets....

here are lots of high powered cars running carbs too. Saying that expecting an EMS to be able to vary fuel and timing with boost is being too anal? Seriously? You cna get nearly the same effect with 5 cold start injectors and just switch them all on at once when you go over 15psi. Add/remove cold start injectors as needed. It's an only slightly less adjustable version of the same thing. Will it work? Sure. The car will run ok being way rich and way retarded when you have pegged the maf but not yet actually hit the load point you have tuned everything for But the car's power under the curve (and I don;t mean under the rpm curve, I mean under varying manifold pressures) will suck, egt's will be way higher than necessary, and gas mileage will suffer. I think to replace the maf with a map you'd need to use a maf eliminator kit that also involves a second IAT senssor. It would have to use the IAT and MAP to send out an "equivalent" load signal (the MAP signal would need to be density corrected).

15psi in the intake is 15psi in the intake. It makes zero difference where the throttle is. You are measuring pressure in the intake, after the throttle body. You can't use the TPS in this case - manifold pressure is what matters. Ugh...

Because boost does not transition instantly from 0 to max, and you don't always give the car enough throttle to acheive max boost. In those situations the car will be way rich. Just becuase my wastegate is set at say 20psi does not mean I don't have a lot of times when the car is at 15psi or 18psi, making less hpo and therefore needing less fuel, but the ecu would not be able to tell. The timing will not be anywhere close to optimal either. Timing retard should to change consistently with load.

Yes it's just the flow rate the electrical signal maxes out at. Re-read my post above. Hence my saying it's the scale of the electrical signal that matters. LookforJoe, It's looking better and better. :)

Ah I see. I didn't realize you were referencing JC's car. Maybe it is scaled electrically as well or something. That is sometimes an option as well but then you really do start to lose the low load cells to a larger degree.