79 replies to this topic

[EricF]

Jardon, on 19 November 2009 - 05:33 PM, said:

Just to add - a 19t is only above 65% efficient with my boost plot from around 2500 to 6000 rpm. Above 6000 rpm even with only a bar of boost it is off the compressor map (inefficient). The same goes for all TD04 turbos - but less efficient for say a 15g which can only flow less for a given amount of boost. The high rev/high boost will not be nice to drive and will bugger something eventually. Go with lower boost, as many flow mods as you can afford and a good tune.

I think you may be making some hasty calculations. What are you using as your VE constant? With the TD04HL and especially stock manifold, VE is way down above 4500 or so. It peaks in the 3500-4000 range...

[ozzimark]

EricF, on 19 November 2009 - 07:44 PM, said:

I think you may be making some hasty calculations. What are you using as your VE constant? With the TD04HL and especially stock manifold, VE is way down above 4500 or so. It peaks in the 3500-4000 range...

Blasphemy! Everyone knows the stock whiteblocks see a VE of around 1.2 at redline!

Seriously though, the 19T should be doing up to around 1.5 bar before it gets close to the choke limit of the compressor with the engine at redline, if not more. The VE of these engines is so bad that I've noticed airflow actually DROPPING with increased rpm past ~5k or so on the stock setup

I think it's time for some velocity stacks and a tubular manifold on my engine

[turbor850]

L8 APEKS, on 19 November 2009 - 04:55 PM, said:

???

Quote

22-23 psi steady and spiking to 25-26 no issues. So I decide to do a hard launch and brake torque from 2500. I hit 7500 in first and then have a massive explosion

Auto + 7500 + what tune ?

[PsychoWagon]

I'm running 22psi with turbonetics mbc and a st tune. I'm hitting fuel cut when it spikes though, I was quite frustrated with the fact that I hit fuel cut with a ST tune... unless its my ignitio system DEAD missing... MSD Blaster coil tho... hmmmmmm I'm wondering now, fuel gauge on tomorrow.

[L8 APEKS]

Man, one of you guys needs to have your laptop hooked up to your OBDII and go flog your car, watching the spark advance on one of the free ODBII scan programs (EasyOBD, OBDIISpy, etc). I'd be very surprised if you're getting full advance at 22+ psi on 91-93 octane. Well, maybe 93...but us CA guys who only have 91 have got to be suffering in the spark advance department!

[HeavyIron]

L8 APEKS, on 19 November 2009 - 06:40 AM, said:

I'm just saying...ain't NO way he's getting full timing advance (more likely quite a bit of retard) on pump gas at 23-26psi unless he has meth injection running 100% of the time, or he only fills up with 100+ octane.

Car would probably be faster with less boost and more timing advance on pump gas.

...unless there's something magical about Motronic that I don't know about, anyway. heh.

45 degree ambient temp the night I was running. the day I had my car dynoed (few weeks before) I t did 40+ degrees of adv at 7500 rpm peak hp of 294 was made at just over 7000rpm running 16psi b/c factory wastegate actuator would not stay closed.

turbor850, on 19 November 2009 - 12:28 PM, said:

Speaking of your car, where's that dyno ?


and to OP, you hit 7500 with your auto on what tune ?

MTE tune. Marco called me back 25psi tune with 7500 rpm limiter

[Captain Bondo]

HeavyIron, on 20 November 2009 - 05:37 AM, said:

45 degree ambient temp the night I was running. the day I had my car dynoed (few weeks before) I t did 40+ degrees of adv at 7500 rpm peak hp of 294 was made at just over 7000rpm running 16psi b/c factory wastegate actuator would not stay closed.



MTE tune. Marco called me back 25psi tune with 7500 rpm limiter

If you're making peak power at over 7000rpm with a TD04 and stock cams, something is up. That makes pretty much no sense at all. 40 degrees of timing advance at 16psi also sounds... odd...

[HeavyIron]

GeraldJ, on 19 November 2009 - 04:12 PM, said:

Im not trying to be harsh. I am just saying.

I know guys running 30+lbs on single and twin turbo cars and trucks and dont run such a hard spring in the gate. My brother in law has a twin turbo small block with each turbo running 25lbs and he only uses a 12lb gate spring in each.

Just because you want to run 22lbs does not mean you use a 22lb wastegate. The boost curve will be to sharp and will cause problems. Boost has got to come on progressively or the ecu cannot factor for it.

When you brake boosted to 2500 you already had 20lbs built up and then you just let it go on the poor motor just getting up to speed. Kind of like swinging a 12lb sledge hammer at a pinata.

If I remember in your build you used OEM pistons and forged rods. The pistons are the weak link. If you used a stock rod you could put a string on it and shoot arrows from it by now. The problem now is you have a peep hole in your piston.

I got lucky- I will post up pics as soon as I can find the cable for my camera. Pistons, cylinder walls, and valves all look superb. their is a 1/4" piece of hg missing around cyl #2 where it blew out. the head bolts were measured and the bolts had stretched a couple .001's around cyl 1 &2. Basically, the head lifted off. I have seen it happen in boosted hondas and eclipses. Thankfully the head gasket gave out first and pressurized the cooling system blowing out my radiator. If the gasket had held, My valves and pistons would be destroyed. I count my blessings. I will have to spend more time tracking down my misfire / detonation problem. I agree my WG may play a part, but it is not all of it b/c the problem was there prior.

For the non believer here is my first run dyno @ 16 psi max

[JCviggen]

To say that's a weird dyno would be an understatement. Not sure how much it proves. It doesn't make much sense. I have seen many MTE tunes including my own and even with big turbos they drop off because Marco has the last rpm point at 6200 with (too) much advance.

[GeraldJ]

JCviggen, on 20 November 2009 - 11:25 AM, said:

To say that's a weird dyno would be an understatement. Not sure how much it proves. It doesn't make much sense. I have seen many MTE tunes including my own and even with big turbos they drop off because Marco has the last rpm point at 6200 with (too) much advance.

That and your MTE tune runs perfectly in my car



You did get lucky, I would still take that wastegate spring and toss it out for something a bit smaller. 15lb at the most

[EricF]

HeavyIron, on 20 November 2009 - 05:45 AM, said:

I got lucky- I will post up pics as soon as I can find the cable for my camera. Pistons, cylinder walls, and valves all look superb. their is a 1/4" piece of hg missing around cyl #2 where it blew out. the head bolts were measured and the bolts had stretched a couple .001's around cyl 1 &2. Basically, the head lifted off. I have seen it happen in boosted hondas and eclipses. Thankfully the head gasket gave out first and pressurized the cooling system blowing out my radiator. If the gasket had held, My valves and pistons would be destroyed. I count my blessings.

Did you check flatness of the head and block? I am still sure it had nothing to do with the bolts...

[lookforjoe]

JCviggen, on 20 November 2009 - 11:25 AM, said:

To say that's a weird dyno would be an understatement. Not sure how much it proves. It doesn't make much sense. I have seen many MTE tunes including my own and even with big turbos they drop off because Marco has the last rpm point at 6200 with (too) much advance.

Jan said the same thing about the fuel calibration point - 6200 is the last plot.

In all my data logging, timing is significantly closer to TDC once you go WOT

... the timing advance here is at this 4/5 shift point, otherwise it's only a few degrees advance..

time RPM AFR MAF speed

[GeraldJ]

update?

[Captain Bondo]

JCviggen, on 20 November 2009 - 11:25 AM, said:

To say that's a weird dyno would be an understatement. Not sure how much it proves. It doesn't make much sense. I have seen many MTE tunes including my own and even with big turbos they drop off because Marco has the last rpm point at 6200 with (too) much advance.

I was trying to think of how to say the above- the dyno plot is just... weird.

The whole scenario just doesn't add up/ I don't know why, and I'm not saying the guy's car sucks or anything, but something weird is going on.

My T6 makes peak power lower than that, with a tube header, hotter cams, and a hugeass turbo.

Did all of the dyno plots look like that? Mind you if they were all on the same setup the same day they might all have the same 'whateveritis" throwing them off...

[volvo500bhp]

JCviggen, on 20 November 2009 - 11:25 AM, said:

To say that's a weird dyno would be an understatement. Not sure how much it proves. It doesn't make much sense. I have seen many MTE tunes including my own and even with big turbos they drop off because Marco has the last rpm point at 6200 with (too) much advance.

Hi Jc

How much ignition did your car have when it used to be on an MTE map ? it would seem this is not the first mte tuned car that has lunched a headgasket...

Russ

[Jardon]

volvo500bhp, on 21 November 2009 - 07:32 AM, said:

Hi Jc

How much ignition did your car have when it used to be on an MTE map ? it would seem this is not the first mte tuned car that has lunched a headgasket...

Russ

I would have thought mte's (or anybodys) tune would be irrelevant to the HG issue when the OP is running a 22psi wastegate. I checked mine last night and it starts to open at 4-5 psi. I hold 1.4 bar to 5000 rpm and then it tails off as the turbo gives up. You just don't need that much actuator strength and any subtle boost control would have been out the window. Interested in the lunched HG's though - who was that?

[550]

I think it may not have been the bolts solely, but a combination of things :-/

[JCviggen]

volvo500bhp, on 21 November 2009 - 07:32 AM, said:

Hi Jc

How much ignition did your car have when it used to be on an MTE map ? it would seem this is not the first mte tuned car that has lunched a headgasket...

Russ

Hey Russ

27 degs BTDC at 6200 (the last rpm plot). Mind you my car never had an issue with it and made great power, but MTE relies on some timing pull halfway to end up with an acceptable value at high rpm's. A better way to tune is avoid timing pull anywhere and use the correct values. MTE's way takes less time to tune no doubt, but it relies on timing being pulled and ending up considerably lower than what's programmed.

[Jardon]

JCviggen, on 21 November 2009 - 05:56 PM, said:

Hey Russ

27 degs BTDC at 6200 (the last rpm plot). Mind you my car never had an issue with it and made great power, but MTE relies on some timing pull halfway to end up with an acceptable value at high rpm's. A better way to tune is avoid timing pull anywhere and use the correct values. MTE's way takes less time to tune no doubt, but it relies on timing being pulled and ending up considerably lower than what's programmed.

I have no idea when it comes to timing what a desirable set of values might be. I remember you saying a while ago before I fitted my 19t that I'd be better off running 1.3 bar than 1.4 - is this because you have to pull timing at that level of boost? What are you calling the correct values? I might get hold of Tim Williams VCT and look at the timing one day.

[turbotuner]

Jardon, on 21 November 2009 - 09:15 PM, said:

I have no idea when it comes to timing what a desirable set of values might be. I remember you saying a while ago before I fitted my 19t that I'd be better off running 1.3 bar than 1.4 - is this because you have to pull timing at that level of boost? What are you calling the correct values? I might get hold of Tim Williams VCT and look at the timing one day.

I can't remember all the settings that the VCT can log, but you need to know whether or not timing is being pulled. If the VCT doesn't tell you how much ignition retard is applied, then you will need to know what the timing is set to in the map and compare it to what the VCT is reading.