But wouldn't it be cool!
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TH400 Switchable stall results
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What was the starting temp?
Is this a V6 or V8 procedure? If it's V6, it might work with a turbo smaller than mine, but wouldn't work for me.
That's going to depend a lot on the turbo/converter combination.
turbobitt
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turbobitt
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Keep in mind that this is a project that started just to keep me busy. I have nothing to loose if it doesn't work. Just having some fun with it for now. At the very least it is a really good learning experiment.
Allan G.
turbobitt
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Chris's transmission dyno doesn't have an integrated cooler. We also didn't test under any significant load on the dyno and was only looking for functionality.
For the temps I listed above, that was in car data with a conventional radiator cooler only. Ambient temps were also low at about mid 40's. I'm sure the outlet temps are way higher than the sump but I don't have any extra channels to monitor that temp. I may need to reassess that if I get serious in using this system.
Allan G.
I think I would be more interested in the 'cooler out' temp than the sump temp.
I was just thinking. Could an engine tune be run more to the limits on a pass, if you didn't have to spend 7+ seconds stalling on the TC to get the turbo up to speed, moving up to the starting line? That's a lot of combustion chamber preheating going on before you've even started your pass.
If a top fuel car had to do that, it wouldn't make it down the track without some serious de-tuning.
I was just thinking. Could an engine tune be run more to the limits on a pass, if you didn't have to spend 7+ seconds stalling on the TC to get the turbo up to speed, moving up to the starting line? That's a lot of combustion chamber preheating going on before you've even started your pass.
If a top fuel car had to do that, it wouldn't make it down the track without some serious de-tuning.
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Dusty Bradford
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We use the same starting line procedure for V6 or V8. 3 step in the top bulb then roll in for final staging. Many guys are now using the bump boxes so they are on the 2 step and trans brake while in the top bulb. This puts them on the trans brake for a lengthy time so you have to be smart about staging. Anyone can race an n/a or blower car. Staging a turbo car competitively in heads up racing is a thinking mans game.
Dusty Bradford
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I've gotten a few emails. I hear they will begin testing soon. I told him you and I would stay in touch once you get some data to see how things are working.
I've been helping them with the tune, converting to the larger injectors. I'm going down there in June to finish the tuning for a big event for the islands. You should see the datalogs so far. You stated you've never seen a turbo car go from idle to launch ready in one second. Want to see it?
You may need to tighten the TC a bit also. They've started launch testing with a target of 6200 rpm on the transbrake. I would like to see it closer to around 5700 rpm for the launch.
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This is interesting! I was looking into purchasing a liquid cooled trans cooler as well to help out with tranny temps.
http://www.exileturbo.com/products/item_details.asp?idProduct=47
Lauch testing with results that that above would definitely make the cars more competitive in a heads up format.
http://www.exileturbo.com/products/item_details.asp?idProduct=47
Lauch testing with results that that above would definitely make the cars more competitive in a heads up format.
Dusty Bradford
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I guess I should clarify....never seen it happen when the converter is efficient. You can have a loose converter or small turbo and it makes a big difference. So this car goes from 1000 rpm to 6200 with launch boost in 1 second? I'd expect launch boost at 6200 to be over 20psi.
Dusty Bradford
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I also forgot your probably using nitrous which changes everything. There are very few heads up classes that allow nitrous along with a turbo in the states so for the sake of this discussion, we are talking about non assisted turbo engines. Anyone can spool a turbo car with nitrous so this trick Alan has been working will not be needed with nitrous. It's more for guys who race on a pro tree with a large turbo, small engine who can't use nitrous.
That's correct. That will be very hard to get all that done in one second without nitrous assist, especially considering that it is going to take over 2 seconds just for the converter to recover from cutting the fluid feed to it.
They have a new turbo on it with a T6 turbine side. Don't remember much more about the turbo.
The MAP was surpassing 200 kPa in the initial stall testing on the transbrake with the nitrous. I had them tame it down a bit, but when we started launch testing they sounded like they wanted more as the driver got used to the car. I guess their new car will handle it.
That is your converter they have in it now, right?
The converter is holding stall at 6250 rpm with 200 kPa MAP, with boost level being controlled. I think the stall could stand to be lower. What do you think? If I remember correctly the duration is around 230s @ .050. I don't expect them to be turning big rpm numbers with this combination. 7000-7500 at the most.
It took 1.3 sec. to reach that rpm and MAP level with a T6 turbine side.
5200 rpm @ 150 MAP within exactly one second.
TC is stalling at 2500 rpm with no boost, no nitrous.
I think I can get the rpm drop on the shift for you too.
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