Dyno results!
#16
Drifting
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Originally Posted by Sameer
38D,
I doubt that as the rest of the cars dynoed fine but will check with them on my next dyno run tomorrow after increasing the CO to 5%. If still runs lean, than I'd just have to go EFI rather than spending more money on the fuel head mod.
I doubt that as the rest of the cars dynoed fine but will check with them on my next dyno run tomorrow after increasing the CO to 5%. If still runs lean, than I'd just have to go EFI rather than spending more money on the fuel head mod.
#17
Race Car
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Guys,
Another thing, if after tomorrow I still run lean, I plan to do the EFI conversion so in the meanwhile isit ok to drive my car regularly off boost till I get my EFI kit together?
Another thing, if after tomorrow I still run lean, I plan to do the EFI conversion so in the meanwhile isit ok to drive my car regularly off boost till I get my EFI kit together?
#20
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I've never quite understood why you should care about the CO%. Seems like you'd just stick it on the dyno, and adjust the fuel setting to where you need it. Gradually move up the RPM range, when you see the AFR go high, shut it down, adjust the fuel load, and then dyno again, do this over and over until you get it to a manageable level.
But like I said, I don't know why CO% matters. I've never understood that. (but I'm not an expert). I guess I've just never heard any other cars being tuned for CO%, not that they haven't been tuned that way, but I haven't heard about it I don't think.
That's just my thought. Stick it back on the dyno, once you confirm that their AFR gauge is working properly, and make small incremental adjustments with the fuel head screw until you hit a target AFR.
I seriously doubt you are out of fuel adjustment. Maybe on the Andial you are, but probably not at the fuel head itself.
Brian
But like I said, I don't know why CO% matters. I've never understood that. (but I'm not an expert). I guess I've just never heard any other cars being tuned for CO%, not that they haven't been tuned that way, but I haven't heard about it I don't think.
That's just my thought. Stick it back on the dyno, once you confirm that their AFR gauge is working properly, and make small incremental adjustments with the fuel head screw until you hit a target AFR.
I seriously doubt you are out of fuel adjustment. Maybe on the Andial you are, but probably not at the fuel head itself.
Brian
#21
Race Car
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Brian,
If I increase the CO would'nt that fatten the fuel mixture helping it to achieve better a/f ratio? Surely I would get a better a/f ratio with 5% CO than with 3.7% CO which I'm currently running. Yes I might be running a little too rich at the low end but at least I will get a better a/f ratio minimising running lean?
If I increase the CO would'nt that fatten the fuel mixture helping it to achieve better a/f ratio? Surely I would get a better a/f ratio with 5% CO than with 3.7% CO which I'm currently running. Yes I might be running a little too rich at the low end but at least I will get a better a/f ratio minimising running lean?
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Sure it'll fatten it more than likely. But all I'm saying is why do you care about the CO% (unless of course you have to pass certain emissions requirements).
You should be more concerned with AFR that CO, at least I would think. Sure, one is an indication of the other, a 5% CO isn't going to tell you what your AFR will end up being. All you'll know is that, yes, more than likely, it is getting more fuel.
Brian
You should be more concerned with AFR that CO, at least I would think. Sure, one is an indication of the other, a 5% CO isn't going to tell you what your AFR will end up being. All you'll know is that, yes, more than likely, it is getting more fuel.
Brian
#23
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Brian,
Sorry, I get what your saying which is basically to work the other way round. Adjust the CO according to the a/f ratio.
Thanks, will do so tomorrow and keep you'll posted.
Sorry, I get what your saying which is basically to work the other way round. Adjust the CO according to the a/f ratio.
Thanks, will do so tomorrow and keep you'll posted.
#24
Three Wheelin'
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Originally Posted by Sameer
How can my fuel distributor with Andial FEC not be enough to support the mods above?
Stephen is just finishing my EFI conversion with a K27HF2, so I'll let you know what the torque curve looks like with that setup. Should be about what you are looking for (hopefully 500 or so at the wheels...)
On your question of cost of the EFI conversion (from another thread), take your guestimate and double it. It's just damned expensive, no two ways about it.
-dc
#25
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Sameer - adjusting the CO will not get you close to the AFR you need to run. It has a very small affect on overall AFR and is used to fine tune a WUR that is working correctly or is set up correctly. For example, I could run 12.5:1 AFR and set the CO to 0%.
CIS AFR is dependant on the WUR allowing fuel pressure to act on the fuel head - lower WUR pressure, the lower pressure it uses on the fuel head, the more fuel is allowed to pass through the fuel head. Higher pressures from the WUR act to build pressure against fuel head and decrease the fuel flow. So, messing with the CO will have little or no result in an AFR that is that far off.
Quite frankly, I am surprised your motor is still running if you are running + 14:1 AFR on boost. I guess its possible the dyno probe is bad, but don't count on it.
As for the larger turbo, since the metering plate (before the turbo) moves to allow the metering pin to measure the fuel flow (and the twisting intake tubes of the CIS don't allow that much air to move), I seriously doubt the turbo is a problem. In addition, I ran three different sizes of turbos (two bigger and better than the K29) on my CIS without this problem.
Why isn't the Andial working correctly? Check it out before you go back to the dyno. It should give you some fuel, but again, if the WUR is working correctly, you WILL NOT GET FUEL. Again, the very first place to start is to measure the fuel pressures between the WUR and fuel head, cold and warm. I would bet they are very high.
One last thing - it is my opinion that if your CIS is properly tuned, you would be hard pressed to beat that system with EFI, all things being equal.
CIS AFR is dependant on the WUR allowing fuel pressure to act on the fuel head - lower WUR pressure, the lower pressure it uses on the fuel head, the more fuel is allowed to pass through the fuel head. Higher pressures from the WUR act to build pressure against fuel head and decrease the fuel flow. So, messing with the CO will have little or no result in an AFR that is that far off.
Quite frankly, I am surprised your motor is still running if you are running + 14:1 AFR on boost. I guess its possible the dyno probe is bad, but don't count on it.
As for the larger turbo, since the metering plate (before the turbo) moves to allow the metering pin to measure the fuel flow (and the twisting intake tubes of the CIS don't allow that much air to move), I seriously doubt the turbo is a problem. In addition, I ran three different sizes of turbos (two bigger and better than the K29) on my CIS without this problem.
Why isn't the Andial working correctly? Check it out before you go back to the dyno. It should give you some fuel, but again, if the WUR is working correctly, you WILL NOT GET FUEL. Again, the very first place to start is to measure the fuel pressures between the WUR and fuel head, cold and warm. I would bet they are very high.
One last thing - it is my opinion that if your CIS is properly tuned, you would be hard pressed to beat that system with EFI, all things being equal.
#28
Drifting
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#29
Burning Brakes
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If you wanna spend the money then go EFi id say- Sammer you have internal mods done already on your engine- this is not the limiting factor to more power! CIS is so if YOU went Efi then you could be gaining more power than most people with stock engines... in some ways you are wasting all that $$$ spent on the internals
Efi is expensive but maybe this might change in a few months when I have done mine- I am not saying anything yet because I havent got mine up and running yet...
Oh Sandman my man - didnt Don blow his engine because he didnt have a a/f guage at the time he was running super lean! I think if you have the onboard guages you need boost, a/f, & poss EGT and play it safe all the time I dont see why you could stay out of this pitfall...
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Efi is expensive but maybe this might change in a few months when I have done mine- I am not saying anything yet because I havent got mine up and running yet...
Oh Sandman my man - didnt Don blow his engine because he didnt have a a/f guage at the time he was running super lean! I think if you have the onboard guages you need boost, a/f, & poss EGT and play it safe all the time I dont see why you could stay out of this pitfall...
#30
Nordschleife Master
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Derick, 500hp to the wheels with a standard 3.4l engine build and 964 cams with standard exhaust might happen at 1.2+bar of boost. From my experience all that you'll see will be in the range of 440-460hp at 1bar of boost with that type of build. 500rwhp and over generally requires significant air flow improvements (intake, cams, heads, exhaust, and a good turbo).