well i've been having trouble w/ my car eating coolant...so i went to the dyno to see the power results

mods are:

greddy airnix
hkts ss bov
greddy FMIC
bonez downpipe
high flow cat
greddy power extreme
magnecore 10mm wires
93 octane@12psi

i dynoed 294rwhp, 266.9 peak torque with 14:1 a/f ratio and 97.4 peak injector duty, .98kg/cm2 peak boost

now, this is wayy too lean and the boost is spiking too much

do you think my turbos are baked and this is eating my coolant? i have another set i am thinking of swapping on

obviously i need a supra pump and new fuel maps

are these numbers good?

 

bump

 

Those are good numbers, but not very realistic. Your motor wont be around much longer running those A/F ratios.
Why do you think your car is eating coolant?

Jason

 

i'd be worried about the injector duty cycle too!

 

i keep having to add coolant only when i let it sit for a while.....

i drove from macon to atlanta (80miles or so) and added a cup of coolant...

sometimes it needs more, it's erratic

maybe the turbos are shot and they're eating cooalnt

 

there is no real way that the turbos can eat coolant. the coolant passages don't have any seals that would leak. only way would be if they were cracked.
unfortunately, you probably either have a leak or an o-ring problem

 

that pic leads me to believe that 14.7 is the ideal a/f ratio

is that correct?

 

14.7 is stoich for burning gasoline most efficiently. It is way too lean for WOT though. More than 11.5 A/F on the dyno is pushing it on 93 octane.

 

ahh, i see...so 14.7 is good for < WOT, but for WOT i need to shoot for 11.5

 

Yeah, thats a ballpark figure that can be pushed either way based on timing and pocketbook.

There is something a little odd about your pull though. At 97% duty cycle you theoretically should not be at 14:1 making 300 rwhp. That much duty cycle at that power level should put you in the 10s AF wise.

Do you have a pic of the sheet?

 

double post

 

If coolant isn't leaking out anywhere it is being consumed by the motor due to a broken coolant o-ring. This means its time to rebuild the motor. Also, make sure you are using a wide band 02 sensor on the dyno.

 

Triple post

 

Few things have me concerned....Your AFR is way too lean....i wouldnt go wot until you could add some fuel via some tuning and some 1300cc inj.
Secondly, the rwhp you are making is not indicitive of the trap you posted. You should be around 110 with that much rwhp. Something is up with your set up. I would take it to a qualified rotary mechanic ASAP. IF it was my car i wouldnt even drive it until i got some answers.

 

I dont know man...i made 300rwhp with my old similar setup and i was seeing 90s inj duty cycle @ 12 psi and had an 11.2 afr.
Once u make 300rwhp or more it is time to upgrade the inj. I know some will disagree but thats my experience with the stock motor/turboes.

 

i'm just going to upgrade the fuel pump, that should help

and it's not necessarily my coolant o-ring, it could be a lot of other things

 

The pump will hold better pressure...won't add more fuel. Your inj. duty cycle is WAY high for that lean, did Arthur allow you to run WOT with that A:F(assuming you went to th Dynolab.

Wouldn't say a lot...

Sounds like O-ring denial.

 

14.1 afr is way way to lean for a turbocharged car... On a naturally aspirated engine you want to see about 14:1 at wot throughout the run... but on a car with a turbo your air fuel should start at around 14 and as your boost comes on your air fuel should drop significantly and hold around 10:5- 11:2... some people run leaner but i like the margin of safety for that day the car decides to run lean

 

i am running tim's maps on the PFC, he has an upgraded fuel pump, so that's why i ask...

i went to batlground engineering, they're closer to me, and they didn't like the a/f ratios at all, i only did one pull w/ the wideband

 

get bigger inj;s too.

 

why don't you just get a pressure tester and test the coolant system? or a compression test. those'll tell ya a bunch.

 

and i'm not in o-ring denial, i ordered the rebuild kit

 

If you see 97% duty cycle and with your HP figure, you can't be running at 14.1 a/f. Most likely to be about 10.5 a/f or lower. If you are reading from your RP a/f gauge, you should not worry about it. That one is not accurate because it's not a wideband

Chuck Huang

 

i was hooked to the dyno's wideband, thats just a pic from rikki's car i found

i was making 14:1

 

That's very strange because the injector duty cycle and your HP do not add up right.

stock injectors running at 97% can support about 350-360 HP at the wheel at the 11.5 a/f.

Maybe your fuel pump is bad, fuel filter is clogged, the duty cycle that you are getting is not accurate or the wideband is not accurate.

You should post your dynosheet here. If you are really running at 14.1 a/f, your will have a very bad break up at high rpm and you can see it from the dynosheet.

Chuck Huang