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High fuel pressure on boost

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Innovate and OBX carries WB heat sinks. You may be able to find them cheaper elsewhere. If WB O2 sensor is close to Turbo, you may be over heating it. Innovates is $89.95. OBX is $49.95. Read the Innovate tech information though. 

 

http://www.innovatemotorsports.com/xcart/product.php?productid=16148

 

http://www.ebay.ca/itm/OBX-Racing-Sports-O2-Sensor-Heat-Sink-Bung-Extender-for-Wideband-Controllers-NEW-/191165135135

 

$(KGrHqYOKi!E5M3U8tTDBOc7+V0W6g~~60_35.J

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Edit: ECU and Lambda  AFR Meter could very well be using separate O2 sensors. WB sensors did not start to be commonly used until 2000, when OBD-2 spece was brought in. Previous to that NB was used in most cars. 

 

However, most modern AFR gauges are all WB now. Some have auxiliary outputs for an extra WB output and/or an emulated NB output.

 

I believe that the OP bought a JWT kit that includes a modified 88 -89 Z31 ECU core. Part # E280U-TMU4F . These would use a  Narrow Band O2 sensor. I don't think they can be converted to WB. Is this correct? 

 

 

Edited by Chickenman

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Knowing exactly what fuel you are running is extremely important with AFR meters. Less so with Lambda meters. They are NOT the same thing.

 

 

WB O2 sensors output Lambda values. Stoich is always 1.0 Lambda  However, depending on fuel, a Lambda value of 1.0 can vary greatly when converted to AFR.  AFR meters convert the Lambda value  to a table for a specific fuel. Usually pump gas. Some has switchable tables for E15, E85 Diesel etc. There lies the problem. Even pump gas varies quite a lot in formulation. A Lambda value of 1.0 with Shell pump fuel may output a different AFR reading than Chevron pump gas.  

 

Race Gas does not have the same AFR values as Pump gas at Stoich. That of course affects values at WOT when mixture is richer.

 

The following article explains the difference between Lamda values and AFR. Be sure to read the complete article. It's very interesting, and shows why AFR meters should be taken ONLY as a guide and not an absolute. 

 

http://www.ultra-gauge.com/customer_support/knowledgebase.php?article=29 

 

post-44147-0-66705800-1486417580_thumb.jpg

 

Hope I'm not confusing things to much... but accurate data and accurate data interpretation  is all important. Bottom line. Always give the engine what it wants. Instruments can lie... the engine won't. 

Edited by Chickenman

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The above points to a reason why a good stand-alone can be an advantage for the weekend warrior over a converted factory ECU. Particularily an older style such as the JWT. The ability to run multiple fuel and spark Maps is huge. You can tune your car to run at reduced boost and optimized fuel tables for 91 pump gas. And then flick a switch and have it optimized for Race Fuel or even E85. 

 

Might be something to consider down the road. 

Edited by Chickenman

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Obvious question, but is the Race Gas Lead free? If not O2 sensor is likely contaminated. What race gas is it. Is it E85 by chance? 

 

How close is the O2 sensor to the Turbo? You may need a Heat Sink for it. WB sensors are more sensitive to excess heat than NB sensors. I'll try and find a link.

 

Another question, and we need this one answered please. What was the exact pressure that the FPR was set to at idle and was the vaccuum reference line to the FPR disconnected or connected when you set the Fuel pressure? 

 

Curious. If you have a Lambda gauge and the minimum reading is 1.0. That equals 14.7 AFR with Gasoline. So how are you measuring any numbers less than that?

Fuel is 91 with Torco race additive.  O2 is 10 " away, LC1 is 30" away.  

The gauge is not in lamda, its in AFR.  Min is 10 max is 20 AFR. 

Fuel pressure is set correctly as stated before, 30 psi with vacuum 36 psi without.

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Chicken man is onto something although one would assume your AFR gauge and your ECU are reading off the same o2 sensor.

 

You have to answer the questions man, questions that have been fairly repeated at this point.

 

I think I'm out here. 

What am I not answering?  Sound like all of this is upsetting you.  I have a life outside of this forum so give me a little time to reply to all the questions.

Edited by Timecode

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Knowing exactly what fuel you are running is extremely important with AFR meters. Less so with Lambda meters. They are NOT the same thing.

 

 

WB O2 sensors output Lambda values. Stoich is always 1.0 Lambda  However, depending on fuel, a Lambda value of 1.0 can vary greatly when converted to AFR.  AFR meters convert the Lambda value  to a table for a specific fuel. Usually pump gas. Some has switchable tables for E15, E85 Diesel etc. There lies the problem. Even pump gas varies quite a lot in formulation. A Lambda value of 1.0 with Shell pump fuel may output a different AFR reading than Chevron pump gas.  

 

Race Gas does not have the same AFR values as Pump gas at Stoich. That of course affects values at WOT when mixture is richer.

 

The following article explains the difference between Lamda values and AFR. Be sure to read the complete article. It's very interesting, and shows why AFR meters should be taken ONLY as a guide and not an absolute. 

 

http://www.ultra-gauge.com/customer_support/knowledgebase.php?article=29 

 

attachicon.gifUltra Gauge AFR 001.jpg

 

Hope I'm not confusing things to much... but accurate data and accurate data interpretation  is all important. Bottom line. Always give the engine what it wants. Instruments can lie... the engine won't. 

Chickenman, thanks for your patience and perseverance. When I found out that race gas did read richer, I thought that was it but, strangely, I notice the same AFR's with 91 pump as I do with my race mix. No major change that I can see.

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Fuel is 91 with Torco race additive.  O2 is 10 " away, LC1 is 30" away.  

The gauge is not in lamda, its in AFR.  Min is 10 max is 20 AFR. 

Fuel pressure is set correctly as stated before, 30 psi with vacuum 36 psi without.

 

Got it now. But 4 to 5 psi varience in Fuel pressure really doesn't affect AFR all that much.

 

Edit: Octane additives also change AFR values. 

 

Could still be an O2 sensor going south due to contamination. Particularily if you are using Octane Boosters on a regular basis. .

 

Personally I don't trust Torco products. If an Octane Booster contains MMT  even small amounts, then the O2 sensor contaminates the O2 sensor. Apparently Torco contains a fairly large amount of MMT and that is not good news for O2 longevity. 

 

Google: " Does Torco Octane Booster contain MMT ". Lots of people seem to be having issues with it and O2 sensors. Contrary to Torco's advertisement claims that it won't harm sensors and Ctalytic convertors..... take it with a grain of salt... but something to consider. MMT is one of the most effective Octane Boosters... but it has drawbacks.

 

MMT was banned from pump gas in Canada around 2006 and I believe earlier in the USA. 

 

Pull the O2 sensor. If it looks Reddish Brown or Orange Brown, that is likely MMT deposits and WB O2 sensors do not like it. 

 

https://www.svtperformance.com/forums/threads/anyoe-use-the-torco-fuel-additive-in-place-of-race-gas.647110/page-2#post-9016727

 

4096576864_5114a22c70_o.jpg

Edited by Chickenman

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Since you JWT ECU does not have any real time feedback control...  the only real thing affected by any O2 contamination is likely your O2 sensor for your AFR meter. If the engine is happy... don't screw it up with possible erroneous Instrument readings.

 

Would still like to see pictures of those plugs... 

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Yeah, Reddish Brown on the plugs is a sure sign of MMT.  Sounds like your tune is safe rich though. I assume you're running Water Meth?  

 

Some of the Big Boost Turbo guys run an Auxilary tank that is just used for real Race Fuel when they really crank the boost. A small 5 to 8 gallon fuel cell for Track Days or Autocross. We can't get E85 in BC. 

 

E85 may be the way to go eventually for you, since you live in Cali. It's readily available there isn't it?

 

That would require a different ECU ( and injectors ) , but a MS 2 Pro assembled is only $445 from DIYAUTOTUNE. And you could sell the JWT ECU for good money. Would give you a lot more Tuning Options.

 

https://www.diyautotune.com/product/megasquirt-ii-ems-system-smd-pcb3-57-assembled-ecu/

 

A MS 3 Assembled is $659. Thta adds a lot more outputs and allows you to run COP ignition and full sequentail fuel injection $659 at DIY:

 

https://www.diyautotune.com/shop/megasquirt-assembled/megasquirt-3-megasquirt-assembled/

 

E85 would be the way to go IMHO....

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the JWT 500 tune is pig rich unless you have had a custom burn.

JeffP was blowing smoke on his at 25psi. It took a run to JWT and Clark reworking the map to get it leaned out properly.

 

My bet is your map is the issue. It sounds just like all the other ones I've seen... likely I would doubt your AFR gauge, and verify that. Jeff's was in the 10:1 or lower area, and if you don't see smoke you aren't below 10:1... 

 

My 2 cents...

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the JWT 500 tune is pig rich unless you have had a custom burn.

JeffP was blowing smoke on his at 25psi. It took a run to JWT and Clark reworking the map to get it leaned out properly.

 

My bet is your map is the issue. It sounds just like all the other ones I've seen... likely I would doubt your AFR gauge, and verify that. Jeff's was in the 10:1 or lower area, and if you don't see smoke you aren't below 10:1... 

 

My 2 cents...

 

Yeah... I was kinda getting to that in a round about way. I just don't see the point in using a non-programmable ECU these days, particularly in a Turbo car with that many Mods.  E85 and a programmable stand alone are in OP future me thinks...

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It is the same car. That was a intermitint tps fauilure causing the flames. Standalone is another can of worms that I can't tackle right now. I'll just keep the boost down and enjoy it. It's a hoot at 15#'s, so I'm good with this setup for now. Later down the road I'll get standalone or a new flash from JWT.

 

Interstingly, my evo x runs in the 9-10 afr from the factory with no smoke as well. Thanks for all the help everyone.

Edited by Timecode

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