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Discussion Starter #1
Hi all, I have a 02 lexus is300 with 2jzgte swapped engine. I recently installed a single turbo set up (6262)
From driftmotion. Car runs fine but it shows on afr gauge its idle is at 17-18
Normal driving 15-17
WOT 12.2-13 so I'm not sure how to go about it. I just pulled a plug out and it looked what white. I'm assuming that is a sign of lean also? The car use to have stock twin and would back fire. It don't anymore . Also when I had the stock twins the afr gauge didn't work so I'm not sure where I was at with it at the momment. I currently replaced my fuel filter. Oh and it has a walbro 255 fuel pump. Stock 440cc injectors. Any help is appreciated. Thanks
 

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How much boost are you running? Whats your EMU? Stock fuel? From twin to single the flow changes so your map may need adjusting depending on how much you are running on the bigger turbo.
 

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Discussion Starter #3
I'm on stock ecu. Boost is set at 13.6
I was told I could run low boost on stock ecu. I actually seen it done.
Fuel is stock with exception of walbro fuel pump 255
 

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Discussion Starter #5
Both, it's running gte ecu for the engine, and wired in to the tack and all the bs to work inside the car
 

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Cherisher
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It's been a long time but 13.6 kinda sounds like a lot on stock ECU's and injectors. Sounds to me like you're maxed and can't get enough fuel in. Bottlenecked by the capabilities of the electronics... ?
 

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Discussion Starter #7
It has the same afr on 10psi. I doubt that is the case. I'm thinking I may have bad injector or injectors. I'm 100 percent sure it ran rich when I originally bought the car.
At that time the afr gauge was not showing because or the faulty 02sensor that is when it was on stock twins boosting at 18psi. Turbos were leaking hense why I chose to install single instead of a rebuild. Its just hard to believe that a single turbo would make any difference in afr. Boost is boost dont matter where it's coming from. Aaron at driftmotion has helped out alot on the build so shout out to him! Got some before after pics . So I think if I i get the safc2 that may be just what I need to fix this issue
 

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Cherisher
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Again, sounds like a lot of boost for stock and the borrowed numbers are expired. I'm leaning towards maxed injectors without enough tune.

Same as, you can run 450HP on stock pistons but there is an expiration date.
 

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Again, sounds like a lot of boost for stock and the borrowed numbers are expired. I'm leaning towards maxed injectors without enough tune.

Same as, you can run 450HP on stock pistons but there is an expiration date.
Pretty much...but yeah.

I was told I could run low boost on stock ecu.
Low boost on a bigger turbo is a smaller number. Low boost on a tiny turbo is a bigger number. Because its not about the pressure across the compressors outlet but about the volume of air blowing out.

Its just hard to believe that a single turbo would make any difference in afr. Boost is boost dont matter where it's coming from.
Just to be clear, are you saying that a gt28 at 13 psi moves the same volume of air as a 6262 at 13 psi?
 

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Discussion Starter #10
I'm not saying that a gt28 moves same amount of air as a 6262.
I'm saying that it dont make sense that my injectors are being maxed out with that amount of psi.
Chech this video on YouTube
Motion auto TV. And the whp numbers. He used a garret gt35 which by no means is a small turbo stock injectors stock ecu. No problems with AFR like my car. So I dont think it's the turbo set up that is leaning my car out.

 

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Discussion Starter #11
I mean I'm pretty sure It could be fixed with a tune. I just thought maybe there's an easy fix before I go spending money on a standalone or a piggy back. But I was told piggy backs dont work well with gte vvti
 

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Like everyone else said: boost does not equal boost. A high volume turbo at low boost can flow much more than a smaller turbo at high boost.

That said, Toyota’s of this vintage usually run pig rich under load. Are you certain the AFR are correct? Like have you calibrated the wideband sensor? You can have the injectors tested pretty easy. If all that checks out, I’d say you’ve tapped out the stock fuel capabilities.

Standalone ecu is the next logical step here, anyways. It snowballs fast because you’ll want a new fuel rail, injectors, fpr, lines, etc.
 

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Maybe try running 5 or 6 psi and look at AFRs? Its a quick and easy check. Like i said....low boost on different turbos are different numbers and the 440s max out quickly once you really start moving volume. Idk the 6262 enough to venture a guess at what low boostf might be though.

Sent from my SAMSUNG-SM-G930A using Tapatalk
 

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Discussion Starter #14
Like everyone else said: boost does not equal boost. A high volume turbo at low boost can flow much more than a smaller turbo at high boost.

That said, Toyota’s of this vintage usually run pig rich under load. Are you certain the AFR are correct? Like have you calibrated the wideband sensor? You can have the injectors tested pretty easy. If all that checks out, I’d say you’ve tapped out the stock fuel capabilities.

Standalone ecu is the next logical step here, anyways. It snowballs fast because you’ll want a new fuel rail, injectors, fpr, lines, etc.
Thanks for your help! I did calibrate the wideband sensor multiple times. It shows the same thing. I do know the engine normally runs rich the 2jzgte. In wot it shows 12.2 so I guess that's safe? Its only on idle and normal driving it's like 17.
 

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Discussion Starter #15
Maybe try running 5 or 6 psi and look at AFRs? Its a quick and easy check. Like i said....low boost on different turbos are different numbers and the 440s max out quickly once you really start moving volume. Idk the 6262 enough to venture a guess at what low boostf might be though.

Sent from my SAMSUNG-SM-G930A using Tapatalk
I can't run that low of boost my waste gate spring is at 10lbs . I did mention it just idles lean and normal driving but on wot it goes down to 12.2
Thanks for your input:)
 

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It’s still weird it idles that lean. Guess it won’t hurt at idle since there is no load, but I would be concerned with 17 afr cruising. Too lean IMO. I’d watch it closely during initial-hi throttle to make sure it’s fattening up the AFR quickly.

Where is the MAF sensor plumbed in at? Do you have a recirced or atmospheric BOV?
 

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Discussion Starter #17
It’s still weird it idles that lean. Guess it won’t hurt at idle since there is no load, but I would be concerned with 17 afr cruising. Too lean IMO. I’d watch it closely during initial-hi throttle to make sure it’s fattening up the AFR quickly.

Where is the MAF sensor plumbed in at? Do you have a recirced or atmospheric BOV?
I know it's weird why it idles lean, especially being completely stock.
I have an hks bov to atmosphere.

The Maf is where it should be. Its hidden on the other side of the 4ich intake pipe. That is totally custom got a welded flange for it to work.

Now here's the kicker. Normally I guess your supposed to use an OEM size intake pipe for that maf which is no bigger then 3 inch. I hated the little three inch pipe so what I did was I have a three inch pipe inside the 4 inch intake pipe. If That makes sense! So the maf basically breathes thrue a 3 inch intake pipe inside a 4 inch pipe that goes straight to the turbo.

I did try to run the car with 4 inch pipe with maf flow installed but it just stalls.
 

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What you’re saying kinda makes sense - pic is worth 1000 words - but I wonder if that 3” pipe in a 4” pipe MAF voodoo is causing problems? If it was backfiring on stock twins and it’s not backfiring on a single turbo then it’s running leaner than before. Pretty straightforward process there, am I wrong? To determine why, is the hard part. Any way you could put your old twin turbo intake on the new 6262? May take a reducer coupling but would eliminate a variable.
 

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Discussion Starter #19
Only way for me to put the old twin turbo intake back on is to get a new one with a welded flange. I hacked the flange of of that one (the 3 inch pipe) and welded on 4 incher. I guess I could just get a new 3 inch pipe with maf flange from driftmotion. And see if that helps. I'm seriously going to try that. Thanks for your help!
 

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Only way for me to put the old twin turbo intake back on is to get a new one with a welded flange. I hacked the flange of of that one (the 3 inch pipe) and welded on 4 incher. I guess I could just get a new 3 inch pipe with maf flange from driftmotion. And see if that helps. I'm seriously going to try that. Thanks for your help!
Your MAF being in a 4 inch pipe. You need to re-calibrate the values. Putting a 3 inch inside a bigger pipe will not work.
The MAF calculates the voltages according to temp of wires in the sensor. You have more air going in. So the voltages are off. Causing not enough fuel. If I remember. You could just use the MAP sensor only with a stand alone.
 
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