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Learning about my car (pulley/intake/tune)

350 Views 18 Replies 5 Participants Last post by  Catmonkey
I've never owned a forced induction car before so I've got some learning to do. I'm also not really a "car guy" by way of experience working on cars. So, with that being said, how can I tell how much boost I am running? When looking at the boost gauge in the menu, at WOT, it creeps up pretty high. Like, I've seen it at around 18 PSI. I know there is an aux tensioner pulley installed, but is there a way I can tell if any of my pulleys are aftermarket? I know I've got a Lund tune installed on the car but Idk if that would increase boost on it's own.
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Post a pic of your engine bay.
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Post a pic of your engine bay.
Sorry about that. Here it is.
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Pulley/intake/tune mod. If you are making 18 lbs of boost, you most likely have a smaller upper pulley, which is why you also have an aux idler (more belt wrap). Do you have a dyno printout by chance? I assume your air/fuel ratio is good with a Lund tune, but you can’t be totally positive unless you get eyes on and an error could be a costly mistake.
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Sorry about that. Here it is. View attachment 277158
Moved your post here to our performance mods section. Be sure to empty your passenger side oil catch can periodically.
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You have aftermarket CAI by JLT, Cold Air Intake and filter, you also have Oil Separators (catcher cans on both sides) it 'appears' to have a smaller drive pully on the supercharger with the auxiliary tensioner.
This would go with the LUND Tune (IF THERE ACTUALY IS ONE, DO YOU ABSOLUTELY KNOW FOR SURE ! )
Do you have the Tuning device that should have been with the car?
If would like to know contact LUND for the specifics, he may have a record of it possibly by the VIn or previous owners name.
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Tim beat me to a response!
RE; the tune
I would NOT drive it hard or get into the BOOST until you know the TUNE is CORRECT... You would be putting the engine in jeopardy by doing so... this can be VERY expensive!!!!

AGAIN... I would NOT push the car into BOOST without knowing for certain the 'Tune' is there to assure the thing does not go LEAN...
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Pulley/intake/tune mod. If you are making 18 lbs of boost, you most likely have a smaller upper pulley, which is why you also have an aux idler (more belt wrap). Do you have a dyno printout by chance? I assume your air/fuel ratio is good with a Lund tune, but you can’t be totally positive unless you get eyes on and an error could be a costly mistake.
Tim beat me to a response!
RE; the tune
I would NOT drive it hard or get into the BOOST until you know the TUNE is CORRECT... You would be putting the engine in jeopardy by doing so... this can be VERY expensive!!!!

AGAIN... I would NOT push the car into BOOST without knowing for certain the 'Tune' is there to assure the thing does not go LEAN...
Thank you both for your posts. I have been in contact with the original owner, as well as Lund. He is going to mail me the nGauge tuner that was used to apply the tune to the vehicle. I figured that it was a smaller upper pulley but was not sure because it looks just like the stock one IMO. I know that the car has the CAI, and the aux tensioner pulley....as well as the Lund tune and a catless midpipe and corsa extreme catback (or is it axle back on this car?). Beyond this I am not sure. I would imagine that the tune is good to go since Lund has it on record that way.
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.......I know I've got a Lund tune installed on the car but Idk if that would increase boost on it's own.
The Tune would not increase the boost.
The undersized pully does that by spinning the supercharger faster. Pushing more air O2 into the cylinders.
The tune will tell the controls at what rate an time the injectors allow fuel into the engine among other things, timing, temperatures, most important is the air/fuel ratio... it goes lean your engine would tend to open window(s) in the side of the block!
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The Tune would not increase the boost.
The undersized pully does that by spinning the supercharger faster. Pushing more air O2 into the cylinders.
The tune will tell the controls at what rate an time the injectors allow fuel into the engine among other things, timing, temperatures, most important is the air/fuel ratio... it goes lean your engine would tend to open window(s) in the side of the block!
Thanks. Without having the tuner, is there any benefit to me requesting any specific information from Lund that might help me?
I would be curious as to who installed the parts and did they Dyno the car...
Lund most likely sent the tune remotely.

It may have never even been put on a Dyno.
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I would be curious as to who installed the parts and did they Dyno the car...
Lund most likely sent the tune remotely.

It may have never even been put on a Dyno.
That's probably a fair assumption. The previous owner is currently out of town attending funeral arrangements for a relative so I'm trying to leave him alone for the time being.
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Before a tune is loaded, the stock calibration gets saved to the flash device, so it is possible to return the calibration to stock. That would be the concern, because some guys sell what ever aftermarket parts they installed to maximize the selling price. Since those parts are still on the car, and he has the nGauge, there would have not be a reason to do that. But if you can contact the seller and verify that the Lund tune is still in the PCM, I would do that. There's virtually no way to tell other than data log the car and look at the data.
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Before a tune is loaded, the stock calibration gets saved to the flash device, so it is possible to return the calibration to stock. That would be the concern, because some guys sell what ever aftermarket parts they installed to maximize the selling price. Since those parts are still on the car, and he has the nGauge, there would have not be a reason to do that. But if you can contact the seller and verify that the Lund tune is still in the PCM, I would do that. There's virtually no way to tell other than data log the car and look at the data.
John
That was my concern. When buying a previously owned vehicle and seeing that Mods have been made with nothing more than 'someone saying' it was tuned correctly would be a red flag to me. I would have to have Proof before I would take the car out and drive it hard, into Boost... you are taking chances that the thing could run lean... too many have had an engine trashed for this reason! It shouldn't take too much to make contact with the PO and Lund to assure all is good. And even at that the only way to be certain would be to Data Log and be certain of what you have.
It can be a very expensive error to take a chance just on some body's word.
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John
That was my concern. When buying a previously owned vehicle and seeing that Mods have been made with nothing more than 'someone saying' it was tuned correctly would be a red flag to me. I would have to have Proof before I would take the car out and drive it hard, into Boost... you are taking chances that the thing could run lean... too many have had an engine trashed for this reason! It shouldn't take too much to make contact with the PO and Lund to assure all is good. And even at that the only way to be certain would be to Data Log and be certain of what you have.
It can be a very expensive error to take a chance just on some body's word.
Yeah, which is why I made contact with both Lund and the previous owner. I feel pretty confident the car has a legitimate tune on it but I still plan on getting the tuner from the PO.
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Yeah, which is why I made contact with both Lund and the previous owner. I feel pretty confident the car has a legitimate tune on it but I still plan on getting the tuner from the PO.
A wise and prudent thing to do.
BUT.... even with a 98% sure it has been done... that 2% can cost you tens of thousands.
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After market throttle body too? It looks shiny in the picture instead of a flat aluminum look. I can't see if it has a stop on top of it to identify the mfr.
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I just contacted one of the previous owners and he sent me this list of mods on the car!
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With a super big air, it has to have a tune or it wouldn't even run.
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