Is my buddy being dumb?
02-21-2010, 05:14 PM
#43
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Join Date: Dec 2008
Location: Colorado
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Holy exploding thread Batman.
Seriously, this whole thread can be sumed up as follows:
Can we just run insanely low boost without any big fueling mods. This guys says so.
No. See Stickies.
I bet it would work.
You cant run any boost without something!!!!!!!!!!!!!!!!!!!!!!!!! Die!!!!!!!!!!!!!!!!!
OK OK.
Die!!!!!!!!!!!!!!!!!!!!!! *&^(*&%^%$%#$%#!!!!!!!!!!!!!!!!!!!
And a few people in here attempting to punch above their weight when it comes to 'what will happen'. I do this too so I hardly look down on it, I just want to point it out.
On a mass-air based management system, you dont 'only get enough fual for 0 vacume'.
You get fuel based on the airflow as read by the MAF/AFM sensor which could care less what pressure is between the turbo and intake manifold. The additional flow through the AFM causes the ECU to try to deliver more fuel.
So while it is a horrendously bad idea to just run 5 psig with no fueling mods, the car will attempt to maintain the proper AFRs assuming it is an AFM equiped vehicle.
Frankly if the fuel pressure was set higher and a bigger pump put in such that the car simply ran rich in WOT situations and the base timing was set way down, it would likely survive a long time. It would have crap power and be a joke compared to what it would be with decent management. But it would likely be OK.
Seriously, this whole thread can be sumed up as follows:
Can we just run insanely low boost without any big fueling mods. This guys says so.
No. See Stickies.
I bet it would work.
You cant run any boost without something!!!!!!!!!!!!!!!!!!!!!!!!! Die!!!!!!!!!!!!!!!!!
OK OK.
Die!!!!!!!!!!!!!!!!!!!!!! *&^(*&%^%$%#$%#!!!!!!!!!!!!!!!!!!!
And a few people in here attempting to punch above their weight when it comes to 'what will happen'. I do this too so I hardly look down on it, I just want to point it out.
On a mass-air based management system, you dont 'only get enough fual for 0 vacume'.
You get fuel based on the airflow as read by the MAF/AFM sensor which could care less what pressure is between the turbo and intake manifold. The additional flow through the AFM causes the ECU to try to deliver more fuel.
So while it is a horrendously bad idea to just run 5 psig with no fueling mods, the car will attempt to maintain the proper AFRs assuming it is an AFM equiped vehicle.
Frankly if the fuel pressure was set higher and a bigger pump put in such that the car simply ran rich in WOT situations and the base timing was set way down, it would likely survive a long time. It would have crap power and be a joke compared to what it would be with decent management. But it would likely be OK.
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02-21-2010, 05:46 PM
#44
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Holy exploding thread Batman.
You get fuel based on the airflow as read by the MAF/AFM sensor which could care less what pressure is between the turbo and intake manifold. The additional flow through the AFM causes the ECU to try to deliver more fuel.
So while it is a horrendously bad idea to just run 5 psig with no fueling mods, the car will attempt to maintain the proper AFRs assuming it is an AFM equiped vehicle.
Frankly if the fuel pressure was set higher and a bigger pump put in such that the car simply ran rich in WOT situations and the base timing was set way down, it would likely survive a long time. It would have crap power and be a joke compared to what it would be with decent management. But it would likely be OK.
You get fuel based on the airflow as read by the MAF/AFM sensor which could care less what pressure is between the turbo and intake manifold. The additional flow through the AFM causes the ECU to try to deliver more fuel.
So while it is a horrendously bad idea to just run 5 psig with no fueling mods, the car will attempt to maintain the proper AFRs assuming it is an AFM equiped vehicle.
Frankly if the fuel pressure was set higher and a bigger pump put in such that the car simply ran rich in WOT situations and the base timing was set way down, it would likely survive a long time. It would have crap power and be a joke compared to what it would be with decent management. But it would likely be OK.
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02-21-2010, 06:17 PM
#47
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Except you neglect to figure something about the miata ECU into your theory that it refuses to enrich the fuel mixture significantly below 4000rpm. If the OP's friend wants to run a 5psi turbo on his car with a budget build bandaids are available and would work well enough to maybe keep the car alive for a few months...
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02-21-2010, 06:51 PM
#51
It looked to be about stoich when i had the wideband on my car before the megasquirt went on, im sure someone knows the furrealz answer to that though. Thats why on the stock computer i always felt a huge jolt of power right there.. VTEC mmmmmmmmmmmmmmmBAAAAAAAAAAAAAAAH!
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02-21-2010, 07:00 PM
#52
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I'll be honest here, I'm not an expert at tuning and I'm learning a lot as I go myself, I can just speak on a few things I know for certain and what I've learned. That dyno chart is from a 94 w/RRFPR along with a 5psi JRSC. Notice the AFR is lean as **** in boost below 4500rpm? As I understand the factory ECU won't add more fuel below that, which is why someone came up with the o2 clamp idea.
The point is adding positive manifold pressure to a factory stock naturally aspirated miata without any additional supporting mods won't last. Period.
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02-21-2010, 07:13 PM
#53
Stock form is irrelevant. Its when you add that mythical 5psi of boost and the ecu won't let you add fuel below 4k..
I'll be honest here, I'm not an expert at tuning and I'm learning a lot as I go myself, I can just speak on a few things I know for certain and what I've learned. That dyno chart is from a 94 w/RRFPR along with a 5psi JRSC. Notice the AFR is lean as **** in boost below 4500rpm? As I understand the factory ECU won't add more fuel below that, which is why someone came up with the o2 clamp idea.
The point is adding positive manifold pressure to a factory stock naturally aspirated miata without any additional supporting mods won't last. Period.
I'll be honest here, I'm not an expert at tuning and I'm learning a lot as I go myself, I can just speak on a few things I know for certain and what I've learned. That dyno chart is from a 94 w/RRFPR along with a 5psi JRSC. Notice the AFR is lean as **** in boost below 4500rpm? As I understand the factory ECU won't add more fuel below that, which is why someone came up with the o2 clamp idea.
The point is adding positive manifold pressure to a factory stock naturally aspirated miata without any additional supporting mods won't last. Period.
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02-21-2010, 07:46 PM
#55
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Join Date: Nov 2009
Location: Jax Fl
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I need to get that legendary software.. Nos_program_2.0
How else am i supposed to know when i have a danger to manifold situation?
Altho if it did in fact warn me of such occasions i would most likely scream shut up and slam the lid to my laptop.
How else am i supposed to know when i have a danger to manifold situation?
Altho if it did in fact warn me of such occasions i would most likely scream shut up and slam the lid to my laptop.
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02-21-2010, 08:00 PM
#56
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Its a little known fact that the slamming of the laptop is what caused part of the floor pan to come out.
Real racers know that when you blow the welds on your intake your blinker fluid catches fire and you loose the quarter panels.
Real racers know that when you blow the welds on your intake your blinker fluid catches fire and you loose the quarter panels.
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