Is my buddy being dumb?
#43
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.
#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.
#47
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...
#52
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Join Date: Jun 2007
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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.
#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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