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The stock setup is 1:1.

What you stated very simply before was "If they weren't needed, manufacturers wouldnt use them, tuners wouldnt use them, and they'd be a thing of the past." which as respectfully as possible is inaccurate.

What you're stating very simply now is "they are a necessary item on a properly setup forced induction motor." which as respectfully as possible is simply inaccurate.

IF they are needed, they are needed. If not they're not. That's the point here and having a stock 80, SC'd 80 or a properly sized and setup Turboed 80 (the sweet AVO system not included) doesn't seem to "need" one.

I'm happy to share whatever you would like to look at in regards to my setup and I have tons and tons of data to support that my setup runs wonderful well, it is reliable, safe and powerrrful.

I'm not saying you are wrong with any other vehicle out there, I'm simply saying that with the 80 and several specific setups you don't need anything above 1:1 FPR.

See other thread. All EFI software assumes a "given" Bar Pressure Differential as a constant. The *variable* is the uncalibrated MAF voltage slope. Don't confuse the two. I'm having a difficult time accepting the 80 is the 'only' EFI Ecu that doesn't 'need' FPR Pressure Differential to be a constant. If you had a voltage slope of the modified MAF, you might be able to make that claim without the software code. You still have the problem that the software 'assumes' 3Bar pressure differential in calculating Injector Flow Rate.

Be careful of your claims here. They aren't innacurate, they are just wrong. With 10psi boost at 5000ft capping the FPR you have 15% less fuel going thru your injectors, at a less than optimal spray pattern. See posts 95-107 in the MAF thread.

Scott J
94 FZJ80 Supercharged
 
Let's get back to basics... I could care less what Safari does, let's speak to how RRFPR's work. The math simply confirms, with a RRFPR capped, and running 10psi boost, you have reduced the output flow of your fuel injectors by 15%. It's not theory, it's how FPR's work.

Scott J
94 FZJ80 Supercharged

If you really want to get back to basics, stop spamming the thread, or talk about the dyno charts above, that is what this thread is about. I guess you didn't have a big enough audience in the appropriate threads, to satisfy your megalomania...
 
See other thread. All EFI software assumes a "given" Bar Pressure Differential as a constant. The *variable* is the uncalibrated MAF voltage slope. Don't confuse the two. I'm having a difficult time accepting the 80 is the 'only' EFI Ecu that doesn't 'need' FPR Pressure Differential to be a constant. If you had a voltage slope of the modified MAF, you might be able to make that claim without the software code. You still have the problem that the software 'assumes' 3Bar pressure differential in calculating Injector Flow Rate.

Be careful of your claims here. They aren't innacurate, they are just wrong. With 10psi boost at 5000ft capping the FPR you have 15% less fuel going thru your injectors, at a less than optimal spray pattern. See posts 95-107 in the MAF thread.

Scott J
94 FZJ80 Supercharged

Scott for the last time, I'm not running without reference. I've repeated that ad-nauseum. And I already know all the things you regurgitated here. And I never confused MAF voltages with anything else anywhere. And I never made any claims otherwise. Just because you twist these things in your mind doesn't mean anyone else is even coming close.
 
Scott for the last time, I'm not running without reference. I've repeated that ad-nauseum. And I already know all the things you regurgitated here. And I never confused MAF voltages with anything else anywhere. And I never made any claims otherwise. Just because you twist these things in your mind doesn't mean anyone else is even coming close.

Glad to hear you made that swap.... Looking at posts 172 and 195 in the MAF thread, you added this reference line when this year? Ok, what's your rail pressure at 10psi? It seems we have partial progress, some with the modified MAF running manifold reference, and some without the manifold reference. What's your observed LTFT with the manifold reference hooked up vs plugged? You made several claims in the MAF thread that indicate confusion between OBDII scanguage readings and MAF voltage slopes. What are you doing about the modded MAF value changes to 'calculated' load and ignition timing values closed loop?

I tend to focus on the meat of the problem.... An installed MAF that has never been properly voltage sloped. With or without manifold reference sensor. If the software is a given, then the RRFPR manifold reference is a given as well. This has nothing to do with 'need' as you propose 2 posts ago, it has to do with software programming constants. What EFI systems *don't* "need" or use manifold FPR reference?

Scott J
94 FZJ80 Supercharged
 
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the ones on

Toyota: Camry, Avalon and Corrolla

Lexus: ES300, RX300 and GS430

There are more but that should keep you busy verifying that they don't have a reference line to their FPR.

Or weren't you talking to me?


OH SNAP:D
 
the ones on
Toyota: Camry, Avalon and Corrolla
Lexus: ES300, RX300 and GS430
There are more but that should keep you busy verifying that they don't have a reference line to their FPR.
Or weren't you talking to me?

Not true at all, be careful how you phrase this.... These cars absolutely *do* use a constant Fuel Pressure Differential at the rail, it's just designed differently. These cars use a returnless FPR mounted in the tank, this maintains the required fuel pressure differential to eliminate the need for a return line. This feature was added to many vehicles in the last 10 years, mostly to reduce EVAP emissions.

I'm pretty sure Christo references this in the MAF thread. These EFI systems modify the duty cycle of the Fuel Pump to achieve the proper Fuel Pressure Differential. The advantage of these systems is the ability to change the effective size of an injector for peak power and torque.

The key concept to understand is that the Fuel Pressure Differential is a Constant in EFI systems. The above vehicles you reference use in tank FPR maintain a constant Fuel Pressure Differential at the rail.

HTH

Scott J
94 FZJ80 Supercharged
 
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Scott, by now I think we all get what you are saying and there is no need to beat this tired horse any longer in this thread or any other one remotely connected to my MAF.

I've talked with the machinist and am moving forward with a tuning sleeve.

Mission accomplished on you and Slee's part!
 
Scott, by now I think we all get what you are saying and there is no need to beat this tired horse any longer in this thread or any other one remotely connected to my MAF.
I've talked with the machinist and am moving forward with a tuning sleeve.
Mission accomplished on you and Slee's part!
What are you tuning? Don't you need the voltage slopes of both MAF's for that? How else can you do it? Seriously.

There are 300posts in the thread Christo entertained, with many questions unanswered by the information you have presented to date. IMO, you have a very incomplete baseline understanding of how and what the FPR or the MAF mod does. If you don't have the voltage slopes of the MAF, you can't claim anything (or tune anything) because you don't have the proper data to do so.

You recently point to a 'returnless' fuel system (also in post 105 on the MAF thread), not found on the 80, which Christo correctly pointed out was a different system (post 106 MAF thread). It's not the same as the 80, but the principle is the same = Fuel Pressure Differential is a constant. When you 'toss' it out as some sort of 'proof' a returnless system is somehow 'different', it appears to demonstrate you don't know how that system works either.

Mission accomplished? I tried to get this information across 2 years ago, and was told by a moderator then to leave it alone. With 150 of these units now sold, the basic issues don't change, and the relevant data to your claims is still missing. When Toyota designed the stock MAF tuning insert, it also programmed the software to reflect the engineered design voltage slope. How can you make a "tuning sleeve", if you don't have the voltage slopes of the stock or the modded MAF?

You should be able to claim a mod is 'better' based on data collected. Christo tried to point you to what data you need to do that. The other data isn't relative yet. Nor is any conclusion of better, great, dumb or POS. Don't confuse my claims. Without the proper data, I can't say whether your MAF mod works or doesn't - neither can Christo. I can explain how these components work in stock and modified EFI systems.

Thanks for your tolerance. Feel free to correct any of my technical posts if you find them in error.

Scott J
94 FZJ80 Supercharged
 
What are you tuning? Don't you need the voltage slopes of both MAF's for that? How else can you do it? Seriously.

There are 300posts in the thread Christo entertained, with many questions unanswered by the information you have presented to date. IMO, you have a very incomplete baseline understanding of how and what the FPR or the MAF mod does. If you don't have the voltage slopes of the MAF, you can't claim anything (or tune anything) because you don't have the proper data to do so.

You recently point to a 'returnless' fuel system (also in post 105 on the MAF thread), not found on the 80, which Christo correctly pointed out was a different system (post 106 MAF thread). It's not the same as the 80, but the principle is the same = Fuel Pressure Differential is a constant. When you 'toss' it out as some sort of 'proof' a returnless system is somehow 'different', it appears to demonstrate you don't know how that system works either.

Mission accomplished? I tried to get this information across 2 years ago, and was told by a moderator then to leave it alone. With 150 of these units now sold, the basic issues don't change, and the relevant data to your claims is still missing. When Toyota designed the stock MAF tuning insert, it also programmed the software to reflect the engineered design voltage slope. How can you make a "tuning sleeve", if you don't have the voltage slopes of the stock or the modded MAF?

You should be able to claim a mod is 'better' based on data collected. Christo tried to point you to what data you need to do that. The other data isn't relative yet. Nor is any conclusion of better, great, dumb or POS. Don't confuse my claims. Without the proper data, I can't say whether your MAF mod works or doesn't - neither can Christo. I can explain how these components work in stock and modified EFI systems.

Thanks for your tolerance. Feel free to correct any of my technical posts if you find them in error.

Scott J
94 FZJ80 Supercharged

I started a thread just for you. For everyone's sake take all this stuff over there and stop high jacking all these threads.
 
I started a thread just for you. For everyone's sake take all this stuff over there and stop high jacking all these threads.
No hijack, CycloSteve has access to a dyno, a lot of EFI tuning expertise at 034Motorsports, and can log the voltage slopes of the MAF stock and modded. No need to start a separate thread for that.

Thanks tho!

Scott J
94 FZJ80 Supercharged
 
Steve,
Did you ever do a 3rd run with LT's old MAF or his sleeved MAF?

Cheers,
Salue
 
No 3rd Dyno run as of yet. My cracked-cylinder head then effed-up front-end last year pretty much has kept me from doing any new "runs" at 034. Plus my rear ARB started acting up recently (not always instantly disengaging), so I am a bit leery of putting that sort of stress on the rig until I can sort out why.

All said, I have been running the new LT sleeved-MAF for six+ months now with no issues. Ran some tests with my Wideband sensor installed, and the AFR's were always well within spec under various throttle levels and boost, and it did much better than the stock MAF.

:cheers:

Steve
 

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