Gotcha. Forgot you renesis guys use some voodoo to make those things run....

 

That voodoo of which you speak is the oem ECU .... a much underated bit of kit IMO. Not that I've run a stand alone to see all the differences but if it weren't for the ability to tune in real time I would never even contemplate one.

 

Hmm brettus u must just have a magical fuel pump lol i will probly just go the surge tank route since i do track the car and dont want to give up flex fuel sensor.

 

No, it’s better/safer/smarter for the flex sensor to be pre-injector to read and adjust fuel prior to injecting rather than after it’s too late. You can split the fuel line and run a parallel fuel line around the flex sensor to eliminate any restriction

 

Lol... I doubt that you would ever have an issue.

It's not like there isn't a lot of bypassed fuel with most return setups. I have chucked 5 gal of E85 into 1/2 tank and ran the fuel pump to see how long it takes to normalize the readings. It is minutes...

Can't think of a scenario that you would have an issue

 

Well I wouldn’t run a bypass at all, but putting it in the bypass assumes there must be sufficient flow there and there are certain but obviously rare situations where that could potentially not happen. You can decide for yourself if it’s worth the risk or not.

 

What's the risk ? It's not like the ethanol content changes half way through a tank .

 

FWIW, JASMA is not a brand. JASMA is the acronym for the Japan Automotive Sports Muffler Association. The stamp that you see on many Japanese made exhausts is simply an acknowledgment that the piece meets JASMA requirements.

 

Interesting,
never knew that

 

Thank you I didn't know that.

 

What’s it going to read if the flow is too low, like your pump goes off some, not enough to starve the engine and potentially trigger other safety guards, but insufficient flow to the return? In that situation you can potentially go from maybe mild scare to boom. It’s a known potential issue by pro tuners. Some systems have ways to safeguard against it, but you need that and an understanding on how to set it up that way.

Everything has pros and cons, but you at least need a basic understanding of them to avoid problems.

 

I really don't think there is a wrong answer here. If I change my ethanol content significantly, it usually takes about 5 minutes max of driving before all the fuel homogenizes. I have seen in my logs that under WOT where the ethanol content has a weird fluctuation (usually no more than 5%) which I attribute to the return line getting less flow than normal (which does seem to affect the sensor reading). In my case this change does not seem to make a real big difference in air/fuel readings so I have no need to make any changes.

 

There’s no wrong answer, but what I posted previously has nothing to do with what the E content is. In order to get a consistent output reading there has to be sufficient flow going through the flex sensor. If there isn’t the readings can get a lot more erratic than what you saw and put your engine in a potentially fatal running condition if your pcm doesn’t have a strategy for addressing it.

.

 

Meh ....... Better off without it judging by that . From what I've gathered over the last few years .....so long as you have a decent amount of ethanol in there ...... you still get good knock protection . I actually go from 30% down to 10% regularly when on a trip and there is no E85 pumps. I lower boost down to 10psi on E10 and it just runs richer under boost on same tune .

 

Would seem you were wrong on that prediction

https://www.rx8club.com/series-i-maj...-build-270295/

Mine spools faster and equals or betters the power at the boost level quoted.

 

Well if that makes your ego feel better then fine. I don’t entirely agree with his build, but it’s his build. Not to mention it only just started.

 

I only bring it up because you came down pretty hard on me and was adamant I was doing it all wrong ....... time has proved otherwise.

 

No, there haven’t been that many builds. Technically he only has 4 port engine too since the AUX are non-functional, not that it really affects what we’re discussing. More are coming. Let’s see what happens when someone puts as much time as you have in yours and turns it up with full E85.

but to be honest I never was able to back it up with my own results, that is the truth.

 

You have a point .... maybe I jumped the gun a little . It's just that I always thought the low mount would have an insurmountable advantage over a top mount due to the much lower volume . I think it'll have to be a 7670 to beat what I have for spoolup but yeah ................. give it some more time.

 

Well understand it’s not like he contacted me and we designed it out together. Which we don’t even have all the facts on what he has much other than some general text description. I like Elliott and think he’s done some good work with the FD3, but I tried discussing the Renesis app with him and he can’t get past common rotary theory any more than most other people. You at least tried a lot of unconventional ways to address things and learned a lot the hard way. We disagreed on some of that, we disagree on some of what you have now, but I also disagree with some of what I do know about that particular turbo setup he has too. I’m encouraged by his initial effort, but I didn’t endorse it in any way. He’s not really turning it up so to speak; only 12-13 psig actual boost he said and he even claimed that hitting 16 psig at 4200 rpm once was a “mistake”.

I get that a Renesis won’t duplicate an REW, but they now make over 30 psig boost by low 3xxx or less rpm on this turbo with full E85. So IMO there definitely is something more to be had than we’ve so far on a Renesis using this turbo.

 

Brettus what conditions are u quoteing 14psi by 4000 rpm? Id like to do an apples to apples road comparison say 1 to 1 gear ratio( 4th for u 5th for me) From 3000 rpm?

Also i live at 4000ft so my turbo does need to work a bit harder for the psi

 

I see 14psi by 4100 in 3rd gear which is pretty close to your 3rd gear. That's starting the log at 2500 . Better than that in 4th and 5th obviously. 4 th is 1 to 1 on my 5 speed.

 

3rd gear on the RX8 is 1.484. So about midway between 3rd and 4th gear on the 6 spd

 

1.391 according to my info ....
My very first setup ,with ported engine, actually spooled better than the current one . I've managed to lose a bit by trying for higher peak.
Lost 100rpm going to gtx3582 compressor , lost 100rpm by not quite porting current engine enough, lost 150rpm going to 1.06 vs 1.01.

 

So thats even close to my 4th thats why id say we just do a couple 1 to 1 pulls and see im betting i will only be 2-300 rpm later