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E 70 vs e85 single turbo tuning. Also most popular spark plugs on 20psi and up

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E 70 vs e85 single turbo tuning. Also most popular spark plugs on 20psi and up

Old 04-07-18, 02:17 PM
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E 70 vs e85 single turbo tuning. Also most popular spark plugs on 20psi and up

This thread has two questions
I live in Missouri where the pump e85 is really like 70 to 75 and never hits 85 even in summer.
im tired of mixing e98 and the pump e70 to get e85 it is a huge pain
i have read a lot about the subject and it seems there really isnít any Benifit to running 85 vs e60 to e70!
So who is making good power on e70 it should still have the alcohol cooling effects and still be close to 100 octane.
im wanting to retune for this to make life easier and help a little in cold weather starting and running

2nd
The spark plugs Iíve been running are b10 egv
i recently rebuilt motor to losing oil line on highway was a huge disaster destroyed most of motor, I got lucky and picked up an fd w an aspec ported motor that was sitting around in some guys parents garage, sold Car kept motor for parts
when I pulled my old motor apart I noticed cracks at spark plug holes.
i read online some say the b10egv good to 700hp plus others recommended others and say there no good
just got Car back up and running going do a little break in then look to having it retuned

thank you
john
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Old 04-07-18, 02:20 PM
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How much boost on e 70?
car ran 21 psi
may try 25-26 if turbo still wants it
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Old 04-07-18, 05:53 PM
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#1 Run an Ethanol Content Sensor w/ an ECU that has target lambda values variable with Ethanol Content and LTFT and STFT able to hit those figures effectively.

Tune on what's available or what you're willing to put up with. I'm tuning on 91 octane and Pump e85 and the sensors are taking care of the work for me in regards to matching my target lambda values per ethanol content.

#2 Rx8 Spark Plugs and setting gap to 0.018-0.025"

I hope you have enough fueling for this... I'd expect 6x ID1700x's for really getting into e85 at higher power figures.
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Old 04-07-18, 06:14 PM
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Well I did install ethanol content analyzer but unfortunately I have a microtech lt10s so no of that will be happening I just figured I would tune to what’s available and keep an eye on ethanol content to make sure it’s consistent.
rx8 factory spark plugs ? What heat range are they
my fuel is I’d 1300 pri
id 1700 sec
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Old 04-07-18, 06:15 PM
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Also e 70 would be less taxing on the fuel system as well
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Old 04-07-18, 08:57 PM
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Knock suppression/combustion stability doesn't really improve on port injected motors above about E40. Gains above that are only very marginal due to extra evaporative cooling of the intake charge. You are wasting a lot of effort with mixing, just tune to what you get and check mix doesn't vary. If you are worried you could make a basic spreadsheet with your base tune flex % as an input and current flex reading which gives you a master fuel trim % to apply as a close enough offset. I'm going to offer my unhelpful personal opinion on microtech ecus for anything other than a race fuel only Billy cart. In the bin.

Plugs NGK 7756 R7420.11 could probably use a slightly hotter plug, 10s/10.5 likely to be ok on ethanol.

Last edited by Slides; 04-07-18 at 08:59 PM.
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Old 04-07-18, 09:42 PM
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I see your down the highway. Maybe we'll run into each other this summer.
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Old 04-08-18, 07:45 AM
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Where in Mo are you located ?

I know the microtech is not the most adavanced Ecu available but my car actually runs fairly decent and after the mess of losing oil line And rebuilding engine , I really don’t want to rewire car.
Maybe next year

I think I will just tune on e70 , when I first got this car I tested the ethanol content from the local pumps and 75 % was the highest even in summer, so it will be easy enough to add a little 93 oct to it to to keep it at 70%.
i will check those plugs out
but is the b10egv a poor choice?


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Old 04-08-18, 08:02 AM
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Would the 11 heat range be to cold for cold weather starts
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Old 04-08-18, 08:49 PM
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Originally Posted by johnrx2 View Post
Would the 11 heat range be to cold for cold weather starts


10s are probably fine, how much boost are you looking to run? Power goal?

The egvs are more likely to cause interference issues in electronics but the the microtechs do seem the handle that well if wiring is right, I don't think they reach quite as far into the housing either so there may be a very small running improvement there too. If you have a hand controller in the car and do run an independent flex sensor it is probably much faster and easier to bump the fuel trim, realistically no more than 1 or 2% with the ethanol content changes you are likely to see than trying to mix petrol back in.

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Old 04-08-18, 11:51 PM
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Originally Posted by johnrx2 View Post
Would the 11 heat range be to cold for cold weather starts
This is why you run heat range 9. Ethanol Blends are already harder to start, so why make things even harder?! On e70, you have about enough injector for ~425whp @ 3 Bar.

RE9BT eBay for 4x RE9BT @ $60
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Old 04-09-18, 10:11 AM
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The car made more power w less injector before. At 21 psi 503 whp . I’m not really sure what duty cycle was it was like that when I bought it
the old owner sent me a video that showed dyno run .

My old car made 424 whp on one dyno
and 418 whp on another. At 15 psi!
! This setup at 21 psi is much faster
so I don’t buy that I can only make 425whp? On e70
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Old 04-09-18, 01:00 PM
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Ok just realized at 3 bar that s my base pressure so at 20 psi I’ll be at 63psi what can my injectors handle at that pressure?
e70
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Old 04-09-18, 10:02 PM
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Originally Posted by johnrx2 View Post
Ok just realized at 3 bar that s my base pressure so at 20 psi Iíll be at 63psi what can my injectors handle at that pressure?
e70
unless your injectors are pre-turbo and you are still running a manifold reference reg the differential pressure across them which drives flow will still be 3 bar. That is the whole point of the referencing system so that increasing/decreasing open time gives a linear response regardless of being in boost/vacuum and dead time is consistent.
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Old 04-09-18, 10:58 PM
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Originally Posted by Slides View Post
unless your injectors are pre-turbo and you are still running a manifold reference reg the differential pressure across them which drives flow will still be 3 bar. That is the whole point of the referencing system so that increasing/decreasing open time gives a linear response regardless of being in boost/vacuum and dead time is consistent.
Yes, but his fuel pump will be at 63psi + pumping losses, so likely somewhere around 70psi. Following your voltage vs. pressure chart from your fuel pump manufacturer, you can tell pretty quickly that you'll be running out of pump on e70.

By increasing nominal fuel pressure, the injectors will increase flow at the expense of dwell time, but that will continue to bring your fuel pump threshold down (it'll have the capacity to make less power as it flows LESS as pressure increases).

Either way, you're topped out in the mid 400s without at least two fuel pumps and a raised nominal fuel pressure.

Your Injectors = 6120cc/min @ 100% DC @ 43.5psi (3 Bar)

A lot of guys run Dual Bosch 044s at 75psi nominal pressure and those 4x injectors can now do 8110cc/min @ 100% DC @ 75psi, but now with more heatsoak, and fuel pumps running roughly 101.5psi comparatively. Those pumps don't mind the high pressure, the Walbros are terrible for anything over 3-4 Bar nominal. Pierburg makes nice pumps as well...

At this setting, you can crack 500whp, but fuel temps will create cavitation issues as the vehicle is driven for longer durations. It would be almost mandatory to run a fuel cooler. I prefer the -8AN Derale units with Twin Fans.
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Old 04-10-18, 11:07 AM
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Originally Posted by johnrx2 View Post
Where in Mo are you located ?

I know the microtech is not the most adavanced Ecu available but my car actually runs fairly decent and after the mess of losing oil line And rebuilding engine , I really donít want to rewire car.
Maybe next year

I think I will just tune on e70 , when I first got this car I tested the ethanol content from the local pumps and 75 % was the highest even in summer, so it will be easy enough to add a little 93 oct to it to to keep it at 70%.
i will check those plugs out
but is the b10egv a poor choice?


I'm down the highway in Columbia. I'll be there for some Cars and Coffee and other rotary events.
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Old 04-10-18, 04:18 PM
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Here are the build specs
engine rew block
turblown stud kit, goopy seals , rotating assembly balance,
large street port
turbo is some form of t04s I have the specs written down just had it rebuilt while Car was apart and they measured it

fuel
a1000 fuel pump good to 1000 forced induction (not Rotary or ethanol)
id 1300 x primary
id1700x sec

water injection pre turbo comes on at 15 psi

i would think the a 1000 would hold up fine to my turbo,
even though it’s really noisy.

if it becomes a real problem I will down the line add two more 1700s
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Old 04-10-18, 06:50 PM
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Originally Posted by johnrx2 View Post
a1000 fuel pump good to 1000 forced induction (not Rotary or ethanol)

i would think the a 1000 would hold up fine to my turbo,
even though itís really noisy.
Here is your problem. The A1000 is absolute **** for high pressure (turbocharged) applications. My whole strategy I wrote to you above about how the Bosch 044 kicks everyone's *** over 70psi pump pressure and how you could "stretch" the 4x injectors to your needs by higher base pressure doesn't work if you have a pump like this. You could add 12x ID1700x and your problem would still be the PUMP...

So that's the part you need to address.
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Old 04-10-18, 07:00 PM
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Can the Bosch pumps be ran externally like the a 1000
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Old 04-10-18, 07:23 PM
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K just found video of external Bosch 044 . If I run two can they t into one feed line going to motor , or need to run separate line s
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Old 04-10-18, 08:42 PM
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Originally Posted by johnrx2 View Post
K just found video of external Bosch 044 . If I run two can they t into one feed line going to motor , or need to run separate line s
You would tee them. This has been done for well over a decade and is incredibly well documented. A simple search will find you exact part numbers you need to do so. -8AN Feed (IN/OUT) and -6AN Return.
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