mx5cartalk.com

Did some runs to compare the 2.
all the same cam settings
Timing is considerably more aggressive on the E85 map
change of spark plugs too
old ones were all crapped out
If youre turbo this is kind of irrelevant as the benefits are way better

Ive tried to make it as fair as possible & include SAE with air intake temp as they were done on different days

run this morning wasn't from 2000 rpm cause I had cars behind me..... top HP Numbers are only a guide really.So if you feel it is totally unrealistic say the word. Cause I'm not 100% totally sure.

Hmm, 104 vs 130 (25%) does seem a little unrealistic gain for simply 98 to e85. Most reputable shops suggest 5-8% is more likely.

Unless your spark map was massively low to start with, (ie lower than needed for 98) and tweaking it for the e85 put it back to where it should be?

98 spark table


E85

An old (2015) dyno plot from mine comparing 98 and E85.

Most obvious is the improvement in midrange. Note the car is now at 192 RWHP.

Airbox 98 octane vs E85 by Eipeip, on Flickr

ohh well looks like I might just have to wait until I'm back on the 98 for a while have another go.

Were you on the exact same stretch of road when collecting the data?

I've found in the past that VD is pretty sensitive to small changes in circumstances when collecting the raw numbers.

yes ive made a point of doing the smae strech of road....flat as possible or as the eye can tell.
start at the same point & put the pedal to metal.....2nd gear.....3rd I'll probably loose my license.

On my car Dyno tuned 98 vs dyno tuned e85 showed 6-7% gain over the entire range which matches with Marks tune. 25% I think means you 98 tune isn't ideal.

Pretty much a 20% gain on my car with E85 but this stuff is the good E85

Only problem is its $2.50/L The pump E85 has a heap less octane. This is the stuff they run on the supercars.

Yours Is turbo.
And it's lovely.

This was more about whats real or not. And virtual dyno. Yours was done on a proper dyno.

While virtual dyno has its purpose. And I have gotten same results on different runs.
Care needs to be taken when doing these runs apart from the obvious.

Straight road
Dry conditions wheelspin will give you fantastic HP....
Start at the same rpm
Start at the same location
Low traffic

But I've also noted how smooth your AFR is......nice

bear2230 wrote:
Pretty much a 20% gain on my car with E85 but this stuff is the good E85

Only problem is its $2.50/L The pump E85 has a heap less octane. This is the stuff they run on the supercars.

You can't crash a N/A thread about E85 with turbo data... that's just mean! I was happy with my 7% improvement.

With E85 and N/A it makes no difference on the quality of E85 as long as it doesn't have water or other impurities. You basically only need 40% ethernol to achieve max power with N/A as you should hit MBT with E40, unless your running 17:1 compression or something insane. This means you can pretty much mix E85 with 98 @ around 50/50 and still hit max power.

With the A/F ratio, the turbo guys have it easy. They don't have crazy cams or short intakes to deal and have fancy electronic stuff that makes things good so ignore Bear2230's curve. My A/F ratio is OK but it was tuned on a dyno per cell not on the street, but still it's probably moved a bit by now anyway as a few things have changed on my engine. I just check my data logs every now and then and make sure it doesn't go too high or low at WOT.

Hes just stirring the plot. And its working

Sent from my SM-G935F using Tapatalk

bear2230 wrote:

Pretty much a 20% gain on my car with E85 but this stuff is the good E85

Only problem is its $2.50/L The pump E85 has a heap less octane. This is the stuff they run on the supercars.

Richard, i want your boost

Sent from my SM-A520F using Tapatalk

E85 is not magic. Especially in an NA car. You've obviously done something not quite right.

Ive just reduced the spark on my 98 table & changed around the AFR's somewhat drastically.

I'll get the VE table dialed in over the next few weekends & do another power run.

Ive been using a bucket load of fuel. I figure that the heavy cams & idle peak hr traffic doesnt help. But I'll see if i loose any power. But 22l/100km is just a bit much.
Once that is all done I might also play around with cam advance & retard again.

Ive also got some 66lbs valve springs. I don't anticipate any major power increase with these. But I figure the current stock springs with a shitloads of km are probably toast. I don't intend to increase the RPM but it juts suddenly dies at 7000 rpm

My WOT AFR's are (or were) also a lot better dialed in than in the above graph. Not as smooth as bear2230 but much closer.