Corn squeezins, learn me please.

So as some of you know, I play around with a CSPish 1997 Miata. It's been a labor of frugality all along and I spend pennies compared with some people's benjamins to go fast in a parking lot.

Last month I happened across a piggyback computer for late NA8 Miatas (Xede) in a trade, so that should do engine management. What exactly would I need to buy/find to install in order to move to E-85? From what I've heard it should be worth 20-30 hp to make that leap (along with the tune). That aught to be enough extra oomph to put me slow butt into competition for some FTD plaques.

So help a brother out, what do I need, where do I get it, and what can I skip?

My go-to is Four Roses but my favorite "regular" is Turkey 80. Oh, wait....

Check with Bell Engineering to see if the Xede can actually handle what you're asking. See what its capabilities are. You may want to advance the timing - can it do that, or only retard?

20-30 hp is what I would place in the "wildly optimistic" range. We've worked on top-level CSP cars and I can pull the dyno charts to confirm, but my SOTP estimate is going to be more like 5-8.

I had a bunch of friends running E85 on cars (rowdy Evos and the likes) and it always seemed more hassle than it was worth. They were always complaining that they couldn't find a station that sells it, or that the station was out of it, or that the quality/mixture was off.

Hmmmm. Well none of that is what I was hoping to hear.

Availability of E-85 shouldn't be too bad, I hardly drive the stupid car anymore. It's become a garage queen/autocross toy that I'm too poor to fully take advantage of and travel around to track days or National events.

E85 requires more fuel flow, so you'll probably need larger injectors, and perhaps even a new fuel pump depending on what you're currently using. It's great for boosted vehicles, but it seems like a lot of work on an NA engine.

Not for nothing, but considering your location, you may want to consider tuning for moonshine. Probably cheaper and easier to come by in your neck of the woods. LOL!

STM317 wrote: E85 requires more fuel flow, so you'll probably need larger injectors, and perhaps even a new fuel pump depending on what you're currently using. It's great for boosted vehicles, but it seems like a lot of work on an NA engine.

Depends. On the low compression of an NA, it's probably not worth much.

In newer high compression engines, like my BRZ which is 12.5:1, it's worth 15-20whp. And a huge jump in the midrange.

Any more specifics? Has anyone here actually done this on a Miata?

Question- how much are you willing to do to the engine?

Last time I read the rules, you are allowed to skim the head- either the spec amount in the manual (which I bet doesn't exist for a Miata) or a rule spec (which I can't recall the rule). That would raise the compression nicely.

The other thing you really need is the MBD data for a 1.8 Miata, and compare that with the stock spark timing- you should be able to run MBT more much more often, even with the slight raise of compression ratio.

Put that with the legal limit to porting (which can be DIY), bigger injectors, and a larger fuel pump, and you should be all set. I think it's fair to run WB control, too- as it will give you enough info to be flexible for the nominal spread of E85's percent ethanol. And since you would change the controller, you can also change LBT to be richer so that you get the max power out of the fuel.

Doing a "patch" with parts to run on the original ECU can't really compensate for all of the raw fuel benefits.

conesare2seconds wrote: My go-to is Four Roses but my favorite "regular" is Turkey 80. Oh, wait....

You should switch to Evan Williams, it's a lot cheaper and a lot less harsh too.

Knurled wrote:

conesare2seconds wrote: My go-to is Four Roses but my favorite "regular" is Turkey 80. Oh, wait....

You should switch to Evan Williams, it's a lot cheaper and a lot less harsh too.

If you can get it spend the extra couple bucks on the white label 100 proof bottled in bond version. I find it kinda boring to drink straight but it's really good for mixing.

BrokenYugo wrote:

Knurled wrote:

conesare2seconds wrote: My go-to is Four Roses but my favorite "regular" is Turkey 80. Oh, wait....

You should switch to Evan Williams, it's a lot cheaper and a lot less harsh too.

If you can get it spend the extra couple bucks on the white label 100 proof bottled in bond version. I find it kinda boring to drink straight but it's really good for mixing.

Since my supply of W.L.Wellers has dried up over the last couple of years I've largely switched over the Evan Williams 1783. A true small batch at a very reasonable price point (re: cheap).

conesare2seconds wrote: My go-to is Four Roses but my favorite "regular" is Turkey 80. Oh, wait....

Single barrel is nice. Also enjoy a good buffalo trace from time to time.

Try Old Grandad Bonded (must say Bonded). It's way better than its price suggests. I'll be a Turkey 100 man til I die, though. Also a fan of buff trace and the EW 1783 is solid too.

Only on the internet. Has anyone tried any of these "blends" in an engine.

KyAllroad mentioned not running the car much. Alcohol does not store well as many have attested to when running E-10/15 in their lawn equipment. The sealed system on a car might make a difference.

KyAllroad wrote: Any more specifics? Has anyone here actually done this on a Miata?

I checked with Jeremy here. We've tuned a few top CSP guys. Switching to E85 usually netted them about 4-5 hp. That's on engines already built to the limit of the rules, so they're as high compression as is legal in the class.

Keith Tanner wrote:

KyAllroad wrote: Any more specifics? Has anyone here actually done this on a Miata?

I checked with Jeremy here. We've tuned a few top CSP guys. Switching to E85 usually netted them about 4-5 hp. That's on engines already built to the limit of the rules, so they're as high compression as is legal in the class.

Ah, thanks. Probably not worth it then for my level of commitment to autocross. Mazda did a pretty good job optimizing the BP engine (for the era it came from), it's frustrating trying to get any significant bump in ponies out of it.

Yeah, it's crude but strong. Which is why forced induction has been such a solid choice for so long.

Now, those CSP cars were pretty darn healthy. I just pulled up one dyno chart and it's making 179 rwhp. But if I were chasing more power, I wouldn't start with E85 due to the hassle factor. I'd go for compression and engine management.

Keith Tanner wrote: Yeah, it's crude but strong. Which is why forced induction has been such a solid choice for so long. Now, those CSP cars were pretty darn healthy. I just pulled up one dyno chart and it's making 179 rwhp. But if I were chasing more power, I wouldn't start with E85 due to the hassle factor. I'd go for compression and engine management.

But compression and engine management make E85 so much more tasty!

yeah, it opens up the door for 5 hp increases

I said start with. You'll get a hell of a lot more out of compression and management in the first place.

For bumped the HP by reported 10% on the ZX2SR (Zetec) by just an ECU change and a small increase in air intake.

Keith Tanner wrote: yeah, it opens up the door for 5 hp increases I said start with. You'll get a hell of a lot more out of compression and management in the first place.

Oh I thought you meant REAL compression increase. Not just skimming the head.

z31maniac wrote:

Keith Tanner wrote: yeah, it opens up the door for 5 hp increases I said start with. You'll get a hell of a lot more out of compression and management in the first place.

Oh I thought you meant REAL compression increase. Not just skimming the head.

Skimming the head is the only legal way to get a specific engine's compression up. Can't mix and match parts between years to accomplish that, have have to use OE pistons and rods. Just like cams are tricky, too- as they have to be the original ones, too- but VCT (if equipped) can be tuned or you can use sprockets that can be changed.

The tight rules are the major reason to run E85, as 5hp might help at the tippy top of racing. And one thing to consider- the cost of moving to E85- even including all of the allowed changes- may be cheaper than the cost of shocks in CSP.

It's an odd class, in that regard. Other than the fact that SP cars are generally road legal- it may be a better investment value to build a Prepared or Modified car (I think DP, DM, and EM is where the Miata can fit).

I found, on my ZX2SR, that an underdrive pulley to be a better power producer than many of the usual stuff.

Not even mentioned any more.