The E85 Sparkplug Thread

[joeyjoejoejuniorshabadoo]

as ethanol burns colder than pulp, e85 has differing spark plug requirements, so i figured we need a dedicated thread.

this thread is to list what you are using and how it performs.

just copy and paste this:

[b]CAR:[/b]

[b]POWER:[/b]

[b]TYPE OF ETHANOL:[/b]

[b]PLUG:[/b]

[b]GAP:[/b]

[b]COLD START:[/b]

[b]HOT:[/b]

[joeyjoejoejuniorshabadoo]

ok, i'll get the ball rolling

CAR: R33 (RB25DET)

POWER: 323rwkw

TYPE OF ETHANOL: Powerplus E85 (made by manildra, from wheatgrain)

PLUG: BCPR7ES

GAP: 0.9

COLD START: horrible, 10 odd cranks in winter

HOT: perfect performance once warmed up

i'm thinking of trying 5's but i would like to see some people's results with cold start on 6's first

[The Dan]

With all due respect, there is no one correct plug for any engine or power. The only correct way to determine what is the best plug for your application is to start with one, run it for 5000 and pull it out to see what she looks like. It is a good idea to see what others are running, though, so you know roughly where to start from. But where hp vs heat range is concerned, due to the colder burn of the ethanol, you'd be able to go back to a factory recommended heat range and work it from there.

[joeyjoejoejuniorshabadoo]

Yeah, I realise that but I thought having a reference might be a good idea for the future.

The other spark plug thread has determined a few fail safe options over the time it has been running And I am hoping for a similar result here

I might go for 6's @ 1.1 next time and see how I go...

[scotty nm35]

CAR: M35 Stagea

POWER: 250awkw

TYPE OF ETHANOL: Powerplus E85

PLUG: Denso IKH22

GAP: 1.1

COLD START: Woeful, I have to add 10% unleaded this time of year to get it to fire. Started this morning at 3 degrees with little issue.

HOT: Perfect.

From my experience ethanol burns hotter and faster when under high boost pressures, a colder plug will be fine. I doubt I will be changing plugs just to get the engine to start better.

Ethanol doesn't evaporate below 15 degrees which is why we have issues, its the petrol mixed in that fires for the first few rotations.

[joeyjoejoejuniorshabadoo]

Yeah... This is the reason we don't run e100 afaik

cold start doesn't really bother me too much, it's annoying when I am dailying it, but the ke70 should be finished pretty soon.... But I'll bet dollars to dimes I'll have that thing turboed and on the juice within 6 months anyway

[scotty nm35]

Mmm, high compression 20 valve 4ag running e85 on 25 psi.

You will be leaving the liner at home for good reason then!

[joeyjoejoejuniorshabadoo]

Don't know bout 25 psi lol... But the car only weighed like 900kgs before I stripped it so it should be a lot of fun

[VB-]

for the guys having cold start issues, add a massive amount of fuel, like 50% and take timing back to 0 or 5 degrees. it was something said by a tuner from the states, doesnt seem to have cold start issues, even below 0*c.

[scotty nm35]

There are a few drawbacks I see with that...

If you flood the bore with liquid ethanol it will run down past the rings into the oil and help to break it down.

It is still only the petrol firing, if you ran e100 it still wouldn't want to start well, also with below zero temps.

It would require an arftermarket ecu for those that just run larger injectors or higher fuel rail pressures.

I would have to give up the knock signal on my Emanage in order to wire in the temp signal, then I would have to get a cold retune.

I want to fit a small (say one litre) petrol canister in the engine bay, probably in 3 inch stainless pipe. I have the original fuel pump to slide in the pipe and one of the stock 370cc injectors will install nicely into the manifold. Power these from a simple push button on the dash and you're set. I have seen guys in the US running simpler systems they work very well and save wasting ethanol at startup

[VB-]

yeah just had a quick look over what i thought i read ages ago. seems its only good down to 5-10 degrees C, below 5 it doesnt work. i was confusing it with another one that cold started fine in freezing weather, but not on E85

[NYTSKY]

CAR: R33 GTST

POWER: 400+rwkw

TYPE OF ETHANOL: United E85

PLUG: BCPR6ES

GAP: 0.65

COLD START: 3 cranks

[joeyjoejoejuniorshabadoo]

did you run that gap on pulp?

[jarrod83]

sorry if this is off topic guys, but do the BCPR7ES also have horrible cold starts with pump gas?

Cheers

Jarrod

[joeyjoejoejuniorshabadoo]

nope perfect every time

[scotty nm35]

I think e85 cold starting will be an issue for those with lower compression more so than cold plugs, my VQ25det only runs 8.5:1 compared to 9:1 for the stock RB's. I need boost at startup.

I would really like to see somebody build an ethanol specific high compression engine with high boost, wish I had the funds to build one myself. Perhaps one day... if I keep pushing this one...

[NYTSKY]

did you run that gap on pulp?

No, it was .8 from memory.

I think e85 cold starting will be an issue for those with lower compression more so than cold plugs, my VQ25det only runs 8.5:1 compared to 9:1 for the stock RB's. I need boost at startup.

I would really like to see somebody build an ethanol specific high compression engine with high boost, wish I had the funds to build one myself. Perhaps one day... if I keep pushing this one...

One of my friends has a 9.5:1 CR (RB25/30) and his is a pig to start aswell.

[Simon-S14]

i would have thought to achieve better cold start you'd want to lean it off a fair bit.

how many tuners spend enough time on the cold start map anyway... the answer is not enough.

[The Dan]

i would have thought to achieve better cold start you'd want to lean it off a fair bit.

how many tuners spend enough time on the cold start map anyway... the answer is not enough.

+1

Spark plug is going to have f**k all effect on cold start - unless it's fouled of course

[scotty nm35]

Needs to be rich. As it is only the petrol igniting first up, you need more of it, or just install a fuel primer system like I am.