t-von

iTrader: (8)

Engine set-up is a NA 20b with ITB's.
Built from scratch intake.
Haltech E11v2.
Ls1 Coils.
9.7 compression rotors
NEW Leading plugs 7's
NEW Trailing plugs 9's
Fuel is 87 octane w/premix
I'm doing no load tuning that's why I'm using 87 for now


Ok back in November when I 1st got the engine running in my Fd, I had issues with intake leaks causing a high idle and glowing red headers. Since my engine is moved mack with-in the chassis, I decided to remove the engine and put it on a test stand so I could run it and fix all my little quirks. Once I fixed the leaks I was able to tune the engine to 13.5 AFR's and bring the idle down to 750 rpm's. Happy about my progress, I then started having starting problems. This is my 1st time tuning any kind of ecu so I started making fuel adjustments to figure out the problem. That didn't work. I figured that running the engine for so long with intake leaks may have fould out my new plugs. I removed them and this is what I saw on the 7's.



Notice how the center electrods already look worn? I had an extra set of plugs from my 2000 BMW M5 that were actually the same length so I installed them to see if the engine would run again. Well it fired right up and ran perfect. So damn in about 5hrs run time I was able to ruin my leading plugs by running my engine too hot. Or so I thought! I went back to Orielly's and bought 3 more leading plugs. The trailing still looked great to I resued them. With new 7's back in the leading, the engine fired right up and allowed me to do some low load tuning on my engine stand. Base timming was set at 20 degrees advance with 15 on the split. I can rev up to 7,500rpms for now with A/F ratios in the mid 12's. I still gotta lean it out some. Now here the weird thing, I've been having hard starting problems again. I pulled the newly replaced plugs and they look exactly the same as the orginal 3. This was only after another 5hrs of run time. WTF??? I reinstalled my BMW plugs again and the engine runs perfect. Sooooo! What could I be doing that's causing my electrods to be wearing so fast on my leading plugs? My engine is currenty apart for some more experimenting mods and should be back together over the next couple weeks. I know I shouldn't be having these kinds of problems with 7s in this situation.

rotarygod

iTrader: (1)

FWIW I run all 9's in a stock n/a street driven 2nd gen. I constantly killed 7's.

peejay

Are you running 20 degrees at idle, then?

mazdaspeed7

I had the same issue with my n/a engine after I ported it. It was killing plugs in 2k miles. Switched to B9EGV's all around and never had another issue. Ive even run as cold as 11's on a heavily ported n/a motor with no plug fouling.

j9fd3s

iTrader: (3)

whats the dwell setting? what happens of you swap the leading coils vs trailing?

ive actually been tuning the PP on autolites, under $3 a plug....

IMO a 20b should run on 7s and 9's, those are colder than stock, but the PP didn't like the breq style plugs either...

if it was mine, i'd make sure the coils all work, and keep tuning with cheaper plugs, the m5 plugs bkr6e are also under $3... heat range 6....

t-von

iTrader: (8)

I beileve so. When I unlocked the timming, it jumped up to 20degrees across the board.

t-von

iTrader: (8)

Don't remember the dwell off the top of my head. The engines been down since December as I've been concentrating on all the body work. When I get it back together and hooked up, I'll check my settings. I will also try swapping the coils since they were bought used. Were did you pay $3 for the Bimmer plugs? I think I paid $9 each for mine. My engine is a side port!


Edit: I just re-checked the Haltech section were I got my set-up tips from. By Dwell do you mean charge times? 4ms is what I'm running.

https://www.rx7club.com/haltech-forum-62/haltech-installation-diagrams-setup-tips-850059/

Number 3 in the 1st post is my ignition set-up.

j9fd3s

iTrader: (3)

yep charge time. i've seen a thread i think on efi 101 where they scoped out the ls1 coils. 4ms sounds about right off the top, but you might wanna look at make sure.

http://www.ngk.com/Default.asp

they have choices but the $3 plug would be good to tune on!

stock idle timing is -5BTDC L and -20BTDC T, the early cars run TDC and -15 BTDC T.

i notice going over 10 BTDC L the idle gets rougher. the actual number you settle on doesn't much matter unless you need to pass emissions.

the s5+ cars actually use timing to trim the idle speed, lower than 750, they add timing, and over that it takes away, i have a graph i need to scan. they add/take away up to 5 degrees.

they also seem to consider 500-1100rpms the idle zone, so over 1100 timing is free to advance, in which case 20 is better...

you won't hurt it running 20 all the time, they want the PP running 20 all the time, but its not optimal at low engine speeds...

mike

peejay

I used to run full (mechanical) advance all the time, but for the half bridge I put one of the springs back in to take away some advance at idle. Less advance means lower intake vacuum means it can idle smoother. Even stock port rotaries don't "like" lots advance at idle, high idle vacuum means more exhaust gases pulled up.

Not that this has much to do with anything, other than I've noticed that more initial advance seems to make plugs last longer.

t-von

iTrader: (8)

After looking at my video again, my timming is at 20 BTDC. I affixed my intake to take advantage of the FD's BAC valve to help with cold start idle and idle up for A/C. When it's duty goes to 0, my idle drops to 750 and it's very stable. Only thing I can think of is swapping the coils to see what will happen.

j9fd3s

iTrader: (3)

ive been playing with my 58 tr3 lately. carbs were rebuilt forever ago, but in the digging the car up and getting it running process, i resynched (sunk?) them.

since starting from a fresh tune etc etc, i've been driving it for a day or so and then pulling the plugs and see how they look.

its been fun tuning it the old school way, i keep a simple journal/log and it took about 3-4 days to have it running really nicely.

i did try to set it up with the wideband, but the old school way worked better. it lets you concentrate on how the car actually runs, instead of making a digital readout read a certain number

Dudemaaanownsanrx7

iTrader: (23)

get some iridium plugs. The electrode is a much more durable material and smaller so it lasts longer while giving a hotter spark.

diabolical1

iTrader: (3)

T-von, whenever you get back to tuning, for what it's worth, when i used to kill plugs constantly (while tuning my Dell'Orto), i simply switched plug types. i don't know if you're opposed to it or not, but you may want to try an NGK B_EV or B_EGV-type plug. i found my engine was quite happy running 7s or 8s in the lead and 9s in the trailing. on my brother's car, i ran 7L/9Ts when it was carbureted, and that's where i plan to start when tuning the fuel injection.

robertgibbson@yahoo.com

For a Volvo I would stick with Bosch, they sell some good ones available at most auto parts stores.
the Bosch Platinum Ir Fusion looks good
As for your car specifically I wouldn't be able to comment. Your car may have a plastic cover over the engine that would have to be removed. Look for a Haynes Or Chiltons manual specific to your car, it will give you step by step instructions.

t-von

iTrader: (8)

Thx for the advice guys but there has to be a logical problem here cause I see no reason why my engine can't reliably run with FD style factory plugs in place. It makes no since under these non severe conditions. I'm starting to think that I may need to re-zero my timing to make sure it's correct. I've done it three times in the past already. Maybe I'm doing something wrong there? Since I'm running a Haltech, I used the notes from the Hitman site. Anyways, I forgot to update this thread! I had the engine up an running a month ago and noticed that my idle timing was actually 8 BTDC and not 20. It only jumps up to 20 above 1000 rpms. So my timing should have been fine. This time around I just left the bimmer plugs in while doing my testing. I pulled the engine apart again last month, now it's ready to go back together tomorrow. We will see what happens over the next couple weeks when I put in some new 7's.

j9fd3s

iTrader: (3)

before i assemble an engine i like to put the eshaft and front pulley on, just to check the timing marks. i'm not super crazy about it, i just visually check it. ive heard too much of this s4/s5 pulley differences not too.

aside from that, just keep tuning, the e11 can be tricky because its very fast, and there are a TON of correction maps you can be using.

i think its impossible to hurt the engine around idle with no load, so feel free to play with it, although you may wanna sketch out a logical progression so you learn what the ENGINE likes. since you have it on a stand, i'd tune it up to whatever rpm you can without melting the garage....

Speed of light

iTrader: (8)

From your pics, I don't see a concern with the electrodes, per se; rather, it's what's going on with the insulator that has me concerned--looks like fouling or some sort of glazing. I experienced a similar problem with the trailing on a new engine once.

I agree with those that have suggested you should start off with plugs known to work (and go back to the BUR's later, if you insist, once everything is sorted out). The cheap Autolites do work good, just don't last forever. Or for a couple more bucks, I would start with BR7EIX and a small-ish gap.

arghx

iTrader: (3)

Yuck. I'll never run an EIX plug again. I annihilated the BR10EIX (turbo 2 rotor engine). They couldn't handle the heat and the insulator broke. I wasn't happy with the degraded idle quality either, but that's a 10 heat range plug.

Why don't you just keep OEM plugs? Ok, you will have to change them more often. So what? It's a modified engine, which means more frequent maintenance intervals. Also try the platinum plugs BUR7EQP and BUR9EQP.

t-von

iTrader: (8)

Well I'm running the trigger set-up from the Fd. I'm currently aggrivated at the moment. I got the engine back together and ready to fire back up but, I can't find my map sensor. I was doing some stuff a little while ago and needed the vacuum lineoff of it. Now I can't remember what I did with the sensor. Sad thing is, I never misplace stuff like this.

C. Ludwig

iTrader: (27)

The LS1 coils are fairly weak IMO. 4ms charge is on the low side to get a decent spark out of them. I'd run a minimum of 5ms, 6ms is what I prefer for direct-fire operation. You need to put a lot of dwell into them to get anything out of them.

t-von

iTrader: (8)

Hmmmm thx I'll make that adjustment. If the LS1 coils turn out to not be strong enough, I have access to the Yukon coils (which are suppose to be far superior). I just haven't made the change yet because I don't want to have to buy new connectors and re-fab the brackets at the moment.