12a_rx7

Hey everyone. I just completed my MSD dfis with 3 blaster2 coils. I love the mod. Just wondering if it's safe for me to advance the timing. I read some where on a Racing Beat catalog that advancing the timing on stock port is not recomended. But I also read on Yawpower that 12A's make the most power with a 8 degree timing split. What do you guys recomend for timing, leading and trailing? Advance it or leave it alone. Any help would be greatly appreciated. Oh i still have the stock nikki carb.

Thanks
-Ronald

gmanuser

it depends on what you want, if you want more power at low rpm range make your timing retarted, and if you want more power at high rpm make your timing advance, i am not exactly sure about your question tho but just some advice, racing beat usually knows exactly what they are doing, the guy that owns it has been working on rotarys since before i was born so i would highly recomend taking his advice if you are planing on racing it.

cdrad51

First time I hear about this datum. Where did you you get it from?

Bass

I've been running 24 leading and 16 trailing for the past several years. It rumbles a little at idle but snaps through the high end of the tach with losts of power.

12a_rx7

losts of power???...here's some pics

Racing Beat pulley

3 coils

engine shot




Any other suggestions??

peejay

Pulled from his ***, apparently.

I have locked timing, run 22 degrees leading and I forget what trailing all the time, plus the vacuum advance is hooked up for good part-throttle economy.

It pulls at *any* RPM. The difference in the 2000-3000rpm range is *dramatic*. The stock mechanical advance isn't all in until 4000...

On the last road trip I knocked down 30 miles per US gallon, *with* sticky tires on the front, fat by huge tires on the back, and 4.78 gears...

Driving around town I upshift at 2000, maybe 2500rpm max. No need for more than that. I have normal-diameter tires on the rear now, with no degradation in fuel economy, and it's a little better in the city because it's even easier to start off in 2nd gear, so that's one less shift to have to do.

Bass

oops...that was a typo. I meant "lots".

chedda_j

hey, did you lock the timing by taking it apart and tack welding the two parts together? I thought that only worked good on turbo apps. I only get like 25mpg and i have stockers. I want to lock the timing but you know...i was told not to.

peejay

Do a search, I'm the guy telling people that there is no nada zip reason to weld anything, just carefully remove the springs, reassemble, and you're done.

I don't know why the turbo guys lock out the mechanical advance. They lock it to 10 degrees or even TDC which might be acceptable under high boost but it sucks any other time. And given that they're taking their socks off to take a **** by welding the distributor, there are easier ways of getting reduced timing under boost...

The downside to having so much advance at low RPM is that idle quality isn't so good. Not cool like most rotaries, just generally stumbly every now and then. Emissions takes a dive, too. (There was a 100ppm HC difference between 2BDTC and 5ATDC for leading, I'd hate to see what 22bdtc would be!) This is why I strongly recommend being extra super special careful removing the easily-destroyed springs in case you have to put them back in.