Ive got a 22R with a weber 38, trd stage 2 cam, and full 2 1/4 exhaust. Recently i have been adjusting the ignition timing more advanced, and I am wondering if anyone has any recommendations on how far to advance it. Right now I moved it from 5 to 9deg (I think...its between the last 2 ridges on the timing tag) and havent had any problems. Will doing this affect longevity of the engine? Also, would it be a good idea to re-tune the carb after changing the timing settings, and can advancing the timing help improve gas mileage? Currently i am getting v-8ish gas mileage and i think it may be running a bit rich. Any input would be greatly appreciated.

btw there is no longer any EGR system in place.

 

you're running a 38 weber, that'll be the majority of your gas mileage issues.

the older 20R engines that had points in the mid 70s had a knob to fine tune the timing on the distributor. the procedure was to get going about 25mph, put it into 4th gear, and mash the pedal, advance it until it pings then back it off until it won't ping when you floor it. same procedure should work for an electronic 20R or 22R distributor, they just don't have the convenient knob.

 

Thanks for the reply!
Ill try and give the road test a shot sometime soon. How much timing would be typical/too much? Its already almost to the end of the tag and it seems to be driving just fine. Will advancing the timing like this be harmful to the engine in any way (as long as it doesnt ping of course)? Any other tuning advice would be greatly appreciated, my engines got some good parts that should complement each other, i just need to get it tuned in right.

 

generally it's pretty safe to go until you don't notice any more power without pinging. might make it run a little hotter with too much advance, but you'd probably notice on the gauge. before i had a timing light, i timed my 22R i built by ear, and was wondering why i'd get some intermittent pinging under heavy acceleration. bought a timing light, and found out i was about 15* advanced at idle! i run mine at about 8*, but i'm going to experiment a little more.

a big help with weber carbs is an aftermarket ignition box and coil, along with a good set of plug wires. lets you open to a wide gap(somewhere in the neighborhood of .045-.055", which will burn more of that rich mix from the weber. also helps on inclines, as it'll tolerate more fuel without stalling.

 

How are the OEM plug wires in terms of quality? Ive got a fairly new OEM cap, rotor, and wires and I havent had any problems yet with the stock ignition setup. With my current setup, would an aftermarket ignition system make that much of a difference powerwise? From what ive heard, ignition systems typically dont have very good bang for the buck.

Also, how would you recommend tuning the weber? Ive searched the internet and have found and tried the typical tuning instructions for these carbs, but i am unsure if i should be tuning each barrel one at a time or both at the same time in the same increments.

 

with a 38, both barrels open at the same time, so tune accordingly -- change your idle and main jets in pairs, using the same number. the 32/36 is a bit trickier, i still haven't figured it out all the way(i should invest in a wide band O2 sensor and gauge).

the factory wires are pretty good, but they are designed for a stock configuration. i'm using a set of 8mm taylor spiro-pro wires, and i really like them. they only cost something like $25 out of summit racing if i'm not mistaken. an aftermarket ignition system won't make much of a power difference, it's more of a drivability thing -- easier starting, and less stalling on inclines.

 

i used to have to do that to my 510. mmm electronic ignition