help with specifications for a home made synchro

[deQuincey]

today synchro day + additional settings

today i have checked the whole thing again, and i was desperate about engine stumbling at iddle

the iddle was perfect in the figure (980 rpm´s with the air filter housing installed), but the engine was stumbling,

so i thought that i should check the distributor setting, the distributor was set according to specification with a stroboscopic lamp in the workshop

i painted a orange dot in the fixed plate (to allow me see the blue line that comes next), and a continous blue line from the plate to the distributor body to mark the "original setting position"

then i removed the securing bolt and i started rotating the distributor only a bit

i discover that anti-clockwise the engine died and started some annoying metallic noises inside the engine, the engine stumbled more and so I decided that was the bad direction

then i started moving it clockwise, i discover a clear reduction of the stumbling and a happier sound of the engine, until i turned it too much and it began dying again, so i went back a little and i left it there, as in this pic.

detail

then i checked the vacuum at iddle and this is the promising result (figure 18 "Hg = -0,6 bar) in both carbs

fantastic !

but, a question: i feel that the exhaust smoke is very hot now (sorry i don´t have a termometer), so, can the distributor advance affect the exhaust temp ? can it harm the engine ? does anybody know which is the exhaust smoke expected temp at the exhaust tail ?

regards

 

[61porsche]

Pay attention to the water temp. If it is near normal, you're done. If your water temp is a little high, slightly turn the distributer the opposite way just a bit. ( 2 degrees)

Yes, advance can effect temperature. What you're experiencing is reffered to as , "stack'. Components such as chain, sprockets, cam, piston position,distributer, points, etc. all effect the final best timing.

Looking at your blue marks, that doesn't seem too far off. Just enough to make the adjustment.

How does it feel on the road?

 

[deQuincey]

Pay attention to the water temp. If it is near normal, you're done. If your water temp is a little high, slightly turn the distributer the opposite way just a bit. ( 2 degrees)

Yes, advance can effect temperature. What you're experiencing is reffered to as , "stack'. Components such as chain, sprockets, cam, piston position,distributer, points, etc. all effect the final best timing.

Looking at your blue marks, that doesn't seem too far off. Just enough to make the adjustment.

How does it feel on the road?

hi, thanks for answering

the water temp, seemed normal (a little below the middle point), but i had not enough time to check it on the road, the temp reading is more from the iddle situation while checking everything. According to that probably the temp seems to be very good !

on the road it has been a very quick turn around the block (i was in a hurry), the car behaviour seemed very good, with nice transition from 1000 to 2000 and 3000 rpm´s, i noticed something (a little strange not linear acceleration) at 3800 rpm´s but it was a very small ride to check it in detail, ....what should i expect ?

i found that a clear improvement has taken place, just before this final adjustments, when starting my way to a sudden slope in 4th gear, the engine started a tickling sound until the revs went up and power comes to climb the slope,...well that tickling-rattling sound has disappeared now

remark: i did not mention that i checked also the vacuum at 1700 rpm´s (as the manual says, using the adequate bolt in the joint rod), and i fixed an equal vacuum in both carbs, using the knurled piece on the rear carb

regards

 

[61porsche]

Sounds pretty normal.

The 3800 rpm- might just be the secondaries on the carbs kicking in and your foot getting happy!

I assume it starts well?

Anyway, the next time is easier and faster.

 

[deQuincey]

Sounds pretty normal.

The 3800 rpm- might just be the secondaries on the carbs kicking in and your foot getting happy!

I assume it starts well?

Anyway, the next time is easier and faster.

ha, ha, ha, it starts fabulous my friend !, straight to 1400 rpm´s without a kick to the accel (provided a first kick before start has been done to properly close the butterflies)

i have to re-check it (probably this weekend), because i have a sin of defeat in this continuous trials, but i guess this time is going to be the right time !

my biggest "muchas gracias" to you for your help and excellent advises

 

[61porsche]

De nada.

Glad to hear things have improved.