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914World.com _ 914World Garage _ tune up

Posted by: cpavlenko Jul 26 2015, 09:22 AM

I usually have my tune up done by Aircooleds Only. But now on a tight budget, and I have a ?. My Haynes manual says for timing to undo vac hose to diz, and bring the rpm to 3500. y is this. Just wondering. oh, it's a stock 1.7 FI engine.

Posted by: cpavlenko Jul 26 2015, 11:46 AM

QUOTE(cpavlenko @ Jul 26 2015, 08:22 AM) *

I usually have my tune up done by Aircooleds Only. But now on a tight budget, and I have a ?. My Haynes manual says for timing to undo vac hose to diz, and bring the rpm to 3500. y is this. Just wondering. oh, it's a stock 1.7 FI engine.

bump

Posted by: brant Jul 26 2015, 11:57 AM

the advance weights in the distributor throw outward as rpm increases...
(increasing the total advance of to the motor)

so at 3500rpm they are maxed in their travel

if you time below 3500rpm, or below max advance... you are not reading an accurate number and the motor will continue to gain advance as it revs

example: if you set 29degree's of advance at idle.
you will have much more advance on the road as the car is at higher rpm
you will then have too much advance leading to pre-detonation, higher temps, poor running, and eventually a holed piston

follow the manual

Posted by: cpavlenko Jul 26 2015, 12:38 PM

QUOTE(brant @ Jul 26 2015, 10:57 AM) *

the advance weights in the distributor throw outward as rpm increases...
(increasing the total advance of to the motor)

so at 3500rpm they are maxed in their travel

if you time below 3500rpm, or below max advance... you are not reading an accurate number and the motor will continue to gain advance as it revs

example: if you set 29degree's of advance at idle.
you will have much more advance on the road as the car is at higher rpm
you will then have too much advance leading to pre-detonation, higher temps, poor running, and eventually a holed piston

follow the manual

Thanks for your input, makes sense. I'll b getting my new plugs, diz rotor, cap and plug wires Tuesday. Going to run ngk 6bes (7432 ) and time as the manual says.

Posted by: cpavlenko Jul 28 2015, 09:14 PM

Ok, I'm looking at timing hole, facing the firewall towards the front of 914. So as I'm looking towards the front, and I see tdc, is before tdc to the right or left? I hope I'm making sense.

Posted by: The Cabinetmaker Jul 29 2015, 04:18 AM

Left. Towards the drivers side

Posted by: cpavlenko Jul 29 2015, 07:10 AM

QUOTE(The Cabinetmaker @ Jul 29 2015, 03:18 AM) *

Left. Towards the drivers side

thanks.

Posted by: Elliot Cannon Jul 29 2015, 10:39 AM

3500 rpm can be a little noisy. Ear protection makes this job a lot more comfortable.


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Posted by: cpavlenko Jul 29 2015, 01:53 PM

One more ? When i remove the vac hose, do i need to plug the hose.

Posted by: BeatNavy Jul 29 2015, 03:56 PM

I believe you should (I do). This is a good read: http://www.pelicanparts.com/techarticles/914_timing/914_timing.htm
Note that it's also best to set dwell before you do timing (if you have not already).

Posted by: cpavlenko Jul 29 2015, 04:41 PM

QUOTE(BeatNavy @ Jul 29 2015, 02:56 PM) *

I believe you should (I do). This is a good read: http://www.pelicanparts.com/techarticles/914_timing/914_timing.htm
Note that it's also best to set dwell before you do timing (if you have not already).

No points, pertronik electronic ignition. Is there still a dwell setting with the pertronik? Like i said in previous post, my first time doing this because of low budget and can't afford to take to my local aircooleds only mechanics . So I'm in the learning mode with the help of 914 world. And it's great to have all the knowledge given to me by this site. pray.gif much appreciated.

Posted by: ThePaintedMan Jul 29 2015, 06:15 PM

QUOTE(cpavlenko @ Jul 29 2015, 03:53 PM) *

One more ? When i remove the vac hose, do i need to plug the hose.


If you're going by the book - yes. You need to eliminate all sources of vacuum leaks. Did I miss this - is it carbed or fuel injected? Edit: Sorry, I saw that it's FI. Plug the hose coming from the plenum.

Plug the hose wherever the source of vacuum is coming from (i.e. don't plug the distributor).

Posted by: cpavlenko Jul 29 2015, 06:26 PM

QUOTE(ThePaintedMan @ Jul 29 2015, 05:15 PM) *

QUOTE(cpavlenko @ Jul 29 2015, 03:53 PM) *

One more ? When i remove the vac hose, do i need to plug the hose.


If you're going by the book - yes. You need to eliminate all sources of vacuum leaks. Did I miss this - is it carbed or fuel injected?

Plug the hose wherever the source of vacuum is coming from (i.e. don't plug the distributor).

Stock 1971, 1.7 fuel injected engine.

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