4g32GS ?

[shuggy]

whats a 4g32gs?

[75wagon]

whats a 4g32gs?

That's the motor my carbs came on.
They weren't available here in Australia.
I can paste up a few pages with the comparison specs between the standard Saturn and the Saturn GS if you like?

Dave...

[shuggy]

i have almost every manual - which one would i fint the specs in? if compression and dizzy timing are different it may be good to give those specs to RPW when i get my 4g32 rebuilt - may need different pistons..

[75wagon]

This book.
It looks a bit tattered now
It has the only printed material I've ever seen on the Solex twin downdraught set up...
Has all the GS specs. To me it's like the bible of the Galant workings.

[Torana68]

i have almost every manual - which one would i fint the specs in? if compression and dizzy timing are different it may be good to give those specs to RPW when i get my 4g32 rebuilt - may need different pistons..

snuggy, the dist it set for leaded petrol so the settings are no good, nor is the timing, you cant get High Comp pistons so no point worrying about that just let the guys at RPW sort it.....

[shuggy]

i have 2 of them

wow never knew what the GS was.

looking at a few of the facts,

overall dimensions of engine LxHxW (4g32/33 606x654x645 vs 4g32gs 606x597x605)
the cam timing is different (in 20 - 48 out 51 - 17 versus in 24 - 64, out 67 - 21 (gs))
different plugs (bp-5es vs bp-6es)
timing is way different (5 degrees @ 700rpm vs 13 @ 800)
minimum fuel consumption (minimum @ 3000rpm vs minimum @ 4000)
compression ratio (8.5 vs 9.5:1) and 4g33 is 9.0:1 (10.5kg/cm 149psi VS 11.5kg/cm 163psi @250rpm)
stronger springs in the head
the GS pistons arent dished

and apparantly differnt 4 speed gearbox ratios overseas

thoughts if its possible to get a standard 4g32 up to this spec?

i know the pistons arent as dished

[toruhiwi]

It's the octane rating which makes a difference, not wheather it's leaded or unleaded.

If you use Premium ULP, preferrably 98octane, you can increase the initial timing accordingly. Try it on about 15degrees BTDC initially. If it pings under load, knock it back 2 degrees at a time with road testing. You should be able to get at least 10 degrees. If you have carboned up combustion chambers this will affect it......With a GS cam, which has more duration, you can usually get at least 15 degrees.

Use BP7EY plugs ( it may missfire for a minute after first start-up in very cold weather) These colder plugs will keep combustion temp down to overcome the tendency to ping. Make sure the distributor vacuum and mechanical advance are working correctly, otherwise you are wasting your time.

Don't use BP5ES or BP5EY plugs in any Mitsubishis unless you live in a sub-zero climate. I am a mechanic and have serviced many Mitsus for many years and have never used that heat range, mostly use BP6EY.

No two engines are the same, so they need to be tuned accordingly, and that goes for ignition as well as carby set-up.

Shuggy, are yours chain drive or belt drive?

Roger

[shuggy]

i have chain drive mate, and currently having to run 98 and still pinging a tiny bit around. 2500 rpm under load..

[shuggy]

what the hell am i talkin about. I have belt. Im going to rebuild a chain for my next car thats the one i was looking at increasing compression in..

[toruhiwi]

Shuggy,

What initial timing have you set in the chain drive? .....Is the distributor working properly??

Which plugs are you using?

Roger

[81GL]

These colder plugs will keep combustion temp down to overcome the tendency to ping

The heat "range" of a plug doesn't effect combustion temp. Unless your way off the ball park and the plug melts
Just use the standard plug, it will be fine.

Nick.

PS: There are differences in the timing between leaded and unleaded set ups, as well as a few other things.

[shuggy]

in my current belt set up..
i have no idea

i dont have a timing light so i havnt bothered fidling around with it, i got the engine out of a FWD 87' colt and it was rebuilt 20000 clicks before that so im really unsure hey, but on 91 unleaded its a reallll bitch..

[shuggy]

ok..
according to HERE http://www.piston.com.tw/cht/upload_fil ... ubishi.pdf the 4g32gs pistons are the same as g32b pistons..
comments?

here are the piston head shapes
http://piston.com.tw/products/piston-he ... 21-140.htm
the 4g32gs and g32b are both #123..

think this is right?

[shuggy]

"the 165 horsepower racing saturn"

http://translate.google.com/translate?j ... l=ja&tl=en

[Torana68]

you may have noticed different Mits part numbers, they are different for a reason

[davetrees]

i have chain drive mate, and currently having to run 98 and still pinging a tiny bit around. 2500 rpm under load..

Unless you are running very high compression. if it's pinging on 98 it's seriously in need of a tune !

The 4G32GS-spec engine is also what was in the 1600GSR Lancer - higher compression, different cam (#2 or #3 ?), different distributor advance curve, twin downdraughts.

All being well, I will shortly be the owner of 2 of these motors, courtesy of a recent "shed find"

[toruhiwi]

These colder plugs will keep combustion temp down to overcome the tendency to ping

The heat "range" of a plug doesn't effect combustion temp. Unless your way off the ball park and the plug melts
Just use the standard plug, it will be fine.

Nick.

Sorry, but you are wrong!!!

[81GL]

These colder plugs will keep combustion temp down to overcome the tendency to ping

The heat "range" of a plug doesn't effect combustion temp. Unless your way off the ball park and the plug melts
Just use the standard plug, it will be fine.

Nick.

Sorry, but you are wrong!!!

Always willing to listen, care to explain?

[Superscan811]

Here are some specs.








Cheers.

[toruhiwi]

This explains it very well...................

http://www.ngksparkplugs.com/tech_suppo ... p?mode=nml

Roger

[SE Wagon]

Yes, that does explain it very well. It explains that this is wrong:

These colder plugs will keep combustion temp down to overcome the tendency to ping.

You have cause and effect mixed up. Pinging causes elevated combustion temperatures; the pinging is caused by the spark plug becoming too hot. If the spark plug doesn't get too hot there won't be an appreciable difference in combustion temperatures between plugs.

The spark plug is heated by combustion. The design of the spark plug determines how easily the plug absorbs heat, and how easily it dissipates heat. This is why different plugs have different "heat ranges" - and it has nothing to do with causing combustion temperature changes.

The relationship is the opposite to what's been described in the quoted bit.

Low combustion temperatures require a "hotter" plug, to ensure the plug operates in the correct temperature range. Changing to a "hotter" plug doesn't increase the combustion temperature; the "hotter" plug absorbs more heat, dissipates less and runs "hotter".

Higher combustion temperatures require a "colder" plug, to again ensure the correct temperature range of the plug. Changing to a "colder" plug doesn't lower the combustion temperature; the plug absorbs less heat, and dissipates it more easily, so it runs cooler.

If the plug runs too cold, it fouls. A hotter plug is needed, or drive harder. If the plug runs to hot, it can cause the mixture to ignite before the spark - pre-ignition, exactly as if the ignition was too far advanced.

Changing the plug isn't changing the combustion temperature. It's all in the link posted by Roger.

[toruhiwi]

This is on page 2............how would you inerpret it?

"The most serious result of selecting a heat range that is too hot is overheating. Overheating will cause the electrodes to wear quickly and can lead to pre-ignition. Pre-ignition occurs when the air-fuel mixture is ignited by a hot object/area in the combustion chamber before the timed spark event occurs. When the spark plug firing end (tip) temperature exceeds 800°C, pre-ignition originating from the overheated insulator ceramic can occur. Pre-ignition will dramatically raise the cylinder temperature and pressure and can cause serious and expensive engine damage."


Roger

[Superscan811]

.how would you inerpret it?

As Very bad..
Pre-ignition/pinging/detonation/etc.. all cause major problems/damage for the engine, especially if they aren't quickly rectified.

Cheers.

[toruhiwi]

Yes, that does explain it very well. It explains that this is wrong:

These colder plugs will keep combustion temp down to overcome the tendency to ping.

Thanks for that, but the extract was for the benefit of "SE Wagon" and "81GL".........................I hope they read and understand it fully.

Roger

[webby]

Sorry mate, but I'm with SE Wagon and Nick on this one. The second page of that article clearly states that detonation causes higher combustion temps, not the plugs.
Sure, the wrong heat range plug can cause the detonation, but so can having the timing too far advanced and running too low an octane fuel for your current tune. The plugs themselves aren't the direct cause of the higher temps.

[shuggy]

i have chain drive mate, and currently having to run 98 and still pinging a tiny bit around. 2500 rpm under load..

Unless you are running very high compression. if it's pinging on 98 it's seriously in need of a tune !

The 4G32GS-spec engine is also what was in the 1600GSR Lancer - higher compression, different cam (#2 or #3 ?), different distributor advance curve, twin downdraughts.

All being well, I will shortly be the owner of 2 of these motors, courtesy of a recent "shed find"

oh really.. you have to take off the head and have a look for me

[SE Wagon]

This is on page 2............how would you inerpret it?

"The most serious result of selecting a heat range that is too hot is overheating. Overheating will cause the electrodes to wear quickly and can lead to pre-ignition. Pre-ignition occurs when the air-fuel mixture is ignited by a hot object/area in the combustion chamber before the timed spark event occurs. When the spark plug firing end (tip) temperature exceeds 800°C, pre-ignition originating from the overheated insulator ceramic can occur. Pre-ignition will dramatically raise the cylinder temperature and pressure and can cause serious and expensive engine damage."


Roger

The "overheating" comment in the first sentence is referring to the plug - the plug overheats, not the cylinder. Once detonation starts, THEN the cylinder overheats.

Without the pre-ignition, there isn't an appreciable change in combustion temperatures.

Go back and read all five pages of your link again. As you posted, it is explains it very well.

[toruhiwi]

And it clearly states that a HOT AREA, (and this INCLUDES an overheated plug ceramic, CAUSED by a too hotter plug) is one of the causes of preignition, which in turn raises temperature.

Lets understand that a too hotter plug is ONE of SEVERAL causes of preignition etc etc...........and I never intended to indicate otherwise.

Pinging can OFTEN be overcome by fitting a colder plug, and we can't see inside the cylinder wheather it's the too hotter plug or a carbon hotspot causing it, but we usually have a good idea about lean mixture, advanced timing etc.

If all the other parameters are met, we can usually make a few more degrees on spark advance in most of these early Mitsubishi engines by fitting a colder plug tis what I meant..........and I believe we are attempting to get the best performance we can out of what we have. Fit BP7ES plugs to your 4G32 and adjust/advance the timing in 2 degree increments by road testing or better still on a dyno and you will see what I mean. Then refit your BP6ES and listen to it. The 4G32GS specs the "7s" and a much increased initial advance than the std engine, partly helped admittedly, by increased overlap of the valve timing (in the chain drive version). This overlap reduces combustion pressure hence temperature. (Most of the local 4G32 Belt Drive originally have the #6 GS cam anyway) I owned an early L300 1.6 for many years, used BP7ES and around 12degrees on what was 95 octane.

Maybe I didn't explain my thoughts fully in the first instance and could have said ..."to "help" keep the combustion temp down............"because of this increase in spark advance""
Incidently, I know what the various causes are, I learnt that when I was an apprentice over 40 years ago.

PS
The main problem here seems to be that the quoted sentence (by 81GL) was a very small part of my original post, and was out of context with what I wrote.
If you read the whole post you will find that I was referring to increased spark advance ONLY, in regard to using colder plugs.

I certainly didn't convey the idea that pinging from whatever cause could be remedied by using colder plugs...............quite the opposite I would have thought.

[shuggy]

should i change the name of the topic to world wide spark plug debate?

[toruhiwi]

Was thinking the same...........................

Started off trying to help others to get the most out of their Saturn............oh well

Roger