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Mon Aug 26, 2019 2:39 pm

There are three problems when my idle is set at 7-800.

It's harder to get going from a stop.
Oil light is on.
It wants to die when crawling across a bumpy trail.

Why can't I just set it to 1000?

Mon Aug 26, 2019 2:58 pm

A few things; if you are having trouble with an idle set at ~800 rpm, your engine is telling you something.

What engine is in it?

What type of car?

Stock or modified?

Carburetor type?

Distributor type?

As for the oil light, you may want to install an oil pressure test gauge and actually measure the oil pressure. It could be as simple as a pressure switch for the oil light going bad, but if you actually have low oil pressure, that is a problem.

Mon Aug 26, 2019 3:39 pm

Yes you can set the idle at 1000 RPM's and the Earth will not stop rotating. There is no fucking law that say you must set your idle 700-800 RPM. The ONLY thing that will happen if you set the idle at 1000 RPM is you will use a very tiny bit more gasoline when the engine is running.

I suggest anybody with dual valve springs set their idle at least 900 RPM so the dual springs get enough oiling.

Mon Aug 26, 2019 3:51 pm

vwracerdave wrote: Yes you can set the idle at 1000 RPM's and the Earth will not stop rotating. There is no fucking law that say you must set your idle 700-800 RPM. The ONLY thing that will happen if you set the idle at 1000 RPM is you will use a very tiny bit more gasoline when the engine is running.

I suggest anybody with dual valve springs set their idle at least 900 RPM so the dual springs get enough oiling.

While I agree that it’s fine to set idle at 1000 rpm, my point is that, assuming it is stock or fairly stock, it should have no trouble idling where the factory set it, and if it’s experiencing problems being set there, then setting it at 1000 might just be masking some symptoms.

Regardless, the oil pressure should be checked.

Mon Aug 26, 2019 4:27 pm

There is the ideal and then there is what you can deal with.

Mon Aug 26, 2019 5:15 pm

My rebuilt 36hp would idle at 300 rpm. Not recommended, just an exercise to see how low can you go.

1000 shouldn't be required other than for an older engine and auto tranny. So more info is better here.

Mon Aug 26, 2019 6:07 pm

900 to 1000 -- lower is not better or good for the engine. Oil pressure, battery charging especially if a generator.

Mon Aug 26, 2019 6:48 pm

If you have a stock carb or probably any carb for that matter the low idle is needed to adjust the Lean Best Idle. If the throttle plate is open too far you will be trying to adjust the carb on the progression ports.

So set the idle at 750 or so....get the carb adjusted ...then set idle where you like it.

I prefer my idle at 900-1100 rpm....it makes take offs much easier and then my cold idle is a little faster......I do have Fuel Injection though.

When I use thin oil my oil pressure is low when it's hotter out so a faster idle keeps the pressure up a little.

Tue Aug 27, 2019 6:14 am

I agree with Paul. What are your engine specs? Carb and Distributor, Timing?

If you have a high performance engine then yes, 1000rpm is ok if it's a stock or basically stock engine, then you have problems you are just masking.

Even my race engine will idle at 850rpm

brad

Tue Aug 27, 2019 7:24 am

Still have not heard from the Poster about his engine.
1000 RPM is not a bad thing as the fan will blow more air for cooling.
Tell us all about the engine please.

What engine is in it? What type of car? Stock or modified? Carburetor type?
Distributor type?

Tue Aug 27, 2019 7:24 am

Potentially stupid question: are you sure it's the oil light and not the generator light? Because if it is the gen light, it is common for the light to come on a bit when the idle is the normal 800 rpm.

Tue Aug 27, 2019 8:12 am

OP here. Thanks for all of the suggestions. I like the easy answer which seems to be "Yes, 1000 is OK", but since this topic has generated so much interest I've listed the specs below my short summary of the engine.
I just recently bought this car. I am not an engine mechanic, but can turn a wrench.

Engine was built for torque in about 2005 for a VW bus, then put in a 1973 bug in 2008 or so. Motor was revised for highway use with dual carbs, different heads, etc.
Build thread here: https://www.thesamba.com/vw/forum/viewtopic.php?t=335057&highlight=another+class
2006 cc engine has about 80,000 miles on it. Runs strong on highway, even at 11,000 feet, but has no low end torque.
Oil pressure guage shows 28 warmed up and cruising on hwy at 3500 RPM on a hot day. OP at idle when hot is about 6 thus light comes on.
Oil is 5W-30 dino. Car runs cool with sump, external filter, external oil cooler. Full flow oil system.

Specs as I understand them to be. (my comments in parentheses)

Steve Tims Stage 1 Plus heads (per his ad - Ideal torque head for stroker street and off road engines )
42x37 valves, hi-rev springs, swivel feet, solid shafts, 1.25 rockers.
(Alt info says Empi solid shaft rockers with swivel adj., 1.25 was crossed out)
Aircooled.net’s heavy duty aluminum push rods
90.5 Mahle pistons, B stroke, Teflon buttons
CB Performance cromoly rods
Scat counter-weighted crank (78mm)
Stock weight flywheel, 8 dowel w/ Scat gland nut
Balanced rotating assembly
Engle 110 cam (a samba post says an Engle 110 cam has 383 lift at cam. 236 duration at 0.050 range 3500-5000) See exhaust.doc
8.5:1 compression
009 with Compufire (next owner may have changed this). 2011 build photo showed Dist with vacuum adv, now w/o.
(Rob said it had a SVDA on it when he sold it.)
Plugs NGK B7ES maybe
Weber 44 IDF’s, made in Spain (completely rebuilt with Jet Dr’s hardware, etc)
(Robb said carbs are running rich at sea level)
On 4-22-2011 with dual carbs Robb claimed: 36 venturis, 50 idle, 145 main, (200 air corrector jet)
(Jets have since been change for 5000 elevation, plus carbs tuned by a VW shop)

Thanks again

Tue Aug 27, 2019 8:32 am

Those oil pressure measurements are near the minimum specs. Personally, I would like to see closer to 35-40 psi @3500, but as long as you know you have at least 6 at idle, you can live with a flickering oil light.

As for taking off better from a stop, that is most likely because of the 009 distributor. Setting the idle at 1000 rpm puts you closer to when it starts advancing.

I would say leave the idle at 1000 rpm.

Tue Aug 27, 2019 9:05 am

scottyrocks wrote: Potentially stupid question: are you sure it's the oil light and not the generator light? Because if it is the gen light, it is common for the light to come on a bit when the idle is the normal 800 rpm.
No, it is not common ... it indicates a problem with the charging system. Where do you people get this stuff? :roll:

Tue Aug 27, 2019 9:32 am

Q-Dog wrote: scottyrocks wrote: Potentially stupid question: are you sure it's the oil light and not the generator light? Because if it is the gen light, it is common for the light to come on a bit when the idle is the normal 800 rpm.
No, it is not common ... it indicates a problem with the charging system. Where do you people get this stuff? :roll:

In defense of scottydog, I think his question is legit. He was just wondering whether I was confusing the generator light with the oil light.

Tue Aug 27, 2019 9:33 am

My generator light used to flicker on when at idle. Tho it never caused any real problem, I switched to an alternator. That "problem" is gone. Also, my 009 is advanced a bit already at ~700rpm idle (compared to static timing). Here's its "curve"...

Static - 7° BTDC
Idle - 9° BTDC
3 K - 31° BTDC

Tue Aug 27, 2019 10:06 am

Q-Dog wrote: scottyrocks wrote: Potentially stupid question: are you sure it's the oil light and not the generator light? Because if it is the gen light, it is common for the light to come on a bit when the idle is the normal 800 rpm.
No, it is not common ... it indicates a problem with the charging system. Where do you people get this stuff? :roll:

I didn't say it was right. I just said it was common, judging by the many times I've read/heard about it.

sidehill wrote: In defense of scottydog, I think his question is legit. He was just wondering whether I was confusing the generator light with the oil light.

Thank you. The question was to avoid the possibility of dash light confusion.

Tue Aug 27, 2019 1:15 pm

IT's not the 009 causing the bog of idle, I can idle away from a light and roll into it gently and smoothly with every 009 distributered car I've ever owned.

Your heads are a bit big for your displacement, at idle you are going to have very low air speed with those ports, so your idle has to be bumped up accommodate. That's also going to affect your off idle performance and cause your bog on acceleration. Probably pulls good once you get some rpm in it.

brad

Tue Aug 27, 2019 3:06 pm

In my opinion, the 009 isn’t helping, but you are right. 42mm intake valves, along with 44 IDFs and 36mm venturis is probably killing low speed air velocity. Might have to live with a soggy low end if you want it to still rev the way it does now.

Tue Aug 27, 2019 3:32 pm

vwracerdave wrote: Yes you can set the idle at 1000 RPM's and the Earth will not stop rotating. There is no fucking law that say you must set your idle 700-800 RPM. The ONLY thing that will happen if you set the idle at 1000 RPM is you will use a very tiny bit more gasoline when the engine is running.

I agree with this as well.