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Discussion Starter · #1 ·
Here are the results from a 2nd through 5th pull with the LM-1 and rpm converter.

Also at cruising speeds in fifth and sixth I am seeing numbers in the low 11's, seems pretty rich to me, but mabye my cam needs it. Here are me engine specs.
385 stroker, forged eagle rotating assembly, probe flat top pistons, canfield 195cc heads, howard solid roller cam 258 intake, 268 exhaust at .050, 605 lift intake, 605 lift exhaust, gear drive, msd 6al, msd timing retarder, msd window switch, 100 shot nitrous, victor jr. intake, topped off with a 750 race demon general competition. It has a mcloed dual disc clutch backed by a richmond 6 speed transmission.

Sorry if my attachment does not open. You might have to have the lm-1 software on your computer. Let me know and I will just post some of the numbers. Thanks.:thumbsup:
 

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You can NOT post the LM-1 plots without the LM-1 program downloaded onto you computer.
You should idle in the high 12's low 13's and cruise in the high 13's and low 14's. WOT in the 12.5 range and nothing in the 11's unless you are supercharged.
I reworked the transfer slots by jetting them so I idle in the high 12's and drop into the 15-16's for cruise.
Best power is at 13.2, best fuel economy around 15.4
You need vacuum advance to run these lean mixtures.
You can not burn a motor up with lean cruising and only at WOT does lean apply. That is the only time you can not run lean mixtures and must be around 12.5
Fuel does NOT cool the motor. It retarts detonation, nothing to do with cooling. Detonation is the enemy of motors but it only happens under high throttle conditions and lean mixtures.
Under light cruise even 14.7 that new cars run is not considered lean. I have burned mixtures at 16 and 17.
I would love to see a plot. I have the LM-1 software.
 

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Discussion Starter · #3 ·
I thought I attached it, I will try again.
It sais it is an invalid file, give me your e-mail and I will send it to you. Or go onto innovate's web site and I posted it on there under the same title. I am looking forward for you input.:thumbsup:
 

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I just purchased an LM-1, but have not installed it yet. I look forward to hearing more about your tunning experiences.

Good Luck!!!
Chris
 

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I thought I attached it, I will try again.
It sais it is an invalid file, give me your e-mail and I will send it to you. Or go onto innovate's web site and I posted it on there under the same title. I am looking forward for you input.:thumbsup:
Post the link. I just went to the LM-1 forum and didn't see it?
 

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Discussion Starter · #6 ·

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It worked fine. That is the only forum I know that I can post plots.
If you are WOT you are too lean. At WOT you should read about 12.5 consistantly.
I am more into cruise tuning and your plot at the bottom is just too small to see anything.
YOu can NOT run really lean and well without vacuum advance. No one should run a street machine without it. NO ONE
For cruise get on a nice quiet road and just start recording at a steady 60 mph our so and let it run for 5 minutes and then post the plot.
I jet the transfer ports, this is becomming more common but I jet for a steady state with vacuum advance for about 16-1 or even 17-1
You can not run a part throttle motor too lean. Can't hurt it. Lots of advance , about 52 degrees and lean as the motor will take.
You need to set the idle in the high 12's or low 13's for good idle but that is also your super rich cruise mixture so I again jet the transfer ports to accomplish this.
Best horsepower is at 13.2 but a total waste of fuel. Best ecomony at 15.4 but agian you can run leaner. New cars choose 14.7 as a compromise.
Do not run a power valve in the secondaries. Jet accordingly but keep the power valve in the primaries, drill the power valve in the metering block to .070 and consider jeting the transfer slots.
I played with the 4 air bleeds as well but just set them to a fixed value of .075 and .026
 

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Discussion Starter · #10 ·
I am more into cruise tuning and your plot at the bottom is just too small to see anything.
I will post a cruise plot after I finish this, it will be a fifth and sixth cruise. I am not sure if I understand, it is too small to see, you can click on the magnify promt and click on the timeline at the bottom to stretch out the plot?

YOu can NOT run really lean and well without vacuum advance. No one should run a street machine without it. NO ONE
How do you run a vacuum advance, I am not familiar?

[I jet the transfer ports, this is becomming more common but I jet for a steady state with vacuum advance for about 16-1 or even 17-1
/QUOTE]
This is all new to me and I really appreciate you time and patience. Where can I find the info on the break down of the carb, so I can figure out how to change these things.

You need to set the idle in the high 12's or low 13's for good idle but that is also your super rich cruise mixture so I again jet the transfer ports to accomplish this
I idle in the 14's at about 750 rpms and it sounds good. I get fumed out so I fiqured that was still rich. If I idled in the 12's wouldn't that be too rich.

Best horsepower is at 13.2 but a total waste of fuel
I am not worried about fuel, I don't put over 1000 miles on it in a year. I just want the most power without hurting my motor. I want to be able to use my 100 shot of nos and not melt a piston. I probably been through 6 bottles before the LM-1 with no problems that I am aware of. The only way I was tuning before was listining for detonation and checking plugs. By the way I am using a autolite 3924 racing plug.

[Do not run a power valve in the secondaries. Jet accordingly but keep the power valve in the primaries, drill the power valve in the metering block to .070 and consider jeting the transfer slots.
/QUOTE]

How do I know if I am running a power valve in the secondaries. I thought my carb does, it opens up to dump fuel in when the jets in the transfer slots are overwhelmed, right?

Thanks,
Rob
 

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It worked fine. That is the only forum I know that I can post plots........
In future you may want to try this free site. You upload any file extension up to 300mb/file and post links for unlimited downloads. Copy and paste the download link after you upload.

http://www.filesend.net/

Great for file extensions most hosts don't allow including exe files that most email servers don't allow. :thumbsup:

Now back to the scheduled program.:laughing: :laughing:
 

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Vacuum advance is part of the distributor. You need a rubber line running from you intake to the distributor and yes I like vacuum off the intake and not off the carb port. Off the intake it works as soon as the car is started and helps idle quality. Port vacuum only starts after you start driving and is no aid to idle. You can not get best gas mileage without vacuum advance and again ALL street cars should have one. It does not affect top end running.
As for wasting gas and only driving 1000 miles a year? Wasted gas translates into wahed rings, shorten engine life, fouled plugs, carboned valves, poor running caracteristics and just a waste.
A clean running motor is more ecomonical to run, lasts alot longer and stays health.
Daytona cars use to but not anymore, it is illegal but they would jet leaner, run hotter and more advance for qualifying engines since they put out more power and then switch back to a more conservative setup for longevity at WOT
 

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Power valves. You need one in your primary for getting you from cruise to the main jets, passing, hills or anytime you call on the motor with light throttle.
The number on the power valve affects when it opens but the drilled ports under the valve meter the amount of fuel you are getting. These are often too small, in the .05s range and they should be .070 minimum and can go to the high .07s but only with trial and error. .070 is safe for the first drill. These pass fuel to aid the main jets.
As for a secondary power valve if you secondaries are open you are asking for maximum effort so forget the secondary power valve and go directly to the jetting. Jet about 6 sizes bigger if you pull the secondary power valve. I run plugs in mine.
Plugs under normal driving conditions Should look lean, white is fine. People talk about reading plugs, this is under race conditons with a clean cut off of the ignition. I check plugs all the time but I am looking for the clean, white, new looking plug that I putt around on all the time. Pull a plug after cruising and idling into the garage and it is a nice deep tan and you are too rich for what you are doing..
I honestly upped my mileage per tank around town by 25-50% and the car never ran better.
 

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Discussion Starter · #14 ·
So by doing this I will be able to richen my idle, lean out my cruise and richen my wide open throttle, correct?

If my distributor does not have vacuum advance now can it be added?
 

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So by doing this I will be able to richen my idle, lean out my cruise and richen my wide open throttle, correct?

If my distributor does not have vacuum advance now can it be added?
I thought I needed it enough that I went out and spent $350 for the same distributor that had vacuum advance. I ran without for 30-40 years and only resently learned that I was stupid for not running one.
Without you are compromising, running a retarted ignition everywhere accept at WOT.
Why have a motor and drivetrain tuned to perfection for WOT and then put around on the street 99.9% of time.
In the 60's I ran around with 456 gears, cams that wouldn't idle 12.5 compression etc etc and today I could effortlessly outrun even my low 10 second street machine. One that doubles the gas mileage and cruises with highway friendly gears.
I for one am glad they don't build them like they use to.:thumbsup:
 

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a kinder gentlier Mad Max!....winning the hearts and minds of law enforcement everywhere.:D
Nothing to do with law enforcement. Our cars today are faster then they ever were. Get better mileage. Don't have to compromise gearing and expressway driving. less polution as well.
I had a 10.2 second ride back in the early 70's and it was a pain on the open road. I am sure my present ride would have no problems with times like that with a little tuning and slicks and yet on the open road I cruise at 100 mph effortlessly and pull down really great mileage.
Today our cars are smoother and faster then ever before.
 

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Nothing to do with law enforcement. Our cars today are faster then they ever were. Get better mileage. Don't have to compromise gearing and expressway driving. less polution as well.
I had a 10.2 second ride back in the early 70's and it was a pain on the open road. I am sure my present ride would have no problems with times like that with a little tuning and slicks and yet on the open road I cruise at 100 mph effortlessly and pull down really great mileage.
Today our cars are smoother and faster then ever before.
Yeh, I hear you, thing is....they all look alike....seen that style...design something NEW now, for Christsakes.....pull the badges and can't tell one from another...take tha names off the valve covers, EPA markings...can't tell one from another either.....now many ways can they make a 2.0 4 banger with auto and air???

:devil: :devil: :rolling: :WTF :cheers:
 

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Discussion Starter · #19 ·
I thought I needed it enough that I went out and spent $350 for the same distributor that had vacuum advance. I ran without for 30-40 years and only resently learned that I was stupid for not running one.
Without you are compromising, running a retarted ignition everywhere accept at WOT.
I don't know how much this matters but I run 34 degrees overall timing, that comes in at 2000 rpms. My initial is around 18 degrees. I would like more but with my msd I can't without making my own bushing, which I have not done. Barry Grant recommends running 24 degrees for my initial timing and my engine builder recommened 34 for overall. It idles better with more initial, but overall my throttle response is very crisp.
 

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I run 24 initial, 12 with mechanical for 36 all in by 3000 and 16 vacuum advance for 52 total.
At idle I have the 24 plus 16 or 40 degrees idle.
Your ignition is retarted for everything except WOT and how much do you run flat out?? 99% of the time your car is not at WOT so why run around with a retart.
Vacuum advance is zero at WOT so it doesn't hurt performance. If a mechanic tells you you don't need a vacuum advance he is not really in the know.
What is a mechanic anyway?? Most just take the required coarses and replace parts after that. Then some learn, understand and know what they are saying. Which one do you have???
 
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