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-   -   milky oil with rons Terminator (https://www.racingjunk.com/forums/showthread.php?t=19806)

talgregory 02-09-2008 04:17 PM

milky oil with rons Terminator
 
i have 388 chevy .with the terminator with a 01/2 fuel pump i have the b.v. set at 17% with a 76 return jet with a 33 nozel jet . also have a vacuum pump on the eng .

thanks tal gregory :?:

johnracer 02-09-2008 06:56 PM

There are many others here with more alcohol experience than I have, but I'd start by leaning the barrel valve as far as possible and still take throttle.
Based on my very limited Terminator experience, the whole setup sounds too rich unless you have a very snotty 388. My 406 had an O pump, and ran best with 29 nozzle jets and an 88 pill at high altitude. Best et in a 2850lb 72 Chevelle was 10.28 @ 132mph in 8000 ft air.

It might be best to contact Ron's about your setup....

davis419b 02-13-2008 05:01 AM

I would say your barrel valve is too lean and your main jet is too big!

johnracer 02-13-2008 05:50 AM

How would that milk the oil? Educate me please....

OneBadGMC 02-13-2008 08:04 AM

The main jet would have to be too small, not too big, to milk the oil.

The explanation of Injected alky could go on for hours. Like I've posted in other threads, Bob Szabo (www.racecarbook.com) has a FANTASTIC book (80.00) on Fuel Injection that newcomers and 'experts' alike will find tons of information useful.

It includes ALL of the calculations needed to properly tune an alky system.

Just an FYI, we can't say anything about any system without some very specific information.

1. CID
2. Compression (true compression, not what the piston mfgr tells you)
3. Fuel pump GPM @ 8000 Crank RPM (flowed, not something guessed from some dude on Ebay)
4. Nozzle Sizes
5. Main jet size
6. High Speed Jet size and pressure (if you run one)
7. Altitude
8. Humidity
9. Temperature
10. Barometric Pressure

All of this plays into a "safe" base tune up and is part of the big picture.

Without one piece of that info, you're not going to be able to get into the ballpark without a LOT of trial and error (and if with a blower, a lot of burned up parts).

Once you have that info, and your baseline, you can then use some simple data logging...buy a EGT with 2 probes, and move it around from pass to pass to find your hottest cylinder. You can then tune via EGT. Once you have the temperature range you want in the EGT, it's just as simple as plugging in the numbers to a weather station, and it'll tell you what jet to run, and if needed what nozzles to change to keep the same system pressure.

Hope this helps...

davis419b 02-13-2008 02:39 PM

GMC.... You are exactly right, the main jet is too small, my mistake, not allowing enough fuel to return back to the tank. I ran an 800hp, 463SBC, with a terminator on it . My main jet of choice was an 85 with 39 nozzels. When I ran my backup 377SBC all I did was use a 33 nozzel and the same main jet. In my opinion the barrel vale should be between 25 & 30 percent. I feel like this guy had the barrel valve lean thinking it would take fuel away from the engine not knowing it would only lean it at an idle.

OneBadGMC 02-13-2008 03:53 PM

I agree with you on the barrel valve, it's too lean.

But saying you ran 33 nozzles and 88 main jet means very little because without pump flow information you don't know what the system pressure is.

Too little system pressure won't atomize the fuel properly, and will as such reduce performance.

Most of the guys I know who are serious about this run extra bypass canisters (known as pump sizers) to get their main pill between 90-110.

This way you have about a 1% differential between jet sizes. Stray too far away from that range, and making a jet change is either too little of a change or too much. The orifice size is a differential from one jet to the next based on area.

Jim Hatley has a nice web based calculator that can be used to calculate system pressure (with or without forced induction). It's setup for nitro, but if you enter 0 for nitro, it assumes alky. It won't work with gas.

http://dragracemath.jimhatleyracing.com/fuelsys.html

johnracer 02-13-2008 06:40 PM

Thanks for the education guys. I thought I'd lost my mind for a little bit there.
I hadn't considered the possibility that the main jet could be rich enough to cause milking too. Mine always seemed to be a barrel valve issue. I had mine set a 17% as well and seemed to be fine. It was a little hard to start cold or hot, and I knew it was probably the barrel valve being too lean, but it was running too good to mess with it.....

talgregory 02-14-2008 03:50 PM

thank for the help talgregory

zipper06 02-19-2008 08:05 PM

Here i am disagreeing with most of the answers, i also run a 4.1 toilet bowl, but with a DSR pump. The milking does not come from the top end it comes from the startup and warmup/driving to the line. I warm the car up with the pump shutoff 1/2 open and try to get the temp up to 185 degrees before i reach the starting line. I donot run a highspeed leanout, but i'm sure if i did i could run better. Bottomline with a ron's injection you will milk the oil no matter what you do.

I run with 18 percent leakdown and depending on the weather and temp. .085 to .100 return jet.

It's just what i run and my experience.

Zip.


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