Oil %

[dwilfong]

I am looking for some input on mixing fuel for my 91RS.

I was looking at getting 5 gal. of 50/50 nitro methanol mix from VP and mixing my own fuel. the price is right right around $100 a can at the local speed shop.

Running thew the numbers came up with %10 oil will make %45 nitro mix.

Has any one tried this mix ratio in there big eng? and if so how did the eng hold up?

Right now have run %40 and %55 with %16 oil and had no problems. Will going down to %10 oil work.

Also what oil works the best. Castor or no Castor to the mix?

David

 

[Blackout]

Others will chime in, but from what I have heard, the larger engines like more oil. As much as 20% with a little castor.

 

[John Knight]

Run 18% or more for a 90, 91 or 101 if you want it to last for years. Just ask Andy about the gold head 90 he got from me.

 

[ALLAN YUEN]

50 Nitro + 40 methanol + 10 Klotz 100% SYN + add 2 cup Castor into mix 5 gallons = 50% Nitro with 19% OIL great last long run

If you use 50/50 Nitro& Methanol + 10 Caster Will be short life run and will replace new piston/sleeve because will get overheat Good luck!

 

[Tom Foley]

. Will going down to %10 oil work.

David

Not for long !!! h34r: h34r: h34r: h34r: h34r:

 

[Joe Warren]

I am looking for some input on mixing fuel for my 91RS.

I was looking at getting 5 gal. of 50/50 nitro methanol mix from VP and mixing my own fuel. the price is right right around $100 a can at the local speed shop.

Running thew the numbers came up with %10 oil will make %45 nitro mix.

Has any one tried this mix ratio in there big eng? and if so how did the eng hold up?

Right now have run %40 and %55 with %16 oil and had no problems. Will going down to %10 oil work.

Also what oil works the best. Castor or no Castor to the mix?

David

Big motors run best on More Oil. I normally run 20 percent But I have been up to 22 percent..... There is No better Quality Oil than KLOTZ. the guys that tell you they are running 10-12 percent in the Big Blocks are buying sleeves Often.... Head Volume,Cooling water, Squish clearence & Pipe length are critical on big engines too..... They need to make a little heat....

 

[Al Hobbs]

I like 15% synthetic and 5% castor in the fuel for big engines.

Al Hobbs

 

[Buckshot]

I am looking for some input on mixing fuel for my 91RS.

I was looking at getting 5 gal. of 50/50 nitro methanol mix from VP and mixing my own fuel. the price is right right around $100 a can at the local speed shop.

Running thew the numbers came up with %10 oil will make %45 nitro mix.

Has any one tried this mix ratio in there big eng? and if so how did the eng hold up?

Right now have run %40 and %55 with %16 oil and had no problems. Will going down to %10 oil work.

Also what oil works the best. Castor or no Castor to the mix?

David

Big motors run best on More Oil. I normally run 20 percent But I have been up to 22 percent..... There is No better Quality Oil than KLOTZ. the guys that tell you they are running 10-12 percent in the Big Blocks are buying sleeves Often.... Head Volume,Cooling water, Squish clearence & Pipe length are critical on big engines too..... They need to make a little heat....

David,

As you can see there are many ways to skin a cat. Low % oil has worked for me, but obviously not for others. Sure more oil is safer but it does not burn very well either.

I've got a 7 year old CMB EVO 1.0 that has never been run on anything more than 12-15% oil and it has never had a P/L change. Same motor that out ran a lot of the Twins in ATL & SC a few years ago. I guess I'm doing something wrong?

B

 

[Joe Warren]

I am looking for some input on mixing fuel for my 91RS.

I was looking at getting 5 gal. of 50/50 nitro methanol mix from VP and mixing my own fuel. the price is right right around $100 a can at the local speed shop.

Running thew the numbers came up with %10 oil will make %45 nitro mix.

Has any one tried this mix ratio in there big eng? and if so how did the eng hold up?

Right now have run %40 and %55 with %16 oil and had no problems. Will going down to %10 oil work.

Also what oil works the best. Castor or no Castor to the mix?

David

Big motors run best on More Oil. I normally run 20 percent But I have been up to 22 percent..... There is No better Quality Oil than KLOTZ. the guys that tell you they are running 10-12 percent in the Big Blocks are buying sleeves Often.... Head Volume,Cooling water, Squish clearence & Pipe length are critical on big engines too..... They need to make a little heat....

David,

As you can see there are many ways to skin a cat. Low % oil has worked for me, but obviously not for others. Sure more oil is safer but it does not burn very well either.

I've got a 7 year old CMB EVO 1.0 that has never been run on anything more than 12-15% oil and it has never had a P/L change. Same motor that out ran a lot of the Twins in ATL & SC a few years ago. I guess I'm doing something wrong?

B

Buck if 12% is better why Dont you go down to 6%?????????????????????? :blink:

 

[Buckshot]

I am looking for some input on mixing fuel for my 91RS.

I was looking at getting 5 gal. of 50/50 nitro methanol mix from VP and mixing my own fuel. the price is right right around $100 a can at the local speed shop.

Running thew the numbers came up with %10 oil will make %45 nitro mix.

Has any one tried this mix ratio in there big eng? and if so how did the eng hold up?

Right now have run %40 and %55 with %16 oil and had no problems. Will going down to %10 oil work.

Also what oil works the best. Castor or no Castor to the mix?

David

Big motors run best on More Oil. I normally run 20 percent But I have been up to 22 percent..... There is No better Quality Oil than KLOTZ. the guys that tell you they are running 10-12 percent in the Big Blocks are buying sleeves Often.... Head Volume,Cooling water, Squish clearence & Pipe length are critical on big engines too..... They need to make a little heat....

David,

As you can see there are many ways to skin a cat. Low % oil has worked for me, but obviously not for others. Sure more oil is safer but it does not burn very well either.

I've got a 7 year old CMB EVO 1.0 that has never been run on anything more than 12-15% oil and it has never had a P/L change. Same motor that out ran a lot of the Twins in ATL & SC a few years ago. I guess I'm doing something wrong?

B

Buck if 12% is better why Dont you go down to 6%?????????????????????? :blink:

Sorry Joe, I won't hit that bait.

I never said it was better for anyone/everyone, just said it works for me and a few others.



B

 

[Rudi Arnesen]

I have for years used for 13% oil on engines from 7,5cc and down. On the big block engines I use 15% oil.

Never had a engine failure for the last 10 years, and yes I only run synthetic, no Castor.

Same goes either its a hydro or an offshore set-up.

If you have problems with engine failure, don't automatic assume it got to do with the oil content (unless you use a oil of poor quality) its got to do with all the other things that influence on a engine.

I did a test some years ago. I had a old rigger with a OPS 67 engine running 25% nitro and I was using Klotz oil.

I wanted to see how low the oil content I could possible run before the engine failed.

I started out with 15% and worked my way down. I did run the engine for one gallon of fuel dismantling the engine, inspected it and assembled it again. I lowered the content of oil by 2% each time.

I managed to run successfully with as little as 8% oil without any sign of damage to the P/L or the bearings.

Last run I did was with 6% and the bearings failed after half a gallon. Even then there was not sign of P/L was damaged from it.

Of course this was some years ago and we run our engines harder now, but no way we run then so much harder I need to use 20% oil.

This is my personal experience and it worked for me, but that doesn't necessary means it will work for you

 

[dwilfong]

I knew there would be many different answers to this question. So far the response has bin very good. That is why I asked who has run low oil content.

My 91 RS eats the fuel and I run it allot to test new eng setups. By lowering the oil I am hoping to not have to run 50-55% nitro to get the results I am looking for.

Also the VP 50-50 mix is reasonable and easy to get. On a good day of testing I will burn more than a gal of fuel. 5 gallons will last only about 4 weeks.

I have found that when the weather gets cold 60 deg the .100 spray bar I have will put to much fuel in the eng when running 55%. I have to lean the eng to much and end up taking the plug no holes or seizing. The mods i have done to the P/S seam to have worked in this respect.

I am making many spray bars that i can swap out at the lake to test with.

I am hoping to land on 45% and 10% oil for the final tune.

David

 

[Tom Foley]

I knew there would be many different answers to this question. So far the response has bin very good. That is why I asked who has run low oil content.

My 91 RS eats the fuel and I run it allot to test new eng setups. By lowering the oil I am hoping to not have to run 50-55% nitro to get the results I am looking for.

Also the VP 50-50 mix is reasonable and easy to get. On a good day of testing I will burn more than a gal of fuel. 5 gallons will last only about 4 weeks.

I have found that when the weather gets cold 60 deg the .100 spray bar I have will put to much fuel in the eng when running 55%. I have to lean the eng to much and end up taking the plug no holes or seizing. The mods i have done to the P/S seam to have worked in this respect.

I am making many spray bars that i can swap out at the lake to test with.

I am hoping to land on 45% and 10% oil for the final tune.

David

Well hopefully you'll have enough parts left to make the program for the Winternats ? What is the objective here ? You can run 90 mph on 20% oil so whats the point ? Saving money can't possibly be the point . I wish you luck in your quest Boating Brother !!

 

[Steve Anderson]

.

 

[dwilfong]

I knew there would be many different answers to this question. So far the response has bin very good. That is why I asked who has run low oil content.

My 91 RS eats the fuel and I run it allot to test new eng setups. By lowering the oil I am hoping to not have to run 50-55% nitro to get the results I am looking for.

Also the VP 50-50 mix is reasonable and easy to get. On a good day of testing I will burn more than a gal of fuel. 5 gallons will last only about 4 weeks.

I have found that when the weather gets cold 60 deg the .100 spray bar I have will put to much fuel in the eng when running 55%. I have to lean the eng to much and end up taking the plug no holes or seizing. The mods i have done to the P/S seam to have worked in this respect.

I am making many spray bars that i can swap out at the lake to test with.

I am hoping to land on 45% and 10% oil for the final tune.

David

Well hopefully you'll have enough parts left to make the program for the Winternats ? What is the objective here ? You can run 90 mph on 20% oil so whats the point ? Saving money can't possibly be the point . I wish you luck in your quest Boating Brother !!

The point is every time I need fuel I have to get it at the race or drive 3Hr round trip to see Otto. Or go to Graves and spend $50 gal for 50%.

If the eng runs fine and holds up. Yes it will save much money and time better spent on testing.

Even if the P/S wear out a little faster it is still only the price of 4 gal of pricey fuel.

I have already run almost 10 gal thew the eng already just testing.

this is a hobby not a sponsored F1 team.

David

 

[Tom Foley]

I knew there would be many different answers to this question. So far the response has bin very good. That is why I asked who has run low oil content.

My 91 RS eats the fuel and I run it allot to test new eng setups. By lowering the oil I am hoping to not have to run 50-55% nitro to get the results I am looking for.

Also the VP 50-50 mix is reasonable and easy to get. On a good day of testing I will burn more than a gal of fuel. 5 gallons will last only about 4 weeks.

I have found that when the weather gets cold 60 deg the .100 spray bar I have will put to much fuel in the eng when running 55%. I have to lean the eng to much and end up taking the plug no holes or seizing. The mods i have done to the P/S seam to have worked in this respect.

I am making many spray bars that i can swap out at the lake to test with.

I am hoping to land on 45% and 10% oil for the final tune.

David

Well hopefully you'll have enough parts left to make the program for the Winternats ? What is the objective here ? You can run 90 mph on 20% oil so whats the point ? Saving money can't possibly be the point . I wish you luck in your quest Boating Brother !!

The point is every time I need fuel I have to get it at the race or drive 3Hr round trip to see Otto. Or go to Graves and spend $50 gal for 50%.

If the eng runs fine and holds up. Yes it will save much money and time better spent on testing.

Even if the P/S wear out a little faster it is still only the price of 4 gal of pricey fuel.

I have already run almost 10 gal thew the eng already just testing.

this is a hobby not a sponsored F1 team.

David

Oh , I know just saying ..mixing your own is a great thing . I just dont see the whole low oil thing . Hopefully it will work out well for you as it does for others . The TH fuel is 30.00 for 60 % - 18 % oil , it did come down a bit .

I did talk to an old friend earlier , Cal Lange , who used to run 7 % oil in Picco 80's with OPS needle bearing rod setups installed . Needles need less oil than bushings thats for sure .

 

[SayMikey]

Everyone has valid points, but the issue will come down to mixture setting when running less oil. Less oil on a lean mixture will cost you big time. Id say if you have a itchy needle finger or tune by ear you will be buying parts and or engines.....

 

[dwilfong]

I have found that when the weather gets cold 60 deg the .100 spray bar I have will put to much fuel in the eng when running 55%. I have to lean the eng to much and end up taking the plug no holes or seizing.

David

What does reducing fuel flow at the spray bar do differently than reducing it at the needle?

The needle is the first thing high pressure fuel sees. the needle works in conjunction with the spray bar to meter the fuel. to small spray bar and the system backs up to big and it is hard to get a good adjustment. If it is too big you will go from to rich to lean with nothing in between.

It is easer to burn nitro in warm air to cold and it is hard to burn. That is why you need to keep some heat in the eng. water temp means allot also.

 

[dwilfong]

I knew there would be many different answers to this question. So far the response has bin very good. That is why I asked who has run low oil content.

My 91 RS eats the fuel and I run it allot to test new eng setups. By lowering the oil I am hoping to not have to run 50-55% nitro to get the results I am looking for.

Also the VP 50-50 mix is reasonable and easy to get. On a good day of testing I will burn more than a gal of fuel. 5 gallons will last only about 4 weeks.

I have found that when the weather gets cold 60 deg the .100 spray bar I have will put to much fuel in the eng when running 55%. I have to lean the eng to much and end up taking the plug no holes or seizing. The mods i have done to the P/S seam to have worked in this respect.

I am making many spray bars that i can swap out at the lake to test with.

I am hoping to land on 45% and 10% oil for the final tune.

David

Well hopefully you'll have enough parts left to make the program for the Winternats ? What is the objective here ? You can run 90 mph on 20% oil so whats the point ? Saving money can't possibly be the point . I wish you luck in your quest Boating Brother !!

The point is every time I need fuel I have to get it at the race or drive 3Hr round trip to see Otto. Or go to Graves and spend $50 gal for 50%.

If the Eng runs fine and holds up. Yes it will save much money and time better spent on testing.

Even if the P/S wear out a little faster it is still only the price of 4 gal of pricey fuel.

I have already run almost 10 gal thew the Eng already just testing.

this is a hobby not a sponsored F team.

David

Oh , I know just saying ..mixing your own is a great thing . I just dint see the whole low oil thing . Hopefully it will work out well for you as it does for others . The TH fuel is 30.00 for 60 % - 18 % oil , it did come down a bit .

I did talk to an old friend earlier , Cal Lange , who used to run 7 % oil in Pic co W's with OPS needle bearing rod setups installed . Needles need less oil than bushings thats for sure .

That is why I asked the question. To see what people have run and have had good luck with.

Dont worry I will race at the Winter Nat's. Saving the testing for after.

Heck if you ain't breaking it you ain't trying hard enough. :lol:

 

[Joe Warren]

David if you buy Johns Techonology Boat fuel with 18% & add 2.5 oz per gallon of the Klotz KL100 Your Big Blocks will be happy! The paper work that came with your RS91-101 engine from the mfger says... Anything less than 20% synthetic/synthetic/castor will shorten the life of the engine & may cause a dent in your wallet!! Now if the mfger built the engine & assembled it. They should know the lubrication needed for there engine? Fact is there is No Advantage to running LOW OIL content! Added Methonal may be easier to burn than Added Oil But it is the Refrigerant in fuel too.... B)