15w40 or 20w50

BigBadDodge

BigBadDodge

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Question for the oil guru's, currently I use the 20w50 and change my oil after every hook. what would I be loosing if I went to a 15w40 and still changed the oil after every hook. Any advantages and or disadvantges for runing it down the track once?

Thanks,

BBD
 
You may see a gain in HP...thiner oil is easer to pump...but it would be very slite!!!
 
What you will gain in hp, you will loose in in reliability. Use a 20-50 brad penn racing oil. As good or better than any oil on the market and you can get it for like 40$ for 3 gal.
 
Thanks guy's, I understand the reliability and protection from heat and fuel dilution etc.... that I would reciev from the heavier wieght oil. But should it be a concern if I am changing the oil after every hook? We are talking synthetic oil, and hook is approx 15 seconds.

BBD
 
07dodge said:
What you will gain in hp, you will loose in in reliability. Use a 20-50 brad penn racing oil. As good or better than any oil on the market and you can get it for like 40$ for 3 gal.
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Holy chit, I'm not the only one running this oil! No one I talked to ever heard of it before. Worked great in out Prostock tracoors this year and last, and the year before. heck I run it in my DD too!
 
ya the brad penn oil is good stuff, we run it in the pro mod car that i wrench on.
 
Never herad of it.

I am not interested in exstending my change intervalls, I will most likley change after each hook no matter what oil I use as its cheap insurance when considering how much a mod motor costs. I am merly wondering if I could use a lighter wieght oil with out sacrificing the internals at all.

BBD
 
Alot of guys run the 15-40 but some complain of wash out and others don't. Its sorta the luck of the draw.
 
BigBadDodge said:
Thanks guy's, I understand the reliability and protection from heat and fuel dilution etc.... that I would reciev from the heavier wieght oil. But should it be a concern if I am changing the oil after every hook? We are talking synthetic oil, and hook is approx 15 seconds.

BBD
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Absolutely positively do NOT use any type of synthetic oil. Its garbage. I build high performance garden tractor engines, i put synthetic oil in, ya it makes a lil more power but in one run the cam and lifters are junk. Put rotella t (cj4) in and get ten runs out of it and have junk cam and lifters. Put brad penn in and get a 100 and have no junk parts. I also break my engines in with their break in oil, really high zinc content, works wonders. Grantid we run some of the most radical flat tappet cams out there but still. Take my 2cents i have sent alot of money and junked a lot of parts.
 
i used brad penn up at college.....seemed to hold up to alcohol alot better than regular oil......
 
Yes i run schaffer moly 50, 40 runs at 5k+ and the bearings looked like new, change the oil every 5 runs
 
07dodge said:
Absolutely positively do NOT use any type of synthetic oil.
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This goes against everything I have ever been told, I have been using synthetic for the last 6 years. (I hope Gene doesen't see this :)

It's not a dally driver with flat tappets either, it's a mod motor.

Should I be concerened about wash out if I change after every hook?

BBD
 
I have a 55 gallon drum of the older amsoil probably about 40 gallons left. Have been told it is the good stuff, as amsoil has since lowered the zinc content. I run a bypass system, have sent some oil analysis in. After 10 hooks on the oil, the results showed a litte more carbon, than expected. Everything else looked good. This year I ran about 7 hooks per oil change. Of course I am not running a mod motor. Many suggest every 5 hooks to change the oil, cut the filter looking for pieces.
 
I have been compiling a spreadsheet with "initial" oil data...ya know viscosities, ppm Zinc, and other stuff.

IMO I would NOT use a 15w40 in a mod engine. The tolerances are too loose and the HTHS viscosity of 15w40 is just too low to hold up. 15w40 ranges from 4.1 to 4.7 cP regardless of it's being synthetic or otherwise

Also, the zinc content of the old Delo used to be 1480ppm, the new LE stuff is 1300.

So far, the only oil I like on paper is RedLine 20w50. It's HTHS viscosity is 6.1 cP and a Zinc content of 1330 PPM (add a bottle of COMP Cams break in lube and you are good!!!). The only problem is the stuff is spendy....oil changes are over $100 a shot.

oh, has a high flash point too...255C
 
We use Champion All-fleet T 15/40.We change every 3hooks in DESTROKED nad check the filter each time it changed.the mod motors and some of the promod don't run that long to get the oil as hot as the lower class truck because they don't sit and Idle for longer period of time after we get don running I pull the dipstick and look at the oil and feel how hot it got it warm but not hot.I ran the same oil in my minirod 500ci alci,injcted nowater in the block eather the oil didn't get hot eather.
We pulled garden tractor for many years and ran valvoline racing 30w never had lifter failer all our parts came from Chuck Vogle all the parts were builitnever had bearing failers eather.

Dale
 
Hey Scott,

If you like insurance, cheap or otherwise, I would stick with the 20w50 racing oils. If you care enough to change the oil after every hook, then run the 20w50. My .02

Craig
 
The mod trucks, like you run, are essentially needed teh same oil as the tractors now adays. Alot of the gusy are running Cempico (because they have too) Shaffers (because it isn't full synthetic for their race oil) or Penn Grade (again because it isnt full synthetic or a CI4 standard). The tractor guys running flat tappents and roller cams were seiing major wear problems. The Achl boy were getting too much fuel in their oil. The only one I have found is the full race oils, such as Penn Grade or Shaffers that hold up to the abuse these engines take well. 2 of the tractors I work with (Prostock) run teh Penn grade oil. 72 hook in one year and the bearings looked liek new adn went back in. Went half way through teh next year before an injector dropped and burnt a whole lot before the bearing were replaced adn they were still good but was done for better sleeping at night... lol I can't complain about the Penn Grade oil. I ain't a dealer or anything, jstu run in in my trucks and friends tractors adn works extremely well.
 
BigBadDodge said:
Question for the oil guru's, currently I use the 20w50 and change my oil after every hook. what would I be loosing if I went to a 15w40 and still changed the oil after every hook. Any advantages and or disadvantges for runing it down the track once? ...
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You must be considering the difference between street driven engines and your modified engine. Then you must be thinking of what oil does. In any engine the oil is making a cushion between the parts. In regular street-driven engines, the cushion made by the 15W40 is enough to be keeping a layer of oil between the parts. In your modified engine, the torque and forces are being much greater and the possibility of the film being crushed out are much greater. I am not knowing all the answers, but the greater power could be a reason many high performance engines use 20W50 oil. You must do more research. Watson and Scheid could be giving you better answers.

You could send an oil sample to be analyzed after a run when you change it. You might be finding you don't need to change it as much.

Ib
 
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