BIG DYNO DAYS #'s

[wmoguy]

What Ken says and what he actually does has been different several times in the past. I'm not trying to throw him under the bus, but my DPS turbo calibration IP was a 3200 pump. Dyno sheets in the sticky at the top of the IDI page.

Heath

Mine goes to 3800..... My dyno run doesnt show it though because the operator didnt know the limiter had been adjusted so he let off around 3300. that said, unless you sled pull i see no smart reason to run it above 3k'ish. i know i find myself talking nicely tl my pickup after pulling a big pass at 3k with trailer in tow.

 

[Goofyexponent]

Why more oil pressure? We've always been taught that yeah we have low oil pressure at hot idle but it doesn't matter because it is a high volume low pressure system and it moves a ton of oil. That having been said, I don't know about anyone else but warmed up going down the road I have 50-60psi going down the road and I have 224,000 miles on this engine. When it's making big power, it has a ton of oil pressure. I guess the PSD has more oil pressure but does that have something to do with the HEUI injection system than that it needs that much pressure to keep it cool. What does a 6bt or a DT360 or Cat 3208 run at with respect to oil pressure.

With THAT much power pushing down on the rods, the crank is going to take a HECK of a beating unless you can up the oil pressure to keep oil between the journals and the bearings.

 

[Goofyexponent]

hey guys the vids of the day are on youtube
http://www.youtube.com/watch?v=mbHG9G7dxUk&list=UUyPZQqun9tTsGtw3DLsq-yA&index=2&feature=plcp

Wow, Russ' truck really turns it on!!

 

[bike-maker]

The crank and the bearings don't actually touch; they have pressurized oil between them. If they do touch, it spins the bearing. The more power is made, the more of a cushion of oil is needed. That's why on a top alcohol or top fuel motor they run upwards of .006" - to .010" of bearing clearance and about 130psi of oil pressure.

 

[Diesel JD]

The crank and the bearings don't actually touch; they have pressurized oil between them. If they do touch, it spins the bearing. The more power is made, the more of a cushion of oil is needed. That's why on a top alcohol or top fuel motor they run upwards of .006" - to .010" of bearing clearance and about 130psi of oil pressure.

Good explanation....but we really aren't making that much more power than stock even if somebody did hit 300-350 RWHP and as I said at anything above idle, with anything other than a really worn crank or set of bearings we make good oil pressure going down the road. AM I wrong in my thinking? Is 50-60 psi really a lot less than what a PSD or Cummins is making oil pressure wise?

 

[rhkcommander]

Good explanation....but we really aren't making that much more power than stock even if somebody did hit 300-350 RWHP and as I said at anything above idle, with anything other than a really worn crank or set of bearings we make good oil pressure going down the road. AM I wrong in my thinking? Is 50-60 psi really a lot less than what a PSD or Cummins is making oil pressure wise?

pressure is about the same as a psd,
http://www.cumminsforum.com/forum/94-98-powertrain/444390-oil-psi-when-warm.html

but older stock psd and cummins aren't 300-350hp either

 

[bike-maker]

Exactly. The huge numbers I listed above are for engines that are producing upwards of 3000hp (top alcohol) and 8000hp (top fuel).
Another thing to remember; looser clearances frees up the drag on the rotating assemble which = free power, but not that much. And it makes the bearings wear out quicker, and increases the chances of spinning a bearing on a cold start up (more important on an engine that you can't easily prime the oiling system on - like an IDI)
All of my engine building experience is with gassers, so the same ideas don't necessarily apply, but one would typically just leave the clearances and oiling system alone on an engine making the hp levels that an IDI is capable of.

 

[typ4]

With THAT much power pushing down on the rods, the crank is going to take a HECK of a beating unless you can up the oil pressure to keep oil between the journals and the bearings.

THANK YOU, someone finally gets it.

 

[typ4]

The crank and the bearings don't actually touch; they have pressurized oil between them. If they do touch, it spins the bearing. The more power is made, the more of a cushion of oil is needed. That's why on a top alcohol or top fuel motor they run upwards of .006" - to .010" of bearing clearance and about 130psi of oil pressure.

Also very well said.


technically, and bikemaker will likely agree, the oil hole position in a rod journal is designed to push the oil in ahead of the max load point so a "wedge" of oil is"created" and protects the bearing/journal as it turns.

 

[typ4]

Someone asked about the difference in the stock and torque and j2 cam. the sheet is in post 37 here

 

[88 Ford]

What can you do to the bearing to increase the pressure to them? Can you machine the journals clearance a lil and put smaller bearings in too? Would that increase pressure?

 

[FordGuy100]

You can shim the oil pump spring something rather. Gary did it on his.

 

[Goofyexponent]

What can you do to the bearing to increase the pressure to them? Can you machine the journals clearance a lil and put smaller bearings in too? Would that increase pressure?

Machining out the bearings is on;y going to inchrease the problem and drop oil pressure.

When you hear people say "my engine is going, I got really low oil pressure) this is because the mains are taking a lot of wear and the clearance is becoming more and more. More clearance means more oil can freely flow through and there is not enough pressure to keep a film of oil bwtween the mains and crank journals.

Eventuallt what will happen is the crank will get roughed up, then it will gram a main bearing and spin it closing off the oiling port.....now that journal will beat and pound on an oil-less bearing causing SEVERE engine damage. You either need a new crank or hav eit machined by building it up and lathe-ing it back down.

Shimming the oil pump, drilling out oil passages to the oil galley to the crank bearings and using a high quality oil are what you want to do here!

 

[lbzbuick]

Is there somewhere we can read about shimming the oil pump?

 

[gsxjay]

x2 on info on shimming the pump