Scotty's Racing Technologies 494 build

Discussion in 'Race 400/430/455' started by stg1dom, Feb 18, 2015.

  1. BQUICK

    BQUICK Well-Known Member

    Looks good, Dom....does it use stock caps?
    Did you need a custom pan?
     
  2. gmcgruther

    gmcgruther Well-Known Member

    Jim W., so you are essentially saying the oil drain back from the top of the engine hasn't been addressed? I read everyone's comment on here and is wondering if the crank has been knife edged and rounded where it needs to be? This does a hell of a job on windage. Now, the oil pan issue , was there some type of trap built in the pan for oil control for launching? I have studied older nascar engine ( Before the RO engines ) and learned why those engines live long and scream for ever, mainly because of oil control ;) I understand the 470 is a gm cast block, but isn't there away to get better oil control on drain back from the top? Jim, you have the place to find out this and do the same testing as you posted. I think its awesome that you and other companies are working together to figure things like this. Can't thank you or the other guys enough for doing things like this. Thank you again. sincerely Gary M.
     
  3. gmcgruther

    gmcgruther Well-Known Member

    Steve, was there a crank scraper on this pan or engine? Sincerely Gary M.
     
  4. Steve Reynolds

    Steve Reynolds SRE Inc

    I never install a crank scraper, that's usually up to the customer or engine builder. There are very few builds that are identical so that's something I wouldn't attempt while building the pan. Each one should be fit at the time of engine assembly.

    Steve
     
  5. Jim Weise

    Jim Weise 1000+HP

    Gary,

    No concern with drain back on any Buick engines in the car, as a rule. The exception may be those who choose to fill the lifter galley to strength it for use with a solid roller cam, in the iron block.

    What we are discussing here is simply a dyno anomaly.



    JW
     
  6. staged67gspwr

    staged67gspwr "The Black Widow"

    Dom,what happened to your motor before this one if you don't mind me asking?congrats on the new motor btw!!!
     
  7. jake csordas

    jake csordas Well-Known Member

    I believe that dom cracked a cylinder. He put a lot passes on it with the cylinder cracked but decided to freshen it up after it got worse. He had a lot of passes and street time on that engine.
     
  8. stg1dom

    stg1dom Well-Known Member

    Bruce, stock main caps but custom oil pan. I too had the Poston pan and it wouldn't work.

    Jr. is right. I had a couple hair line cracks in #6 and #8. U used that same block with 3 other builds so probably got 18 years of abuse on that same block.
     
  9. BQUICK

    BQUICK Well-Known Member

    Yeah, that's what got my JAGUICK motor, cracked cylinder. It was a shame to teardown a perfectly running, consistant ET motor but better that than scrape it off the track......

    I know it would be costly but has anyone ever sleeved all cylinders? Would cure the cracking and have to make the motor stronger, right?

    Or, maybe it would crack during the sleeving process?
     
  10. Jim Weise

    Jim Weise 1000+HP

    Yup, you can do it.. besides the cost, you need to go to a smaller bore size, to be able to have adequate sleeve/original cylinder thickness.

    I have seen this done for boosted engines, where losing some CI is not that big a deal.

    But it's going the wrong way on a NA engine.. bore size makes HP.

    JW
     
  11. staged67gspwr

    staged67gspwr "The Black Widow"


    wow,well i wish you best of luck and a great season coming up!!
     
  12. buicksstage1

    buicksstage1 Well-Known Member

    Jim, I dis agree that this is a dyno thing. I had 3 of these like this. 2 on the dyno and one in car, I made him put a go pro in the car because I was having a hard time believing there wasn't a windage problem because of his lack of any oil control and sure enough the video showed it falling off but I could not blame him for not wanting to keep his eye's on the track but at a quick glance his swore it was fine. Its near impossible to gauge watch while burning down the track. I am surprised that both you and Scotty didn't try adding oil then removing oil because that would have told the tale if it was sucking the pan dry or getting into the crank.

    I have seen way to many engine failure where every thing is black and blue from the lack of oil which could be caused by tight bearing clearances, tight side clearances, oil pan with lack of capacity, windage problems, a P/U too close to the bottom of the pan is restrictive etc etc.

    You mentioned that the thinner oil help when you tried it and I agree that it returns faster but also the thicker the oil viscosity the harder is it to pull it up the pickup tube into the pump. Using a thinner oil will help because it flows easier and is less likely to cause cavitation inside the oil pump at higher engine rpm. Another problem I see and Mike and I have talked about this before but a real important factor is to small of holes in the P/U screen and or to small of a P/U. Small P/U tubes, restrictive P/U screens can cause pump cavitation. I am sure you have seen the ones I am talking about with the small little drilled holes. I like the larger mesh that Steve uses like in your pictures above.

    My machine shop does a high volume of class race engines, stock, super stock comp etc they spend a lot of time doing there oil control in house not just for HP gains but mostly to make it live. My theory is that nothing leaves with out some sort of oil control ie: stock type gets the factory splash shield and most get a scraper like the ones Mike sells at AM&P that Kenne Bell built many years ago or if its girdled mesh and a scraper.

    This 494 may or may not be windage because it wasn't tested on the dyno, but we do know that oil control is so very important it shold be done before it goes in the car.
     
  13. buicksstage1

    buicksstage1 Well-Known Member

    Here is one of the ones that should oil pressure issues like I post earlier, the steff's kit comes with the bevel bar in it and that is what I used for the scraper. This was tested with a oil pressure drop and retested after the mesh and the problem was 100% gone and held steady all the way through the pull. The only thing I wish I would have done was not make any other changes so I would have been able to see the gains with the scraper and mesh.

    The mesh doesn't have to wrap around the sides either, I cut mine back for fit reasons.
     

    Attached Files:

  14. buicksstage1

    buicksstage1 Well-Known Member

    This is a article I cut and pasted from a quick google, windage issues are a problem for all wet sump engines. This is a good reliable coarse of info.

    Tech Talk #5 Rehers Rules: How to Keep Your Engine Alive
    David Tech Articles By David Reher, Reher-Morrison Racing Engines

    Reliability is more important than horsepower when you have to pay your own engine repair bills.

    You dont have to be a cardiologist like my fellow back-page columnist Dr. Torstveit to appreciate the importance of blood in the human body. Ive watched enough episodes of ER and Chicago Hope to know that even a momentary interruption in the flow of blood to the brain can cause permanent damage.

    At the risk of repeating a clich, Ill state categorically that oil is the lifeblood of an engine. The consequences of erratic oil delivery in a racing engine can be just as traumatic as the medical emergencies on television shows but instead of comas and strokes, the likely results are broken connecting rods and catastrophic engine failures.

    I estimate that nine out of ten connecting rod failures are not the fault of the connecting rod. Almost invariably, a broken rod is the result of a spun bearing -and the bearing failure is usually the result of an oil system problem. If an autopsy of a blown engine reveals even the hint of a blackened crankshaft rod journal, thats strong evidence that a spun bearing was responsible, not the connecting rod.

    When drag racers think about oiling systems, they usually look for ways to increase power by reducing windage and parasitic losses. That approach may be valid if youre contending for the Pro Stock championship, but its risky business for weekend warriors, bracket racers, and Super eliminator competitors. Rehers first rule of racing is that reliability is more important than horsepower when you have to pay your own engine repair bills.

    I should point out the important distinction between wet-sump and dry-sump oil systems. With a wet-sump system, an engines entire oil supply is contained within the oil pan; with a dry-sump system, the oil is stored in an external tank. This simple difference in how the two systems manage their respective oil reservoirs has huge implications for racers.

    A wet-sump system has the advantages of simplicity, low cost, and light weight. Thats why virtually every production engine in the world uses wet-sump lubrication. A dry-sump system is more complicated, more expensive, and heavier than a wet-sump but it offers the important benefit of continuous lubrication under all conditions and the promise of increased power through reduced windage.

    When you consider cost and complexity, a wet-sump oil system is the logical choice for most sportsman racers. The biggest mistake a sportsman racer can make, however, is to try to duplicate the performance characteristics of a dry-sump using a wet-sump system. This simply cant be done without sacrificing reliability.

    Many sportsman racers look to Pro Stock for inspiration. In some instances, the technology that is used in Pro Stock is applicable to other classes but lubrication system design is not one of them.

    Pro Stock engines are universally equipped with dry-sump oiling systems. The luxury of an external oil storage tank allows a Pro Stock engine builder to use an oil pan that is the size of a small refrigerator and to install a vacuum pump that sucks the air out of the crankcase like a tornado. Pro Stock racers use lightweight lubricants and restrict the oil flow to the absolute minimum. I couldnt recommend these tactics in good conscience to any bracket or Super eliminator racer.

    Using a large-volume Pro Stock-style oil pan with a full-length sump is an invitation to disaster with a wet-sump oil system. I insist on using an oil pan with a rear sump on every Super Series bracket racing big-block we build at Reher-Morrison Racing Engine even if the engine will be installed in a dragster with plenty of room between the frame rails for a full-length sump.

    Heres why: When a car accelerates at one g, the oil stands up in the rear of the pan at a 45-degree angle. At two gs acceleration, the oil is plastered to the back of the pan at a 66-degree angle. The same thing happens when the car decelerates, except the oil piles up at the front of the pan, and the oil pump pickup sucks air. With a full-length sump, there is little hope of keeping the oil pump pickup covered.

    The low-viscosity oil that is commonly used in drag racing engines today has the consistency of kerosene when the engine is at operating temperature. You can see for yourself what happens to the oil in a full-length wet-sump pan by filling it with four quarts of water and rocking the pan forward and backward. Tilt the pan at a 66-degree angle to simulate what happens during a two g launch and deceleration. Even baffles and trap doors cant keep the oil pump pickup submerged under hard acceleration and deceleration.

    I strongly advocate using a solid windage tray to shield the oil pump in any wet-sump engine. You may sacrifice a little power with a partial solid tray compared to a full-length screen-type tray, but the oil pressure will be much more consistent if you shelter the oil around the pump pickup. The turbulence inside an engines crankcase is unimaginable when its crankshaft assembly is spinning at 7,000 rpm and its eight pistons are pumping up and down in their cylinders 56,000 times per minute. A full or partial solid windage tray isolates the oil surrounding the oil pump pickup from this whirlwind in the crankcase.

    I have seen the difference in oil pressure that a solid windage tray mounted above the oil pump can make in a wet-sump racing engine. With some full-length screen-type windage trays weve tested on the dyno, the oil pressure fluctuates as the engine accelerates. With a solid windage tray mounted above the oil pump to isolate the sump, the needle on the oil pressure gauge hardly moves.

    For similar reasons, I am not a fan of crankcase vacuum pumps on wet-sump engines. Lowering the pressure inside the crankcase with a vacuum pump can increase power because the crankshaft has less drag just as an airplane can fly faster in the thin air at high altitude than it can in the denser air at low altitude. But from the standpoint of the oil pump, a little positive crankcase pressure is actually desirable because it forces oil into the pickup. Positive crankcase pressure primes the pump and helps to ensure a steady flow of oil into the pickup. When the crankcase pressure is artificially lowered with a vacuum pump, there is less pressure differential to push the oil through the pickup tube.

    One of the best investments a sportsman racer can make for a wet-sump engine is an oil accumulator such as an Accusump. An oil accumulator is a sealed cylinder that contains a floating piston. Pressurized air on one side of the piston forces a reserve supply of oil into the engine if the flow from the internal oil pump is momentarily interrupted. An accumulator works automatically and requires virtually no maintenance except regular cleaning. Unfortunately, accumulators are seldom seen in drag racing. Thats a pity, because they really work.

    You may have an oil system problem and not even know it. Most drivers are too busy during a run to watch the oil pressure gauge. If youve plumbed the pressure gauge with small-diameter tubing that dampens the gauges response, you might not even see dips in the oil pressure. Try connecting the gauge with 1/4-inch I.D. tubing, and mount the gauge where you can see it throughout the run. You might be shocked to learn whats really happening inside your engine!

    The effects of oil pressure fluctuations are cumulative. If the pressure drops to zero when you stop after a burnout, decelerate after a run, or make the turnout at the end of the track, you have abused the bearings. The oil pressure may return to normal when you restart the engine, but youve already inflicted some damage. If you repeat the injury enough times, eventually a bearing is going to fail. And when it does, the damage will be very, very expensive to repair.

    The oiling system is not the place for a sportsman racer to look for power. The potential rewards are small perhaps five or ten horsepower under the best circumstances. On the other hand, the risks are enormous. If a trick-of-the-week oil pan starves the engine for oil, you are going to pay a heavy price. A reliable oil system is the best way to avoid a medical emergency for your motor!
     
  15. nickwhite

    nickwhite Platinum Level Contributor

    Wow, This is a great read I have really learned a lot here.
    My 494 has very good oil volume, but as you say windage should be
    checked. :gp:
     
  16. slimfromnz

    slimfromnz Kiwi Abroad

    Great read thanks Chris.
    I have been contemplating my reply to this thread regarding oil pressure, as many of you know of the issues I had. Now I will probably change out my pickup for an SRE one when we go in for a freshen in April, but I wanted to know what you guys thought of engine oil temp. With our alloy blocks, when the temp gets up, the pressure drops significantly down to 40-50psi. I have only experienced this twice before while spending an 1hr on the freeway. I have since put a temp gauge in the pan and have seen it up over 130'C. I use Brad Penn 20W-50. I run Evans waterless coolant which helps to bring the oil temp down dramatically when I stop. But what is too hot with this oil?
    Cheers
     
  17. buicksstage1

    buicksstage1 Well-Known Member

    You sir made one of the nicest steel oil pans out there! I can't remember what your pick up looks like but I wonder with it being so long if the pick up tube should be bigger? Even in stockish builds there is a pretty big drop in pressure between cold and hot.

    Something else that is different between a stock block and TA is that the TA block is priority main oiling so it does not require any where near the 10-12 psi per 1000 rpm like the factory block needs to live.
     
  18. buicksstage1

    buicksstage1 Well-Known Member

    Something else I noticed is and someone correct me if I am wrong here because it is hard to see in the picture but the oil pressure gauge is hooked up at the front of the engine so there will be 5-10 psi loss from front to back depending on the oil mods done but I also don't see rear oiling which If so am 100% fine with because Every dyno test I have done I run O/P gauges from the front and back side by side and watch them the whole dyno pull looking for a drop and have yet to see one.
     
  19. gmcgruther

    gmcgruther Well-Known Member

    JW, I read that the engine had oil drag ( windage ) that there is a major problem! You can lose a lot of power from oil whipping around. That's why I asked about the crank being knife edged and bullnosed! Here is my other thing I was wondering about, oil pressure ? Why so high pressure ? I prefer high volume over pressure in a not so balanced Buick engine. You would think pressure is ok but think of it this away please, you take a 50 gallon an hr gas pump and set the pressure at 100 psi your not gonna get the volume of a 150 gallon per hr pump at the same psi. Please explain why such high pressure for a engine not twisting 10,000 rpm! The rule of thumb is ten psi per every thousand rpm.. I'm just curious ! What I mean by drain back issues is, why is oil still not deverted away from the crank on the ta blocks? I understand the GM factory block..
     
  20. 8ad-f85

    8ad-f85 Well-Known Member

    I'm not JW :) but...
    That psi/rpm rule isn't really a rule. It's a starting point to a very long learning curve. Every engine is different.
     

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