Washing down cylinder walls, MFI and methanol?

Discussion in 'PSI Superchargers Tech Questions' started by Wheelsup69, Oct 19, 2018.

  1. Wheelsup69

    Wheelsup69 New Member

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    I've been struggling with this year with washing down my cylinder walls and losing the seal with the rings allowing oil into the combustion chamber and blowing so much smoke going down the track that the mosquitoes left the facility.

    Procharger, BBC, Ron's MFI. I suspect that I'm so rich at idle and on some initial passes that the methanol is wiping out the hone on the cylinder walls. Last race I had new rings, new hone and lost it in 5 passes (one was super rich due to an issue with no boost). Couple questions.

    I doubt it would work but If I fire up the car in my driveway and run it leaned out for 15 or 20 minutes (not all at once) will the rings seal against the walls again or do I need to replace the rings and hone again?
    How do you avoid this?
    Do you keep it leaned out until you stage the car and make a pass? I know top fuel runs lean right up until they are staged, then they open up the fuel completely.

    I'm ready to give up MFI and go EFI I've been so frustrated with this. I know my combo is different but the basics are the same. Any help is greatly appreciated.

    Mike
     
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  2. Will Hanna

    Will Hanna We put the 'inside' in Top Alcohol
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    First thing is who is doing the hone and what stone and process are they using?

    Are the pipes wet at idle? To do the type of damage you are describing it would have to be very wet pipes at idle.

    I'm not familiar with a Rons MFI, but if it has a K style barrel valve, check and make sure you don't have the idle return line hooked to the pump saver check valve. Idle check should be a very light spring, the pump saver 200+.

    Was the fuel system flowed and set up for your application? Surely they can get you in the ball park on idle flow.

    There are plenty of blown alcohol engines that run on the rich side at idle. In fact it's pretty common in heads up classes. Now I'm not talking huffing fuel out of cylinders, but wet to damp pipes aren't totally uncommon. It certainly does not cause the damage you are describing.

    There is not going to be anything to fix those cylinder walls besides a proper hone job and proper rings, gap and piston to wall. It might help to let us know what rings and gaps you are running. Too tight of a gap is way worse than too much gap.
     
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  3. Mike Canter

    Mike Canter Top Dragster
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    After a run is the oil diluted and changed cloudy with a color change to light green or brown? What does a fresh set of spark plugs look like after one run?
     
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  4. nitrowannabe

    nitrowannabe Member

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    So this is a blow thru throttle body ?Does Ron use a square barrel valve ? Sheet metal intake ?
     
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  5. jay70cuda

    jay70cuda Well-Known Member

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    My engine builder in Ohio has a ton of expirence with those things. Call him because he will set you straight on how to set that up.
    Level performance , Fremont Ohio 419 3349470
    Dennis is his name. Great guy. Tell him jay said to give you a call.
     
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  6. Wheelsup69

    Wheelsup69 New Member

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    My machinist is doing the honing based on what Total Seal told us to do. I believe it was 220 grit with a couple light swipes of 400. My exhaust is a traditional header into a collector. They are wet for sure, soaked with oil most of this year....
    I ran the MFI set up last year on a different long block and it worked great. We had the tunes dialed in and was running low 4's in the 1/8th. System was flowed for my set up and I work with them prior to every race on tune ups. We started the year going richer thinking this new motor needed more fuel. My guess is it was just too much.

    Rings are gapped for 50 psi boost. 34-36 on the gap.
     
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  7. Wheelsup69

    Wheelsup69 New Member

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    Yes, I run green oil and it's diluted. I've got reading plugs down pretty well. Right now they always have oil on them so hard to get a good assessment.
     
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  8. Wheelsup69

    Wheelsup69 New Member

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    Yes, blow through 2100 cfm throttle body. Square barrel valve. Not sheet metal, Edelbrock Big Chief cast intake.
     
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  9. Wheelsup69

    Wheelsup69 New Member

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    Sweet, thanks. I will give him a call next week.
     
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  10. rb0804

    rb0804 Active Member

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    Out of curiosity, what type and brand of rings did your old long block have? You mentioned total deal, they happen to be gapless?
     
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  11. Wheelsup69

    Wheelsup69 New Member

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    My total seals are not gapless. I was running total seal in my old motor as well.
     
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  12. TOL

    TOL Active Member

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    What exactly changed between your old and new motor?
     
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  13. Bjs344

    Bjs344 Member

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    I'm pretty rough on my stuff but have never ended up with oily plugs. What kind of 2nd ring are you running? What tension oil ring?

    How much heat can you build if you idle on a gallon of fuel?

    Idle egt temps?

    WOT egts?

    Timing?

    Water block with/without water or solid block?

    Are you sure you aren't leaking boost into the crankcase?
     
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  14. Wheelsup69

    Wheelsup69 New Member

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    Both motors are 540" BBC. Old motor was a solid Brodix block, Dart 380 conv. heads, 10.5 to 1 comp, Diamond pistons, Total Seal rings. New motor is New Century Solid alum block, Dart Big Chief 18 degree heads, 12 to 1 comp, Diamond pistons, Total Seal rings, different cam, lifters, push rods, pretty much everything.
     
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  15. Wheelsup69

    Wheelsup69 New Member

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    Looking at a data log, about 450 degrees at idle, 950 - 1000 through the traps. 26 degrees of base engine timing. Solid block, Water heads, no water. My boost has been way down this year but I've attributed it to the Big Chief heads instead of the conv. heads. I'm running a gear drive and the gears I have in it would make 47 lbs of boost on my old motor and only making 34 on the new motor. I've assumed the rings losing their seal has allowed the boost to go past the rings, pressurize the crankcase and is pushing oil into the combustion chamber at holes that aren't under pressure. When I take the intake off there are pools of oil sitting in the intake runners of cylinders with the valves closed.
     
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  16. Bjs344

    Bjs344 Member

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    If I idled my BBC at 450 it wouldn't have any rings left either. It seems to me chevys (conventional at least) like to idle hotter than Hemis. Most on here will tell you 450 is ok but they run Hemis. I go 600-850 with maybe one straggler at 550 and will creep up over 900 on a couple during a good warmup.

    I had one set of heads that I'm convinced was putting boost in the lifter valley. The angles were off just a tiny bit so I used thicker gaskets and it would blow oil EVERYWHERE and fill the puke tank every pass. I would pull it apart and it would show evidence of leakage at the bottom of the intake gasket but it wouldn't ever blow them out. I finally just quit using those heads.
     
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  17. Wheelsup69

    Wheelsup69 New Member

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    That data log was at the beginning of a run. I just found one that was a warm up log and the egt's are 550 - 600.
     
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  18. Wheelsup69

    Wheelsup69 New Member

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    I suspected early in the season that the boost was going into the lifter valley so I started sealing my intake gaskets with right stuff on both sides to make sure that wasn't happening.
     
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  19. Bjs344

    Bjs344 Member

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    I would lean the idle a little and keep looking. What about burnout and stage? Somebody was on here awhile ago talking about hurting pistons in the burnout from being too rich at part throttle. if you're 450 on the chip and you can handle more power at the hit I would consider a converter helper (electric leanout).
     
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  20. rb0804

    rb0804 Active Member

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    Can you explain to me how excessive blow by is going to cause oil puddling on the back side of the intake valves? That sounds more like you have a cylinder head sealing issue between the intake and heads.... it’s already been mentioned once in this thread.
     
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