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Found the root of engine problem


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http://a8.cpimg.com/image/F4/39/13358068-f981-00EE00DF-.jpg

 

Good call Scotty!

 

Can ya believe I cracked a forged piston!?!

 

That is piston #4. There are pits on the piston showing either detonation or metal hitting it. I even have pits on the bowl area on the head.  

 

I did NOT hear any loud audible knocks, I heard a _little_ pinging on  the last 2 runs but NOT something that would warrent this amount of damage to a forged piston.

 

The other 3 pistons are in perfect shape, just #4 is FUBAR'd. The wall has a little scarring on it but is not bad and may  be able to get honed out. At least the forged piston didn't shatter!

 

The TEP Metal shim head gasket is AWESOME!! !! !! !! The gasket is in absoulte PERFECT shape. Anyone owning a Starion that isn't going to a copper gasket NEEDS this head gasket!

 

Lizzord I doubt your stock pistons will be able to take anywhere near this amount of abuse and hold. But good luck!  ;)

 

PS I still love my car...LOL  ;D

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Well not good but it makes sence.  What does the cylinder look like?  I bet the bearings are still good though.

 

I have been thinking, you have mentioned that you get good fuel pressure but are you sure you have the fuel volume?   What kind of pump are you using?  What kind of fuel filter are you using?   I still find it hard to believe that it is just the octane of the fuel, this just keeps pointing to lack of fuel.

 

kev

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I seem to remember there are 2 ways to mess up a piston while detonating , and the edge damaged is fuel and dead(holes usually) center is timing....., correct me if im wrong! (please) , I drove my car home the night i goofed it up , about 5 miles and still a re-hone hooked it back up , balancing is a concern as you will have to have the piston weight, these blocks are real tough that is one of our stongpoints . Id have loved to have a tep metal shim gasket , but my motor block was o- ringed and stev-o from tep said that was a nono for that gasket , Maybe its time we asked Bill TSG if that victor heinz MLS gasket could still happen ?....... this is what the big boys run and offers a added feature of stacking extra shims to get that CR down  abump good for us guys who have had a mill or 3 ;D Hope your back asap Mike K ,Scotty
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holy shizer batman.  lizzord has a rebuild coming soon ;D

LOL well as is i cant get my new springs on so my car aint going any where till i get my new springs and 284 cam in. But i wont run as low oct as them and not as much compression ratio.

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Well not good but it makes sence.  What does the cylinder look like?  I bet the bearings are still good though.

 

I have been thinking, you have mentioned that you get good fuel pressure but are you sure you have the fuel volume?   What kind of pump are you using?  What kind of fuel filter are you using?   I still find it hard to believe that it is just the octane of the fuel, this just keeps pointing to lack of fuel.

 

kev

 

Kevin

 

I run the 125psi CNM fuel pump

K+N fuel filter

Stock fuel lines

750cc injectors

34lbs baseline

1:1 rise with boost.

had total timing at 24 degrees @15psi and 21 degrees @18 psi

 

Had the fuel cranking and MAP values up.

Fuel pressure was around 50psi on one of the 15psi runs

 

My high A/f readings were in the 13's but I could not get them down further.

 

Like I said this all happened when I let off. It pulled right to 6K seconds before that fine. I let off at 6K the BOV swooshed and the puff of oil out the pipe. This is what baffles me.

 

I know what bad detonation sounds like but I never heard any abmormal knocking. Very light ping  on and off, but your bound to get a little of that when you tune your setup.

 

Light cylinder scoring on that cylinder. 1,2 and 3 look new.

 

Darryl care to chime in on your race fuel needs?  :)

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Mike are you running an EGT gauge?  I used the cnm pump on my 20G but when I went to the EIP intake with 4 72lb/hr inj I started to lean out really bad at anything over 10psi and above 4k rpm.  I really didn't notice a ping but the a/f went way lean and EGT shot way up and of course power dropped off.  It's not a pressure problem it a volume problem, it might not show up on the fuel pressure gauge.  That little pump wasn't enough to keep everything happy.  I put an inline pump in and that solved my problem.  
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That's too bad Mike. Remember to check the cylinder for roundness up top. Mine warped somewhat, and needed bored again. I had .040 over stock replacement 7:1 pistons when they did what yours did, but didn't crack like that. The wall up top was warped & called for boring again.

For what you are wanting from your next engine, I would do a line hone, and have the straightness of the crank at least checked.

The bearings take a beating from detonation too. It is like taking a hammer and hitting the top of the piston as hard as you can over and over.

At least most of us got in a good summer of driving some eh?

Tim C.

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I wouldn't have believed it if I hadn't just seen it with my own eye, (singular on purpose for those who know, lol) that is amazing.  Mike I'm sorry that happened to you.  personally I'd push that sucker out, attach a honing thingy to my drill, throw it down in that cylinder, hone it, mic it and and if it's anywhere near .044 over stock I'd slap a new piston in there, but I know you guys are more professional than me.  what freaks me out is that it's broken, not melted but broken.  I know detonation plus pre ignition can create welding temps in a motor that would melt steel in a matter of seconds, but what makes stuff crumble like that?  Do we need 7:1 Pistons? I mean is that why Lizzord's motor is holding up?

 

edit:

I'm pretty interested for obvious reasons so I'm doing some research.  Heres a piston that looks a bit like yours Mike http://www.sacskyranch.com/piston.jpgThis is from: Preignition damage to top of piston from continental engine.

Cause: Jet fuel mixed into aviation gasoline lowered fuel octane

 

Swirl markings on top of piston are normal combustion pattern markings. They show how the hemispherical (dome shaped) cylinder head and the induction system swirls the mixture for better mixing and burning.  This is about an airplane engine but I think it's a great explaination for those of us struggling to conceptualize what's happening in a motor when this type of damage occurs.  It's long so skip it if you already understand.  After spark ignition the burning fuel causes a pressure wave that travels outward from the plug tip. The surface of the pressure wave, which we shall call the flame front, expands outward typically 40 to 50 centimeters per second. The flame front is ragged and "fractal" as turbulence and swirls in the mixture disturbs the front. This turbulence increases the surface area of the flame front causing more unburned fuel to be in contact and thus increasing the flame front velocity and hence the speed at which the fuel burns. The faster the fuel burns, the faster the pressure rise in the combustion chamber. Typically a pressure rise of 20-30 psi per degree of crankshaft rotation.

 

During normal combustion there is a boundary or thin layer of fuel/air mixture just above the metal surfaces of the combustion chamber. This boundary layer is in thermal contact with the cool metal whose surface temperature is well below the ignition temperature of the fuel/air mixture and does not burn when the flame front passes over it. This boundary layer is roughly the same temperature as the metal below and acts as an insulating layer preventing direct contact of the metal to the flame.

 

Deposits from unburned or partially burnt fuel collect in the boundary layer especially in isolated pockets

 

causing at times significant build-up of carbon deposits. Typical areas are between the seat and the cylinder wall and at the juncture of the combustion chamber and the cylinder wall.

 

Turbulence, by speeding up the flame front reduces the thickness of the boundary layer and reduces the buildup of combustion deposits. Combustion chamber designs, such as the hemispherical type used in angle head Lycoming and Continental engines, that cause the fuel/air mixture to enter the combustion chamber in a swirling motion add more surface area to the flame front leading to better fuel atomization, thinner boundary layer and more rapid pressure rise and less carbon build-up. Parallel head engines lack swirl and have greater carbon deposits (especially the Lycoming O-235). Thus one can check the relative combustion efficiency of different engines by the amount and distribution of carbon deposits. Engines that leave more carbon or irregular build-ups of carbon leave more unburned fuel in the combustion chamber than do combustion chambers that leave slight but uniform deposits. Pilot technique influences the amount of carbon build-ups as a rich mixture allows more deposits to form.

 

continued:

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Sometimes the pressure increase in the combustion chamber is great enough to cause the fuel to self ignite. This usually occurs in areas of pressure amplification such as at the edges of the piston dome where reflecting pressure waves from the piston or combustion chamber walls can constructively recombine to yield localized high pressures and temperatures. Sometimes detonation results from the fuel pre-igniting from a hot spot in the combustion chamber. One reason why Continental point one spark plug toward the exhaust valve is to propagate the flame front across the hot exhaust valve early before the pressure (and temperature) in the combustion chamber has risen very far so that only unburnt gasses is in the area of the hot exhaust valve surface later in the combustion cycle when temperatures of the fuel become hotter and more likely to be ignited from a hot surface.

 

During detonation the almost instantaneous ignition of the fuel/air mixture causes such a rapid pressure wave that shock waves are produces that pound against the insides of the combustion chamber and piston. These shock waves are what cause the knocking sound in your automobile engine but which unfortunately are not heard in our more noisy aircraft engines. If these shock waves are strong enough to mechanically "ping" the walls of the combustion chamber they are strong enough to sweep away any unburned boundary layer of fuel/air mixture near the metal surfaces of the combustion chamber. Without a boundary layer the metal surfaces of the piston are exposed to the combustion flame. This destruction of the boundary layer that allows the combustion flame to burn through the piston.

 

During detonation portions of the boundary layer are swept away causing a rapid rise in temperature of the surface. This localized heating causes small areas of piston melting or hole burning in the piston. As we mentioned earlier usually this is located on the edge of the piston next to the cylinder wall where pressure waves reflecting off the wall combine and amplify the pressure at specific locations. Sharp bends in the metal such as at the edge of the piston and along valve cut-outs in high compression pistons are difficult for boundary conditions to provide protection and are usually first damaged by detonation.

 

If the detonation is minor or doesn't last long the result is that carbon deposits in the area of boundary layer failure are burnt off the surfaces leaving bare aluminum showing. The deposits can reform if the conditions that cause detonation are quickly terminated such as a power change made by the pilot. In such cases little or no engine damage may occur.

 

In more severe or prolonged detonation, local temperatures melt the aluminum causing "termite holes" in the piston. The absences of carbon deposits, especially in areas prone to boundary failure such as next to the edge of the piston, offer telltale evidence of detonation.

 

Detonation damage is not limited to burning of holes in pistons or the combustion chamber (typically between the valve seats). The rapid increase in pressures can over-load the rod bearings causing lubrication failure and quite possibly bearing failure. There could be other more hidden damage caused by detonation such as detuning of engine counterweights and resultant over stressing of the crankshaft or propeller.

 

The amount and location of carbon deposits depends on may factors including combustion chamber design,

 

fuel distribution, fuel fractional distillation in he intake tubes causing the separation of light and heavy ends to go to different cylinders, power settings, fuel type, oil consumption, to name a few. However, with each engine model a typical build-up occurs that is relatively consistent from one engine to another of the same model. This requires the examiner to observe normal deposit patterns in many engines so that abnormal patterns are identifiable.

 

With any engine type, burning of holes into or through the piston firsts require the destruction of the boundary layer and a burning off interceding carbon deposits. Evidence of boundary layer destruction by detonation is best early identified by the complete removal of carbon deposits in areas normally observed to contain carbon. This removal often is localized and close to the outside edge of the piston dome.

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dang Chip you did manage to stay awake thru most  of them clases, :) j/k

now don't  get all upset if you see the outter  area of your piston all wet looking and clean this  can be cause'd by excessive oil getting by the oil rings also what Chip is talking about is a  dry clean  no oil at all,

 

and as for Lizzords engine the only thing on earth that'l save that engine  is  him losseing the car keys ;) sooner or later it's going to  go bang  hehe

much later we hope Lizz  ;D

not sure if it's help'd hold it togather but one of the first things he did was go to a 3/8 fuel line and a larger pump

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This is some GREAT info guys!

 

I am absorbing all of it.

 

Fuel pump is going, stock lines are going and I am putting a small statue of the Lord on my valvecover so he can protect the new motor. :)

 

If you look at Chips post it states the cause of that cracked piston was an octane issue. I still feel the pump gas was a big part of it.

 

Actually the 9psi run was the best graphical run I made.

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Maybe you are right Mike.   All of this still points to a fuel issue over a timing issue.  Chip's post really emphasizes the octane of the fuel and what can happen if it is lowered.  I still think that the pump you are using doesn't have the volume needed though.

 

What are you looking into now for pumps?  Walbro?  MSD 2225?  Maybe even the Bosch 500hp pump by TEP?

 

Damn good explanation Chip, btw!  It went well over my head and I am an engineer!  Are you an Aerospace or combustion engineer?

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Well thanks gents but I could only wish to stroll around with that kind of knowledge in my head.  I understand it when I read it but most of that post is copied straight from another site.  Same thing I did with the Torque VS HP post so many people liked.  I tried to give credit at the beginning when I said "This is about an airplane engine but I think it's a great explaination for those of us struggling to conceptualize what's happening in a motor when this type of damage occurs.  It's long so skip it if you already understand."  But I should have been more clear that it was cut and pasted.  I don't want the credit for it I only want to help us all understand it so we can avoid future damage like Mike is going through.  I hate hackneyed statements but if we don't learn from our mistakes and the mistakes of others they we are doomed to repeat them.  I'd include the link but I used the entire article so if you want to read it it's right there.  Next time I'll just site my references correctly like a good little english major should.

 

LMAO Kev I'm a BullS... enginineer.  I wanted to be an engineer because that's what all my peers are.  My degree is in English because Applied Physics was cutting in to my social life too much when I was in college.  hehe

 

One thing I have discovered personally is that whenever you're interested in DETAILED studies of the dynamics of internal combustion engines you can count on airplane engine makers to go all out.  And for good reason, I mean no other type of engine will be so highly taxed yet expected to be very reliable.  Boat engines are about the only other situation where the load is so constant, but if they fail you stop and get out the paddles.  We know what happens when airplane engines fail

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and as for Lizzords engine the only thing on earth that'l save that engine  is  him losseing the car keys ;) sooner or later it's going to  go bang  hehe

much later we hope Lizz  ;D

not sure if it's help'd hold it togather but one of the first things he did was go to a 3/8 fuel line and a larger pump

Well once we get this going good with cam and good boost conrol i will take messures to "save" the motor for longer then it would last with a 2 stage boost control set up. So i am not running very high psi till i have race gas. But their is really no way around it its just a matter of time im hopeing it will be a lot of time :D

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;)Chip i caught the drift that you weren't the  originator of that long wind'd  explanation but you still deserve the credit for  finding and posting  good work  ;D

 

Lizz i  wasn't picking on you   just trying to add a little  humor to a  real serious topic,

besides i  knew you could handle it ;)

 

i know i'm not  as savy as a lot of you guys on the make up of  the fuel they sell us these days , but being from the old school so to speak , i've been wondering if  your problems aren't relate'd to the  fuel they are selling to day,  in the 60's  you had  sunoco 105 or 106 octane and  altho they  try to tell you  todays gas is just as good  with modifie'd  formula's beleave me  there's no comparison to it

one thing   you could tell is the ability of it to still  be useable  a couple  yr's  after it  has set in a gas can, another  thing if you left it in an open container for  very long the container was empty , not so with this stuff today it may loose a little volume but  it may as well be water  for  it sure won't burn but will stink to high heaven

another thing i learn'd  is that most people think of  gas in reverse, they  think high test burns faster then reg , well that backwards,  reg burns  much faster and  has a tendency to explode much more  so then high test, the  higher the octane the  slower more control'd the  compustion chamber  ignition is , causeing a nice smooth  power  makeing   expantion, with reg  gas and  high compustion chamber pressures  this fast  burning  can cause flash fireing inside of the  head chamber , or more then one fireing  lines burning at one time , the multipul  fireing or burning  area's  cause an explosion when they  meet, , this is where you get the   damage , it's  super high pressure wave and  very high temps , that may be   in isolate'd  spots in the head or piston area,

i can remember seeing a demostarion of this  useing a long plastic  tube and  a few drops of  reg and  some of high test, first he use'd the high test gas , cap'd the  ends and use'd a ball to  roll from end to end to mix the  vapors,  then ignit'd one end of the tube, the resulting flame wall  with the high test  start'd at the ignition point and travel'd smoothly down the  tube and end'd with a nice poopth sound at the end,  now  when he did the same test  with  reg , the  flame wall start'd  to move along the  tube but at mid way   the flame flash'd to the other end and start'd to burn from both ends , and when they came togather   it sound'd like a   cannon going off , this was the  best visual  aid i'd  to this day ever seen to explain the  spark knock or pinging we  get with  a gas engine, sorry  for being so long wind'd but i'm wondering if it's the fuel  we're useing causeing this damage to  the engines , because no matter how much they claim diff there is no way to compair the old lead'd high test fuel to this  junk they sell today, just my  2 cents

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After having a conversation with Glen he had said Mike K's dyno at 15psi looked similar to his dyno on his To4. That turbo was to small (not on the compressor side), but on the exhaust side. Apprently, somehow(don't know how scientifically it was done), he discovered that a larger exhaust housing would indeed help in power output. According to him, his findings, and the other guys in Aussie that he's worked with, the head flows alot on the exhaust side, and requires a decently sized Exhaust A/r.. something an 8cm2 20G still doesn't have enough of. The compressor was efficient enough, but there was tons of backpressure sitting in the exhaust.

 

The more boost you run on a choked up exhaust, the more likely you are to spray fuel on a very hot spent charge. Likewise, all the new (hopefully cool air from the Fuso) will be severly heated. EGT's would likely show this.

 

Now I do not know first hand if this is actually the case on turbo exhaust sizing.. but hopefully I will get a chance to find out before I upgrade turbochargers from the 16g I will be running.

 

I still believe there is something else there, as the A/F ratio was way to lean for 18psi. 13:1's are garunteed knock and possible blow. It only took 13.2:1 AFRs for my buddies 13B rotary to kill itself (ate apex seals alive) w/ 3mm apex seals on 17psi, and thats at 5500Ft above sea level (so air volume equivelent of maybe 14-15psi at sea level). Granted higher octane will solve it, but I strongly believe that you can get some power out of pump gas... 8:1 is still not very high.

 

Likewise, I don't believe that its nessisary to run 18psi, I think we need to find what it is that causes that loss from 4k and up (perhaps thats the exhaust housing on the turbo causing this) that would net us plenty of street usable power (300-350 is more than enough for a street 4 cylinder, even 280-300 is gonna kill most any car that bothers you on the street). 15psi should do that for us... IF we get rid of the dip down at 4k and up.

 

Joel

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The more boost you run on a choked up exhaust, the more likely you are to spray fuel on a very hot spent charge. Likewise, all the new (hopefully cool air from the Fuso) will be severly heated. EGT's would likely show this.

 

Now I do not know first hand if this is actually the case on turbo exhaust sizing.. but hopefully I will get a chance to find out before I upgrade turbochargers from the 16g I will be running.

 

Maybe something as simple as a custom header would help out?   I know that Bill TSG has higher rpm power with a slightly smaller turbo, MPI, and SFP header.

 

kev

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That sounds reasonable joel but if it's the case then why does my 20g with the stock (all be it ported) TDO5 exhaust housing pull hard straight past 6 grand with my current set up?

 

Another question I've been meaning to ask is what would cause and engine to pull hard all the way to/beyond redline in 1st 2nd and 3rd gear but lean out in 4th and 5th?  I mean I was  under the impression that fuel demands should be the same no matter what the speed of the car is.  RPM is RPM right.  I can barely run 10psi up above 90mph but 20psi was pulling very very hard in the first 3 gears with no knock and no octane booster.  The way I see it faster speeds should get you working in the lower load points on your fuel map.  the car's already moving fast so the load on the engine should be less than if it's stopped or rolling at 20 or 50 mph.  I know exactly what Mike is talking about when he mentions chugging under boost in an over rich condition because that was happening to me at high speeds and low boost settings.  This is making me think that I was in a poorly tuned load point on my fuel map and that my a/f guage was just inaccurate when it read lean.  It's really hard/dangerous to tune on the highway alone.  That's why I was on my way to the dyno but we all know what happened there.  Guess I should be glad that head gasket blew, otherwise i'd have had no reason to pull the vavle cover and find the jacked up cam.

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That sounds reasonable joel but if it's the case then why does my 20g with the stock (all be it ported) TDO5 exhaust housing pull hard straight past 6 grand with my current set up?

 

Thats the reason I posted it... I wanted to see what others feel/think/see. If I have issues getting mine to pull to redline hard on my 16G, I may be asking you some questions on your setup etc.

 

Another question I've been meaning to ask is what would cause and engine to pull hard all the way to/beyond redline in 1st 2nd and 3rd gear but lean out in 4th and 5th?  I mean I was  under the impression that fuel demands should be the same no matter what the speed of the car is.  RPM is RPM right.  I can barely run 10psi up above 90mph but 20psi was pulling very very hard in the first 3 gears with no knock and no octane booster.  The way I see it faster speeds should get you working in the lower load points on your fuel map.  the car's already moving fast so the load on the engine should be less than if it's stopped or rolling at 20 or 50 mph.  I know exactly what Mike is talking about when he mentions chugging under boost in an over rich condition because that was happening to me at high speeds and low boost settings.  This is making me think that I was in a poorly tuned load point on my fuel map and that my a/f guage was just inaccurate when it read lean.  It's really hard/dangerous to tune on the highway alone.  That's why I was on my way to the dyno but we all know what happened there.  Guess I should be glad that head gasket blew, otherwise i'd have had no reason to pull the vavle cover and find the jacked up cam.

 

Load goes up in each gear. Stopped your gear ratio multiplies the torque out, and load is minimal to power requirements to move X weight with X drag at X speed. As you go up in gears, load increases (higher gear, less torque multiplication, more drag).

 

Another example of this is the reason why you test a car in a high gear going up a hill after playing with the fuel or ignition systems. You are more prone to detonate due to the high load. When you tune your car, you should do so as much as you can in 4th gear. Thats the close 1:1 ratio of the gears, and a good gear to get your car loaded up. Fuel requirements will go up due to the increase in resistance. Best thing to do is tune you maps on flat land in 4th gear (empty road). You need to tune for your lowest load point and your highest load point, and gradiant the rest in between. No jumps or hopping around. On the haltech thats pretty easy, because each RPM map there are graphical bars... when all is said and done it should look like a slope (small bar to high bar).

 

I would tune the car overly rich at first, choose one load point and one high point. Tune those 2 load bars. Then smooth out inbetween. Copy all those load bars to every last RPM map. Add 5-10%  fuel as RPMs increase for safety. Tune each rpm independantly. Now tune up the ignition map to farther optimize. Fine tune each RPM map after your done with the ignition map.

 

Joel

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BTW: The studdering can be a rich or lean condition.

 

If it studders and seems to go no where, its likely lean.

 

If it studders and wants to slow down, its likely rich (bogging down).

 

Joel

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It may be the compressor housing, but I don't boost spike so I thought it was flowing OK. Bill_TSG runs a 20G and pulled 320HP and 340 ft/lbs. His pulls don't drop like mine at 4K but he does run a SFP header..hmmm

 

The fuel we use here is the ethanol blend.

 

I just dropped my shortblock off at the machine shop.

 

I need a new block and 2 new pistons along with some new rings. While it's out new bearings and lighten and knife edge the crank. Also going to remove the excess webbing in the sump area.

 

My machinist (this guy is THE best IMO) he looked at the piston and said it looks   like timing because of the location of the crack. BUT he said after I expalined the situation that it looks to be more of a preignition condition and he thinks that is ultimately what caused it. He said lack of fuel would cause a hole in the center of the piston. Timing is to the edge.

 

I told him I ran pump gas and he said I should be running 100-110 octane or don't even bother turning up the boost.

 

As far as the 4K drop off... I was overlaying grids and found this.  It is too similiar with all the modifications I have done. Hmm

 

http://a1.cpimg.com/image/C9/27/13381321-a21a-020000F9-.jpg

Magna   15psi 340 ft/lbs  259 HP

TBI 18psi              283 ft/lbs 217HP

 

Your looking at 2 dyno pulls. The lower numbers are on the TBI @18 psi and additional injectors  . The upper numbers are with the Magna. You can see the performance increase the Magna provided. But the same 4K decline is there.

 

I was running around 11.5 A/F in the run with the TBI @18psi.

 

Even on the rich side on the TBI the 4K drop off showed. This is why I feel I was sending enough fuel, but not high enough octane.

 

I run a 3" convertor which I will try removing. Other than that I can try a header. Short of going to a new turbo there isn't a whole heck of a lot else I can really do.

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Here's another good article Mike, everyone.  Speaks to finding the cause and fixing it.  Has a few minor contradictions from the other article but personally I like to read everything and form my own general understanding.

http://www.zhome.com/ZCMnL/PICS/detonation/detonation.html

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All this talk about the header, why not just port and polish the stock exhaust manifold, I can't foresee the header getting that much more flow over the stock Manifold unless it's runners are alot larger.

 

Sounds like maybe something done with the wastegate would be in order, external WG? Along with a good PnP on the exhaust manifold and exhaust ports on the head.

 

It just seems to me that the price of the SFP header is a bit steep without knowing it's runner sizes. That could be money spent on something that really doesn't flow any better, the back pressure is all being created at the Compressor's exhaust wheel and the waste gate itself. I can see the SFP header flowing *slightly* better than the stock manifold, but then again, how well does un-dammed water flow into a dam?

 

 

 

Don't mind me, just thinking outloud here  ;)

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