Disaster

[cobra132]

So much for the big bore stroker. The valve lash adjuster was a red herring. I fixed it and there was still a lot of noise. Also I noted oil dripping from a crack in my right header collector. This engine had 2 days on the dyno breaking in and tuning. A seemingly good tune. Plenty of power. Plenty of oil pressure. Run on 100 octane fuel. Ten minutes on the track at MSRH during which it had a lot of smoke on coming off throttle. Upon start-up for qual it had a loud tapping from the right side on the engine. Saturday I pulled and tore down the engine. There was a ton of oil in all exhaust ports and header tubes. There was tremendous damage to the piston skirts as shown. The ring gaps were wide with the first ring at .025 - .028, second at .026 - .029 and all oil rings greater than .030. Having trouble adding images, will try again. FMR

[cobra132]

I can't seem to add jpegs. Too bad I was hoping for some input. More to follow. FMR

[jeffburch]

FR,
send to jeffburch3@tx.rr.com
I'll add them.
Sorry for the misfortune.
jb

[Al Fernandez]

Man that is a real bummer Frank. I was hoping you were going to get lucky on this one. :(

[AI#97]

I can't seem to add jpegs. Too bad I was hoping for some input. More to follow. FMR

Can the skirts be cleaned up with a bore? Do you know which brand pistons they used? The gap seems a little large on the rings probably why you had the smoke. SHM built that one?

If you still have the old shortblock, I would put it back in the car, use the smaller cams and find a new tuner. Your car should have been making plenty of power with your previous combo. DownUnder's motor is making similar power with stock cams.

If you need suggestions, help or contact help with a new tuner, let me know. I have two VERY good Mod motor guys up here in Dallas....oh, and me! I am working on a rotating assembly to drop into my big bore shortblock at some point this year. Just got to save the funds.

[AllZWay]

That really bites... I was also hoping it was an easy fix and nothing really torn up.

[cobra132]

I'll send the pics to JB tonight. There aint no cleaning these up. I don't want to play the blame game at this point. I just want to get back on track. Hopefully I'll get the car ready in some form for MSRC. FMR

[cjlmlml]

You need pushrods.

[AI#97]

You need pushrods.

No he doesn't, but I am surprised you didn't say he needed a carb! LOL!!!

[Rob Liebbe]

You need pushrods.

You need to get to the track.

[David Love AI27]

Sorry to hear of your troubles Frank, hope you can make it to Cresson...

[jeffburch]

FMR pics.
jb


http://www.argentlab.com/nasatx/jeff/fmr%20piston3_4.jpg

http://www.argentlab.com/nasatx/jeff/fmr3%20nonconcentric%20pistion.jpg

http://www.argentlab.com/nasatx/jeff/fmr4_3%20combustion%20chamber.jpg

http://www.argentlab.com/nasatx/jeff/fmr5%20intake%20side.jpg

http://www.argentlab.com/nasatx/jeff/fmr5%20side.jpg

http://www.argentlab.com/nasatx/jeff/fmr_1_2.jpg

[AI#97]

massive blowby with 13:1 compression looks like you were burning a LOT of stuff with too much heat. If you had to choke it to kill power, that probably didn't help. Could have been running VERY rich and was washing down the cylinder walls. those bores "appear" to be able to be cleaned up. Figure a .020 overbore might work, but you are back to new pistons/rings at the min.

Flat tops in 324 cube motor is pretty high compression.

I will post later this evening...just realized I am late for work!

[cobra132]

I measured the piston to cylinder clearance according to manleys instructions at 0.010 - 0.014. Should be 0.003 - 0.0035 and certianly no more than than 0.005, or am I wrong?. FMR

[donovan]

That just sucks Frank... Keep us posted!

DD

[AI#97]

I measured the piston to cylinder clearance according to manleys instructions at 0.010 - 0.014. Should be 0.003 - 0.0035 and certianly no more than than 0.005, or am I wrong?. FMR

I read this same line in SHM's engine building book...if the pistons were truly that far undersized, they either wore away a lot of material or were letting the oil by and that was causing the smoke. Are you measuring the piston diameter above the top oil ring or below the rings. Only thing that sticks in my mind is how far the pistons will get exposed at bottom dead center from the skirt bore. If they installed standard stroke skirts, the pistons will cock to the side a little at BDC and could start chewing up the piston. Now that I think about it, I need to verify my sleeves can accept a stroker setup! Maybe the motor was setup with hypereucraptic piston tolerances instead of for forged pistons which grow more?

Taking a harder look at the pictures, I see a LOT of detonation burning the top of the piston...ie, pitting. I also see a LOT of burned oil as if you were getting blow by or sucking it in through the intake/PCV. I have had motors that I put 3k miles on and still looked like fresh clean pistons. Something is not right in the a/f mix and getting a lot of oil into the cylinder.

As for the sides of the pistons..., they look like they got hot and expanded too much in the bore. Given the compression of 12.7+ (guessing), you needed 100 octane or even 104 depending on the timing curve. If I run less than 98..I have problems. I never saw the inside of my motor in November 2006, but it died with just one session of 93 octane and the pistons were toasted but the block was fine.

Any idea what the water temps where during the practice session? I don't have any experience with the Darton Wet Sleeve setup. Mine is a dry sleeve so my water jackets are all still aluminum with no water hitting the sleeve. The reason VT originally sold me on this was even heat disapation around the sleeve and more block strength to cope with solid engine mounts.

There are 3 or 4 theories on what happened, but I know you are going to hate my next suggestion. Send the pictures to the engine builder and tell him the scenario and ask questions of "what could have caused this?" SHM has built enough motors that they should be able to say "Yep, that was XXXXXX." within about 5 seconds.

None of the above probably helps but might get you going in the right direction.


Worst case, I personally would use the stroker crank, stroker rods and some stock bore pistons in the original block, setup for 11.0:1 compression and put the smaller cams back in with an aggressive tune and race fuel. If the big bore is salvageable, Call Steve down at Houston Performance and start a dialog for rebuilding it. You might just be a set of pistons/rings/bearings and some machine work/assembly away from being good to go. Steve has built enough motors and rebuilt Joe Johnson's 5.4 in his 2000R. He knows what he is doing. If that doesn't work, I can get you in touch with HPP and who they are using here in DFW. They seem to split machine work between Houston Performance and a local shop in Fort Worth depending on the build. In all honesty, any shop familiar with small block chevy's should be able to build a mod motor. They are zero balanced and basic engine building techniques apply for boost or N/A.

Call me if you need to vent (214-364-0420) or need some basic advice about combos. I don't claim to know a lot about what tolerances work best for a road race motor but these motors STOCK can take a lot of abuse on track and in general. I will say you have had some bad luck since the beginning and it makes me sick to think I could be in the same boat. Maybe we can narrow down the common failure and I am leaning towards tuning??? But that's just me making a SWAG...

[jeffburch]

:idea: Richard Painter may know a thing or 2 about mod motors.
jb

[ShadowBolt]

DSS Racing is the answer

I know the former national champ in AIX uses them and Wayne has one of their engines in his AI car that has lasted for years and years (not a mod motor). SHM has not been great for several of my friends in the past. Shouldn't someone have to cover the cost of this? Unless your tune was too lean it was not your fault. I don't see lean doing all this. Some of it yes but not all the skirt damage. Looks like lots of blow-by


JJ

[AI#97]

DSS Racing is the answer

I know the former national champ in AIX uses them and Wayne has one of their engines in his AI car that has lasted for years and years (not a mod motor). SHM has not been great for several of my friends in the past. Shouldn't someone have to cover the cost of this? Unless your tune was too lean it was not your fault. I don't see lean doing all this. Some of it yes but not all the skirt damage. Looks like lots of blow-by


JJ

Jerry, hasn't it been YEARS since that car has even seen the track?! :poke:

[ShadowBolt]

DSS Racing is the answer

I know the former national champ in AIX uses them and Wayne has one of their engines in his AI car that has lasted for years and years (not a mod motor). SHM has not been great for several of my friends in the past. Shouldn't someone have to cover the cost of this? Unless your tune was too lean it was not your fault. I don't see lean doing all this. Some of it yes but not all the skirt damage. Looks like lots of blow-by


JJ


Jerry, hasn't it been YEARS since that car has even seen the track?! :poke:

Yes it has. but they still built a motor for that car that lasted for years and I know several Lightning guys around the country that have run their Mod motors and had great luck with them.
Also the 2007 AIX National champ (Chris Griswold) is a big fan. I'm sure there are other good engine builders but I KNOW these guys are good. From what I've seen and heard in the last few years I would not spend a dime with SHM. JMHO.

JJ

[cobra132]

I measured the 2 pistons with the least amount of damage exactly where manley states to measure them. I was using 100 octane fuel. There was no oil anywhere in the intake, it all had to come from below. The two pistons in the photo had the most heat related damage. Water temp 230 max and oil temp in the pan 285 max. Could be some detonation but from what I am not sure. The A/F was ok and with that much oil in the combustion chamber WTF knows. The heads, block/sleeves, crank and rods will need to be mearsured but all seem fine. Aside from the aggravation hopefully I'am only out a set of pistons, rings, bearings and machine work. Remenber this engine had about 2 dozen starts, some slow driving arround the hood, a day and a half on the dyno and 10 laps on track. Calls and emails to builder unreturned at this point. Fortunately I have the temperment of a Shaolin Monk and I do enjoy wrenghing on these cars. FMR

[cobra132]

BTY grasshoppers, I plan to install old engine this weekend. FMR

[AI#97]

I measured the 2 pistons with the least amount of damage exactly where manley states to measure them. I was using 100 octane fuel. There was no oil anywhere in the intake, it all had to come from below. The two pistons in the photo had the most heat related damage. Water temp 230 max and oil temp in the pan 285 max. Could be some detonation but from what I am not sure. The A/F was ok and with that much oil in the combustion chamber WTF knows. The heads, block/sleeves, crank and rods will need to be mearsured but all seem fine. Aside from the aggravation hopefully I'am only out a set of pistons, rings, bearings and machine work. Remenber this engine had about 2 dozen starts, some slow driving arround the hood, a day and a half on the dyno and 10 laps on track. Calls and emails to builder unreturned at this point. Fortunately I have the temperment of a Shaolin Monk and I do enjoy wrenghing on these cars. FMR

Those temps seem high but you might ping the downunder boys for their temp readings. As a point of reference, mine runs right on the thermostat at 195 water (I am removing T-stat and installing restrictor), and 230-240 oil temp in the pan with NO oil cooler. Only time mine has seen 220's on water temp was when the head gasket popped from not retorquing the head studs and after the rains at Mid Ohio and the radiator was coated in slime.

I know both of my B headed 4V's ran hot and would go down on power as the computer went into "limp mode".

Sounds like the pistons were setup "loose" to make power and had too much blowby...that will cause detonation with oil in the cylinders regardless of fuel.

good to hear you have not given up! See you at Cresson. I hope my beast is ready! :shock:

[Todd Covini]

Matt,
Sounds like you're not pushing your motor too hard. Do you push the gas pedal all the way down? :wink:

[AI#97]

.... Do you push the gas pedal all the way down? :wink:

Guess I should try that huh?! ;)

[cjlmlml]

(Frank) call richard painter

[Todd Covini]

Chris, no need to call Richard Painter, I'll explain it.

Matt...the gas pedal is the one on the far right. The further you push it down, the harder the engine will work and the faster your car will go. :roll:

[BlueFirePony]

Chris, no need to call Richard Painter, I'll explain it.

Matt...the gas pedal is the one on the far right. The further you push it down, the harder the engine will work and the faster your car will go. :roll:

LMAO...gawd I am gonna miss you guys :roll:

[David Love AI27]

.the gas pedal is the one on the far right. The further you push it down, the harder the engine will work and the faster your car will go. :roll:

so, if I cut a hole in the floor pan and push the pedal through it, my car WILL go faster??? cuz, you know, I already bent the pedal up an inch from the floor to get more travel and that didn't help a bit!!!! not kidding either, ask Hood!!!

Sorry, Frank, ADD kicked in and these guys swayed me off the topic... back to the b-day party... see ya'll in a couple of days, cept for those going to TWS this weekend....