Don't rattle em with knock or burn em bringing in torque to fast too low rpm wise.
Keep the IATs down and you should be fine. People play with fire on stock hyper pistons with decent luck.
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Don't rattle em with knock or burn em bringing in torque to fast too low rpm wise.
Keep the IATs down and you should be fine. People play with fire on stock hyper pistons with decent luck.
Probably just going to run them at this point. No turning back now. The LS9 (forged) and LSA (cast) pistons both have thinner top lands at .217 and .219 but seem to do just fine in OEM apps (although they have no valve reliefs). Being that this is a 383 and the top end will be decent, I'm definitely not going to need as much boost as before so I'm not gonna worry about it. I don't think any additional power beyond my goal will be useable in a stick car anyway so I'll refrain from amping up the boost when it's done.
Need to figure out where to get this thing tuned too... The 24x makes things much less complicated. Who's everyone using? ECS?
I decided to ditch the Trick Flows a little while ago. They needed more work than I bargained for so they gotta go. Picked a brand new assembled set of AFR 210 Eliminators instead from a build that was being parted out. The only problem is that the springs included are total overkill for my setup (220/475 seat/open) and have to be swapped out for something that won't beat the piss out of my valvetrain but still handle boost.
The crank came home today after almost 2 months. Gonna mic it again tomorrow to be sure everything is good. It was only polished so it should be fine.
Tune time performance in NJ did mine and will be doing Blackbirdws6, I was very pleased with them.
Alright, there are a few different guys I was considering so I will keep them in mind. Was really wondering how much it would cost to have Byran Herter do the tune but I don't think he's in the area too ofter for dyno tunes (other side of PA). Was thinking the final tune will be speed density in closed loop. Will keep the stock MAF for NA.
Rods came in today. Pretty much the last parts I needed for the shortblock work to begin so now it's time to get things machined. Will be making a few calls next week to get the ball rolling.
I know you said you didn't plan on pushing yours hard but I was running 14# on pump gas, 9:1 compression, on an srp 4032 (pn 148750) intercooled with 75° iats, no meth, running 18° of timing, high 10's on afr, and still melted a slug. Hopefully the Mahle has a better ring land design than the srp. After talking with mark from probe, I have decided to go with their 2618 pistons with .225 tool steel wrist pins. Your setup is going to make more steam than you think with those heads and the right cam.
What was the dish on the srp?
edit: Just noticed the part # and it's -31cc, holy crap
Found a picture...
http://i1205.photobucket.com/albums/...116_211442.jpg
I wonder what the top land is on these.
I noticed a lot of the failed SRP pistons with cracked lands I was looking at have a dish that gets deep too close to the edge and makes the space behind the top ring groove very thin. Same goes for the valve reliefs. I chose the Mahle early on because the dish is shallow and looked gradual.
http://ltxtech.com/forums/attachment...0&d=1390634130
Wasn't the tune on that motor jacked up? I kinda changed my mind about using these after seeing a post from Mark O'Neal of Probe...
http://www.speedtalk.com/forum/viewt...e491ca#p214011Quote:
If everything is right in the tune up it doesn't matter how we make the pistons.
If something is wrong in the tune up it doesn't matter how we make the pistons.
There are a lot of failures on the srp pistons. However I dont think its so much the piston to blame as nuch of the ring gap. Golen uses srp pistons exclusively in their boosted engines and claims to add boost and you have 750hp. If you call srp and ask them, they will tell you their 4032 alloy is only good to 750hp. Above that the recommend their extreme duty (2618) line. I heard that from the horses mouth.
The previous owners tune was jacked up in the pcm on the car the engine was originally in. Very lean. I bought the engine, replaced the pistons with the exact same pn, file the rings for boost and have every datalog for ever time it's been driven. I've had 5 accel emic (tuners) look at my logs and tune and they all agree I was running safe rich and conservative ignition. It still melted a piston as seen on a scope. Initially i felt that having the opti come apart on its first wot run could have caused MY damage (melted crown, not the cracked ring lands, thst i know of yet) due to the ignition possibly being over advanced. However after talking with others and thinking about it logically, it would have retarded the timing as it came loose. So i wouldnt expect detonation from that. Now in my case I just have one piston melted, the argument could be raised that the injector failed. After I pull the head I'll know for sure.
And you are very much correct in that a sharp area or one with little material will melt away easier than a piston with a flat top or non dish design. Prior to buying these probe pistons I looked my ass off to find a set of flat tops that I could run in an undecked block but the problem with flat tops is that they are not typically made for higher cylinder pressure.
I asked around and was told it to run meth beyond 10lbs with ~9.3:1 compression, 93 octane, and an intercooler. The techs at Mahle told me I should be fine up to 15 with good tuning but I would definitely run out of injector before that.
Curious to see what went wrong with this SRP.
It's crazy what you'll be told by people in the industry when it comes to compression ratio, boost, and what is safe. Feast your eyes on this hot garbage...
I asked if my accel dfi will run low impedance injectors told this very well known tuner about my setup and this was his reply
"Yes the dfi can run either low or high impedance injectors. But the key to what you have told me below is this "I understand no piston will survive a poor tune"
Now that being said I don't know anymore than what you have told me here. But... If your melting pistons your tune is in left field.
#1 Your wide band is ether calibrated wrong or your not paying any attention to it.
#2 Delphi injectors are junk don't use them.....period....
#3 Sounds like your running injectors static or over pressure. Duty cycle must be NO more than 87%
#4 Fuel octane must be appropriate for final compression developed.
So before you ran 93 octane on 9 to 1 plus 14lbs = 17.6 to 1
Now you want to run PUMP E-85 @ 10 to 1 plus 18lbs = 22.2 to 1
Both these combinations will have abnormal combustioncharacteristics to make any power and will get hurt doing so.
PUMP E-85 is Ethanol and 87 octane blend.Capableof sustaining 11.5 to 1 MAX
We blend an E-85 using 116 race fuel that sustains 13.5 to 1. (hold Suzuki records)
That being said your old setup needed 116 to make proper power WITH the correct injector. Knowing no more than I do I can assure you your going to hurt parts with these combo's. Just because so in so has done it, doesn't make it right nor help it live. Do it the right way the first time."
So I guess by this professionals standards, you better break out the c16 lol