Oval Chamber Pistons

MarkBroviak

DMax Junkie
Vendor/Sponsor
May 25, 2008
2,129
446
83
Danville Indiana
I appreciate the replies. My motor will be torn down shortly. Had a failure of some kind. I know it wasn't the pistons, but I am always looking to build bigger and stronger if I have to go into the motor.

My truck gets used pretty hard. It went 50k with 300+ 1/4 mile passes at 800ish hp, and 20k of that was towing. So the general consensus is these are stronger than the normal mahle race cast piston?

Yes Verlon, that's is how this design arrived. Mr. Fingers is way smarter than I am and has all of my confidence so if he tells me that they are stronger and I need to try and prove otherwise, that's my goal! It's all in how you make your power that will dictate longevity. We just finished an lly build on a twin truck that cracked 6 pistons and bent all the rods with stock injectors& cp3 no lift pump and had 59,000miles on it. It only dynoed 525hp with the tuning that was in it when it failed. I'm sure the tuner thought it was conservative but the results say otherwise. I plan on running these pistons in my railcar when I put it together.
 

jkholder09

New member
Jan 8, 2012
1,188
0
0
Maryland
I think the difference in sound comes from the fuel burning outside the bowl. It always seems like the crackling and popping happens with big pulsewidth, dodge ford and chevy, and that with an oval bowl this sound is just intensified. It sounds really spectacular, I am considering buying the pistons just for the sound!!!
 

Fingers

Village Idiot
Vendor/Sponsor
Apr 1, 2008
1,715
86
48
White Oak, PA
I think the difference in sound comes from the fuel burning outside the bowl. It always seems like the crackling and popping happens with big pulsewidth, dodge ford and chevy, and that with an oval bowl this sound is just intensified. It sounds really spectacular, I am considering buying the pistons just for the sound!!!

Interesting theory. The quench area on these pistons is actually smaller than "normal" pistons. So there is less space for fuel to burn outside the bowl.
 

Fingers

Village Idiot
Vendor/Sponsor
Apr 1, 2008
1,715
86
48
White Oak, PA
Another set out the door.

attachment.php
 
Last edited:

jkholder09

New member
Jan 8, 2012
1,188
0
0
Maryland
Interesting theory. The quench area on these pistons is actually smaller than "normal" pistons. So there is less space for fuel to burn outside the bowl.

Yeah thats what you were thinking the quench area above the pins runs cooler making that area less likely to crack. I think its a good idea also looking at them.
Maybe its just chasing the piston down the hole with fuel that makes them sound different with big pulsewidth than.
I suppose the sound of the oval piston is still a mystery???
 

Fingers

Village Idiot
Vendor/Sponsor
Apr 1, 2008
1,715
86
48
White Oak, PA
Getting additional stock in.

I will now have 0.040", 0.020", and STD bore cast piston blanks in stock.

Most sizes of Forged piston blanks are available with a short delay. Just ask.
 

MarkBroviak

DMax Junkie
Vendor/Sponsor
May 25, 2008
2,129
446
83
Danville Indiana
Just sent two trucks home this week that we built and both have 15.5:1 oval bowls. Both trucks are just plain rowdy! One is a 2.5 VGT workstock truck/daily driver and it produced 728hp 1489ftlbs on a stock lly compressor cover untouched! They are rediculously loud and responsive. The other was a S475 cast 2.6 truck in the 800hp range . Both customer's were tickled to death with how their trucks turned out. More happy customers, thanks!
 

Hot COCOAL

May the farce be with you
Jun 9, 2012
4,433
0
0
Just sent two trucks home this week that we built and both have 15.5:1 oval bowls. Both trucks are just plain rowdy! One is a 2.5 VGT workstock truck/daily driver and it produced 728hp 1489ftlbs on a stock lly compressor cover untouched! They are rediculously loud and responsive. The other was a S475 cast 2.6 truck in the 800hp range . Both customer's were tickled to death with how their trucks turned out. More happy customers, thanks!

Mark, out of curiosity, and for all the other fans out there, what is the bill for a job like the last two?

how much would it cost if i brought in my truck to have you upgrade my 4094 to a vgt 72 , and also install pistons and rods (of the fingers variety with carrillio's)and of course all the finer details. I know there are many variables to consider, but if you would just throw a ballpark # out for a rig that already haas everything else done and is ready for such upgrades.I will provide the injectors, 100% exergy's

The turbo i have was purchased new and has only 6k miles on it and the cylinder bores still have factory crosshatching, inspected 6k ago when the arp studs went in. I would want the block to be completely gone through and girdled.I would be shooting for a solid 800whp with the ability to go bigger later...sounds all too familiar im sure.

I am really getting close to being ready, the rear end fiasco set me back a couple months, only cuz i decided to regear my truck at the same time i put in the eaton trutrac, so probably looking at july...it would be nice to have a figure in my head for a goal for the next and final chapter of my "build" saga.
 

MarkBroviak

DMax Junkie
Vendor/Sponsor
May 25, 2008
2,129
446
83
Danville Indiana
Mark, out of curiosity, and for all the other fans out there, what is the bill for a job like the last two?

how much would it cost if i brought in my truck to have you upgrade my 4094 to a vgt 72 , and also install pistons and rods (of the fingers variety with carrillio's)and of course all the finer details. I know there are many variables to consider, but if you would just throw a ballpark # out for a rig that already haas everything else done and is ready for such upgrades.I will provide the injectors, 100% exergy's

The turbo i have was purchased new and has only 6k miles on it and the cylinder bores still have factory crosshatching, inspected 6k ago when the arp studs went in. I would want the block to be completely gone through and girdled.I would be shooting for a solid 800whp with the ability to go bigger later...sounds all too familiar im sure.

I am really getting close to being ready, the rear end fiasco set me back a couple months, only cuz i decided to regear my truck at the same time i put in the eaton trutrac, so probably looking at july...it would be nice to have a figure in my head for a goal for the next and final chapter of my "build" saga.

You can be anywhere from $12K up to 30K depending on parts and labor. The main stream average is close to $20k for a 700-1000hp build that is streetable. It is when you get into the custom parts that really jacks the price up. Hope this helps!
 

Hot COCOAL

May the farce be with you
Jun 9, 2012
4,433
0
0
You can be anywhere from $12K up to 30K depending on parts and labor. The main stream average is close to $20k for a 700-1000hp build that is streetable. It is when you get into the custom parts that really jacks the price up. Hope this helps!

Yes, that helps a ton, thank you for the response!:hug:
:happy2:

I am guessing my needs will cost upward of 15k.I will have alot of the supporting mods, if not all, already on the truck or with it, just need some "guts" and a little fortifying of the block ,but if i decide to get into the heads and valvetrain, 20+ will probaitbly be the outcome

I hope to be talking to you personally this summer, thanks again
 

MarkBroviak

DMax Junkie
Vendor/Sponsor
May 25, 2008
2,129
446
83
Danville Indiana
Spray pattern in my motor with these pistons!

I took my heads off for some testing of new heads and thought I would share the pictures of my pistons after a few thousand miles of wear and tear. Pretty interesting to say the least!
 

Attachments

  • marks phone 095.jpg
    marks phone 095.jpg
    195.2 KB · Views: 404
  • marks phone 096.jpg
    marks phone 096.jpg
    189.2 KB · Views: 354
  • marks phone 097.jpg
    marks phone 097.jpg
    194.9 KB · Views: 355

MarkBroviak

DMax Junkie
Vendor/Sponsor
May 25, 2008
2,129
446
83
Danville Indiana
No coating, I did polish them and I think that is why they look the way they do. If I put brakleen or carbclean on the rag they wiped right off. I just wiped them off with a shop rag for the picture.
 

Slammed2007Lbz

Super Spicy Tunaz
Feb 1, 2009
1,118
0
36
NE Ohio
Is that good spray pattern? It looks like it is all staying contained in the bowl for the most part which is what you want correct?
 

x MadMAX DIESEL

<<<< No Horsepower
Dec 30, 2008
7,535
1
38
34
Lexington, Ky
Yes that is correct. I was thinking the samething Josh. I dont think that would be a good sign if a coated piston flaked like that. It would cause the heat absorbed by the piston to be inconsistant. I wouldnt think that would last very long with arbatrary hotspots, maybe start to crack?