Fast Intentions Stage 2 TT build by MA-Motorsports.

Spooler

I have a consulting fee. LMAO...

phunk

The 1/2" headstuds in DEs was the fix until the L19/CA625 made them obsolete and unnecessary hassle. The original ARP2000 material had very low torque specification and was causing headgasket failures in the 500s and 600s. People moved to 1/2" studs (including myself), and the ARP2000 material in that size we could torque to 90-105 or so, and this fixed the issues. Eventually ARP released L19 in stock thread size, and then you could build a DE with adequate clamping load on the headgaskets without the extra hassle of machining for 1/2 studs.

The blocks showed no signs of issues with oversizing for the studs. My block was tapped 9/16 then had thread inserts down to 1/2". The "machine work" for the oversizing was done with a hand drill, and the studs were so crooked that you couldnt install the heads with the studs threaded in (not my work, sent it to a member that allegedly arranged a group batch of this with a machine shop, found out when I got it back that he was doing them by hand), you had to set the head on the gaskets and then thread the studs in. That engine then lasted over 10 years without headgasket failure 600-800hp. Once it was taken to over 900whp, it didnt last much longer... although it was the old fatigued crankshaft which failed and took out the engine.

In summary, the DE 1/2" headstud debacle fixed the issue with blowing headgaskets at 500-600hp. It was made obsolete by the L19s and then CA625+. There is no evidence that a 1/2" headstud would do us any good for what is happening now, which doesnt appear to be a clamping issue, but a cylinder movement/support issue.

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Spooler

So what are your thoughts on the Darton MID sleeves Phunk? Is this the right move. I am still researching on this subject.

Elmo370z

If sleeves are the answer, who or what shops to install them? How do we know if they installed correctly?

Spooler

Oldy but goody. Triples, compound turbos.

phunk

I havent really formed an opinion on wet sleeves in the VQ. For a long time I didnt think they were worth the risk of problems, since nobody was breaking cylinder walls open or running enough power to have issues. In 2003 I did build myself a sleeved block, AEBS did the sleeves and installation. That engine made it about a day or two after tuning to 670whp I think before it blew the headgaskets, but it also had the old m11x1.25 ARP2000 that failed everyone. So who knows which was the culprit, or maybe both. That was when I followed up with the 1/2" headstud build. After that I never really considered them again, and assumed that even if they did hold up for a while, they probably werent the right setup for a long life engine that someone wanted to see like 4+ years out of. I feel like you are setting yourself up with some individually very strong cylinders, but that they are floating around in a compromised chassis (block) that is tweaking and twisting and probably not going to be able to hold those sleeves stationary forever. But what do I know, maybe they are the answer. I would trust them more if they were 1 solid chunk per bank, so each cylinder is supporting its neighbors as they hand off cylinder wall side loads back and forth, but that would be a lot more expensive to produce. What I wanted to do with my wet sleeved VHR was do a half-fill to try and give them more support to the block and to one another. My machinist didnt think he could pour in the epoxy through the small holes in the wet sleeves well enough to do a nice even job.

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Spooler

Yeap, that is my question. How long will it last and what will happen over time. Will the sleeves stay put? Will the block yield and crack?

Elmo370z

https://youtu.be/1pV_tLbZY0A

Why y’all drag racers need to find yourself a good tuner and run a stand alone

Spooler

Is that your first taste of compound turbo charging? It is very common in the diesel world. I was dang close to putting a setup on my truck. LOL

Elmo370z

JUst the depth of detail

Rusty

Yeah, compounds been around a long time. Worked on a few Elliott PAP compressor packages that had 3 of them.

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浪人 - 殺し屋
"The Difficult Anytime, The Impossible By Appointment Only"
http://www.the370z.com/members-370z-...o-journal.html

solidus

My Titan XD Cummins is a compound turbo setup. Even though Nissan can kiss my a$$.

Rusty

Some ford super duty's are compounds too. Depending on year.

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浪人 - 殺し屋
"The Difficult Anytime, The Impossible By Appointment Only"
http://www.the370z.com/members-370z-...o-journal.html

GeauxTigers1

Damn Spooler so sorry to hear man. I came on here to see what Crazy flywheel/clutch combo you had told me about only to see this. Scares the **** out of me man with the 22psi setting I have on mine. Think even with the built block, closed deck I should keep boost levels low if I want to last. Limiting it to 15psi today is a sad day brother. Hope all is well and you’re back again soon!

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Fast Intentions Kit Stage 2 #076 2017 Twin Turbo 370z Nismo. JMS Built Block, Closed Deck 874whp, 803lbs Tq e85 Ecutek Tune

Spooler

Crap happens, you should be good to 17psi if you have ARP 625 head studs and a close deck block. I have a couple of options I am looking at. Nobody knows how long anything will last due to the fact that they don't drive them for whatever reason. I may be back sooner than you think I hope.