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Discussion Starter #1
after “Completely“ finishing my spec v build from A to Y... one of my cylinders drops compression while on the Highway omg😭... there’s so much more that I want to add to the subject but this is about wanting to know what experiences anyone has or has had with the 2JRacing QR25DE fully built turbo ready motors? How reliable, does it really hold what they say it can hold and for how many years with their motor live up to the name? We allllll know about this motors bad habits like the dry start noise and the phaser is always a mystery hit or miss, the cam position sensor goes out every one or two years and the countless deletes and mods it needs to perform without failure of substandard parts... I’ve got one of the nicest Spec V in Florida and I’m doubting this motor unless 2JRacing builds these phenomenally and bullet proof. Is their QR25DE turbo built motors with the $4k? Will it lassssst? Yes the tune I know but I’ve had my motor on 20lbs reliable for 2 yrs and took it down to 16lbs once it became a show car and I only baby it and it dropped a cylinder after 4 yrs. is that the life span of a turbo build? Should I fix this problem and keep my motor or should I drop something else in or is the 2J QR25DE the way?
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I got a 2j short block. Was everything it said it was. Installed, ran like a champ til I blew a head gasket. My shop installed the head, so it wasn't a 2j issue, and I also boosted a high compression block, so shit was gunna happen. I've heard some horror stories, but usually it comes down to accountability. Also if 2j does the work, or if another shop does, I'd ask questions about, well what happens if shit hits the fan.
 

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20 lbs with an AFC? 😯 I am surprised there is an s on the end of year, honestly. Get it turned up well and you shouldn't have a problem with a built engine. Also ditch the light weight crankshaft pulley.
 

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Yea 10:1 compression lasted 3yrs 20lbs hard driving and then another 3yrs 17lbs weekend fun but I was redoing the whole car during that time so it wasn’t an entire 3 yrs, I’ll call it 2 yrs bcs of down time. did I get all the engine life that I could get or did it die early? Stock block, unbalanced crank shaft, forged inners, springs & cams,.. just happened today so I don’t know if it’s piston related or head related... no mixed fuels. I removed all the plug cables and when I cranked it I could hear that one cylinder was off rhythm. But I made it home 💪.

so your fail wasn’t even the block... was it a sleeved block or a sealed deck? I believe they’re 700hp claimed block is a sealed deck or maybe just sleeved but before I drop $4K..,, you feel me lol.,
 

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MTRapuzz.. forged internals can hold that no problem. Also harder springs so there’s no discrepancy. The SAC is a good combo with the 2J modded ecu and using a maf from the v6. The only weak point is stock sleeves but I’m not having mixed fluids so it’s not a cracked sleeve or a gasket or a hole in the block, at least I don’t think lol🤔 I’m thinking it might be a broken spring. It’s not a bent valve bcs I drove it home. But one cylinder is low compression.
 

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Discussion Starter #6
These are the only pictures I can find of the internals. It’s all besides the point... The matter is.... worth fixing or keeping this setup going or... is the 2J fully built motor
(long block) going to last longer than this build did before failure? Would anyone of you buy a 2J turbo built long block if you were in my position? How much does your car mean to you vs what’s ever?
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MTRapuzz.. forged internals can hold that no problem. Also harder springs so there’s no discrepancy. The SAC is a good combo with the 2J modded ecu and using a maf from the v6. The only weak point is stock sleeves but I’m not having mixed fluids so it’s not a cracked sleeve or a gasket or a hole in the block, at least I don’t think lol🤔 I’m thinking it might be a broken spring. It’s not a bent valve bcs I drove it home. But one cylinder is low compression.
Unfortunately, 2J tunes are notoriously bad. You should have an actual dyno tune and not just a cookie cutter reflash and AFC tune drift.
 

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Discussion Starter #8 (Edited)
@ puzz...I tune my own $#¡t lol 😁 That AFC has done me wonders along with the g35 maf, You know the qr25de doesn’t have options like hondata and it’s not worth throwing down a stand alone over this motor, I’d build something else for all that come on man.. for what it’s worth the 2J modded ecu gives the MAF more room before maxing it out. A turbo will blow out the standard maf on a stock ecu like a candle. The main subject is are the 2J long block turbo built motors worth the money? Or is a QR25DE always going to be a QR25DE? I’m looking at $4k... I got about 5 yrs out of my build. If theirs isn’t going to live past that then the answer is maybe it’s not worth the money and I’ll keep my build.
 

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Discussion Starter #9
I’ll post more pictures when I get time to open up the motor again and see what when wrong. Thanks Puzz & Tritton I’ll come back around at God speed lol 👌
 

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You need to pull the valve cover off see if it corresponds with the cam lobe's position of what you are showing us. With that being said, I did not see what cams are you are running and will look again.

Long story short you are going to have to pull the head, if anything the cams need to be pulled to look at the valve retainers... but I'm getting ahead of my self and you may need to check the valve clearance.

Unfortunately you wasted a lot of time by not removing the valve cover over all.
 
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Discussion Starter #13
The first time I pulled the plug wasn’t that bad looking. Timing was all in place, no skip... HOWEVER even I placed the plugs in and cranked the motor, IT RAN FINE! nooo problems except for a random miss every 30 seconds at idle. It drove normal until it warmed up. It would barely miss when accelerating from a dead stop at low rpm but it had power and ran quiet. I did a short acceleration test and as one would expect, compression GONE spark plug electrode bent. Pull over and fix and it made it home. Sounds to me like a broken valve spring, and additional damage as a product of cause and effect.
The motor was built 6 yrs ago and it’s been at average 17-18 psi and I enjoyed every minute. It was inevitable and to last 8 yrs is more than expected so I’m not feeling bad about myself.
If I can get the heads rebuilt for $200-$250 and there’s no bore damage or ring/bearing damage I’ll do that and slap it back on. But if I need a full rebuild....🤔 it might not be worth it bcs of the cost and considering you can get a professionally built and REVISED/UPDATED QR25DE... I’ll post as I go.
 

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Have you taken off your upper intake manifold as it looks like that might be butterfly screw damage to the spark plug?
 
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Ah a butterfly screw yes. Also if you have a camera to put in the cylinder. Whatever it is lit likely scored the cyl walls or valve seats so bad that its losing compression.

Sorry man
 

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Discussion Starter #17
@sus-spec.. I HOPE it’s just heads... the butterflies been removed, but it’s strange bcs after looking at the plugs at home, I put the plugs back in and the car ran perfect... it was missing at idle but that went away in a few seconds. I shut off the motor and cracked it without spark and the compression came back! I drove it and it ran perfect 🤷‍♀️... I went under boost it was ok, went under a tiny bit more boost and it happened all over again! This time plug was all scratched up and once again smushed shut. Pulled over, pulled out plug and corrected it... on startup the sound of low compression on one of the cylinder appeared again.. I drove it home and it ran fine except for the random missing which came and went sporadically. “” I feel as if I have a broken intake spring””
 

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Discussion Starter #18
OK so to hypothesize the symptom I am going to say that it is a broken intake valve spring. This is after weighing out all the variables and due to the fact but the car runs fine until I go under Boost. that’s where the spark plug gets smashed again and I also have a problem with compression loss and the compression actually returns once I correct the spark plug and I drive it for a little bit but compression comes back slowly. So it’s not a spun bearing and it is not a damaged piston ring. The problem has variables to it and the only thing I can think of is a broken spring because the tension changes as the spring vibrates and turns. I have not opened up the motor because I want to buy a fully turbo built motor from 2Jay racing and I get a $500 core for the current motor I have but I don’t know what conditions they expect it to be in so I am researching that at the moment.
 

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Yeah I think there has to be something in the cylinder physically hitting the plug. Springs are allowed to turn between head and bucket. That still wouldnt matter. It might just be getting beat up over time and eventually closing. It looks like something is hitting it at all angles.

Are you using cast aluminum pistons or forged?
 
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