Some Interesting things about VQ
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Some Interesting things about VQ
I just got off the phone with PFI, I bought the turbo kit finally!! I got the 60-1 upgrade just like Nigel. PFI is awesome, they have the best prices and the most accessories.
Anyways right after that I got a call back from my father, who is good freind with the owner of Probe Industries. Im having them make 9:1 forged pistons, and maybe get some aftermarket rods. So he tells my dad that the rods are already forged, and that they are very very strong rods. The only thing they would do is maybe polish and go with some better bolts.
He also told him that the I30 engine is actually different thatn the Maxima engine, and of course I started laughing and was like BS. I said they are the same engine, and he assured me that they have minor differences in some components of the engine becuase Probe double checked some specs. I dont know if this is common knowledge or if Probe is wrong ( I doubt that)?
Anyways right after that I got a call back from my father, who is good freind with the owner of Probe Industries. Im having them make 9:1 forged pistons, and maybe get some aftermarket rods. So he tells my dad that the rods are already forged, and that they are very very strong rods. The only thing they would do is maybe polish and go with some better bolts.
He also told him that the I30 engine is actually different thatn the Maxima engine, and of course I started laughing and was like BS. I said they are the same engine, and he assured me that they have minor differences in some components of the engine becuase Probe double checked some specs. I dont know if this is common knowledge or if Probe is wrong ( I doubt that)?
Originally Posted by JAY25
so all we need is pistons to get lower compression?
Yeah, I will find out exactly what is different or what he meant.
To lower compression all you need is to change your piston height or get a thicker head gasket.
The rods are important because you might "throw a rod".
A buddy of mine said that I will not throw a rod because the RPM length on the VQ is very short where some hondas go up and beyond 10,000 RPM, which is why rods are very common for hondas. Either way, the head of Probe said that the stock rods are already forged and there is no need to go aftermarket.
Does anyone know where to find detailed specs on the VQ motor like what the internals are made of?
To lower compression all you need is to change your piston height or get a thicker head gasket.
The rods are important because you might "throw a rod".
A buddy of mine said that I will not throw a rod because the RPM length on the VQ is very short where some hondas go up and beyond 10,000 RPM, which is why rods are very common for hondas. Either way, the head of Probe said that the stock rods are already forged and there is no need to go aftermarket.
Does anyone know where to find detailed specs on the VQ motor like what the internals are made of?
Originally Posted by BrianV
Yeah, I will find out exactly what is different or what he meant.
To lower compression all you need is to change your piston height or get a thicker head gasket.
The rods are important because you might "throw a rod".
A buddy of mine said that I will not throw a rod because the RPM length on the VQ is very short where some hondas go up and beyond 10,000 RPM, which is why rods are very common for hondas. Either way, the head of Probe said that the stock rods are already forged and there is no need to go aftermarket.
Does anyone know where to find detailed specs on the VQ motor like what the internals are made of?
To lower compression all you need is to change your piston height or get a thicker head gasket.
The rods are important because you might "throw a rod".
A buddy of mine said that I will not throw a rod because the RPM length on the VQ is very short where some hondas go up and beyond 10,000 RPM, which is why rods are very common for hondas. Either way, the head of Probe said that the stock rods are already forged and there is no need to go aftermarket.
Does anyone know where to find detailed specs on the VQ motor like what the internals are made of?
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Originally Posted by spanishrice
Hmm, i wonder what the differences are? Where did he check this information at? Also how much are the pistons going for?
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Well some info I found about the 300zx rods but no info on VQ rods yet:
http://www.sportcompactcarweb.com/pr...scc_proj300zx/
Scroll down half way to The Rods:
"Although the stock forged steel, bronzed-bushed, floating wrist pin, Nissan rods are very strong and really are akin to many manufacturers' racing rods, we opted to go to an improved real racing rod for peace of mind. The stock rods are very strong and have been used in 600-hp engines with no problem before, but the cost of failure is so high, we do not want to take any chances."
http://www.sportcompactcarweb.com/pr...scc_proj300zx/
Scroll down half way to The Rods:
"Although the stock forged steel, bronzed-bushed, floating wrist pin, Nissan rods are very strong and really are akin to many manufacturers' racing rods, we opted to go to an improved real racing rod for peace of mind. The stock rods are very strong and have been used in 600-hp engines with no problem before, but the cost of failure is so high, we do not want to take any chances."
Joined: Dec 2000
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From: Near Archer High School, Ga
I am planning to build my engine by next summer if my sh!tty azz daily driver quits breaking down. Next break down and I am dropping another engine in that sucker
.
going on along, I may purchase some pistons and rods and ARP studs for the block I currently have downstairs and up the boost to what 15PSI should put me half way there with the big dogs. Cant beat them but at least keep up
.going on along, I may purchase some pistons and rods and ARP studs for the block I currently have downstairs and up the boost to what 15PSI should put me half way there with the big dogs. Cant beat them but at least keep up
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I am now 90% sure that VQ30DE rods are in fact forged, and I have a feeling that VQ30DET rode are the exact same as the VQ30DEs'.
The SR20DE shares the same exact rods as the SR20DET and stock rods are strong enough for them to keep.
http://www.se-r.net/about/200sx/scc/june98/june.html
"The factory crank and rods were left pretty much stock. Nissan makes these parts from forged steel unlike the weaker cast iron that most American car companies use. The crank has generous rolled fillets and lots of journal overlap so it is a stout unit as-is from the factory. The rods feature meaty radii and spot faced bolt registers unlike the weak, stress riser inducing broaching technique used by the big three. The rods come with beefy 9mm bolts. Finally the crank and rods are subjected to a severe shot peening. Shot peening stress relives the parts and forms a tough micro-forged grain structure on the surface of steel parts which helps prevent cracks from forming. Shot peening increases fatigue strength by over 100 percent in most cases. The main caps are tied together by a substantial aluminum girdle that helps the block resist flex and prevents the main caps from shifting under load. All this is straight from the factory! Most of the high-grade rods and crankshafts that the big three offer in their motorsports department catalogs have these features, but Nissan has them as OEM box stock."
The SR20DE shares the same exact rods as the SR20DET and stock rods are strong enough for them to keep.
http://www.se-r.net/about/200sx/scc/june98/june.html
"The factory crank and rods were left pretty much stock. Nissan makes these parts from forged steel unlike the weaker cast iron that most American car companies use. The crank has generous rolled fillets and lots of journal overlap so it is a stout unit as-is from the factory. The rods feature meaty radii and spot faced bolt registers unlike the weak, stress riser inducing broaching technique used by the big three. The rods come with beefy 9mm bolts. Finally the crank and rods are subjected to a severe shot peening. Shot peening stress relives the parts and forms a tough micro-forged grain structure on the surface of steel parts which helps prevent cracks from forming. Shot peening increases fatigue strength by over 100 percent in most cases. The main caps are tied together by a substantial aluminum girdle that helps the block resist flex and prevents the main caps from shifting under load. All this is straight from the factory! Most of the high-grade rods and crankshafts that the big three offer in their motorsports department catalogs have these features, but Nissan has them as OEM box stock."
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Originally Posted by JAY25
Question, how many boosted guys here on the org have thrown a rod? So far I only seen damaged piston cracked into pieces.
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Originally Posted by spanishrice
Are you going to give me an estimate on the pistons, so that guy can maybe make a secodn set for me, thanks.
Joined: Jun 2003
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From: San Fernando Valley CALI
Originally Posted by I30tJim
I don't think anyone has ever thrown a rod.
think the ecu showed that the engine crapped out at some crazy RPM... like 8500K or something...
he calls my other buddy up, the niss tech, and was like, "it just stopped running".... LOL...
Originally Posted by JAY25
Question, how many boosted guys here on the org have thrown a rod? So far I only seen damaged piston cracked into pieces.
im on my 3rd motor right now, but i have never broken a rod. Its always the pistons that gets fried. even at 15+psi i have never thrown a rod. witin in about 15seconds of doing 15+psi my pistons were destroyed. hehe. Vq rods are ver sturdy. I believe we wont need to upgrade our rods if someones building their motor.
Rods are cast not forged, they actually have casting marks. Pistons are pressure cast, they are pretty tough.
A VQ30 is a VQ30, no difference between I30 or Max.
I agree that if you are going to do pistons to lower CR do rods also. The time and/or money to get to the rods will already be spent. If your talking about under 400whp you should be ok as long as its tuned good. But if you wanna run it hard, pay up.
A VQ30 is a VQ30, no difference between I30 or Max.
I agree that if you are going to do pistons to lower CR do rods also. The time and/or money to get to the rods will already be spent. If your talking about under 400whp you should be ok as long as its tuned good. But if you wanna run it hard, pay up.
Originally Posted by qnpark8282
im on my 3rd motor right now, but i have never broken a rod. Its always the pistons that gets fried. even at 15+psi i have never thrown a rod. witin in about 15seconds of doing 15+psi my pistons were destroyed. hehe. Vq rods are ver sturdy. I believe we wont need to upgrade our rods if someones building their motor.
What are you doing for ignition timing control? Think detonation could be the reason you are cracking pistons?
How about fuel for 15psi, what set up are you running?
Not calling BS, just wanting to look at you set up from a "why did you crack a piston" perspective. The bost psi level should have very little to do with it, prolly tuning, or raw power.
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Originally Posted by MardiGrasMax
Rods are cast not forged, they actually have casting marks. Pistons are pressure cast, they are pretty tough.
A VQ30 is a VQ30, no difference between I30 or Max.
I agree that if you are going to do pistons to lower CR do rods also. The time and/or money to get to the rods will already be spent. If your talking about under 400whp you should be ok as long as its tuned good. But if you wanna run it hard, pay up.
A VQ30 is a VQ30, no difference between I30 or Max.
I agree that if you are going to do pistons to lower CR do rods also. The time and/or money to get to the rods will already be spent. If your talking about under 400whp you should be ok as long as its tuned good. But if you wanna run it hard, pay up.
I just spoke with an engineer at Probe and he said that the rods are forged.
The "casting marks" are not from a cast, the difference is that a cast will have a crisp line down the center where a forge will have a broad line down the center. Im sure that they are right because they make forged pistons for a living.
Originally Posted by I30tJim
I just spoke with an engineer at Probe and he said that the rods are forged.
The "casting marks" are not from a cast, the difference is that a cast will have a crisp line down the center where a forge will have a broad line down the center. Im sure that they are right because they make forged pistons for a living.
The "casting marks" are not from a cast, the difference is that a cast will have a crisp line down the center where a forge will have a broad line down the center. Im sure that they are right because they make forged pistons for a living.
Sorry, I disagree.
yeah if I'm correct as far as Maximas go...the VG30 in the 3rd gen was the last Maxima with forged rods(maybe the VE as well??) but seriously don't remember the VQ having anyhting more than cast
I am going to steal your thread, does anyone know the size of a maxima pisto? i was thinking about maybe using a piston from another car. Does anyone know the bore on our cars and how much more we could bore the block without it losing structural stability?
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Yea or maybe a rod from another car.
Anyone know if it would be possible to run other Nissan forged parts like from a Z or Sr20? Or maybe even get pre made custom rods that fit our oem specs? I can't find any specs on the VQ for the life of me.
Anyone know if it would be possible to run other Nissan forged parts like from a Z or Sr20? Or maybe even get pre made custom rods that fit our oem specs? I can't find any specs on the VQ for the life of me.
Ya i have been trying to find specs on the engine, I searched for about an hour last night and could not find anything. I was not thinking about using pistons from another nissan though......
Originally Posted by IwANnAMaX96
