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Just bought a used VQ37 awd engine from a yard off a 2013 G37x that I am currently stripping down to just the block to be machined and freshened up.
I plan on getting Wiseco forged piston heads with Brian Crower rods and I'm wondering if I should over size the piston heads.
The reason I ask is not because I want to increase the displacement but instead because I read after getting the cylinder walls machined they could be shaved down during the cleaning process, so I'd like to keep a low compression ratio for the AAM twin kit I have while also making sure the pistons are going to fit properly.
Any help and information will be greatly appreciated so thanks in advance.
Stock ECU and ecutec or standalone?
either way, low compression should NOT be your goal.
besides, a "cleanup" or even oversized (stock) pistons would not change the comp ratio enough to sooth detonation issues prevalent with past fuel/timing management.
and don't bother "cleaning" the bores till you have new pistons in hand for the machinist to measure.
if your power goals are high enough, sleeving and/or a block guard might be the way to go.
Stock ECU and ecutec or standalone?
either way, low compression should NOT be your goal.
besides, a "cleanup" or even oversized (stock) pistons would not change the comp ratio enough to sooth detonation issues prevalent with past fuel/timing management.
and don't bother "cleaning" the bores till you have new pistons in hand for the machinist to measure.
if your power goals are high enough, sleeving and/or a block guard might be the way to go.
Sorry I didn't get back sooner, I haven't had time to comeback to this thread till now.
To answer your questions I'll be keeping a stock ECU with ECUcutek as I haven't found a standalone ECU for the G37 anywhere I've tired looking. My power goals I'd say are fairly high (roughly 600hp to the wheels). I do intend on sleeving my block with Daton sleeves aswell as using the Wiseco/Eagle pistons and rods
I wasnt too sure on what a "good" compression ratio for boost would be and I am still fairly new to anything in depth like that, I figure the normal 10:1 would be ideal for boost but I really am unsure.
The only reason I thought I may need to oversize the cylinder walls wasn't from a want to do so but rather it may have to happen during a cleanup if the engine has alot of debris or carbon build up inside the block, Im sure alot of the VQs by now (atleast any I can buy used) have really seen better says and have seen many many miles. My plan is to buy a X model longblock with the transmission and tear it all apart by hand to learn the ins and outs while also saving money instead of buying a remanufactured VQ from somewhere.
Hope that answers some of your questions and give you a better idea of my plans, anymore help will be appreciated.
But it focuses on NA and the 12:1 JWT pistons would not be a suitable fit for boost on pump gas based on my understanding.
Personally, if I were pursuing boost, I would lean on the manufacture/install shop/tuner of the supercharger or turbo for compression ratio recommendations.
Sorry I didn't get back sooner, I haven't had time to comeback to this thread till now.
To answer your questions I'll be keeping a stock ECU with ECUcutek as I haven't found a standalone ECU for the G37 anywhere I've tired looking. My power goals I'd say are fairly high (roughly 600hp to the wheels). I do intend on sleeving my block with Daton sleeves aswell as using the Wiseco/Eagle pistons and rods
I wasnt too sure on what a "good" compression ratio for boost would be and I am still fairly new to anything in depth like that, I figure the normal 10:1 would be ideal for boost but I really am unsure.
The only reason I thought I may need to oversize the cylinder walls wasn't from a want to do so but rather it may have to happen during a cleanup if the engine has alot of debris or carbon build up inside the block, Im sure alot of the VQs by now (atleast any I can buy used) have really seen better says and have seen many many miles. My plan is to buy a X model longblock with the transmission and tear it all apart by hand to learn the ins and outs while also saving money instead of buying a remanufactured VQ from somewhere.
Hope that answers some of your questions and give you a better idea of my plans, anymore help will be appreciated.
I'll definitely have to give that a deeper look for some info. As of right now I'm in talks with AAM to make a TT kit for the X model Gs since we don't really have anything besides SC to have fun with and i prefer turbo whistle to a belt whine..
From what I do remember reading on AAM's website is they recommend a lower compression ratio and they also use Wiseco pistons and rods in their create engine options, but I still have no idea what cylinder bore they are using, it could be the factory 95.5mm or it could be something like 96.5mm, I'm really not sure. I really wanna go in depth and do a full engine rebuild myself to learn the ins and outs of the VQ37 without blowing it up once I put it back in.
I figure having a slightly bigger cylinder bore may provide a little bit of extra power but all I wanna do is have the walls cleaned up since the TT kit will already provide more than enough power. I guess ill have to wait until I hear back from AAM on what they recommend.
I'll definitely have to give that a deeper look for some info. As of right now I'm in talks with AAM to make a TT kit for the X model Gs since we don't really have anything besides SC to have fun with and i prefer turbo whistle to a belt whine..
From what I do remember reading on AAM's website is they recommend a lower compression ratio and they also use Wiseco pistons and rods in their create engine options, but I still have no idea what cylinder bore they are using, it could be the factory 95.5mm or it could be something like 96.5mm, I'm really not sure. I really wanna go in depth and do a full engine rebuild myself to learn the ins and outs of the VQ37 without blowing it up once I put it back in.
I figure having a slightly bigger cylinder bore may provide a little bit of extra power but all I wanna do is have the walls cleaned up since the TT kit will already provide more than enough power. I guess ill have to wait until I hear back from AAM on what they recommend.
Stop overthinkig this thing
you won't know if you need to "clean up the bore" until you get it apart.
And it sounds like you don't even have a motor to take apart yet.
If you plann on sleevinsleevingit don't matter if the bores are trashed or not, 'cause you'll be back to standard size of whatever sleeves get installed.
Sp no point ordering pistons till the machine shop is at least done inspecting/ measuring.
Talk to your machine shop and/or tuner before proceedproceeding.
Unless you are getting your hands dirty, state your power goals and your budget and let them build your motor.
Next big questions you should be asking about are all the supporting mods you'll need to keep "the beast" alive.
are you drag racing, tracking, or what?
Start with fueling, exhaust, then driveline, suspension, brakes, shift kit, differential(s), final drive, wheels/tires, etc
With VVEL you probably won't be doing cams. But a "port and polish" would still be worthwhile. Intake mods, injectors,, rails, fuel pumps, throttle bodies, methanol, nitrous, flex fuel, fuel pickups/mats, etc
Heat management is important and will differ on how you use your car.
Oil coolers, trans coolers, dif coolers, vented hood, fenders, aux fans
Many variables, and many tweaks. Some more necessary than others.
That's what makes this so much fun, and such a headache, and such a money pit lol
Stop overthinkig this thing
you won't know if you need to "clean up the bore" until you get it apart.
And it sounds like you don't even have a motor to take apart yet.
If you plann on sleevinsleevingit don't matter if the bores are trashed or not, 'cause you'll be back to standard size of whatever sleeves get installed.
Sp no point ordering pistons till the machine shop is at least done inspecting/ measuring.
Talk to your machine shop and/or tuner before proceedproceeding.
Unless you are getting your hands dirty, state your power goals and your budget and let them build your motor.
Next big questions you should be asking about are all the supporting mods you'll need to keep "the beast" alive.
are you drag racing, tracking, or what?
Start with fueling, exhaust, then driveline, suspension, brakes, shift kit, differential(s), final drive, wheels/tires, etc
With VVEL you probably won't be doing cams. But a "port and polish" would still be worthwhile. Intake mods, injectors,, rails, fuel pumps, throttle bodies, methanol, nitrous, flex fuel, fuel pickups/mats, etc
Heat management is important and will differ on how you use your car.
Oil coolers, trans coolers, dif coolers, vented hood, fenders, aux fans
Many variables, and many tweaks. Some more necessary than others.
That's what makes this so much fun, and such a headache, and such a money pit lol
So I've already got an AWD engine and transmission from a yard (with less than 100k miles on it aswell) which I'm currently disassembling bit by bit and learning what I can about this engine. As of right now I'm not far off from pulling the heads off to take a look at the cylinder walls and see what needs to be done.
When it comes to supporting mods I've already got a list of parts that will keep it reliable with my power goals, that goal being around 600whp. I do plan on taking it to the track and getting some lap times in here and there in my free time but it wont be a dedicated track car.
My parts list contains..
CJM euel eystem
AAM 3" exhaust
3.5" Aluminum driveshaft from Z1
Z1 adjustable suspension
Stuck between Toyo and Michelin tires
Differential is no worry because I'm AWD and we didn't get an LSD
GT-R injectors
Radium fuel rails
Walbro pump
Z1 fuel starvation kit paired with their oil pan
Simplisticgarage TBs
Z1 oil cooler
Stillen trans coolers
Fly1 ground attack vented hood
WB fenders with gills for air flow.
I have much much more I could list. I've done excessive research on parts for reliability and power so I can get the best of both worlds. I also agree that it is what makes it so much fun and so expensive.
The only reason I overthink is because I want this to be near perfect, I want it to be unique and stand out from all the takeover bums and unfortunately molested Gs that plague the community and maybe get rid of the stereotype.. that probably sounds super cringe I know but I'm seeking perfection with this build and I'd hate to see all the money put into it go to waste by making 1 simple mistake during an engine rebuild.
Research is a good thing
just saying you don't want to put the cart before the horse and order pistons without inspecting and measuring the bore or going sleeves.
And really, lots of guys hitting 600 on stock blocks out there.
Make sure you don't disturb the VVT actuator solenoid adjustment when pulling the heads.
Not sure the GTR injectors will deliver enough fuel, especially with flex fuel.
You'll need 1000cc? 1300? Ask your tuner.
And you'll definitely want better than an open diff in the rear! Helical is the way to go for a mostly street car.
Wavetrack. Quaiff, or Z1s newer knockoff are the the only ones on the market that im aware of.
Keep in mind, you cant change final drive gears without also swaping matching the ratio in the front diff.
Research is a good thing
just saying you don't want to put the cart before the horse and order pistons without inspecting and measuring the bore or going sleeves.
And really, lots of guys hitting 600 on stock blocks out there.
Make sure you don't disturb the VVT actuator solenoid adjustment when pulling the heads.
Not sure the GTR injectors will deliver enough fuel, especially with flex fuel.
You'll need 1000cc? 1300? Ask your tuner.
And you'll definitely want better than an open diff in the rear! Helical is the way to go for a mostly street car.
Wavetrack. Quaiff, or Z1s newer knockoff are the the only ones on the market that im aware of.
Keep in mind, you cant change final drive gears without also swaping matching the ratio in the front diff.
Oh yeah no need to worry, I plan on inspecting everything before I even think of purchasing stuff lol. I've just read alot stating that forged pistons are a must on boosted applications and all I really need to figure out was sizing.
I will also do my best not to mess with the VVT, I'd hope that simply pulling the heads straight off following the studs will work. Regarding the injectors alot of people have said the GT-R injectors are a good money saver option but I have looked into other options with around 1100cc to 1300cc, I do feel 1300 will be a little excessive but who knows, time will tell.
When it comes to a diff in the rear I've also read there isn't really a way to get one installed and there wouldn't be a reason to install one with having the Attesa system working to prevent and slippage on a track. Though I have always thought the GT-R has an LSD so why doesn't the G37x(S)? And my usual conclusion was because it's the halo car of Nissan. I'll definitely look into those options when time comes around to upgrade the rear end, I've already gotta replace the rear subframe stay/Brace so might aswell take a look around and see what else could use an upgrade right?
I will also be sure to let my tuner know about the final drive situation, I plan on reaching out to Moncef from Admin or someone from RSEnthalpy since they seem to be the leaders when it comes to tuning these engines.
I happened to see this thread and figured I’d offer some parts if interested. I had a dealer install a stillen sc in my 2014 Q60S (before the Q60 body changed in 2015). Car has about 39K on engine and AWD trans. I blew the motor messing with octane boost and other crap. The car is completely intact. The plugs were completely sucked into the heads on driver side.
You may be interested in:
stillen exhaust
stillen oil cooler
stillen trans cooler
entire stillen sc
??? the car is a complete roller rn and I haven’t decided if I’ll part it out or rebuild it.
PM me if you want to discuss it. It even has new Michelin pilot sport 4S tires but the car has been sitting.
chris
Originally Posted by DanaT
So I've already got an AWD engine and transmission from a yard (with less than 100k miles on it aswell) which I'm currently disassembling bit by bit and learning what I can about this engine. As of right now I'm not far off from pulling the heads off to take a look at the cylinder walls and see what needs to be done.
When it comes to supporting mods I've already got a list of parts that will keep it reliable with my power goals, that goal being around 600whp. I do plan on taking it to the track and getting some lap times in here and there in my free time but it wont be a dedicated track car.
My parts list contains..
CJM euel eystem
AAM 3" exhaust
3.5" Aluminum driveshaft from Z1
Z1 adjustable suspension
Stuck between Toyo and Michelin tires
Differential is no worry because I'm AWD and we didn't get an LSD
GT-R injectors
Radium fuel rails
Walbro pump
Z1 fuel starvation kit paired with their oil pan
Simplisticgarage TBs
Z1 oil cooler
Stillen trans coolers
Fly1 ground attack vented hood
WB fenders with gills for air flow.
I have much much more I could list. I've done excessive research on parts for reliability and power so I can get the best of both worlds. I also agree that it is what makes it so much fun and so expensive.
The only reason I overthink is because I want this to be near perfect, I want it to be unique and stand out from all the takeover bums and unfortunately molested Gs that plague the community and maybe get rid of the stereotype.. that probably sounds super cringe I know but I'm seeking perfection with this build and I'd hate to see all the money put into it go to waste by making 1 simple mistake during an engine rebuild.
