VQ35 vs VQ37 Strength of Internals Comparison
06-14-2010, 06:54 PM
#16
Registered User
SR20 compression and VQ37 compression are totally different.
That being said, it's all in the tune...
Keep in mind, cooling is a huge issue with the VQ37VHR. If budget were not a concern, I'd go as far as putting a VQ35HR top end on a VQ37 and run a full standalone capable of individual cylinder management
That being said, it's all in the tune...
Keep in mind, cooling is a huge issue with the VQ37VHR. If budget were not a concern, I'd go as far as putting a VQ35HR top end on a VQ37 and run a full standalone capable of individual cylinder management
06-14-2010, 06:55 PM
#17
Registered User
Full builds are absolutely NOT NECESSARY.
If someone wanted to go above 8 psi I would start recommending upgraded internals.
Realistically, I don't see any reason why these cars can't go well over 100K miles with superchargers or turbo kits...It all depends on boost, tuning, and regular maintenance.
If someone wanted to go over 8 psi and wanted to start pushing more power, I would start recommending forged, redesigned pistons, maybe thicker rods depending on expected power levels...It really just depends on what the customer wants.
If someone wanted to go above 8 psi I would start recommending upgraded internals.
Realistically, I don't see any reason why these cars can't go well over 100K miles with superchargers or turbo kits...It all depends on boost, tuning, and regular maintenance.
If someone wanted to go over 8 psi and wanted to start pushing more power, I would start recommending forged, redesigned pistons, maybe thicker rods depending on expected power levels...It really just depends on what the customer wants.
06-14-2010, 07:04 PM
#18
Everything is looking excellent for the aftermarket engine warranty.. more details soon..
We running you out of excuses yet?
EDIT: Forgot you're out of the country.. Wouldn't apply that far away.. but for others
We running you out of excuses yet?
EDIT: Forgot you're out of the country.. Wouldn't apply that far away.. but for others
06-14-2010, 07:10 PM
#21
SR20 compression and VQ37 compression are totally different.
That being said, it's all in the tune...
Keep in mind, cooling is a huge issue with the VQ37VHR. If budget were not a concern, I'd go as far as putting a VQ35HR top end on a VQ37 and run a full standalone capable of individual cylinder management
That being said, it's all in the tune...
Keep in mind, cooling is a huge issue with the VQ37VHR. If budget were not a concern, I'd go as far as putting a VQ35HR top end on a VQ37 and run a full standalone capable of individual cylinder management
! Haha. But yeah, I do realize the compression is much higher on the VQ. I just figured that the lower amount of boost and significantly larger displacement and two more cylinders would essentially be a "wash" AT 8psi. Anything over that is a crap shoot, IMO.Keep in mind that little T on the end of SR20DET...That little T means that NISSAN knew that the engine was going to be turboed from the very beginning. Just look at the compression ratio. The stock compression ratio of the SR20DET is only 8.5:1. The stock compression ratio on the VQ37HR is 11:1. That is a HUGE difference which means you can't run as much boost. 20-21 psi is probably pretty normal and safe on the SR20DET. Running 20-21 psi on the VQ37 would result in a nice little window forming in the side of your block. Great to see the inside of your combustion chamber or crank case...bad for engine performance though...
Obviously I know that you know that 20 psi is unrealistic on a stock 370Z block but some people don't and I try to write everything to give everyone answers, not just the person I'm quoting.
In my opinion, just like you said, 8 psi is a good target for a safe power level that will go for a long time with a good tune and regular maintanence
Obviously I know that you know that 20 psi is unrealistic on a stock 370Z block but some people don't and I try to write everything to give everyone answers, not just the person I'm quoting.
In my opinion, just like you said, 8 psi is a good target for a safe power level that will go for a long time with a good tune and regular maintanence
. Yes, I do realize there is a HUGE difference in the compression ratio's of the SR and VQ37 but as I stated above, I figured that things would essentially "even" out with the VQ's much larger displacement as well as extra cylinders to space things out. That is IF you only run 8psi tho. With the compression ratio so high and this motor not being made for FI, I wouldn't personally run anymore than 8 to 10psi to try and keep things as reliable as possible. Thanks for you input Kyle and Mike.
06-14-2010, 07:29 PM
#22
Administrator
How hard do you think it would be to bolt an HR head to the VHR? I'm really loving the sound of that at the moment
06-14-2010, 07:38 PM
#24
Yup, they were the LS/Vtec. Unfortunately, most of them didn't last too long. For some reason, they just were not as reliable as most Honda creations.
06-14-2010, 07:49 PM
#26
Registered User
the VVEL is not the reason for the high whp figures obtained with boost. It does help, but the HR does just as good even though it has less displacement and less CR (10.6:1 vs. 11:1). Just take a look at GTM's Stage 2 TT 508rwhp G35 sedan build on youtube.
The reason I would go with an HR head too (or for me, VHR bottom end) is the possibility of running aftermarket cams, adjusting cam timing and simply much easier to build, maintain, etc. VVEL is cool if you want to stay stock or just bolt ons + tune, but it's far too complicated IMO if you wanna go all out.
The reason I would go with an HR head too (or for me, VHR bottom end) is the possibility of running aftermarket cams, adjusting cam timing and simply much easier to build, maintain, etc. VVEL is cool if you want to stay stock or just bolt ons + tune, but it's far too complicated IMO if you wanna go all out.
06-14-2010, 08:00 PM
#27
Administrator
+1, the VVEL to us gearheads imposes more of a restriction
Its beauty is that you can have different cam lift at every rpm, meaning you can achieve max torque at that rpm at each and every rpm, maximizing your volumetric efficiency at all rpms.
With traditional after market cams, you sacrifice low-end efficiency for some high end, when you have boost however, one wouldn't mind sacrificing a few horses for tens in the high end
Its beauty is that you can have different cam lift at every rpm, meaning you can achieve max torque at that rpm at each and every rpm, maximizing your volumetric efficiency at all rpms.
With traditional after market cams, you sacrifice low-end efficiency for some high end, when you have boost however, one wouldn't mind sacrificing a few horses for tens in the high end
06-14-2010, 08:52 PM
#28
I thought one of the weaknesses with the original VQ35 motors was their rod bolts were the first to let go with big power/torque numbers. Does anyone know if the OE bolts were improved over the years with the HR/VHR motors? I guess if you were going to build a motor you would replace the bolts with ARP, but I was curious about the stockers.
06-14-2010, 11:37 PM
#29
Registered User
If you mean leasers shouldn't be modding their cars, well, I agree -- but to each his own I guess. One benefit might be a surplus of slightly-used aftermarket parts available on ebay and craigslist for the rest of us when all those leases expire!
06-15-2010, 12:42 AM
#30
The way I read it as "note" to mean "loan," as in promissory note, not lease. I don't see any problems with modding a car you own but are still making payments on. I do it to my house all the time!
If you mean leasers shouldn't be modding their cars, well, I agree -- but to each his own I guess. One benefit might be a surplus of slightly-used aftermarket parts available on ebay and craigslist for the rest of us when all those leases expire!
If you mean leasers shouldn't be modding their cars, well, I agree -- but to each his own I guess. One benefit might be a surplus of slightly-used aftermarket parts available on ebay and craigslist for the rest of us when all those leases expire!
I love when people say "I purchase my cars because I like to own it" and continue to make payments on the car while trading it in every few years.
Granted, a home is typically going to hold its value, while a car is not. When you mod a car, its value drops even further.
I bet most people here don't even have insurance coverage on their mods
Only other people I know of for sure is Gamedog and Dahashi.Now, this isn't typical, but if a car were to be repo'd with illegal mods, well, they're not gonna be happy, especially since if the car was repo'd its cuz payments were not made, and the mods had to have come from somewhere...
On the flip side, if a house was foreclosed with (well done) mods, they'd be a little less pissed.