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I normally go when there's a 40% off holiday weekend. The 4th of July was insane - there were at least 300 people at the LKQ in Charleston. They put up a hot dog cart in the parking lot
I have the app and I get notifications when a new car comes in. That's how I know that they only last around 4-5 days. They strip *any* car that comes in that soon - its almost impossible to find common parts on cars past that point.
I did score the G35 lower, upper, rail, throttle bodies, and all ancillary hardware for a reasonable price. I need to go grab an engine when they have the sale and I have the space to store one.
I've got several of each sitting in the garage and a 37 lower and 35 lower. From both what I've been told here and comparing runner length/diameter of the lower intakes, they are the same except for bolt locations for the upper (and fuel rail).
I'm sure there's gains to be had from porting/polishing any intake tract component, but IMHO you start looking at diminishing returns. I'm willing to bet that you'd get more gains from putting a catch can in the PCV system so the insides of the runners don't get oil/gunk caked on them (reducing the diameter, even if just a bit).
My goal is to put 80 grit, then 120, 240, 400 grits on a flex-shaft (think abrasive bottle brush) and run it through the bores to smooth them out some, port-match the throttle body flanges, but that's it.
The difference between 35 and 37 uppers is in the intake tuning - the designed torque peak / resonant frequency of the runners is lower, so any similarly sized engine they're placed on will experience the torque shift. Keep in mind - you are LOSING top end power with the 35 manifold. You are gaining power under the middle of the curve - which is where most of us drive, so you'll likely never notice the top end loss.
I've got several of each sitting in the garage and a 37 lower and 35 lower. From both what I've been told here and comparing runner length/diameter of the lower intakes, they are the same except for bolt locations for the upper (and fuel rail).
I'm sure there's gains to be had from porting/polishing any intake tract component, but IMHO you start looking at diminishing returns. I'm willing to bet that you'd get more gains from putting a catch can in the PCV system so the insides of the runners don't get oil/gunk caked on them (reducing the diameter, even if just a bit).
My goal is to put 80 grit, then 120, 240, 400 grits on a flex-shaft (think abrasive bottle brush) and run it through the bores to smooth them out some, port-match the throttle body flanges, but that's it.
The difference between 35 and 37 uppers is in the intake tuning - the designed torque peak / resonant frequency of the runners is lower, so any similarly sized engine they're placed on will experience the torque shift. Keep in mind - you are LOSING top end power with the 35 manifold. You are gaining power under the middle of the curve - which is where most of us drive, so you'll likely never notice the top end loss.
I went ahead a while back and I believe I posted this somewhere else about the reason why the swapping both upper and lower is a bit more than what it shows. This issue is the fuel rail. See below
ID of the top hat of the HR rail VHR lower and HR rail VHR lower and HR rail HR lower and HR rail VHR rail on HR lower. As you can see there is no Boss hole to bolt the bank 1 side of the rail in the back. A bracket could be fabbed however I beleieve adapting the HR rail is the way to go Notice the location of the fuel dampners? It appears as the HR fuel dampeners will interfere with the VVEL hump of the valve cover and possibly might not work. However it is possible to maybe cut off that L bracket on the left rail of the HR rail and weld it to the VHR rail. The other holes need to be elongated to bolt perfectly VHR left HR right As you cans see the inside diameter of the fuel hats is smaller on the HR, This could be drilled maybe.
This is essentially what it would take for you to properly swap upper and lower. I believe this is an easier feat to accomplish than free form cutting plastic. The best part is that it can be mocked outside of the car to the point that once it's done it's just remove and replace
Im confident any fabricator can fab these brackets and get it done.
Interesting point about the pulsation dampers interfering. I thought the VQ35VHR was basically identical except for displacement? IE, VVEL etc the same.
Interesting point about the pulsation dampers interfering. I thought the VQ35VHR was basically identical except for displacement? IE, VVEL etc the same.
The dampeners was something I did not thing about when considering this swap and The hump is pretty significant. On top of that I learned at the JY that the ID of the feed holes of each injector is significantly smaller than the HR ones. So going the HR rail route is not an efficient one.
Modifying your VHR rail to fit the HR manifold seem like the way to go.
I still dont think this manifold is worth effort, at least not without some proper porting, The VHR does spend quite some time in the top when going through the gears hard meaning you will feel the decrease in the highway. In the city it should be pretty good.
Are the feed holes just smaller on the rail, or on the injectors too? (IE, what's the top look like for a 37VHR vs 35HR injector)
Some porting, yes. But I wonder - the Z1 400HP package includes this when it otherwise wouldn't need to, and their ported intake is mostly just smoothed inner surfaces.
Moving mounting tabs on the newer fuel rail should be easy enough. I need to grab a 37VHR fuel rail next time I'm in the junkyard.
Edited to add: I doubt any of this dramatically increases power output without a tune.
Are the feed holes just smaller on the rail, or on the injectors too? (IE, what's the top look like for a 37VHR vs 35HR injector)
Some porting, yes. But I wonder - the Z1 400HP package includes this when it otherwise wouldn't need to, and their ported intake is mostly just smoothed inner surfaces.
Moving mounting tabs on the newer fuel rail should be easy enough. I need to grab a 37VHR fuel rail next time I'm in the junkyard.
Edited to add: I doubt any of this dramatically increases power output without a tune.
The injector from an outside perspective is the same. VHR is orange/ HR is green. The only time the rail would come into play is under high power other than that it would be fine however in my book the VHR rail not only is bigger but more compact thant the bulky HR one.
What I mean about the porting is to maximize your chances at not dropping high rpm power, Moncef from admintuning believes the HR manifold is a waste however this is in part due to the amount of work and the fact that most of the cars he tunes are for high rpm high horsepower. Even the 350z guys swap to VHR manifolds and consider them upgrades to to shifting that powerband making them top end killers.
In all reality it will take experimentation and tuning to prove to see if this manifold's chocking at high RPM is significant and if it counters the gain made from the better midrange.
It honestly shouldn't be *much* of anything - the torque peak shifted from 4800 to 5600 if I recall correctly, that isn't huge.
It also depends on what you're driving and where - I can totally see putting a 37 manifold on a 350Z for a little more top-end on the track. Although I'd honestly just put the whole 3.7L in there, as cheap as they are in junkyards, maybe with 3.5 heads if that is a thing.
For a street only car - one that's not designed to race, not really - I think lowering the torque peak, like higher ratio rear gears, would improve driving experience.
It honestly shouldn't be *much* of anything - the torque peak shifted from 4800 to 5600 if I recall correctly, that isn't huge.
It also depends on what you're driving and where - I can totally see putting a 37 manifold on a 350Z for a little more top-end on the track. Although I'd honestly just put the whole 3.7L in there, as cheap as they are in junkyards, maybe with 3.5 heads if that is a thing.
For a street only car - one that's not designed to race, not really - I think lowering the torque peak, like higher ratio rear gears, would improve driving experience.
I'm Already mentally set on the 3.69 rear diff which would be interesting to see paired up with this manifold.
I'm Already mentally set on the 3.69 rear diff which would be interesting to see paired up with this manifold.
That's the gear I am going with plus shorter tires. My effective gear moves from 3.35 stock to 3.85 with the tires & gear swap. That will be a big difference. And should help with the upper intake on the topend!!
07-24-2019, 04:35 PM
