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I messed up by buying what I thought was a vq35hr. It was in a 2007 G35. Turns out the G35 coupe continued to get the DE engine for one more year.
Ok, so I got a good engine but not the better engine. I'm gonna tear it down and freshen it up. I'd like to get the longer rods the hr has which may require the hr pistons or a stroker piston. either way, is this as simple as I make it sound. iI guess that means an hr crank or a aftermarket rod that fits the de crank. Secondly, will the hr double throttle body intake manifold fit the de engine?. If so which is the best hr aftermarket intake to put on the de engine. Next I plan on getting bigger cams and getting different cam gears. I don't know anything about what I should consider as this is new to me. I plan on cleaning up the intake and exhaust ports. Should I up the valve size by a little or is that not possible without spending crazy money. if so, I'd like to lighten up the valvetrain and reduce friction. What are my best options to do this.

Please share with me how I can get the most reliable power from the de engine I picked up. Also, how can I tell if this is Rev up engine.

FYI, this swap is going in a 74 Triumph TR6 track car. I would love to achieve 400-450 NA rwhp.
Thanks
Roger
 

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You can forget getting 400-450 NA rwhp from either the HR or DE. Full race development wasn't able to get those figures (with comparable torque) from the VQ35DE. Nissan did a good job with R&D and built a reliable NA engine, but there's not a 25-30% output window to explore. I'd suggest doing a mild rebuild with new bearings and rings, and a topend rebuild. If you're using standalone engine management, spend some money on dyno testing to extract as much as you can (probably only 25-35 HP) without wasting money.
 

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I messed up by buying what I thought was a vq35hr. It was in a 2007 G35. Turns out the G35 coupe continued to get the DE engine for one more year.
Ok, so I got a good engine but not the better engine. I'm gonna tear it down and freshen it up. I'd like to get the longer rods the hr has which may require the hr pistons or a stroker piston. either way, is this as simple as I make it sound. iI guess that means an hr crank or a aftermarket rod that fits the de crank. Secondly, will the hr double throttle body intake manifold fit the de engine?. If so which is the best hr aftermarket intake to put on the de engine. Next I plan on getting bigger cams and getting different cam gears. I don't know anything about what I should consider as this is new to me. I plan on cleaning up the intake and exhaust ports. Should I up the valve size by a little or is that not possible without spending crazy money. if so, I'd like to lighten up the valvetrain and reduce friction. What are my best options to do this.

Please share with me how I can get the most reliable power from the de engine I picked up. Also, how can I tell if this is Rev up engine.

FYI, this swap is going in a 74 Triumph TR6 track car. I would love to achieve 400-450 NA rwhp.
Thanks
Roger
You can forget getting 400-450 NA rwhp from either the HR or DE. Full race development wasn't able to get those figures (with comparable torque) from the VQ35DE. Nissan did a good job with R&D and built a reliable NA engine, but there's not a 25-30% output window to explore. I'd suggest doing a mild rebuild with new bearings and rings, and a topend rebuild. If you're using standalone engine management, spend some money on dyno testing to extract as much as you can (probably only 25-35 HP) without wasting money.

I find this site interesting.... lots of people come in with a question then never come back to the thread. Wonder why that is.....


In any event, no, you cannot get 400-450whp from a normally aspirated VQ, don't care what kind. And no, you cannot put the dual TB HR top end onto a DE. And RevUp has extra valve timing solenoids...you can tell by looking at the timing covers. You want to stroke the engine, plenty of options, go look at supporting vendors, any of them that offer engine upgrades have stroker kits.



Seriously, all this info is out there with a flick of the google.
 

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LOL, I'm still here. Lurking I suppose.

I did find a post that a team got 370 wheel hp from the VQ35de. But that was expensive with itb injection. I was thinking of using stroker pistons and getting a little longer rod length to improve side load geometry. That'll make it easier to turn a few more revs with out the concern of throwing a rod. And that is speculation based on my other builds. This engine is all new to me. I can handle the headwork which is only cleaning up and slightly opening the the intake runners and only cleaning the exhaust ports. I'll unshround the valves just slightly. Would really like to add back material in the combustion chamber to add more Quish. But I'd prefer to have a set of spare heads to do that as that would be pure experimental for me. More quish ups teh compression a bit but more importantly allows the combustion chamber to be slightly cooler. That will help control detonation. I assume these DE's have knock sensors. And as was mentioned, I'll run an aftermarket standalone management system because I think I'll get better safer control. I use a Tuner in my area and he dyno tunes then street tunes. Jim Wolfe has some big cams that produce good power, but they are for track only. I was hoping to drive teh car on the street from time to time.

If you have tried something that yielded good results please share it with me.

Since the HR dual tb intake doesn't fit the de, is there an intake available that is dual tb. If not, will the hr heads fit on the de block. Just curious
Thanks
Roger
 

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Absolutely no hope of getting a NA DE to 400whp
$15k race DE's get close to 400 hp at the flywheel - at over 8,000 rpm - a lot of money and engineering needed to make that viable & reliable

There are a lot of differences between the DE and HR - major parts are generally not interchangeable between them

To accommodate the longer rods (and reduce piston side wall pressure) the HR block was 7~8mm higher than the DE (rather than shorter pistons)
In the HR, the conrod bearing journal was 5mm wider and diameter increased by 2mm
Good luck getting those rods into a DE...

There is no weight to be saved in the DE valve train - it's cam direct onto buckets over the valves
The HR used buckets that reduced friction and they do fit the DE
$24 each = $576

There is very little room in the combustion chamber to add metal
The compression ratio is normally raised using pistons with material entering into the combustion chamber

It's bloody hard and expensive to get more power from NA engines
You will need to raise the compression ratio and use hot cams
Absolutely necessary to replace the DE plenum to get it breathing better - or at the very least heavily modify it
If you get anywhere near 400hp (flywheel) it will not be pleasant to use on the street

Your best bet is to rebuild for reliability and run a low boost turbo setup

There are bolt on super chargers that do raise the power a lot - but they need constant attention and are expensive
 
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