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Got tuned the work day after (they were closed Sunday for cleanup). I had Monday off, so it worked out.
Due to the nature of in-person tuning (IE, if you want a baseline and then to do all your mods and THEN tune, you're going to pay for their time to wait around on you) the mods were all done when I got there. First pull with no tune (IE, mods and stock maps) was 299/255. Looking online 275-280 for a stock motor seems to be average. So the mods (primarily exhaust) gain 20ish HP. Also, keep in mind that the G35 intake manifold lost me power on the top end - that was an understood compromise.
Basically, yes. The tune gained me 15HP over just the mods themselves. But... if you look at the numbers below the graph, you'll see the last 6 runs he was tweaking for torque, and I was actually losing HP. After discussing why the manifold from the older motor and what I was looking for, he got it to an HP peak and then started tuning for higher torque which brought the HP down some.
IIRC, the dyno whiteboard from the Z Nationals list - the guy with 303 HP had very similar mods to mine excepting the manifold. And bear in mind that this is not ported or smoothed in any way. I'm pretty happy overall. The powerband is more linear and I have more available in the street driving ranges - but I don't feel any loss up top. Running it out to redline on an interstate onramp pulled smoothly to speeds that are theoretically illegal everywhere.
Still plan to clean up the other G35 manifold I have, adapt the G37 fuel rail to the G35 upper and lower, and install that with a better thought out vac line routing. But what's there now works, and does what I hoped it would do.
That seems like a very practical and realistic attitude.
Enjoy the mid-range gains. And forget about winding the gears to redline... driving on the street like that is dumb 98% of the time anyway. Which leaves 2% available to be an occasional ahole, LOL.
Thinking back to my remote tune, the thing I appreciate the most is how much more smooth my car is now, and how much better gear shifts are. I'd take that any day over peak HP numbers.
Were it a track toy, things would be different. But for a street car I feel like this is a sweet spot. And it’s very civilized- I could hand the keys to any unsuspecting friend (that can drive stick) and they’d be perfectly safe. No peaky powerband or difficult clutch.
So having lived for 2 weeks with the tune, I can say it just makes the car better, without being massively different. I mean, they're getting close to 100HP/liter stock, that was the golden ratio back when the S2000 came out... there isn't much room for improvement except through radical engineering or FI or both.
I've been focusing on other things since getting back from Georgia so all I've been doing with the car is daily driving it.
I did get the entire interior back in minus the seat rail end caps. Still need to wrap the door trim on driver and both rear doors. The carbon flake wrap in the center stack is a bit much... contemplating some changes there. Center stack suede shift boot, new heavy Razo ball, and @iCrap 3D printed cupholder are great. Leather from a Journey on the passenger seat back is taking a better fit now that folks have sat in it, and it not scratching the hell out of the inboard arm with broken vinyl is nice.
Once I get some car time again I need to finish the VQ37 fuel rail on VQ35 lower intake manifold project and swap an unmodified VQ35 upper mani in, and redo the vac lines to make more sense. But what I have now... works.
And naturally, since I talked to the SPL guys at the show and had them look at my car, now the whiteline sway bar ends are behaving.
So nothing big in process now, just little annoyances that need to be fixed to make the car effortless.
I think the Red Nismo 370Z springs are too much for the car. Looking at standard 370Z options.
Still have the damn sway bar end link loosening - 5 to 15 minutes and it is loose and clunking. Going to disconnect that end entirely tomorrow and see if that solves all the clunks.
Gauge pod a-pillar. Clock OBD2 gauge. Rear wing. Rear badges. Little stuff now.
One bolt (#5 counting from the front, not including the nut) just wouldn't go - too close to the wall. That one will need another longer bolt and a larger washer... but for now, left it out.
Other things not mentioned in the thread mentioned above. The Throttle Body crossover/coolant pipe assembly at the back of the manifold won't fit without judicious bending. I think I have a VQ35 one, will give that a try to clean things up. The PCV reroute to the lower rear manifold nipple is to put it mildly, a hack. So will have to re-engineer that one so it isn't sucking too much vacuum / oil. Possibly including catch cans.
Monday I had it tuned with John at Z1. Had a conversation about why the hell I would put the older manifold on there, but the proof is in the pudding - nice, smooth torque curve down low.
Last pull was the olive green one - 314 HP at 6800 RPM, 273 ft/lbs at 4920 RPM. No issues with the manifold at all.
Power affecting mods: FI resonated HFC, FI Catback, VQ35 upper intake manifold, Z1 after-MAF tubes, 2.75" MAF housings with honeycomb air straighteners, 2.5" intake piping to RC Engineering filters in front of the radiator panel. That's it, and that's about as far as I need to go.
From looking on the web, it seems like the driveline loss is between 13 and 16% so that means 355-364 HP and 308-316 ft.lbs. Not too far off the Z1 400 HP package that also includes headers and test pipes.
I have done the same mod but have not been to the dyno yet. And had to leave out that same bolt!! Stock otherwise. I will do LTH & Catback & 3.69 gear swap later. A tune will be the last thing I do. Ran this ET with just VQ35 upper. Drop in filters and shorter (25") rear tires.
So nothing big in process now, just little annoyances that need to be fixed to make the car effortless.
I think the Red Nismo 370Z springs are too much for the car. Looking at standard 370Z options.
Still have the damn sway bar end link loosening - 5 to 15 minutes and it is loose and clunking. Going to disconnect that end entirely tomorrow and see if that solves all the clunks.
Gauge pod a-pillar. Clock OBD2 gauge. Rear wing. Rear badges. Little stuff now.
Not really - there are (or were -haven't looked at it in ages) several 1/8 tracks around here if I want professional numbers, and if not the OBD Fusion app will do the same.
I started there too - Z1 after-MAF tubes on stock intake.
I have a longer bolt for the rear hole, just haven't had any under-hood time since Z nationals. Not seeing any signs of air/vacuum leakage so not too worried.
The goal is to modify a G35 lower intake manifold to accept the G37 fuel rail (or vice versa, likely some of each) and use an unmolested G35 upper intake manifold with the proper bolts etc. I have both sitting in my garage.
obtained a ZSpeed undertray from their BF sale. Haven't had time to put it on - or change the oil - yet. I'm only 1k over my 5k interval... been stupidly busy at work and home past few months.
I did change the hood struts (which were getting weak) with some ebay ones that are red (to match the other red underhood stuff).
10-14-2021, 04:49 PM
Stock otherwise. I will do LTH & Catback & 3.69 gear swap later. A tune will be the last thing I do. Ran this ET with just VQ35 upper. Drop in filters and shorter (25") rear tires.
