Nissan 370Z Forum

Nissan 370Z Forum (http://www.the370z.com/)
-   Engine & Drivetrain (http://www.the370z.com/engine-drivetrain/)
-   -   Building heads before boost or bottom end (http://www.the370z.com/engine-drivetrain/125847-building-heads-before-boost-bottom-end.html)

SS_Firehawk 02-14-2018 03:34 PM

Building heads before boost or bottom end
 
So seeing that I have a spare set of heads and a collection of parts, I've been slow rolling on moving towards building them.

So far, my parts list includes:
JWT C2 cams
JWT cam sprockets
ATI Damper
RJ Manufacturing Oil Pump Gears
Super Tech 1mm oversized intake and exhaust valves

On the spare set of heads currently:
Supertech dual valve springs (unsure if on just exhaust side or intake and exhaust)
Custom VR38 Tomei Cam (I think 282 duration and 11mm lift, could be wrong, but it's aggressive). A million variables here...

The questions and concerns I have are:

I can spend $1000 and get a damn good hand port done.

Go broke and have the heads CNC ported.

The 1mm oversized valves might slow down air velocity and kill my low end.

Are the larger valves lighter or heavier than stock?

Getting the heads CNC'd will kill my wallet for minimal gain or loss of low end.

I build it with minimal work on the valve seals to fit the valves and assemble it with the JWT parts and have FOMO for not doing the port work.

Say F@ck the world, CNC it, maybe order stiffer intake valve springs, add the JWT stuff, the super tech 1mm valves, take as much time as I need to do it and throw it on my NA Z; Boost and build the bottom later.

I literally have everything. It's just paying the labor rates now. So I'm scratching and clawing step by step to get this far. Even if in the near term I don't make any serious gains, when boost is introduced, it will show a huge benefit in how much boost it takes to reach X amount of HP. It will reduce the delay and lag as the flow will be higher (Takes less time to reach 12PSI vs 15PSI). And even though most guys build their heads for crazy power numbers, I really just want to optimize my power delivery for my goals. I want the car and turbos to breath at 8k rpm, I don't want to max the turbos to reach 650-700whp, with a power curve that looks like a door stop and TQ that's as flat as Kansas. I don't need or desire gobs of TQ down low; but very consistent and manageable. This is absolutely not the most cost effective way to make this kind of power. I don't need built heads or cams to get there, it's just where I'm going with it.

Anyways. I'm just looking for thoughts and input on what I'm planning. Will i see a benefit before drinking boost juice or not? And for any of the old guys on here, you all know I tend to veer off and do my own thing and experiment. So I don't need people telling me it's a waste of money. It's my money and I'll do what I want.

Rusty 02-14-2018 11:24 PM

If you got the parts. I say go for it. Do it once as to doing it twice.

BGTV8 02-14-2018 11:33 PM

I agree

Quicksilvers 02-15-2018 12:19 AM

If you have all the parts I would install everything and have your cylinder heads CNC ported there will be benefits from it. I have seen the JWT C2 camshafts make really good mid range and top end power. I wouldn’t really worry about losing a lot of low end torque since the JWT C2 camshafts will really shine in other areas of the power band. You should do this now that way you will not have to do it later on.

Elmo370z 02-15-2018 01:28 AM

Do it after I go boost

SS_Firehawk 02-15-2018 06:28 AM

Thanks for the responses. Glad I'm not alone in my logic. Just making sure I was thinking the right way about it. Those valves I got on a killer deal, so I just snatched them up. I picked them up for $500.

On another note. The valve springs on the intake side are the same as the exhaust (most likely not the spring rate). I'm curious if anyone knows the specs on them. If there's a way to eliminate the valve float for another 500rpm, I believe there would be a benefit having that extra rpm with the right cam profile and maximizing the ported heads.

Jayhovah 02-15-2018 09:10 AM

You and Elmo are going to give me shrinkage.

jchammond 02-15-2018 10:07 AM

Go for it...Then make a post on how to obtain “Maximum-Traction”
:)

DYNAZOR 02-15-2018 10:30 AM

Go broke and have the heads CNC ported.[/QUOTE]

I don't think going broke is ever a good idea.

SS_Firehawk 02-15-2018 11:04 AM

Figure of speech.

Spooler 02-15-2018 11:04 AM

If you are going to pull it that far down I would go ahead and do pistons and rods. The motor will need to come out anyways.

SS_Firehawk 02-15-2018 12:45 PM

I'm pretty sure you can swap heads without dropping the motor. Even then, that's adding significant cost and downtime unless I purchase a separate block, which only increases cost. If the scope continues to creep, it will never be completed. If I at least get the heads done, there will be data on what that looks like on with just stock bottom end, so no more smoke and mirrors or whatif's. I can enjoy it while I work towards the next goal, and maybe it will motivate companies to look further into the VVEL issue if more guys put their mind, money, and balls into pushing the real unknowns of this motor.

Hotrodz 02-15-2018 04:27 PM

Quote:

Originally Posted by SS_Firehawk (Post 3730826)
I'm pretty sure you can swap heads without dropping the motor. Even then, that's adding significant cost and downtime unless I purchase a separate block, which only increases cost. If the scope continues to creep, it will never be completed. If I at least get the heads done, there will be data on what that looks like on with just stock bottom end, so no more smoke and mirrors or whatif's. I can enjoy it while I work towards the next goal, and maybe it will motivate companies to look further into the VVEL issue if more guys put their mind, money, and balls into pushing the real unknowns of this motor.

Creep happens and you will never be done!

Sent from my SM-N910P using Tapatalk


All times are GMT -5. The time now is 10:46 PM.

Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 PL2