Custom manifold/plenum/TBs

FPenvy · 11-18-2014, 02:32 PM

Quote:

Originally Posted by gomer_110

The real reason this will probably the only one GTM will ever make is because almost nobody would be willing to give them that kind of money with all the horror stories others have had regarding their business practices.

While $1500 is more than many people would be willing to spend, there is most certainly a market for a high performance mani at that price point assuming it provides considerable gains. Given that ~340whp is about the max most NA people with full boltons have got, being able to get up to the 360-370whp range is worth the extra coin.

Honestly, I don't care what it looks like so long as the gains are great. Having a shiny piece under the hood is pointless for many unless the performance gains are there.

still there is the major problem. no one has pulled big or even good gains from any manifold. Z1 got a few HP here and there but nothing worth paying that kind of money for.

i'm right there with you. if theres a considerable gain then yea i got no problem handing over the money.

just need to make something that produces power. who cares if its eye candy or not.

BGTV8 · 11-18-2014, 02:52 PM

Or adapt the Jenvey ITB like Sasha Anis did with the ex-Fontana Racing 350Z when he upgraded to VQ37 internals and JWT Grand Am cam package

410+hp atw is close to 500@ the crank

BTW, look what I found in the back of my ute !!!

Rusty · 11-19-2014, 12:44 AM

Quote:

Originally Posted by BGTV8

Or adapt the Jenvey ITB like Sasha Anis did with the ex-Fontana Racing 350Z when he upgraded to VQ37 internals and JWT Grand Am cam package

410+hp atw is close to 500@ the crank

BTW, look what I found in the back of my ute !!!

I hate you!

vividracing · 11-19-2014, 06:59 PM

Just a thought, but i came across this, and wanted to give you a heads up.. You might wanna pick this up

GTR Intake collector and cover

ViCiouS · 11-19-2014, 07:46 PM

Quote:

Originally Posted by vividracing

Just a thought, but i came across this, and wanted to give you a heads up.. You might wanna pick this up

GTR Intake collector and cover

That's basically option 2 from the first post, you have to have a custom lower manifold, cut intake piping, and get custom fuel rails. Would be nice if it was plug n play, but that's the point of this thread

Eclipz · 11-19-2014, 11:33 PM

Avery370z got his manifold extrude-honed, got decent gains after tune. Lower intake

ViCiouS · 11-24-2014, 10:36 PM

^ that was gains from headers and manifold. Still no real knowledge on manifolds alone. :/

Well anyways I got my manifolds off yesterday, started doing some measurements and such on breaks from installing headers (a pain in the *** to do alone btw, passenger done, drivers side getting done sometime this week). Got to thinking about what options for manifolds can be made and what will be most efficient.

Equal length manifolds
Pros - easiest to design, equal air to all cylinders
Cons - more bends in piping, reducing efficiency

Shortest runners direct from TB
Note - a smaller plenum with short runners is also an option to help with harmonics of opening and closing valves
Pros - least bends, probably most efficient
Cons - very difficult to design, lots of math, will need to look into pressure changes from opening and closing valves, piping diameter will be different for each cylinder, longer piping slightly narrower to start. This will increase airflow velocity and overall volume to that cylinder vs equal size, this will ensure all cylinders receive equal air.

Large Plenum, equal runners
Pros - better application for turbo/boost, the plenum acts as a surge tank for when the valves open and close (pressure not released by the bov) These will have the shortest runners possible
Cons - my goal is more for a NA vehicle, but this is something to consider.

BGTV8 · 11-24-2014, 11:44 PM

Take a peek at the Jenvey site in the UK .. here:

Throttle Body Selection with Jenvey Dynamics - Jenvey Dynamics

There are a plethora of factors that influence induction system design, none-the-least of which is intake runner length - for an NA engine.

There is no doubt that longer runners generally improve torque and shorter runners improve throttle response, so that is trade-off #1

There is also the trade-off between ultimate power at 9 gazillion rpm and the ability of the induction to support optimum engine acceleration at or around peak torque

If you are not already familiar with induction system design, I suggest you prepare to spend a significant time on the web researching.

The other point is that the induction for a full-race engine will be a pig on the road - it will p155 and f4rt on the road and generally not be tractable, BUT it will howl like a banshee between peak torque and peak HP.

The other extreme can offer monster torque in the low/mid-range but have the engine fall off a cliff when the rpm rises.

Be prepared to do lots of work on the dyno unless you have access to CFD tools and can map your chosen design to do the research in the virtual world.

None of this stuff is simple !!

Jordo! · 11-25-2014, 05:59 AM

Have you got or can you build a flow bench? That alone would be a good starting point to see where you have room to make improvements in cfm.

On a related note, if you haven't already played with some calculators, check these out!

http://www.wallaceracing.com/runnertorquecalc.php <-- this one is especially handy if you have measurements on the OEM runners -- start from there and see where you can make changes.

https://www.rbracing-rsr.com/runnertorquecalc.html

http://www.bgsoflex.com/intakeln.html

Some very useful tips and maths here too
http://www.team-integra.net/forum/bl...culations.html

ViCiouS · 11-25-2014, 07:25 AM

Quote:

Originally Posted by BGTV8

If you are not already familiar with induction system design, I suggest you prepare to spend a significant time on the web researching.

Be prepared to do lots of work on the dyno unless you have access to CFD tools and can map your chosen design to do the research in the virtual world.

None of this stuff is simple !!

Quote:

Originally Posted by Jordo!

Have you got or can you build a flow bench? That alone would be a good starting point to see where you have room to make improvements in cfm.

Thanks for the links guys. I'm fully prepared for lots of research and always considering advice/comments. Otherwise it would just turn into dumping money into a crap shoot as Kinetic did...

I do not have a flow bench yet, but I DO have full CFD tools.

One thing I haven't seen anywhere yet:
When a valve closes, obviously the air that was accelerating towards the opening will rebound and send a pressure wave back towards the plenum (the point of a plenum to start with). Ideally I would think the runners should be tuned so that this wave is reaching the plenum at the same moment an alternate valve is opening, thus creating a minimal boost in pressure going to the next cylinder. This may only be optimal at a peak rpm or range though as the pressure wave frequency changes based on rpm and vacuum.

Jordo! · 11-25-2014, 02:04 PM

Quote:

Originally Posted by ViCiouS

Thanks for the links guys. I'm fully prepared for lots of research and always considering advice/comments. Otherwise it would just turn into dumping money into a crap shoot as Kinetic did...

I do not have a flow bench yet, but I DO have full CFD tools.

One thing I haven't seen anywhere yet:
When a valve closes, obviously the air that was accelerating towards the opening will rebound and send a pressure wave back towards the plenum (the point of a plenum to start with). Ideally I would think the runners should be tuned so that this wave is reaching the plenum at the same moment an alternate valve is opening, thus creating a minimal boost in pressure going to the next cylinder. This may only be optimal at a peak rpm or range though as the pressure wave frequency changes based on rpm and vacuum.

intake valve timing can be tuned quite a bit, so you may have a good bit of wiggle room there. It might be worth seeing if someone with the protuner cable can datalog some info you might be able to use as a reference point.

Actually, on that note, as you get a prototype or two built, I'd definitely see if you can team up with someone who has/borrow a protuner cable.

11-19-2014, 06:59 PM	#4 (permalink)
vividracing The370Z.com Sponsor Join Date: Jun 2009 Location: Gilbert, AZ Age: 38 Posts: 7,306 Drives: 350Z,370Z,GTR Rep Power: 39	Just a thought, but i came across this, and wanted to give you a heads up.. You might wanna pick this up GTR Intake collector and cover __________________ Rocky @ Vivid ♦ 480.966.3040 x236 ♦ Rocky@vividracing.com Email, PM, or call me directly for aggressive The370Z.com member pricing!!!

11-24-2014, 10:36 PM	#7 (permalink)
ViCiouS Base Member Join Date: Nov 2013 Location: Tampa Posts: 207 Drives: '14 981 Cayman S Rep Power: 12	^ that was gains from headers and manifold. Still no real knowledge on manifolds alone. :/ Well anyways I got my manifolds off yesterday, started doing some measurements and such on breaks from installing headers (a pain in the * to do alone btw, passenger done, drivers side getting done sometime this week). Got to thinking about what options for manifolds can be made and what will be most efficient. Equal length manifolds Pros - easiest to design, equal air to all cylinders Cons - more bends in piping, reducing efficiency Shortest runners direct from TB Note - a smaller plenum with short runners is also an option to help with harmonics of opening and closing valves Pros - least bends, probably most efficient Cons - very difficult to design, lots of math, will need to look into pressure changes from opening and closing valves, piping diameter will be different for each cylinder, longer piping slightly narrower to start. This will increase airflow velocity and overall volume to that cylinder vs equal size, this will ensure all cylinders receive equal air. Large Plenum, equal runners Pros - better application for turbo/boost, the plenum acts as a surge tank for when the valves open and close (pressure not released by the bov) These will have the shortest runners possible Cons - my goal is more for a NA vehicle, but this is something to consider. Jordo! and Eclipz like this. __________________ 2014 Cayman S - Daily and Track - PDK \| PSE \| SC \| PCM \| H&R \| HRE 2009 Ducati 848 - Weekend and Track - HMF \| Ohlins \| Microtec \| Woodcraft \| ASV 2010 370z Sport - SOLD -** KWv3 \| SPC \| Stance Wheels \| Z1 \| Stillen \| FI \| Takeda \| Uprev Last edited by ViCiouS; 11-24-2014 at 10:50 PM.

11-24-2014, 11:44 PM	#8 (permalink)
BGTV8 A True Z Fanatic Join Date: Dec 2009 Location: 03350 Australia Posts: 1,515 Drives: 09 Nissan 370Z M6 Rep Power: 39974	Take a peek at the Jenvey site in the UK .. here: Throttle Body Selection with Jenvey Dynamics - Jenvey Dynamics There are a plethora of factors that influence induction system design, none-the-least of which is intake runner length - for an NA engine. There is no doubt that longer runners generally improve torque and shorter runners improve throttle response, so that is trade-off #1 There is also the trade-off between ultimate power at 9 gazillion rpm and the ability of the induction to support optimum engine acceleration at or around peak torque If you are not already familiar with induction system design, I suggest you prepare to spend a significant time on the web researching. The other point is that the induction for a full-race engine will be a pig on the road - it will p155 and f4rt on the road and generally not be tractable, BUT it will howl like a banshee between peak torque and peak HP. The other extreme can offer monster torque in the low/mid-range but have the engine fall off a cliff when the rpm rises. Be prepared to do lots of work on the dyno unless you have access to CFD tools and can map your chosen design to do the research in the virtual world. None of this stuff is simple !! Jordo!, Rusty and ViCiouS like this.

11-25-2014, 05:59 AM	#9 (permalink)
Jordo! A True Z Fanatic Join Date: May 2010 Location: nirvana Posts: 6,394 Drives: 2023 NATM Rep Power: 418	Have you got or can you build a flow bench? That alone would be a good starting point to see where you have room to make improvements in cfm. On a related note, if you haven't already played with some calculators, check these out! http://www.wallaceracing.com/runnertorquecalc.php <-- this one is especially handy if you have measurements on the OEM runners -- start from there and see where you can make changes. https://www.rbracing-rsr.com/runnertorquecalc.html http://www.bgsoflex.com/intakeln.html Some very useful tips and maths here too http://www.team-integra.net/forum/bl...culations.html ViCiouS likes this. __________________ Enjoy it. Destroy it. Last edited by Jordo!; 11-25-2014 at 06:15 AM.

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11-19-2014, 11:33 PM	#6 (permalink)
Eclipz Enthusiast Member Join Date: Dec 2013 Location: Tampa Posts: 360 Drives: 06 Eclipse GS Rep Power: 12	Avery370z got his manifold extrude-honed, got decent gains after tune. Lower intake

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