new custom inatake mani watcha think

[sil80forme]

well basically myself and a friend (Skatanic 28)were talkin online bout doin a ITB setup with custom plenum so i wouldnt have to use a standalone.. so he pretty much came up with this design. but since the ITB's with plenum had been done i just went ahead and had plenum made



so i took the design to the local machinist gave him my specs and a week latter i got this.. well i have been runnin it for about 2 weeks now with no major probss. i am not using egr, aic, or the aac. its bare intake mani with 2 nipples for the brake booster and fpr check it out let me know what u think

[NemeGuero]

Not to hate.. but did you flow test that thing? Optimize flow rates/cylinder?

Or just make it kinda angled and put 4 tubes in it as an AutoCAD practice?

[Fat Felix]

how did performance improve or not improve?

[sil80forme]

no flow testing.... i know i know, but it didnt hurt anything from what i can tell driving it on the street. i actually think it helped throttle response, and torque. for a NA ka she moves pretty good. if i ever get the money to get her dynoed i will post of some #'s. p.s i really noticed a difference at the local track where we have weekly drift sessions. its definitly easiar then before with stock mani.. but like i said the dyno will tell all.

[mjjstang]

catia ftw...

[sil80forme]

CATIA? i dont understand

[jrmiller84]

Was the cost of the machinist and your time less than the cost of just buying a nice Greddy (or other) intake plenum? I'm all for DIY but don't sacrifice your engine or funds when it could be done for about the same (maybe) with a much nicer/safer/efficient outcome. Good work either way, just be careful.

[sil80forme]

yeah cost was 200 dolars total for machinist... and took about an hr to install..

[projectdrifter]

the manifold design would be nice if u utalized the stock runners. nissan had designed the runners from factory to optimize atomization of the air going into the intake tracks. velocity stacks might have helped out as well. yes your car does drive/respond diffrent with the new setup. i have driven the car with stock manifold and the modded manifold he has on now. the rsponse has changed but seat of the pants dyno results are quite bias.

on a side note nick. ur long studs came in today.

[sil80forme]

Originally Posted by projectdrifter

the manifold design would be nice if u utalized the stock runners. nissan had designed the runners from factory to optimize atomization of the air going into the intake tracks. velocity stacks might have helped out as well. :

blah blah blah optimize atomization blab blah blah, its all nonsense if u ask me lol
i dont care. its works! i like it and when its a ka-t, i'll like it even more

[JDMClifford]

correct me if im wrong but that setup would only give you hp at high rpms? dont longer runers give you more torque? so you could have lost torque and gained a small hp at redline? like this chrysler manafold

[Team Rootbeer]

wow. by machinist do you mean a chimp with a tig machine and a cutoff wheel?

not very quality if you ask me.

[reflexdb]

Doesn't look too bad. Velocity stacks definitely would have been a good idea. I doubt runner length will change much at all, as that's been my experience. Volume of the new manifold is smaller than the stock manifold right? That would explain the improvement in throttle response.

By the way, AutoCAD is ancient! BitTorrent yourself some SolidWorks 2007 brah.

[NemeGuero]

SW> ProE > autoCAD

[kandyflip445]

Originally Posted by jrmiller84

Was the cost of the machinist and your time less than the cost of just buying a nice Greddy (or other) intake plenum? I'm all for DIY but don't sacrifice your engine or funds when it could be done for about the same (maybe) with a much nicer/safer/efficient outcome. Good work either way, just be careful.

I thought Greddy only made a intake manifold for the SR.

Originally Posted by projectdrifter

the manifold design would be nice if u utalized the stock runners. nissan had designed the runners from factory to optimize atomization of the air going into the intake tracks. velocity stacks might have helped out as well. yes your car does drive/respond diffrent with the new setup. i have driven the car with stock manifold and the modded manifold he has on now. the rsponse has changed but seat of the pants dyno results are quite bias.

Shouldn't atomization be primarily be handled by the design of the injector? I know the slight rough finish on the inside of intake runners is thought to help with atomization but how much does it really effect? I would imagine that it would primarily help with preventing detonation because of the air/fuel mix being more evenly mixed when it enters the combustion chamber.



Did you dyno the car before installing the manifold? If you didn't it would be nice if you installed the stock manifold and ran that on a dyno and then do the new manifold on the dyno to have a comparison and be able to see where you made/lost power and what not.

[GSXRJJordan]

I like it. Of course, I've got a gsxr750 ITB setup sitting in my garage, and actually need a plenum like that to use em.

As far as runner length, it looks very close to ideal, but yes technically longer runners improve midrange, shorter runners improve top end. With an engine as relatively large and untuned as the KA (as opposed to a sportbike engine), you could double the length of the runners and probably not see an improvement on the dyno.

In regards to atomization, the injectors atomize almost perfectly - it's the trip from the injector to the combustion chamber where you have problems. What happens if you have a long, smooth runner is the fuel starts to puddle together (think how water drops on your windshield pool together), and that makes for a slower, more uneven detonation. Again, we're talking about a KA truck motor here, not a gsxr1000 superbike motor, so the difference is small, but still.

Good luck getting him to install the old mani again before hittin the dyno lol.

[GSXRJJordan]

hahaha - poster neg-repped me for saying the KA's a truck engine. You're trying to say it's closer to a superbike motor than a truck motor? I didnt even bomb on your manifold like other people did... lol

[sil80forme]

Originally Posted by JeffMilano

hahaha - poster neg-repped me for saying the KA's a truck engine. You're trying to say it's closer to a superbike motor than a truck motor? I didnt even bomb on your manifold like other people did... lol

hey i appreciate that... but i wasnt the one who neg-repped u...

p.s if i ever get a chance to goto the dyno i will reinstall the factory mani... it only takes 30min tops to remove/install it

[EAGLE 5]

Perhaps an oversimplistic observation. But wouldn't part of your increase in performance be related to the removal of the EGR? or were you running without it in the stock KA manifold.

Just curious.

[TipStylez]

Should of done this first.

http://ka-t.org/intakemanifoldbasic.php

[kandyflip445]

Originally Posted by JeffMilano

I like it. Of course, I've got a gsxr750 ITB setup sitting in my garage, and actually need a plenum like that to use em.

As far as runner length, it looks very close to ideal, but yes technically longer runners improve midrange, shorter runners improve top end. With an engine as relatively large and untuned as the KA (as opposed to a sportbike engine), you could double the length of the runners and probably not see an improvement on the dyno.

In regards to atomization, the injectors atomize almost perfectly - it's the trip from the injector to the combustion chamber where you have problems. What happens if you have a long, smooth runner is the fuel starts to puddle together (think how water drops on your windshield pool together), and that makes for a slower, more uneven detonation. Again, we're talking about a KA truck motor here, not a gsxr1000 superbike motor, so the difference is small, but still.

Good luck getting him to install the old mani again before hittin the dyno lol.

But isn't the injector almost a straight shot into the head? If it's that close and it's timed correctly then why would it have a chance of starting to puddle. It would make sense on a carbed engine where the fuel is introduced much earlier in the intake path but not in a fuel injected engine like the KA.

[wootwoot]

This is fucking stupid. To hell with some of you criticising this much. A more respected member(someone with more post count) did this same thing and people ate it up like it was vagina. DIY is fucking awesome and its great that you did this. It might not be perfect but since when is anything without an engineering budget the most proper way. Good frickin show and pleasseee get the dyno part worked out.

[drift freaq]

Originally Posted by JeffMilano

Again, we're talking about a KA truck motor here, not a gsxr1000 superbike motor, so the difference is small, but still.

Good luck getting him to install the old mani again before hittin the dyno lol.

Well I have to say that they should not have neg repped you. Though your above statement is completely ignorant. The so called truck engine was the KA24e which was actually assembled in Mexico and had different torque and hp specs with a throttlebody injection i.e. hybrid carburetor. Completely different from the KA that came in our cars, which is also different from the FWD KA that came in Altima's.
Statements like yours lead to the internet myths that are so prevalant these days.
I should add that while we are on the subject of truck motors . Toyota, Honda,Nissan all cross reference their engine platforms across the product line. To just randomly call the engine a truck motor without proper knowledge is the kind of thing Craig Leiberman would and did say. You want to be cast in the light of Craig Leiberman? its up to you.
Can we say F&F1 and Sport Compact car? Great places for accurate knowledge. Eh NOT!

oh and to not veer completely off topic that manifold while interesting would need to be flowbenched to see if it was worthwhile.

[kandyflip445]

What's FF1?


jklsdjal;jd

[S14DB]

Why not a Q45 Throttle Body?

[chibo]

Originally Posted by wootwoot

This is fucking stupid. To hell with some of you criticising this much. A more respected member(someone with more post count) did this same thing and people ate it up like it was vagina. DIY is fucking awesome and its great that you did this. It might not be perfect but since when is anything without an engineering budget the most proper way. Good frickin show and pleasseee get the dyno part worked out.

Damn son, better than I could have said it +Rep for taking the initiative and building something of your own design Interested in seeing dyno results and further projects

[wootwoot]

I made a booboo.

[Crono562]

Hey goodjob. Forget the opinions of others. Few people would take the initiative to go and design and then have something like this made. Its impressive work. If you get the chance though you should have it flow tested though, that way you could go back and improve your design if you wanted to. Keep up the goodwork!

[EAGLE 5]

Originally Posted by S14DB

Why not a Q45 Throttle Body?

I was going to suggest that too! those throttles are pretty damn big, would probably do wonders in a custom intake setup unless of course you rig some ITBs

[GSXRJJordan]

Originally Posted by kandyflip445

But isn't the injector almost a straight shot into the head? If it's that close and it's timed correctly then why would it have a chance of starting to puddle. It would make sense on a carbed engine where the fuel is introduced much earlier in the intake path but not in a fuel injected engine like the KA.

Without straying too far here, the injector is placed as close as it can be, but you still want that nicely-atomized spray from the injector to swirl and mix as evenly as possible, so that's why the injector isnt actually "on" the head/closer/etc. Anyway, the point is, it doesn't truely matter until you get waaaaaay closer to the "edge" of tuning (aka Superbikes).

The KA/truck motor thing isn't so much saying that the KA out of a car could have been in a truck in a past life, etc... it's more of a comment about how de-tuned it comes from the factory, compared to something that's tuned to the absolute legal limit, like a bike. Do with it what you will ~ this thread reminded me to re-download solidworks for my laptop btw