ITB's + GT32 = Fun!

[NemeGuero]

Lets plant one...

[hitman]

he doesnt rev high
he doesnt need rods
usually on a boosted motor number 4 gets more air
and where is the naked pics!

[BigVinnie]

Originally Posted by hitman

he doesnt rev high
he doesnt need rods
usually on a boosted motor number 4 gets more air
and where is the naked pics!

Actually past 7000RPM is high rev for a KA, he want's to take it to 7200RPM with no drop off in power.
He does need rods he is using a GT32 and injectors that can easily make him 600WHP....
With what proof do you have that number 4 gets more air?
Blah!!!!!!! Not worth my time to argue in Scotts thread....

[ranisron]

Vinnie, As far as I remember, out of all the second gen altima (98-01), 00 piston and rings are your best friend. Some of the DET guys on altimas.net were boosting pretty nicely on the 00 engine. Stay away from 98/99/01.

Best of luck Scott. Get the build going and we will be waiting patiently for some awesome results.

[BigVinnie]

Originally Posted by ranisron

Vinnie, As far as I remember, out of all the second gen altima (98-01), 00 piston and rings are your best friend. Some of the DET guys on altimas.net were boosting pretty nicely on the 00 engine. Stay away from 98/99/01.

Originally Posted by Gabe Z (DeviousKA) Manager of HybridKA.com

From 1998 on (excluding 1998 240sx) Nissan produced only one piston for both the Altima and Frontier/Xterra. This piston has the difference in ring assortment i mentioned above, as well as a very minute increase in the piston dish volume (I forgot about this in earlier post but difference is miniscule). This lowers the compression slightly from 9.5:1 (98 and earlier 240sx, altima) to 9.2:1

The rings are not interchangable between pre 98 pistons and 98+ pistons. .25mm difference in thickness for both compression rings and .3mm thickness difference in total oil ring. Also the oil ring depth is different, 3 different depths changes starting in the 95-97 altima (although these used earlier type compression rings).

I am well aware of all KA24DE differences in casting and components. There are actually 7 different KA24DE cylinder head castings including those cast in japan, mexico, and USA. Some are only minor differences.

As far as pistons, with sohc and dohc combined, there is 8 different oem offered pistons.

Gabe will sell you the pistons with an overbore if needed 98-2001 pistons are all on the same production.
My brain is a sponge when it comes to KA information I memorize quotes, as well as information from the FSM, and tech info that I have done myself.

[ranisron]

Vinnie,

Thanks for the info

Ron

[RBS14]

About the plenum design. So you're saying with a full radius stack that would deflect airflow above or below its opening upon entry into the plenum would over feed #1 but a design that shot air directly into cylinder #'s 1 and 2 wouldn't over feed them? what kind of sense does that make? The plenum doesn't taper for a good reason, because I want all of the stacks to have the same area of air above them and same proxemity to any walls so they can all get the same amount of air. If you just have runners going off the bottom of the plenum floor to the engine without any velocity stacks you need to reduce the possible amount of air each successive cylinder is getting because you will get losses on each cylinder as the air travels back. This is not the case with velocity stacks sitting above the floor, in the air stream. At any rate, we're going to try doing this with the stock motor again, and trim #1 10% (more fuel) and see what happens.

[BigVinnie]

Originally Posted by RBS14

So you're saying with a full radius stack that would deflect airflow above or below its opening upon entry into the plenum would over feed #1 but a design that shot air directly into cylinder #'s 1 and 2 wouldn't over feed them?.

I didn't say that.

Originally Posted by RBS14

The plenum doesn't taper for a good reason, because I want all of the stacks to have the same area of air above them and same proxemity to any walls so they can all get the same amount of air. If you just have runners going off the bottom of the plenum floor to the engine without any velocity stacks you need to reduce the possible amount of air each successive cylinder is getting because you will get losses on each cylinder as the air travels back. This is not the case with velocity stacks sitting above the floor

Whats wrong with a tapered plenum? Tapered plenums (I call em cone shape) are made to evenly distribute the air flow to feed each cylinder. When you are running low boost or are spooling, tapered plenums work most effectively to allowing the engine to take what it need's until enough pressure builds in the system. Tapered plenums allow the molecules to spread evenly along plenum even during the point in time in which they compress in the plenum chamber during boost. You do need to realize though as pressure builds so does the effect of valve overlap, and scavaging.Increasing boost pressure only increase the momentum of the intake charge allowing for alot of o2 to pass right through past the intake and exhaust valves. So there really isn't 8PSI of boost pressure in the plenum, even if you run boost at 8PSI, air is constantly moving it's way through the cylinder and through the exhaust.
In your case it almost sounds as if you wanted to apply constant pressure to your plenum. That isn't the case as there is spool time to where the engine can infact consume more air than what is given from the turbo at low spool.
Since the dynamic of pressure is to look for the nearest closest exit (if you built a hallway and were trapped what door would you go through first) hopefully an easy analogy to understand.
Much appoligies Scott if you think I am trying to offend you, I only want to help in better your project.....

[Johny5]

Originally Posted by BigVinnie

Much appoligies Scott if you think I am trying to offend you, I only want to help in better your project.....

.


I don't think the plenum is big enough to get air to the number #4... and with the way the manifold inlet comes in I could see it overfeeding #1.


Whatever, we'll find out when you run an A/F on each cylinder.

-McRussellPants

[NemeGuero]

Maybe you can flow test the manifold and see?
I know there's a software that does it, we use it for our FSAE car.

Scott, if you want to send me dimesions and stuff of your manifold I can see if we can put it up on the computer at school...

[RBS14]

Vinnie, I may have come off a little harsh there. I know you're trying to help. some air escapes through the exhaust via overlap, but not much. The reason overlap is present is to actually create more of a pressure differential between the intake manifold and the cylinder, thus sucking in more air, increasing VE a bit. Only a very small amount of air escapes into the exhaust. You do actually have a positive pressue in the manifold. That's precisely what boost is. Unless you get the taper in the plenum exactly right, you are going to create a different VE in every cylinder. The only way to get it correct would be extensive design via fluid dynamics and testing. The next best way I can see is expose all of the cylinders to as close as possible to the same conditions. The best way to do this is to have the air flow come in exactly 90* to the runner direction so it can equalize and distribute evenly. Especially if you have a mechanism that helps to reduce losses to each cylinder as the air feeds in.

Who knows. It's all shit none of us really fully understand anyways. haha

I'm just going to throw another stock motor in it, trim #1 10% (in case you guys are right and it is going lean) and try again.

[BigVinnie]

Originally Posted by RBS14

Vinnie, I may have come off a little harsh there. I know you're trying to help.

It's all good man.
Really if it was me doing an ITB set up I would'nt even do a plenum design. I would of just made 4 equal length runners into a 4-1 design to seperate equal boost pressure to each runner/ITB.. It would pretty much look like a smaller version of a 4-1 exhaust header strapped to the intake/ITB's.....
If you don't get the richness down on cylinder 1, I would gladly help you weld a different style manifold.
I've been reading a book on fluid dynamics and plenum design, there are some pretty crazy contraptions you can make for your ITB setup, your not just bound to plenums.
No need to apoligize Scott everyone thinks I'm an asshole in the forums till they meet me in person, no offence taken. Keep up the excellent work.

[NemeGuero]

Originally Posted by BigVinnie

No need to apoligize Scott everyone thinks I'm an asshole in the forums till they meet me in person, no offence taken. Keep up the excellent work.

I met him.. and he's STILL an ass! HAHA j/k

[EchoOfSilence]

Originally Posted by BigVinnie

It's all good man.
Really if it was me doing an ITB set up I would'nt even do a plenum design. I would of just made 4 equal length runners into a 4-1 design to seperate equal boost pressure to each runner/ITB.. It would pretty much look like a smaller version of a 4-1 exhaust header strapped to the intake/ITB's.....

YES!
That's exactly what I was thinking, but I couldn't put it on in words well enough to actually post it. I agree, Vin.

[RBS14]

Except with that design you have no extra volume of air when you snap the throttle wide open to fill the runners. You just get a void where the engine can't get enough air. That's one of the main reasons why we have plenums. The real trick is to make a plenum that is just big enough to supply the engine with enough air in that situation, but not so big that it induces a bit of lag or slugishness.

[nissantuner22]

Right, take a look at ARC's line of N/A performance parts. Their induction tubes have huge pockets for air, to increase throttle response in the situation RBS14 describes.

[wootwoot]

Could you link to that part you are speaking of Nissantuner?

[infinitexsound]

nice scooter at only 7 psi, i dont think scooter is doing anything wrong with his intake manifold setup at all.. granted u want one of those slanted design .. for more effective air flow... but i've seen a gt3 car run a squared shaped one.... with ITB.... im guessin u bought one of those ross racing kits they sell....

honestly the air flow u would want to look at is how it connect from the TB to the HEAD... if u notice inside the KA head how its curved... youd want a direct airflow that continues with good flow too the intake port.. scooter did this well by using the stock intake half of the OEM mani.... most guys just run like a straight setup to the intake port... that to me is not connecting well to the intake port.. and is not giving good flow... THINK CURVED inside the KA head.. and youll see what im trying to say....

SCOOTER GOOD JOB MAN @ 7psi... WOW

AND VINNIE i like u man... u know what ur talkin about...and have to balls to say whats on ur mind.... WHATS REALLY REAL? and WHAT IT DONT DO?

[RBS14]

Here's the sheet from our last two runs before the motor blew. I got a new one this afternoon and am going to go throw it in now.

wastegate spring in pink and first run with Haltech controlling it in red. 7psi at 2700rpms!:

[Lordrandall]

Originally Posted by RBS14

Here's the sheet from our last two runs before the motor blew. I got a new one this afternoon and am going to go throw it in now.

Good luck with the new engine. Dial it back just a little?

[nissantuner22]

[GlacierFreeze]

Any updates on this? New motor in and running yet? Did you ever swap in cams for that chart or were they stock?

Very nice TQ curve. Or should I call it a TQ plateau? haha

[yokotas13]

that shit his HOTT

[steve shadows]

xcellent write up so far for the ka crowd.

Im enjoying my E8 also btw.

you street tune? I street tune love the data logging.

[RBS14]

Been gone for a while. I got a new motor put in like 2 months ago and the oil seal went to hell when I tried putting my aluminum crank pulley on. The nub that the pulley lines up with dislodged and pushed into the seal. Just my luck. I was so sick of my car I took it to a buddy's place, and he let me keep the car in his garage in San Diego for the summer while I came back up to Norcal for the summer. I'm going to go back down to San Diego in 2 weeks for school and I'm gonna throw a new oil seal in it. It will then meet one of two fates:

1. I sell it.
2. I drive it back up to norcal and put it in my garage here and forget about it for a LONG time.

Luckily I've got a couple weeks to decide.

Just thought I'd update you curious folk.

[aNskY]

Originally Posted by RBS14

Been gone for a while. I got a new motor put in like 2 months ago and the oil seal went to hell when I tried putting my aluminum crank pulley on. The nub that the pulley lines up with dislodged and pushed into the seal. Just my luck. I was so sick of my car I took it to a buddy's place, and he let me keep the car in his garage in San Diego for the summer while I came back up to Norcal for the summer. I'm going to go back down to San Diego in 2 weeks for school and I'm gonna throw a new oil seal in it. It will then meet one of two fates:

1. I sell it.
2. I drive it back up to norcal and put it in my garage here and forget about it for a LONG time.

Luckily I've got a couple weeks to decide.

Just thought I'd update you curious folk.

i think if youre just gonna park it and forget it you should sell it. a car like that deserves to be driven!

[SpeedMonkeyInc]

Sounds like me Scooter. I am about to park my S14 and leave it in storage for a few years. I am sick of fixing it right now, I need to get other things in my life prioritized.
Good luck with whatever you decide!

[Mr. Camshaft]

I think what Vinnie was trying to say was that while the area above each TB may be the same, once the motor gets running, the air density over each changes. With that 90 degree setup for all four intakes, each progressive intake takes in less air. The difference may not be huge, but it's still there. You end up with a pressure/density gradient, not the equal distribution you were looking for.

[ramblux]

Damn Scott, sorry to hear about your luck with that engine. And sorry I didn't reply back to your PM to me on that "other" site -- I got a bunch of PMs that day and still haven't gotten back to all of them. I appreciate all the help!


And if you do decide to sell her (and I hope you don't), let me know how much you might be wanting for it.

And let's please get that thing shot when you're ready!

[articdragon192]

Hey, I couldnt PM you cause your inbox is full, but where did you get the velocity stacks you used on the plenum? I just got my ITBs but I need veolicty stacks so that I can have someone fabricate me a plenum for it.