KA24DE(R) (Supercharged) Thoughts?

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KA24DE(R) (Supercharged) Thoughts?

Postby zdonner on Wed Nov 30, 2011 5:42 pm

So, looking into it more and pricing being rather reasonable, does anyone here have any thoughts about Supercharging the KA?

http://www.ka24der.com/
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby LoFoSho on Wed Nov 30, 2011 6:58 pm

You need to talk to GrantSpec. He has a supercharged KA.
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby orion on Wed Nov 30, 2011 8:35 pm

Turbo's are a better choice, in almost every respect.

That's not to say superchargers are bad...and the new ones are as efficient as turbos (the compressor, not the whole system). The 4-lobe TVS rotors are impressive.

But you're not gonna have the option of a TVS charger on your KA. It'll be an older, MUCH less efficient unit...with no available aftercooling.

So compare to a low-dollar turbo setup (like a SR T28 on a bottom mount manifold - which I also DO NOT recommend)...it's gonna require more fuel and less timing = less power.

In order of the "best choices for a forced induction KA" -->

...LEAST DESIRABLE---------> ---------> -----------> -----------> -----------> ------------> MORE DESIRABLE.........................
....supercharger.............T25/T28 turbo setup..........straight T3 KA-T....T3/T4 KA-T......(insert BB turbo here) KA-T.....

...

In short - They are "neat", and different. Grant's setup is awesome.

But to make reliable, repeatable power...with more room for error...then a basic turbo setup will be a better choice.

That's my unsolicited advice.

- Brian
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby zdonner on Thu Dec 01, 2011 10:19 am

My train of thought on the matter revolves around the fact I found a 91 Hatch with very low miles and a KA that runs like a champ, so I thought I should have some fun witht he KA before it is removed for the RB25 that will ocupy the front end of my car. I've had an RB and SR 240 in the past, but have never had the KA for anything more than to drive the car home. I expect the KA with a twinscrew to make very good torque within the stock powerband so it should be a fun car to take on a curvy road or to an AutoX. I'm looking for at or a little north of 300RWHP so with a set of pistons, a mild cam, a smaller pulley (~12-14PSI) and supporting fuel system this should be an easy goal for a KA.
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby ConeDodger240 on Thu Dec 01, 2011 10:44 am

if you wana have fun, and save money for your future RB sheananagins, go with a simple turbo setup...or really have fun and put some nasty aggressive cams in it and high comp pistons
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby orion on Thu Dec 01, 2011 3:25 pm

zdonner wrote:... I'm looking for at or a little north of 300RWHP so with a set of pistons, a mild cam, a smaller pulley (~12-14PSI) and supporting fuel system this should be an easy goal for a KA.


Even 14psi from a supercharger isn't gonna get you there, I'm afraid. At least not on pump gas.

The tuning will have to be so conservative for that kind of boost, non-intercooled and from a not very efficient compressor...that you'll be lucky to see +260rwhp.

I'd bet you could eek out around 8-9rwhp per psi with some aggressive tuning. A mildly tuned KA-T setup will do an easy 11-12rwhp per pound of boost...if that puts the efficiency into perspective.

The only one I've seen that has been even semi reliable...was the car that 'klattr' bought (the one featured on the KA24DE-R site). It was making a reliable 240rwhp, I believe...although there is a 255rwhp dyno on that website (???).

Again, it's not that it's not a cool idea...or even wouldn't be fun. I'm sure it would be.

BUT, there are MUCH better ways to make power with a KA. Easier, too. Supercharging is the hard, expensive way to go.

...

Food for thought, that's all.

- Brian
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby zdonner on Fri Dec 02, 2011 11:48 am

orion wrote:So compare to a low-dollar turbo setup (like a SR T28 on a bottom mount manifold - which I also DO NOT recommend)...it's gonna require more fuel and less timing = less power.


Actually you would advance the timing more than likely to increase the LSA when tuning.

Also I would like to note that when comparing the M62 setup to a T28 you would be spending more money for less power.

The Maximum flow for a T28 is 448CFM
For comparison @ 10psi this would put out about 25lbs/min

Volumetric Efficiency is ~65% @ 10psi - Granted this would be ~77% @ 14.7psi

The Maximum flow for a M62 is 586CFM
The M62 @ 10psi puts out about 35.79lbs/min

Volumetric Efficiency is ~92% @ 10psi at my estimated 14465 RPM with a stock 6500 RPM redline on the KA. VE is about 86% (conservatively) @ 14psi

I'm still working all this out but according to Eaton my goal of 300rwhp is ascertainable. Granted this would require a good cam, lower comp pistons, and tune as well as a proper exhaust manifold.

Though I would like to add that any more than about 300RWHP and you are better off with a bigger blower as you cannot push a M62 beyond ~14(.5) psi as the revolutions exceed what is commended for the supercharger.
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby Curbitis on Fri Dec 02, 2011 12:17 pm

Why would you lower the comp with a SC? It's not like you are running crazy boost with it.
As far as reaching 300 whp (with a 62) that just seems like a very very big goal.
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby zdonner on Fri Dec 02, 2011 12:23 pm

I find it best to have goals, even if they are a little out there.

Only after checking with Eaton do I feel 300/whp is a real goal. Also using thier calculator dropping the compression gave a good gain. I'm still very early into the planning on this build but 250whp is bolt on so to pick up 50hp using 4psi more, a cam, header, water/meth, and a tune I think is possible.


Now granted, this is using the M62 to its absolute limits. Which is an issue and why it may become a M90 but still NEARLY 300*RWHP* from a M62 on a KA is theoretically possible.

This is the Chart I created today. The areas in red exceed the operating parameters for the M62 according to the manufacturer.
M62 Chart.jpg
M62 Chart.jpg (80.84 KB) Viewed 2181 times
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby Curbitis on Fri Dec 02, 2011 12:43 pm

Ehhh also.. injector size?? Overall, If you could do a 62 to 300whp I will commend you sir ;)
Will a 90 even fit under the hood?? Also, in the red, I assume thats the point of operational failure? I wonder
how much heat that's producing and will the heat just have adverse effects (regardless of cooling) on the
performance you're trying to get. Now I'm freaking curious... grrrrr
Last edited by Curbitis on Fri Dec 02, 2011 12:46 pm, edited 1 time in total.
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby zdonner on Fri Dec 02, 2011 12:45 pm

Temperature is the only factor I've not been able to add to my calculations as of yet, to spin a M62 @ 14500 RPM it will cost 35HP according to Eaton a KA24DE at 8.5:1 comp (other wise stock) could make 362 Flywheel HP.

Per Eaton;

EnginePower 362.638 Hp
EnginePressureRatio 1.992
EngineSpeed 5400
EngineTorque 478.206 Nm
SuperchargerPower 33.276 kW
SuperchargerTorque 23.077 Nm
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby zdonner on Fri Dec 02, 2011 12:48 pm

Curbitis wrote:Ehhh also.. injector size?? Overall, If you could do a 62 to 300whp I will commend you sir ;)
Will a 90 even fit under the hood??


Not sure on the M90, I've not gotten dimensions for it yet but it looks to be close in size. Injectors are not a worry right now :)

This is all numbers and logic right now, but everything I'm seeing says it's possible. Heat is the 800lbs gorilla in the room and could be the reason for it not to reach 300 RWHP.

I would like to note this with some Standard conversion....

EnginePower 362.638 Hp
EnginePressureRatio 1.992
EngineSpeed 5400
EngineTorque 478.206 Nm ***(353 ft/lbs)*** Gotta love a KA.
SuperchargerPower 33.276 kW
SuperchargerTorque 23.077 Nm
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby anti tyler on Fri Dec 02, 2011 3:04 pm

my question is, if your ultimate goal is to go RB, why are you putting so much thought into this whole supercharged KA ordeal? save your money and have fun when you build an RB? it just makes more sense to me. but hey, do whatever you want to do.
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby zdonner on Fri Dec 02, 2011 3:08 pm

I may actually put the RB in another car; also I just want to do something with the KA which is fueled by the possibility that this will be a blast to build/drive.
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby orion on Fri Dec 02, 2011 3:37 pm

You've done the math, and considered more things than most of the "I'm gunna soup-err-charge my KA!!!!" guys.

However...

zdonner wrote: Heat is the 800lbs gorilla in the room and could be the reason for it not to reach 300 RWHP.


That's it. THE problem.

You mentioned meth/water, and that might make the difference. But more complex = less reliable, in most cases.

I'll say again - I'd LOVE to see you get this running, tuned, and making reliable power. But there have been a number of people so far that have attempted it, and none have lived up to expectations.

...

zdonner wrote:
orion wrote:...it's gonna require more fuel and less timing = less power.


Actually you would advance the timing more than likely to increase the LSA when tuning.


Just a note - I'm talking ignition timing here.

- Brian
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby zdonner on Fri Dec 02, 2011 4:04 pm

Water injection is going to be key, at this point I don't forsee detonation being an issue with this. What I really need to do is find record of someone with a modified head and aftermarket cam setup that's had it on a flow bench.



orion wrote:You've done the math, and considered more things than most of the "I'm gunna soup-err-charge my KA!!!!" guys.


I don't like half-assing anything; this will still be a "temp" project unless I decide I really want to keep it. I like to plan rather than throw money at a car.
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby GrantSpec on Fri Dec 02, 2011 4:12 pm

orion wrote:...LEAST DESIRABLE---------> ---------> -----------> -----------> -----------> ------------> MORE DESIRABLE.........................
....supercharger.............T25/T28 turbo setup..........straight T3 KA-T....T3/T4 KA-T......(insert BB turbo here) KA-T.....


I'd take my supercharged KA over a T25/T28 setup any day. Brian I think you will agree once you drive my car (Or should I let you after all of this hate talk? :lol: )

Also, I doubt an m62 will ever make more than around 250 on a KA without an intercooler; 300 is definitely a lofty goal.
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby zdonner on Fri Dec 02, 2011 4:19 pm

Grant,

I keep hearing that, so I would look to you and ask; heat? Detonation?: without one you won't have the other and without enough of the first I think it can happen. What supercharger are you using? Stock head? Pulley diameter? The M62 can flow the air, now if it's super-heated then I could fall short.
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby GrantSpec on Fri Dec 02, 2011 5:00 pm

I'm running an m62 non intercooled. The belt runs on the alternator portion of the crank pulley and the supercharger has a stock pulley. Im seeing 10-11 psi of boost at full throttle. Stock head as well. I don't seem to be getting detonation. I ran an auto-x over the summer on a very hot day and heard no rattles. As for the charge temps, they definitely get hot. My IAT will read over 220 F after several hard pulls. I will run some data logs of the IAT temp with MAP overlay this weekend and post it here.
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Re: KA24DE(R) (Supercharged) Thoughts?

Postby zdonner on Fri Dec 02, 2011 5:41 pm

GrantSpec wrote:... I will run some data logs of the IAT temp with MAP overlay this weekend and post it here.


You're the man! Thanks!

If you get a chance would you mind dropping me an e-mail?
zdonner179@gmail.com
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