KA24DE Build-up / need bigger Throttle Body!

[Rod]

Hey guys, I'm a newbie here at the forums and I'm hoping someone can help me out.

I'm looking for a bigger Throttle body that can bolt-on or be made to fit the KA24DE's intake manifold. Does anyone know of any other compatible TB from nissans bin or any other manufacturer? Also, anyone have any tricks on how to keep the factory MAF from seeing max voltage at high RPM's? Any help would be great!

I'm trying to get more power out of the KA24 - So far I reached 151whp and 157wtq with the following mods:

JWT re-programmed ECUInjen cold-air intakeHotshot headersApexi GT exaustUnorthodox Racing pullies kitFidanza flywheel

Not bad for just bolt-ons! I had the car dynoed and there is room for improvement at points throught-out the A/F ration curve.

Any help would be great!

Thanks,-Rod

[Ni2s4s0aSnX]

Well, welcome to NICO. I'm pretty sure that the 300zx throttle body is bigger than the 240sx throttle body, but don't quote me on that one. And there is one company who makes aftermarket throttle bodies for the 240sx, but I can't think of the name of it right now, just do a google search or something. I don't know about keeping the same MAF though. People take the MAFs from a 300zx or Ford Cobra because it can handle more.

[Dark-Hawk]

Stock MAF is good for about 350whp or so. No real need in changing it out now

[TrueSlide]

Z guys usually use KAE tbs for upgrades. Someone, I think it was bigvinnie, posted a place that offers TB boring. Around $150. If I recall a Q45 TB is a slightly bigger TB then the KAE.

edit: just realized you are talking about the DE. So Iam not sure on the TB.

[SimpleEnigma]

The stock MAF is only good to about 250-260whp before its no good. Guys running 260 and up generally use the Z32 TB or a Mustang Cobra TB, but the ECU has to be reprogrammed to use each.

Search Throttle Body Boring, and you should come up with a link for a service that will bore our stock 57mm TB out to like 70mm and includes a new throttle plate.

The q45 TB is 80mm and will work using the stock TPS, and any TB made for the SR20DET will work, and a TB from a 91-94 mustang 5.0 is 70mm and will bolt up, just use your stock TPS.

Or if you want to go nuts, you can convert to ITB's using the TBs from a suzuki GSXR750 or Gixxer 1000, and a custom stand alone ecu like MegaSquirt or Haltech.

[KADreams]

http://www.splparts.com/Parts/...t.asp

Scroll down to the Tomei oversized throttle body.

[ken81590]

how loud is that apexi gt spec

[Dark-Hawk]

The stock MAF is only good to about 250-260whp before its no good. Guys running 260 and up generally use the Z32 TB or a Mustang Cobra TB, but the ECU has to be reprogrammed to use each.

Search Throttle Body Boring, and you should come up with a link for a service that will bore our stock 57mm TB out to like 70mm and includes a new throttle plate.

The q45 TB is 80mm and will work using the stock TPS, and any TB made for the SR20DET will work, and a TB from a 91-94 mustang 5.0 is 70mm and will bolt up, just use your stock TPS.

Or if you want to go nuts, you can convert to ITB's using the TBs from a suzuki GSXR750 or Gixxer 1000, and a custom stand alone ecu like MegaSquirt or Haltech.

Hmm was under the impression the stock MAF was good for upwards of 350? I suppose not though. On a side note you don't *need* a reprogrammed ECU for the Z32 MAF you can go with a piggy back like the S-AFC II and be fine with the ECU "stock."

how loud is that apexi gt spec

It's pretty loud.
Modified by Dark-Hawk at 7:36 PM 1/11/2006

[SimpleEnigma]

Yeah....the stock maf quits at about 260whp, switching to the Z32 MAF is no biggie. they go for like $50 and you can either reprogram your ECU or go with a piggyback.

the GT Spec exhaust is 3" piping diameter correct? if so, it is going to be very loud, 3" exhausts are known to be quite loud on an N/A KA24DE, but if sound is not an issue and you are looking to squeeze every horsepower possible out of the motor...go for it.

[s14 2510's]

apexi gt is 3 3/4. I have it on my s14 with rb swap.

[9240sx]

The 300zx Throttle Body's are way smaller then the 240sx.The Q45 Throttle body is the one you want.

[Rod]

how loud is that apexi gt spec

It's not too loud... it's tolarable.... under high rpms - it screams, but with a very deep tone, very beast like... hehehe

[NateDogg]

Stock throttle body is not a flow restriction until 350hp.

[Skidmark]

1.) The GT Spec is not loud at all, IMO, at least with the cat still in place. The resonator on it is HUGE.

2.) Don't 300ZX's run 2 TB's? Thus they would be smaller.

3.) 80mm bolt on sounds quite nice

[daconkiftador]

The q45 TB is 80mm and will work using the stock TPS, and any TB made for the SR20DET will work, and a TB from a 91-94 mustang 5.0 is 70mm and will bolt up, just use your stock TPS.

The Q45 TB is 90mm, and do you have any link about 91-94 Mustang TB's bolting up and working? Let us know, caus 70mm does sound pretty good =)

[SimpleEnigma]

This was a thread that popped up not too long ago where the mustang 70mm TB upgrade was confirmed.

zerothread?id=149490

read a little lower on that thread and you will see that you really dont need to go a whole lot bigger than 70mm on the KA, even a built one.

[deviousKA]

The ka maf's may max out at those hp levels under boost, but they are still a restriction. The levels quoted are simply the point that the maf has reached 5v and can no longer provide a proper air flow signal to the ecu.

Go with a larger diameter maf, one that has good NA airflow resolution. The maf that falls under this category is the early 90's vg30e maxima maf, same diameter as the 300zx (iirc) but does not "support" as much hp because the hotwires capability maxes out sooner. This isnt a popular maf upgrade in the turbo croud for this reason, but you will get positive results with your NA combined with a larger throttle body. The q45 throttle would bit just a bit overkill.

It will require a retuned ecu obviously, and someone with the balls to actually modify their car without hearing someone has done it before. The turbo community knowledge has little to offer for those tuning NA, any dummy can make hp with pressure no matter how well the engine actually flows.

[spider_slayer]

is it jsut me or is a 70m tb overkill for a motor pushing under say... 400rwhp?

[daconkiftador]

I dont think its overkill, my buddy put a Weber 3" Throttlebody on his 1.8l VW Rabbit(gti), and NO it didnt give horsepower but it did make throttle response very very snappy and quick. Given this wasnt a stock 1.8l, intake, full exhaust, cam, and a couple other bolt-ons. When he put a stock throttlebody back on to compare, you could definently tell the difference.

[spider_slayer]

well, most ka's in this forum are competely stock. even with the few bolt-ons that the original poster has i'm sure there are better things that someone could spend $50 - $300 on.

[S13Coupe]

Well there's not many things you can do for $100 that shows any noticeable differences anyway, unless you buy all used parts from a good friend. It might not be a huge improvement, but it doesn't seem like too much of a risk to have one sent to that Maxbore place, and see what it does. I'm considering it if I can find a cheap extra one so I don't have any down time.

If I end up doing it, I will probly spring for a before/after dyno, and I'd be posting it up. Don't know what it would do for me. Stock motor, with Intake, Full exhaust, UR pulley, Flywheel. Seems like some bigger cams would make it more beneficial so that you could actually get some of that extra air in the cylinder.

[Rod]

Thank you all for the info. I was able to find a junk yard willing to sell the Q45 TB and a Z32 MAF for 120 bucks. I will pick those up and add a SAFCII and try to tune it on the dyno. I will keep you guys posted on the results.

Does anyone know of any dificulty of bolting on the Q45 TB on to the KADE'S Manifold? -just so I know what to expect when trying this.... :o)

Once again, thank you very much for the direction you guys provided!

- Rod

[Bigvinnie]

is it jsut me or is a 70m tb overkill for a motor pushing under say... 400rwhp?

ITB's are independent at upto 43mm a RUNNER, that means per piston!Total in VOLUME 172mm of atmospheric consumption, compared to a plenum based TB using 70mm to consume air.........The only purpose of using small TB's (60mm) on plenums is to create a vacuum and make swirl effect to atomize air/fuel (works best in all weather conditions). Maybe a little bit to do with scavaging the intake charge, but that is probably about it when it deals with usign a plenum. But the fact is, the engine will still cram more air per stroke with a larger TB.If you can run a 3" exhaust on the rear of your engine, what is to say that you can't run a 3" TB???It's like the oximoron that doesn't like an equal balance from both ends of the engine.....


Modified by Bigvinnie at 9:53 PM 1/24/2006

[Bigvinnie]

and NO it didnt give horsepower but it did make throttle response very very snappy and quick.

What makes an engine snappy and quick????????HP does. If throttle responce has increased the engines potential to respond and accelerate faster, HP has just been achieved.Bolt ons normally shifts HP and torque variables in the power band that is what there main purpose is. It is to manipulate the power achieved by the engine. It is also a method of fine tunning the engine to the conditions that you desire for it's enviornment.So if you are saying that the engine is snappy and much more responsive HP numbers were achieved in the low end. Power would also probably be provided in the high end since it would make an NA engine easier to obtain O2 from the atmosphere, since the diameter has increased, more air volume has increased, but not it's density.......Sorry about the double post........