Turbo KA24DE or SR20DET swap?

[JonCarson]

If you had about $4000 bucks to burn , which would rather do--Turbo charge your KA24DE engine or Transplant an SR20DET from Japan?

Both are going to require some extensive tuning and work to get them running right, both are going to make your 240SX illegal on the street, and both are going to have you smoking GS-Rs, Civic SIs, Eclipse GS-Ts, etc.

Some of you have already done one or the other. Do you wish you had taken the other path to force injected fun?

['97 S14 SE Turbo]

Well, sound's like I'm a perfect candidate for answering this question.

With only $4000 to burn, don't even think about getting a quality turbocharged SR20DET install or getting a KA24DE turbocharged correctly.

I have a mental amount on the money that I've spent on my car to get it to today. That's way too much money for any sane individual to spend.

At first, looking at prices for a used SR20DET or KA24DE's turbo kit, it may seem like getting the kit is enough. Well, not exactly. There is always the small and little things that quickly add up. A boost gauge here, EGT there, Turbo timer, exhaust, tire, brakes, suspension, chassis, etc... (No one in their right mind would want a turboed S13/S14 while still using the wimpy brakes.)

A straight forward swap in of a used SR20DET without checking it's health or a rebuild/refreshing is asking for a world of financial hurt. Anyone who denies this is day dreaming. The cost of parts and finding the knowledgeable people to do the work correctly and properly is tough and cost money.

Yeah, it's tempting. It may seem glamorious and stuff to have a turbocharged car, but beware of the increased operating cost and maintenance cost/time.

I did mine out of my engineering curiosity and my need for speed for road racing.

In hindsight, I should've gotten a slightly used M3 coupe for the amount of money that I've spent on my car and various parts.

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by carsonjon:
If you had about $4000 bucks to burn , which would rather do--Turbo charge your KA24DE engine or Transplant an SR20DET from Japan?

Both are going to require some extensive tuning and work to get them running right, both are going to make your 240SX illegal on the street, and both are going to have you smoking GS-Rs, Civic SIs, Eclipse GS-Ts, etc.

Some of you have already done one or the other. Do you wish you had taken the other path to force injected fun?<HR></BLOCKQUOTE>

[JonCarson]

Ok. I can appreciate that, but this is a dream thing.

All things being equal, which would you rather do?


<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by '97 S14 SE Turbo:
"With only $4000 to burn, don't even think about getting a quality turbocharged SR20DET install or getting a KA24DE turbocharged correctly.

I have a mental amount on the money that I've spent on my car to get it to today. That's way too much money for any sane individual to spend."
<HR></BLOCKQUOTE>

['97 S14 SE Turbo]

Well, with only $4k to burn, I would buy some good high performing stocks. To do it right would cost $6k to make things perfect.

To me the best method is to turbocharge the KA24DE motor. The reason behind this is many. People are going to say, hey, that's a truck motor. Well, yes it was. It was based on a truck motor. What does that mean? That means to me that this motor/block will be very, very tough!! Many powerful engines in the Big Three are truck derived. Even the MKIII Supra's single turbo motor is truck based.

Well here are some features of the KA24DE most turbo motors will wish they have. Piston oil squirter/cooler. Yup, this wimpy truck motor have piston oil cooler that the high end turbo motors like the SR20 have. This feature is important for keeping the piston temperature down.

Another impressive feature is the size of the crank shaft girdle. Most engines, even the big blocks uses bearing caps. The KA24DE have a solid single piece girdle in place of the individual bearing caps. Heck, even the RB series engines uses girdle. For the heavily modified RBs goes to the solid girdle. The new S2000's engine also have a solid girdle. The other hot Honda engines don't have one. Spoon sports have a custom engine block with the solid girdle for their versions of the Civic Type R or Integra for the added strength.

So, let's recap, the KA24DE have turbocharged engine's piston oil cooler plus a super strong cast iron girdle.

Besides the weak pistons in the KA24DE from '91-'94, and the stronger pistons in the '95-'98 KA24DE, there's nothing else to be changed on the engine. Just put in some lower compression forged or cast Eutatic piston and use the '98 Altima's KA24 piston rings (something JWT found out that is stronger than aftermarket.)

Advantage over the SR20DET is the cast iron block and it's inherently stronger strength plus the bottom end's girdle. It also have 400cc displacement advantage over the SR20DET. The added displacement and the longer intake manifold will give the KA24DE a much different character than the high reving SR20. THe KA24DE(T) will have torque up the wazoo, more than anyone could use safely. The SR's block needs modification if power level gets near 350hp. KA's block doesn't!!

I've ridden in both SR20DET powered S14 and KA24DET powered S13/S14. Guess which one impressed me more? The KA24DET!!!

Let's say the torque wins me over. No traction in 1st, 2nd, and part of 3rd gear!!! The accelaration was brutle. The SR20DET S14 on the other hand was smooth and unexciting. You can get more horse power out of a lightly boosed stock internal KA24DE than a stock boosted SR20DET.

The other thing that won me over is the parts availablity for the KA in case I blew one. You can buy a used shortblock for $400. Pretty cheap.


<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by carsonjon:
Ok. I can appreciate that, but this is a dream thing.

All things being equal, which would you rather do?


<HR></BLOCKQUOTE>



[This message has been edited by '97 S14 SE Turbo (edited 02-22-2000).]

[Meeks32]

I was thinking about putting a turbo in mine, but is there anyway you can make the KA24DE more balanced & not so rough? Maybe I was spoiled when I had to drive my sisters Prelude Vtec before I got mine, that thing was smooth.

[**DONOTDELETE**]

Like 97se Turbo I too got the bug shortly after purchasing my 98 240SX LE. I have installed an F-Max kit, forged pistons w/ total seal rings and a lot more. To date I have spent about $15,000.00 + but I have a car that will trim most anything on the road and I am SCCA competitive in SM. I agree after going through my new engine (16,000 miles) it is really built. I am a certified FAA technician (A&P) and I really appreciate the way Nissan built this engine. Anyone interested see my home page @ http://www.importcargarage.com I was able to attend NOPI 99 and took first place in Asian Sport Compact 240SX Mild. Yes, the upgrade it is worth it in my opinion.

['97 S14 SE Turbo]

The '95-'98 engines are smoother and more balanced than the '91-'94 KA engines. One thing to keep in mind is that Inline 4s are inherently unstable, so what roughtness?

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by Meeks32:
I was thinking about putting a turbo in mine, but is there anyway you can make the KA24DE more balanced & not so rough? Maybe I was spoiled when I had to drive my sisters Prelude Vtec before I got mine, that thing was smooth. <HR></BLOCKQUOTE>

[**DONOTDELETE**]

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by '97 S14 SE Turbo:
The '95-'98 engines are smoother and more balanced than the '91-'94 KA engines. One thing to keep in mind is that Inline 4s are inherently unstable, so what roughtness?

<HR></BLOCKQUOTE>

I think the 97+ KA24DEs in the Altima actually had microfinished pistons and crankshafts. I don't know if Nissan did that for the KA24DE in the S14 240SX.

['97 S14 SE Turbo]

Just got back from the track for the first time w/ the Turbo inplace. Trap speed of 103.26mph @ 14.23 sec and 103.1mph @ 14.10 sec.

For the trap speed seen, the ET should be in the 13s but due to my less than stallar job drag launching my S14 with it's road race suspension setup.

Anyway, at 11psi of boost, the KA24DE will produce about ~290hp with stock internal running F-Max's turbokit w/ 50lb/hr injectors, '93 Mustang Cobra MAFS, JWT ecu plus A'PEXi GT Spec Exhaust.

[**DONOTDELETE**]

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by '97 S14 SE Turbo:
Just got back from the track for the first time w/ the Turbo inplace. Trap speed of 103.26mph @ 14.23 sec and 103.1mph @ 14.10 sec.

For the trap speed seen, the ET should be in the 13s but due to my less than stallar job drag launching my S14 with it's road race suspension setup.

Anyway, at 11psi of boost, the KA24DE will produce about ~290hp with stock internal running F-Max's turbokit w/ 50lb/hr injectors, '93 Mustang Cobra MAFS, JWT ecu plus A'PEXi GT Spec Exhaust.

<HR></BLOCKQUOTE>

Damn, that's impressive 103 mph at 1/4 mile. I thought my friend's Maxima's 92 mph 1/4 mile was good.

What's your 0-60?

['97 S14 SE Turbo]

Probably in the 4's or 5's depending on how hard I'm launching.

All I know is that I can outrun the C4 Corvette (LT1s) by about 3 car lengths in the quarter.

<BLOCKQUOTE><font size="1" face="Verdana, Arial[/img]quote:</font><HR>Originally posted by htmlcoder:
Damn, that's impressive 103 mph at 1/4 mile. I thought my friend's Maxima's 92 mph 1/4 mile was good.

What's your 0-60?<HR></BLOCKQUOTE>