Tell me what long run potential does the KA realy have.

[240sxRAOR]

I have 92 vert with a ka24de and 5-speed. I like the SR20 and all but I just love my KA and don't see anything wrong with it. I want to know how far can you go with the ka24de internals? Can you make the KA a high rev engine thats still reliable? I have a good friend who tells me that is the real big difference between KA an SR, its where they get thier power and he says your much better of with an SR because the SR is more reliable and has much better High RPM power and was made for the track. I guess what I'm saying is can you fine tune the ka24de so that you can rev high and run decent boost and make it atleast on the level with SR20's. I'm not asking which is better, I'm asking what can you realy get out of the KA24DE since it is a truck engine and can you turn it into a good track engine. I'm just tired of getting "That engine's hopeless, get an SR." It just makes me want to prove them wrong. Were I live my car is underapreciated enough or maybe people are just jealous of the 240sx.

[DjPantsSpecR]

Neither engines were built for the track. If i were going to say any of the four bangers nissan has built should even consider going to the track i would say its the CA. For a high revving motor the SR is still pretty cushy. You can get it to rev, but not without a lot of work.

Some of our KAs rev to 7200, most of them dont. Some SRs rev to 7500, some dont. These arent even high revs really, but both of these motors fall off in these revs.

Neither are actually built for high RPM track use. Thats just SR20 fan boy talk right there. Most sr20 turbos (specifically the t25s) run out of breath long before any high revs. Its cams and intake manifold also add to this occurance.

The KA is a dog in the upper Rs on almost every N/A dyno ive ever seen. So many things go "wrong" with the KA. The cams arent exactly anywhere near where you want them to be for high revs, and the intake manifold has something like 22 inches of runner. The plenum is much too small, and its stroke is ridiculous.

But your question isnt about the motors ability to make power at revs, its simply if it can....

A KA head is generally agreed to be good til 8k. Ive never seen it happen, or participated in an 8k KA build, so it may or may not be true. However, its solid lifter design (on DEs) allows for greater revs right out of the box. Upgrades valve springs might be all the insurance you need to make it to 8k. I have no idea how far you could, or would want to go after that. Its not an rsx.....

Now the bottom end of the KA is amess for any high rpm usage. The stroke is ridiculous. The piston accelerations at those kind of revs would be devestating. You might be able to get to 8k if you had new bearings within a certain tolerance, some ARP fasteners, and rods. Once again, i havent built it, but im just trying to point you in the right direction. ideally you would want all that, and the probably pistons too, with a fully counterweighted crankshaft, and oil scrapers and windage tray. That not even mentioning balancing and blueprinting for those kinds of revs.

i would do the exact same on an SR. its not ready to go that high yet. With theamount of money you waste on doing something to a KA, you would spend the same doing it to an SR. And most people overlook that you can reach SR power levels with just bolt ons and a healthy KA.

[240sxRAOR]

Thanks alot for the info, Umm what I meant by high rev is getting power in the higher revs like 4-7 instead of the lower revs. What I realy want to do is to have a balanced car that is tough and will last a long time. I'd like to supercharge my KA with a 7-10 pound boost (which most disagree with but I like it better for good reasons.) put in better cams for it so it has better 4-7 rpm power, aftermarket pistons , port polish, and other engine clean up and tunning. I did want to know if the KA had higher potential. Now I just like to know how good would a KA be for regular street use. I want to drive this car every day and just want to make 250rwhp and still have it dependable. I'd like to take it to a track every once in a while but not for competition. I realy just want to know can the KA be dependable at 250rwhp. I just want to be able to show up all those people who say its useless and say a civic would tear you apart. One last thing, does it realy matter all that much if a car revs high, do you really need to rev high to drift and keep you tires spinning, honestly I don't think so, I think 4-7k would be fine but I could be wrong. Thanks again.

[DjPantsSpecR]

Okay, i feel ya.

You can make power in high revs. There are a few things holding you back though.... i shoot for 4-7k so i know what you're saying.

Ive said it a million times, and ive even built my own, but the KA intake manifold is ridiculous. Its helmholtz resonance allows for greater power in low RPMS, but it falls on its face up top. Just adding an intake manifold will reshape this power band. You can shift your power band up by cutting the runners and having a plenum welded on. search "30 dollar intake manifold"

High compression will get you power everywhere. plus if you're N/A and youre on low comp youre not even competeing....

cams and GEARS especially gears. Some people claim that even stock cams with gears can make an additional 15 horse. this is what ive read about someone reading about 510 guys with DEs. I'm going to have a set of gears drilled to see what potential problems arise there, im sure i will need ot get them heat treated.

header and exhaust also wil help you shift the power band to the higher rpms. Half the people say hotshot and the other half say DC, and the broke people all grab OBX. I will grab anything i can get for about a bill....

There are a million small free mods that can help you more the power badn or just plain few up fractions of ponies, but those you'll learn....

i know im missing something i wanted to say, but remember this one fact: If you spent all the money on all motor KA parts that you would spend on an SR front clip, you should have more than the 180whp that the SR does. And thats jsut peak power, there is no doubt you'll have more low end grunt. Besides the pistons, you can basically get there with bolt-ons. Or save the pistons, and grab one of thomas knights supercharger kits on ebay.

250rwhp is unreasonable on a streetable KA 250BHP is more reasonable, but expensive

[240sxRAOR]

Thanks alot dude, just one more thing whats Bhp?

[DjPantsSpecR]

crank horsepower. Horsepower generated at the crank. Before its wasted by drivetrain.

Im gonna make a huge assumption here, but generally we assume about a 20% driveline loss. So while your motor might make 155bhp, it can only put 133 to the ground. THats not exactly 20%, but its a realistic wheel horsepower measurement for a healthy stock KA.

[Bigvinnie]

UM if you want a engine that was built for the track get an FJ20e it came in all the oldschool skylines. Engines have mad potential if you can get your hands on one. Many people at the dimequarterly normally have them.Devious KA happens to selllot of his stuff there as well.http://www.fj20.com/http://www.dimequarterly.com