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View Full Version : Another Engine Comparison Post


DrDubbleB
03-21-2002, 10:21 PM
Ok, I just wanted to lay it all out, and compare two of the biggest options for us 240 enthusiasts. The KA24DE-T, and the SR20DET (in no particular order).

First up, let's go with the KA-T (this will go in the order listed above).
Advantages:

Torque. It has loads of torque. You can attribute this to the extra .4 litres that it has over the next closest engine's displacement. Torque is a good thing, and it's fun! <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/biggrin.gif" border="0" valign="absmiddle" alt=':D'>

The previously mentioned .4 litres. It can help to give you extra power, and some people believe in the "there's no replacement for displacement" saying. Displacement is a good thing.

The iron block. It's iron, strong, and durable stuff, practically bullet proof.

Linear power band. The KA can deliver the power very equally at all RPM's. This allows a good launch, and a good finish, and also good pickup no matter where you are (of course, not if you are trying to speed off in fifth gear at 15 miles an hour, but you get the point).

Disadvantages:

It's not designed for a turbo. Never has the KA come straight out of the factory turboed. This could possibly lead to a shorter engine life under the added stress of a turbo. Of course, the higher the HP, the lower the life-span will be, w/o proper upgrades.

Revs. The KA is not a rev happy engine. It has a relatively low redline compared to the SR.

Cam design. The cams are not designed for turbo applications, and therefore are not performing optimally.

The compression ratio. 9.5:1 compression is tetering on the high-side for turbo applications. Ideally, you want it somewhere between 7.5 (low) to 9.5 (high), so it's on the very edge. Remember, if you lower the compression, you can raise the boost.

Second, the SR.
Advantages:

The SR's aluminum block. It is slightly lighter than the KA due to the material used. To all those concerned with every pound that your car has.

It is designed for turbo use. It came out of the factory turboed, and in NA form. It's cams, and various other parts of the engine, are made for turbo. The engine's life is not shortened because of a turbo, however, under high boost, or high HP situations, it could be.

Higher revving. The SR's redline is higher than the KA, allowing rev happy people to go about their fun. A higher redline usually means a larger powerband, but not always (in this case it does though).

The compression ratio. 8.5:1 is right in the middle of the optimal compression for a turbo charged engine. Keep in mind it's not necessarily the best compression just because it's in the middle.

Disadvantages:

The power band. The SR's powerband tends to be more on the high side of things, and less linear than the KA. This allows for a lot of pull at higher RPMs, but less at take off.

Displacement. At 2.0 litres it has a disadvantage in some people's minds. Some people believe there's less potential, however technology improvements to minimize that.

Stock HP. S13's 205, S14's 220. There's no real contender with a turboed KA until you get to the expensive S15's which have 250.

This comes straight from driftfreaq..."well I will add to the SR's disadvantages the rockers you can spin them at high revs. You also need to replace them every 60-70K that is expensive and a big disadvantage in my book." &nbsp;I thought that should get mentioned, as it did slip my mind, and is a disadvantage (even though it has nothing to do with performance...just reliability). &nbsp;I would like to add that this is not normally a one time thing, but it comes after quite a bit of abuse.

Anyways, I did not put some things because this was getting long enough. That's what I came up with, feel free to add/correct as you please, I do not want to misinform, and I would like to get more knowledgable as well.

I did not mention the CA because honestly when I looked at it, I was just not impressed enough. Anyone that cares to add that, do so, I would like to see the advantages and disadvantages.

Most of the disadvantages listed are curable as you can see, so that is why the argument and bickering as to which is better will not end.

Bomix
03-21-2002, 10:35 PM
Interesting comparsions. &nbsp; <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/whatsthat.gif" border="0" valign="absmiddle" alt=':whatthe:'> I actually enjoyed reading all that.. &nbsp; <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/notify.gif" border="0" valign="absmiddle" alt=':notify:'>

drift freaq
03-21-2002, 10:53 PM
well I will add to the SR's disadvantages the rockers you can spin them at high revs. You also need to replace them every 60-70K that is expensive and a big disadvantage in my book.

oh yeah you forgot to mention that KA pistons have oil squirters that is important for a Turbo engine.
Also your statement about the KA never being designed for Turbo while true is not a disadvantage because basically the KA bottome end is strong enough for a Turbo stock.
also you fail to realize that a KA+t done right can be just as reliable as s SR20det.
Oh and by the way I did post on this but we have been down this road way to many times recently why don't you just read the archives and draw your conclusions there?

Can we say lets beat the dead horse once again? <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=':p'> &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/sly.gif" border="0" valign="absmiddle" alt=':sly:'> &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/hehe.gif" border="0" valign="absmiddle" alt=':hehe:'> &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/hehe.gif" border="0" valign="absmiddle" alt=':hehe:'> &nbsp;<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/hehe.gif" border="0" valign="absmiddle" alt=':hehe:'> &nbsp;DRbubbleB hahaha

DrDubbleB
03-21-2002, 11:01 PM
Mannnn...you were supposed to give your unbiased answer. Ahhh well...shoulda known that never would have happened. Point is, yes if done right (which I mentioned) the KA can be reliable, but still was never meant to be turboed, so there will still be a shortened engine life. So it is a disadvantage not being designed for it, which IMO is why the SR is able to contend or surpass the engine with less displacement.

I forgot about the rocker arms, sorry, I knew that too, just slipped my mind. I will go back into the main post and fix that so that anyone who reads it can see it right off the bat. But you do have to severly over-rev (*cough* bad driver *cough*) the engine in order to spin them.
Also can't you get replacement rocker arms to fix that? (could be wrong, probably am).

I was trying to give the people an unbiased comparison dpr0, geeeze...why'd you have to ruin that! <img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/tounge.gif" border="0" valign="absmiddle" alt=':p'>

AceInHole
03-21-2002, 11:52 PM
Some pointless questions to scratch your heads to:

A: What makes an engine any more designed to be turbo'ed than an engine that's "never meant to be turbo'ed". &nbsp;If the KA was really "never meant to be turbo'ed", wouldn't there be a big warning tag on it that says "don't turbo this engine"?? &nbsp;And wouldn't people who have turbo'ed the KA experience engine failure noticeably earlier than SR's instead of the other way around?? (Uhh, yes, I did just imply what I implied there, so don't even ask, just flame if you want). &nbsp;

B: I love how some enthusiasts claim the rocker arms falling off at 8k rpm is a designed safety measure in the SR.

C: SR advantage (the biggest one in my book) is that it's associated tranny is noticeably stronger than the KA's. &nbsp;(first clue is the larger flywheel surface).

Just a few comments on the "dead horse". &nbsp;Someone needs to fix the search engine.

DrDubbleB
03-22-2002, 12:11 AM
Listen. This post was not intended to get everyone into a pissing match. This post was not intended to make comments like "B: I love how some enthusiasts claim the rocker arms falling off at 8k rpm is a designed safety measure in the SR." I did not say that, so why bring it up? This post was not intended for people to express their opinions on what motors are better.

This post was intended to compare the two motors and pool their resources to gather a "FAQ" if you will about them. This post was intended so that other people could see an unbiased "review" of the strengths and weaknesses of each motor and then come up with their own opinions, so that they could make decisions for their future if they decided either route.

Now, if this post gets out of hand, and people start doing what the post was not intended for, I hope this gets shut down. As for the comment on how SRs die before KAs, I'm not going to argue because that's not what this post is for.

CHARLIE2020
11-23-2005, 10:10 AM
For you guys that had rocker arm flying off issues on the SR, you know that Nissan revised this part and now has a deeper bowl on the rocker arm that makes it less prone to falling off and there are 3 different type of HLVA's and one of them performs alot better than the rest and is less prone to valve float, the newer style rocker arms shoudl be on all 98 and above DET's and the better HVLA's i believe come from the FWD roller rocker sr20 but im not sure I have to reverify that again.

TheSnail
11-23-2005, 10:17 AM
The S15 was still in production the last time someone posted in this thread.

North240
11-23-2005, 11:16 AM
I'd like to thank you for this nice trip down memory lane..........

sLiDewAys
11-23-2005, 11:23 AM
Leave the Aluminum for Cans and Garbage cans. Sr's blow too easily in my perspective. kat is GODLY when its built right and CA owns, thats unles you have an rb which is like mr. ca's big grampa.

SR SR SR SR, im gona go to japan and sabotage all the sr motors so u silly kids get ripped off nicly for thinkin ur car resembles one from initial d.

i have some se friend putting pretty decent power out of their motors. thats good to hear and see but we know that high hp engines are high maintenance and NOOB's simply dont care enough yet to take it serriously.

so. i say build your suspension and drop in a dodge viper motor if u want torque. otherwise its kat or cat only for me.

Gnnr
11-23-2005, 11:46 AM
^^^Dude...its an old thread.

S14DB
11-23-2005, 11:49 AM
For you guys that had rocker arm flying off issues on the SR, you know that Nissan revised this part and now has a deeper bowl on the rocker arm that makes it less prone to falling off and there are 3 different type of HLVA's and one of them performs alot better than the rest and is less prone to valve float, the newer style rocker arms shoudl be on all 98 and above DET's and the better HVLA's i believe come from the FWD roller rocker sr20 but im not sure I have to reverify that again.
Please don't bump 3yr old threads... K thnx bye! :squint: