my comments on 248/240 s13 cam swap

Information on the naturally-aspirated KA24E and KA24DE engines.
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DjPantsSpecR
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Postby DjPantsSpecR » Sun Oct 08, 2006 5:56 pm

your cams in that piciture are fine so long as youre at TDC. what cams are those, 232/232s?

i'm having a hard time figuring out what youre asking me. youre installing 240/248 cams in now?

if so then you just swap the cams and leave the cam gears exactly the same.

if that not what youre doing, let me know.


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Re: (DjPantsSpecR)

Postby 2.240s » Sun Oct 22, 2006 3:06 pm

Hey i know this is a old thread, thought i would bring it to life. I have a s14 95 ka hotshotheader , intake, 2.5 exhaust. going to do the 13 cam swap , after reading now im not sure what is the best option for me . I dont want to lose low end because most of my driving is canyon carving and street. so 248/232 is what you suggest not 248/248. ???

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Postby DjPantsSpecR » Sun Oct 22, 2006 4:03 pm

this definately isnt an old thread, this is a very useful thread. As soon as i split up everything that is useful in here from everything else, this thread along with my DIY adjustable cam gears are going to be stickied at the top of the KA section. should mkae everyones life easier who is looking at swaping cams.

i really dont even know what to think anymore, my cam options are so wide open right now that i havent tried half the stuff i want to.

but what im currently using is 248/248 and ive advanced the 248intake cam by 5degrees to get it to 3.2 degrees of actual advance. So if what we've researched is true, then this is actually an advance of 2.2 degrees. so 248(+2.2). on the exhaust side i ve retarded my cam 2.5 degrees, so i got 248(+2.2)/248(-2.5).

now im going for a bunch of top end, and im getting ready for my new intake manifold and this winters high compresion swap.

Now, for your app (and the hotshot+2.5, and since youre cali you definately have a cat) i used to offer 240/232. I have this combo in my auto car and it really is a good combo, and you already know that your intake and exhaust events are factory, so you're not worrying about the 248.

However, since i figured out how to redrill gears in about 20 minutes, ive been doing it more and offering up new advice. For your app i wuld suggest 248/232. but i would put the 248 in using the 4 teeth CCW method, and then advance it +2.5 to bring it to almost its factory postion of .7 degrees after tdc.

then once, youve done that, drive it for three days and see how you like it (dont forget to reset the ecu, or it will need to re-learn for a while, but it works too) then redrill your exhaust gear for 2.5 degrees of retard. see if you really think youre losing some midrange, i bet you wouldnt even notice as your top end should pull a little better.

then once thats done, redrill the intake again for 5 degrees of advance, then drive that for three days, and compare.

Now what ive just figured out while i was typing this to you has something to do with the actual durations associated with these cams. im not sur ehow much i believe what i hear, but 248s are an actual of 241, 240s are an actual of 227. i forget what 232 was but i wanna say 212, although im sure thats not correct.

the the eight degree difference between the two cams is actually a much larger difference, with the 248 being closer to its advertised duration. Now what i was thinking has soenthing to do with the original content of this thread.

now i could actually try 248/240 again. Advance the intake 248 by 5 degrees of advance, then install the exhaust 240. technically the 240 cam should be a little retarded (.7 degrees) and you could even retard it further to get it to make power in different levels. i would be interested to see what owuld happen now, but i need to rethink the whole exhaust cam thing....

so in re-answering your question: i really can only offer suggestions, stuff that i really, really like. you gotta keep in mind that i did all my intitial cam comparos with an entirely stock automatic, jsut to keep things consistent. now when you start with mods your cam selection should compliment this.

but 248/232 is (IMO) never better than 240/232. if you actually redrill the gears to work i would definately prefer 248/232 over 240/232, however.

but with the large actual duration compared to 240, i really like 248/248. The midrange was better with 248(+5)/248, and it might be even better with 248(+2.5)/248.

248(+5)/248(-2.5): My car has a big dip in power from 2k-3k, but the top end from 5500-7000 is better than ever. its still incredibly torquey, as you are probably only losing a few ft/lbs, so i dont notice/miss it. You never spend time there anyways, and its only used for cruising.

and dont forget you can always make midrange or low end by retarding the intake (or leaving a 248 installed without gear) cam, and to less of an extent advancing the exhasut cam. top end can be found by advancing the intake and retarding the exhaust.

and btw, i thought my car idled like a small block now.... until i heard Ivan is using 10 degrees of advance on the intake side... i dont know his exhaust cam timing, but obviously Ivan knows where hes found power. and this is with big V3 cams.

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Re: (DjPantsSpecR)

Postby 2.240s » Sun Oct 22, 2006 8:06 pm

Right on, thanxs for the info. I might just stick with the 240/232 swap and go from there. Thanks again. so thats 240 s13 intake cam/232 s14 exhaust cam.?
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Postby DjPantsSpecR » Mon Oct 23, 2006 3:56 am

yep, enjoy

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Postby ~4N~ » Tue Oct 24, 2006 11:57 am

So, to acheive 248/232 on a '93 S13 KA, I have to move the exhaust cam over to the intake side, and then install an S14 KA cam in place of the exhaust cam, correct?

Thanks for the info.

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Postby struckinc » Tue Oct 24, 2006 12:15 pm

yes. using the 4 tooth method on the intake...or making your own gear...or you can use the 92-95 altima exhaust cam and after the adjustment you timing will only be off about .5 deg...that is the setup i am running

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Postby ~4N~ » Tue Oct 24, 2006 12:19 pm

Thanks.By the way, is there any way to tell if it's an S14 cam? I should be getting one soon from a friend, and it'd be nice to make sure it's a cam from an S14.

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Postby struckinc » Tue Oct 24, 2006 12:31 pm

the s14 is opposite from the s13 as far as colors go..most s14's have a green stripe on the exhaust and a orange stripe on the intake..you can look at the alignment pin to tell. if the alignment pin is in line with the first lobe and the stripe is orange it is a s14 intake..aligned and has a green stripe s13 intake...if the first lobe is offset clockwise about 4 teeth from the pin and has a green stripe it is s14 exhaust...same as above but orange stripe s13 exhaust

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Postby ~4N~ » Tue Oct 24, 2006 12:33 pm

That's very helpful, thanks.

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Re: (struckinc)

Postby Bigvinnie » Tue Oct 24, 2006 12:35 pm

struckinc wrote:yes. using the 4 tooth method on the intake...or making your own gear...or you can use the 92-95 altima exhaust cam and after the adjustment you timing will only be off about .5 deg...that is the setup i am running
I believe that it would be a .5 degree advancement. IMO still not good enough for high rev and HP. The majority of guys that are making power with even stock s13 KA's retard between 3~5degress from stock duration on INT to increase power in the higher RPM (using the stock 240/248). It follows alot of the same principles like honda Vtech to bring overlap closer and lower within the first stroke to promote healthier power at higher RPM. A .5 degree advancement is still not as good as stock and I have yet to see a dyno that promotes a larger amount of HP at that degree.Granted the engine will provide a healthy torque range, but HP will still be something that needs to be seen.

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Postby DjPantsSpecR » Tue Oct 24, 2006 5:13 pm

wait, vinnie, really?

I think what you wrote is confusing me, you put that guys are retarding their intake cams to make top end by retarding them. this is kinda counter-intuitive to everything ive learned.

are you sure you meant 3-5 degrees of retard?

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Postby struckinc » Wed Oct 25, 2006 2:23 am

i am confused also. could you explain the reasoning for that? not to question you or doubt you but i dont understand what you mean

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Re: (DjPantsSpecR)

Postby Bigvinnie » Wed Oct 25, 2006 9:47 am

DjPantsSpecR wrote:wait, vinnie, really?

I think what you wrote is confusing me, you put that guys are retarding their intake cams to make top end by retarding them. this is kinda counter-intuitive to everything ive learned.

are you sure you meant 3-5 degrees of retard?
I'm positive. I saw a dyno a few months back with an s13KA24de 92 stock 240/248 cam setup using a jim wolf technology cam gear on INT. I am not quite sure how far the cam was retarded but it was retarded (assuming if JWT it was 7 degrees retarded maybe?). Fuel mixture at low throttle was also leaned out at partuicular parts of the rpm range and a wide band O2 was used. Pretty much stock internals with intake, advanced timing, and header was pushing roughly 180HP at the wheels and KNOCK settings didn't raise more than a point from what the SAFC was regestering on the monitor.If you look at the 248/248 nismo cams the reason why infact it doesn't make power is because INT is advanced further than what stock is. But if you look at 232/232 they make good power, so now the realative answer to that is because of the actual cam placement of 248 onto INT.I also do realize the larger the duration the cam onto INT the more retarded the cam will need to be in order for the engine to run or IDLE properlly. Retarding the cam will only allow the valve to open later into stroke one creating a stronger vacuum. There is no direct equation or calculation for cam placement other than what I do know nissan engines with a simalar rod/stroke ratio tuners have normally chosen to back off cams.As far as best mean torque the engine will do fine achieving a high torque band with a cam slightly advanced, but it shows small returns for HP output.Years ago I use to own a z24I, it came with an adjustable timing gear that would advance or retard +/- 3degrees. I did notice that low end torque drops a tad retarding the cam, but high end acceleration was much better for the most part. It felt more like an Honda engine accelerating as if it wanted to keep reving faster.If I also remember correctly there was this 19 year old named Tre that was at Zilvia, and in the Nissan Pacific forums. I found his method of tuning to be somewhat awkward and I dogged the kid pretty bad in the forums. He happen to retard the exhaust and his intake using the stock cams and JWT cam gears. I was knocking on him for advancing the distributor fully. I was ragging on him for raising the EGT and splitting the timing gap too far also disturbing his idle, and since the engines are also prone to knock he was running piss loads of fuel. He claimed that knock wasn't so bad either. In the end of the arguement he showed me his time slip for his stock block, damn youngster ran a 14.9sec 1/4mile or what is the equivlant to 205 hp at the crank. I still don't recomend his cam placement or timing confuiguration though.


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Postby InsanityInc » Wed Oct 25, 2006 11:15 am

Retarding the intake cam makes more high end power because it extends the closing of the intake valve further past BDC, which allows for air with more inertia (at higher RPM, your intake air has more inertia) to create a supercharging effect in the cylinder. It's the same reason why more duration on the intake is desirable. But, don't retard it too far or you'll screw your intake opening up.

Advancing the intake cam is usually doubly bad because you increase overlap and move intake closing closer to BDC, which will make the car usually run like crap overall.

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Re: (InsanityInc)

Postby Bigvinnie » Wed Oct 25, 2006 12:42 pm

InsanityInc wrote:Retarding the intake cam makes more high end power because it extends the closing of the intake valve further past BDC, which allows for air with more inertia (at higher RPM, your intake air has more inertia) to create a supercharging effect in the cylinder. It's the same reason why more duration on the intake is desirable. But, don't retard it too far or you'll screw your intake opening up.

Advancing the intake cam is usually doubly bad because you increase overlap and move intake closing closer to BDC, which will make the car usually run like crap overall.
BINGO!The inertia that is created increases atomization! The only reason why the KA cams are set to there position is just for smog and fuel economy, but nobody to date has ever cared to clarify the missing 15+ HP you can get from stock cams properlly setting them within the safety margin of 3~5%degrees retarded from stock. In other words when I try to express advanced cam placement as best mean torque you can see it on any KA dyno graph where as the KA usually produces more torque than HP (well atleast bone stock), I would say that Nissan has already determined that cam placement is already to far advanced, but was set for proper fuel economy.Advancing the cam past the recomended stock spec will also decrease fuel economy since in the long run actual engine VE's and AE's drop from stock spec and too much overlap occurs when the engine is producing power for load.In many cases Nissan now uses CVT to position cams, just as Honda uses I-vtec. Vtec when it was first developed only allowed for a cam to be retarded in order to increase power at higher RPM. Now I-vtec or Nissan's CVT can now adjust cams either to advance or retard depending on driver habits to conserve fuel.So when people ask me if the HOT CAM setups are great I always say no. Just because they don't make the kind of power that they could be making if set to the right degree that the engine likes. Again people also need to remember that there is no formula or calculation for setting a cam to make the most power withing the first stroke, so it sucks when you have to hit the dynop numerous times to reset a cam position. One of the reasons why like my stockers (240/248).

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Postby DjPantsSpecR » Wed Oct 25, 2006 2:29 pm

okay, well youg ot me all excited, so as soon as i read this i ran home and redrilled a gear for 5 degrees of retard. this is on a 248 intake cam, so its already 1.8 degrees before tdc, so it should sit around 6.7 retarded. this is paired with an exhaust (248) that i left 2.5 degrees retarded.

the car idled fine, and it sounded entirely different. however when i went to drive it, there was clearly something wrong. there was no response anywhere and power was clearly very very weak. i didnt take it past 3k, because obviously there was a porblem.

so i set it back to stock. i guess if i were going to get this to work i would want 2.5 degrees of retard on the intake cam and probably 2.5 degrees of advance on the exhaust cam.

so clearly, this 7 degrees retarded idea doesnt work on a 248 intake. at least with minimal exhaust retard. i'll have to wait until another time to do all the cam math to see what exactly is happening, but clearly this isnt for 248/248 users.

im eager to try 240/248 set to stock with -5 adn -2.5 degrees of retard, however. you should try 248(+5)/248(-2.5) as a compareson as well, before you can say the "hot cam setups" are bogus.

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Re: (DjPantsSpecR)

Postby Bigvinnie » Wed Oct 25, 2006 4:56 pm

DjPantsSpecR wrote:im eager to try 240/248 set to stock with -5 adn -2.5 degrees of retard, however. you should try 248(+5)/248(-2.5) as a compareson as well, before you can say the "hot cam setups" are bogus.
Just to let you know the set up that is being used.240/248 cams onto s13 ka24de. INT is retarded 7degrees timing is advanced at the distributor 3 degrees.That was the set up that was used on the KA24de that was dynoed.That also happen to be TRE's set up with out the exception of fully advancing the distributor, which is what I highly disagree with (raised EGT higher exhaust levels it would need iridium plugs).Fuel curve also needs to be changed with an SAFC or ECU tune, fuel ratio between 12.7:1~13.4:1.

Now if you were to run this as a streetable set up it would only be 3 degrees retarded onto INT (at most, it should relatively be at 2 degrees retarded). No advancement or retarding of the exhaust cam. Some adjustments with an safc possibly to run a little more lean in Low and HI throttle.

As far as 248/248 that is a whole other can a worms and I would have no clue as to what position the cams would need to be set.

Edit: made an error as well Tre used an exhaust cam at 5 degrees retarded.
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Postby DjPantsSpecR » Wed Oct 25, 2006 6:01 pm

yeah i know, but thank you so very much for that cam info, i cant wait to try it. hopefully it doesnt snow anytime soon, or else im just going to do the cam swap to my winter 240.

either way, good findd, i could never find anything about cam timing before

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Re: (DjPantsSpecR)

Postby Bigvinnie » Wed Oct 25, 2006 7:20 pm

Just for future refrence here is what a dyno of the 248/248 looks like.The stock cams provided, make more power than what NISMO made as a 248/248 combo. The location of the dowel pin on the NISMO was revised for proper cam placement in stock position. As you can see the cam needs some serious retarding to make power. Maybe one day I might try the 248/248 but not until someone does more research and shows some dyno's...On another note since the duration of the cam is longer as well as a closer overlap, the cam would need to be retarded.Reason number one: larger duration closer to TDC can decrease CFM, since lift and duration has increased and isn't in proportion to overlap with EX.Reason number two: as the piston moves further to BDC there is more inertia creating a stronger vacuum that would increase CFM to handle the larger lift and duration cam. The dyno speaks for itself and advancing the 248 won't make any type of suitable power. Just my 2 cents.




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Re: (DjPantsSpecR)

Postby InsanityInc » Wed Oct 25, 2006 8:20 pm

DjPantsSpecR wrote:okay, well youg ot me all excited, so as soon as i read this i ran home and redrilled a gear for 5 degrees of retard. this is on a 248 intake cam, so its already 1.8 degrees before tdc, so it should sit around 6.7 retarded. this is paired with an exhaust (248) that i left 2.5 degrees retarded.

the car idled fine, and it sounded entirely different. however when i went to drive it, there was clearly something wrong. there was no response anywhere and power was clearly very very weak. i didnt take it past 3k, because obviously there was a porblem.

so i set it back to stock. i guess if i were going to get this to work i would want 2.5 degrees of retard on the intake cam and probably 2.5 degrees of advance on the exhaust cam.

so clearly, this 7 degrees retarded idea doesnt work on a 248 intake. at least with minimal exhaust retard. i'll have to wait until another time to do all the cam math to see what exactly is happening, but clearly this isnt for 248/248 users.

im eager to try 240/248 set to stock with -5 adn -2.5 degrees of retard, however. you should try 248(+5)/248(-2.5) as a compareson as well, before you can say the "hot cam setups" are bogus.
7 degrees is pretty excessive, especially considering you're already running a 248 intake cam. On a stock manifold, you're just going to put your powerband beyond what the rest of the engine could ever hope to do. I'd recommend a total retard of 4-5 degrees at the most. You likely would have noticed that the car started performing a lot better had you taken it above 3k. That much retard will make it run similarly to putting a huge cam in the car.

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Postby DjPantsSpecR » Thu Oct 26, 2006 5:15 am

Okay vinnie, this graph just kinda proves my point though. i'm talking about making top end power, as has been my point for quite some time. This graph shows how badly 248/248 on a stock KA sucks, but it shows what starts to happen as you open it up.

It looks like there are consistant gains of 8-10 ft/lbs from 2.5-4k in stock cams over nismos. Which is very attractive to many 240 owners. i dont know too many people who wanna lose 10 ft lbs there for 1500 rpms.

however, after you get through first gear youre at about 4k. youre down (with nismos) by 6 from 4-4.5k, but then they even out until 5, where there are gains of only about 4hp (nismos) for about 500 rpm. then stock cams fall on their face at 5500. At the end of this dyno, there is a 10hp gain over stock, and this ends at 6300 rpms. I can imagine that gains to 7k over stock are over 10hp.

Now what ive done with 248(+5)/248(-2.5) is shifted the power band to the right. i take more of a loss until about 4k where my torque peak is moved right about 500 rpms. this inturn is making more top end because it shifts the peak horsepower further right, so there is even more horsepower gains nearing redline. theoretically at least. you have to keep in mind that im trying to compliment a specific intake ram length, and the ssac 3in-2x2.5in n1s. something i know this dyno doesnt take into account.

obviously, this dyno shows how much more torque than top end you can make, and obviously im not only going to be trying this, but im going to retard it to the specifed specs earlier, as i already have gears drilled for this. i should be able to either prove my self wrong, or prove that it'll be even harder to get traction in first gear, and then i'll never even see that torque again.

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Postby struckinc » Thu Oct 26, 2006 6:10 am

right now i am running the altima 248 and the 232 exhaust. since i have .5 deg advance from stock on the intake i should retard my intake about 4 deg to drop it to 2 deg before tdc right? each tooth on the cam gears are equivalent to 4.75 deg right? so to do this people using the 4 tooth method should actually be going back 5 teeth. am i understanding this correctly or no..just trying to be sure

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Re: (struckinc)

Postby Bigvinnie » Thu Oct 26, 2006 12:40 pm

struckinc wrote: each tooth on the cam gears are equivalent to 4.75 deg right? so to do this people using the 4 tooth method should actually be going back 5 teeth. am i understanding this correctly or no..just trying to be sure
No you are not understanding. The degree from one tooth to the other is about 18.9Degrees. No matter what cam adjustments you make you can't go passed 12 degrees (retarded) from stock. It also isn't advised to retard more than 5 degrees for streetable engine setup's.

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Postby struckinc » Thu Oct 26, 2006 5:44 pm

sorry. i misunderstood. i thought i read somewhere that the teeth were 4.75 deg...thats what confused me. i took 360deg / 19 teeth = 18.94. as far as the 5 deg retard. is that a total of 5 deg retard or is that retarding the intake 5 deg from its stock setting of 1 deg atdc for a setting of 6 deg atdc?
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Re: (Bigvinnie)

Postby DjPantsSpecR » Fri Oct 27, 2006 10:53 am

just so happens someone posted this today. entirely stock KA. 232/232 vs 248/248.

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Re: (DjPantsSpecR)

Postby Bigvinnie » Fri Oct 27, 2006 12:16 pm

DjPantsSpecR wrote:just so happens someone posted this today. entirely stock KA. 232/232 vs 248/248.
I'm assuming the graph showing more HP is the 232/232 (nothing is properlly labelled).It seems to be a trade off in the overlap of the 248's. Torque is still represented as making more power on a set of 248's. Just looks like there needs to be a little seperation in the overlap to make more power.I wouldn't be surprised if a 1 or 2 degree retard on intake would extend HP...

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Postby DjPantsSpecR » Fri Oct 27, 2006 1:12 pm

no, the one that made the most horsepower is the 248 obviously. its nearly identical to the dyno you posted, it loses low end before 4k and then its greater for the rest of the rev range.

and after you shift youre never below 4k for a redline shift.

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Re: 240/232 Combo for SC'd KA24de

Postby tloof » Fri Oct 27, 2006 2:15 pm

Hey Dj,

As you know I am now getting near the end of finishing up all the fabrication for my upgraded SC'd conversion on my Frontier version KA24de that is retrofitted with a 240SX upper intake. I left the previous cam combo that I had installed in it for the original n/a swap (a 240/232 combo) because I felt that it would probably provide better low to midrange torque when cruising off boost, but now I am rethinking carefully about which cam combo setup would be the most ideal for a mildly boosted KA. I notice that you have been advocating and testing the idea lately about retarding a 248 exhaust cam for use as an intake cam so that you gain more top end flow without as much loss in the mid range as a normal 248/248 combo(presumably due to maintaining the same overlap as a 240/248 combo but with the later closing of the intake valve after BDC so that more intake flow is crammed in at high RPM because of the inertia of the flowing air & gas).

Also you mention retarding the exhaust cam a bit as well which would delay the closing of the exhaust valve a few more degrees after TDC (this would increase the valve overlap slightly more which is what Nissan did on alot of the later KA engines in the Altima & Frontier to increase the midrange torque when they stated closing the exhaust valve at 7 degrees after TDC vs the 4 degrees after TDC that the 240SX's used...I'm not sure I understand comepletely why that really works, so I guess I need to analyze all of this some more).

Now, since I have the benefit of 6-7 psig boost right off idle all the way up to about 5500-6000 RPM, I'm thinking that maybe I could benefit slightly in the higher 6000-7000 RPM range when the boost drops off slightly by changing out to a 248 degree cam for use on the intake side as well without the worry of any midrange loss due to the added boost in the midrange area. But for my boosted application I think that keeping the valve overlap smaller (like the 3 degree overlap that a stock 232 exhaust cam gives when the exhaust closes 4 degree after TDC & the intake opens 1 degree after TDC) would be better so that I don't get so much intake charge loss out the exhaust because of the added boost when the intake valve opens. Maybe even a longer duration on the exhaust might help some in a boosted application because of the elevated cylinder pressure a boosted engine produces (like going up to a 240 degree cam on the exhaust as long as I keep the closing of it no later than 4 degrees after TDC...perhaps changing out to a 248 degree exhaust cam would add even more power too?).

I am still concerned about maintaining as high a torque output in the midrange as possible for purposes of cruise conditions when no boost is produced, but of course added torque (& HP) is only a small throttle push away (but then that will just defeat the whole reason for having a recirculation valve on the SC'd setup so that increased fuel efficiency is possible off boost during cruise conditions!).

What are your thoughts on this? I am still leaning towards keeping the 240/232 combo in it, but maybe a 240/240 combo with 3 degree overlap might be the best overall combo for a boosted application. Hell, for all I know perhaps a shorter cam combo like a 232/232 would actually be the best overall since the blower will still cram boost in up in the higher RPM already, but my gut feeling is the greater duration will of course make more power though it would no doubt reduce torque in the midrange off boost during cruise conditions (the question is would that really even matter for a light weight 2950 lb Nissan 720 truck?). Unfortunately, what the Turbo guys use for a better cam combo isn't as applicable to a SC'd type engine since increasing load to make boost like a turbo requires isn't neccessary on a positive displacement SC'd conversion.

Any good thoughts out there on this subject?

Bigvinnie
Posts: 1079
Joined: Thu Apr 07, 2005 2:07 am
Car: 2004 Nissan Frontier desert Runner, 2014 Nissan Titan

Re: (DjPantsSpecR)

Postby Bigvinnie » Fri Oct 27, 2006 3:16 pm

DjPantsSpecR wrote:no, the one that made the most horsepower is the 248 obviously. its nearly identical to the dyno you posted, it loses low end before 4k and then its greater for the rest of the rev range.

and after you shift youre never below 4k for a redline shift.
Why is it that 2 torque curves almost ride side by side each other, while one drops off significantly????That shows a bit of some confuson for myself since when you look at the NISMO chart torque is significantly less using the 248???Where was the cam placement on that specific dyno????


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