NICO History in the making...

These look like really great ideas! Keep it up!

Yeah this is awsome. Ive read this thread like 20 times allready its clicking now. I wanna see it done

Update on the SC drive system,

Attached are photos showing my progress on the two idler pulley support brackets and SC drive belt layout. The upper idler support bracket is entirely finished with the idler pulley mounted on it. The lower idler support & alternator mounting bracket is almost finished, but several mounting holes with spacers are not drilled yet along with the idler pulley not mounted yet (I have the idler pulley C-clamped into position for the photo to give a good idea how the belt routing goes). I still have to weld a tab on this bracket for the alternator adjustment bolt, and a small section of angle steel onto it for direct mounting to the pulley end of the supercharger snout so that heavy belt tension won't pull the SC drive pulley towards the engine block.









I'm getting close to finishing now, but I also need to make a supercharger case support bracket that ties to the engine block in the same location as the old intake manifold support bracket. I figure that since Nissan felt it was necessary to support the weight of the intake manifold & plenum that the SC weight should also be supported since it is even heavier!

Man there sure is alot of extranous brackets and such to custom make!! (what a pain in the ***!). No doubt Thomas Knight's SC kit would sure reduce the time required to mount one of these babies, but unfortunately he doesn't make an adapter and drive setup that works on a Frontier variant of the KA24de engine. Besides, other than the labor time required to figure all of this out and make all this bracketry (free for me since I did it all myself) the material costs have only been about $200 total for the SC adapter plate, idler support brackets, all idler pulleys, and the custom crank dampener drive pulley. Doing it all myself has saved me $1000 compared to what Thomas Knight's sells his kit for. Of course if you had to pay a shop to do all this custom development & fab work then figure about $80/hr for at least 30 hrs to get it done, which is about $2400 + $200 in materials = $2600 total. Looking at it that way indicates that Thomas Knight's kit isn't too bad afterall, but of course with all the development patterns in hand any additional kits could easily be made in no more than about 4 hrs total labor (or about $320 + $200 in materials = $520 total + some reasonable profit amount...maybe $600 to $650 total...the $1200 for Thomas Knight's kit is really more than I think it should be, but I guess you can't criticize him too much all things considering!).

If any of you are handy at making things, then you could easily match what I have done for no more than about $250 total (the salvage SC, 370cc SR injectors, and reprogramed ECU will add an additional $850 or so, for a total SC conversion cost of around $1100). If you aren't too handy at making things, then buy Thomas Knight's kit since it will be a bargain in comparison to a shop attempting to do this as a one-off conversion!

Great work, can't wait to see some numbers and bay pictures, I feel for you if you ever snap your alternator belt though. Are any of the idler pulleys adjustable? Personally, I would make a slot for the last one, as that one looks to have enough room.I can't think of any adjusting bolts that would be long enough. A 95 Dodge Stratus' idler adjustment bolt is about 3 inches if memory serves. Either way, keep us updated.

Oh, and get rid of that dam Fram haha.

Actually the alternator belt is easily changed as long as the SC drive belt is removed first (which is no different from the original power steering V-belt that is normally located in that same position).

The two idler pulleys on the passenger side of the engine are fixed pulleys that are supported by grade 9.9 metric 12 mm bolts that fit thru the plate steel support brackets (they go thru stock Nissan spacers that fit into the bearing of the pulley itself). The idler located on the drivers side is an adjustable one for tensioning purposes and is supported on a stock Frontier bracket & support bolt that the original adjustable power steering idler pulley was located on (it is a slotted bracket with tensioning bolt on it).So, I have it all covered for tensioning purposes!

I see, I thought they were all fixed, hence my thoughts on the belt replacement. How much boost do you expect it to run?

With the 5" dia custom crank pulley and stock Xterra 2.64" blower pulley it should make a max of about 7.5 to 8 psig boost (this is based on a guy that goes by the user name Nomadtrash on the ka-t.org site which is currently making 6 psig boost with a 4.75" crank pulley and 2.64" blower pulley, and has also calculated that a change to a 6" dia crank pulley will bump him up to about 13.2 psig... so I figure my pulley sizes will make close to 8 psig or so). In reality I don't really want to make more than 7 psig boost since there is no intercooler on my installation, so I will probably change out the blower pulley to a larger size (probably around a 2.75" dia blower pulley). Limiting boost pressure to 7 psig max should net workable intake air temps without an intercooler, and should come close to about 210-215 rwhp in this application. Not bad for only a $1000 total investment!

No, that's not bad at all, I'm very interested in home brew junkyard boost options. I'm sorry to keep hassling you with questions, and I'm sure if I searched the web hard enough I could find my answer, but... Do you happen to know the maximum efficiency of the charger?

According to Magnuson's printed literature they say that these latest generation Eaton blowers have 95% volumetric efficiency. The adiabatic efficiency is closer to about 60-65% or so.

tloof would u be willing to make/sell the brackets for the smooth pulleys ...??? and flange adapter???

or atleast make a blueprint we can download and trace and cut and stuff u know what i mean.. like detailed measurements and insructions..

im very interested in how this turns out...

this thread is making me want to try this on my spare engine....

Naw,

I've got too many other projects that I need to finish before taking the time to make brackets & a SC adapter plate for others! Now I could trace out the finished brackets & adapter plate on some cardboard for others to use as a template (and label all hole diameters that need to be drilled), but keep in mind that my setup will only work for those that use a custom made 6 groove serpentine drive pulley in place of the power steering pulley and also only on a Frontier variant of the KA24de engine.

I think it is possible to make it work on a 240SX with some slight changes, but that will have to be worked out by whoever attempts to do it on their own 240SX engine. The lower idler plate will definitely fit the same on the 240SX, though the spacers that attach it to the timing cover will need to be a different thickness than what the Frontier version requires. The top idler bracket will probably be similar but may need to be extended more towards the drivers side of the engine in order to be bolted up to the available bosses or mounting bolt holes on the 240SX front head cover. That top bracket will still require a Frontier power steering pump bracket be installed on the 240SX head for support on the passenger side of it which will also require special spacers to get it to fit up just right. Another alternative for a 240SX installation would be to just bolt a smaller plate to the Frontier power steering pump bracket and install a single smooth adjustable tensioner pulley on it and then run the drive belt directly over to the power steering pump drive pulley that is located in its stock position on the drivers side (this would eliminate the need for the larger upper support plate that I have on the Frontier type KA24de engine).

I still have a bit of massaging to do on my support brackets to get them just right, so it will be a little while yet before they are totally finished since I am going on vacation for two weeks on Sept 30 (I won't get back on this project until after Oct 15).

ok thanks for the great info and have a great vacation then come back and finish it i wantg vids lol

Hey tloof! great fabrication! I had to join just to reply. I am thinking about a similar hybrid mod and I don't know if it's possible, but you probably do. I want to put a 95 ka24de head off my 240 onto my hardbody (97 ka24e), and use the manifold, fuel, harness, etc. The headgaskets are the same on the block part, so the bolts work, but the rear timing covers and gasket are different. Any hints? Or could I just throw in the whole 240 engine in despite the 4wd and diff between auto (car) and manual (truck), and just swap the accessories? I have to change the headgasket in my truck anyway and taking my 240 engine will force me to get an sr20!

here's the 240 gasket

nice KA24de-S (supercharged) but shouldnt one pulley be really big and one really small like the one that does all the turning of the belts be big and the superchargers be small so that the belt being turned by the big pully would be doing less work to make the belt move faster or what not and then the pully on the supercharger be small so it turns really fast . I havent put much thought in to it so i could be under thinking it and is that a wooden adapter. nice setup tho post a vid when ur done.

**** i was looking at the wrong pulley sall the big one and didnt c the supercharger pully is small oops ok ill just not say anything any more

wouldnt it be ka24deR im pretty sure that R is for supercharger when it comes to nissan

This a great write up and the reaosn i joined this forum ... thanx for all the info

so, if we don't have A/C, one could conceivably make one bracket that just has an adjustable pully, no? so you'd go straight off the crank and up the the blower, then a tensioner. Would be very simple without the A/C.

Hey Hardbody Silvia,

If you want to swap a '95 240SX head onto your '97 KA24e block then you will need to get a Frontier timing chain cover, timing chain & sprockets, & distributor so that it all will mate up with the 240SX head & the Hardbody oil pan. You also will need the Frontier front head timing cover, power steering pump support bracket, power steering idler support bracket, and front support plate for the conversion. You will have to relocate the temp sensors on the 240SX intake to the top side via custom welded bosses and plug the ones on the front of the runner in order to get clearance to the Frontier power steering pump setup (the power steering pump support bracket will also need to be trimmed on the backside to clear the intake manifold).

By the way, NO you can't use the DOHC KA24de 240SX engine block in a Hardbody truck, it has a front sump oil pan & timing cover design that is not retrofitable with a Hardbody type rear sump oil pan (the rear sump pan is required to clear the steering linkage).

As for the wiring, you can reuse the stock Hardbody wiring that is currently in your truck with a few modifications to work with the 240SX intake system. You will also have to add and wire up a knock sensor somewhere on the KA24e block since it doesn't have a boss for the sensor like the '98 up Frontier KA24de block has (I would just mount the knock sensor onto the passenger side motor mount to simplify the installation). Since you have a '97 hardbody truck you will have to use an OBD2 ECU from a '96-'98 240SX in order to be compatible with the OBD2 systems that are already in your truck. The ECU connector on all the OBD1 '91-'95 Hardbody trucks is the same as is used on all the '89-'94 240SX's, but the '96-'97 Hardbody has a different type of ECU connector since they have an OBD2 type system. I'm not sure if it is the same ECU connector as is used on the '95-'98 240SX's, but if not you can always relocate the pins from the Hardbody type connector into a 240SX type connector in order to use the OBD2 '96-'98 240SX ECU (Note: even though the '95 240SX connector is the same as the '96-'98 240SX models, don't use a '95 240SX OBD2 type ECU because it doesn't have the canister purge & fuel tank purge functions that all the '96 up vehicles have, and it has different type O2 sensors...four wire vs three wire types). I actually researched all of this for a future possible upgrade from my old 720 truck to a later model Frontier truck using the same supercharged Frontier variant engine I am now building for my 720 truck, and I found that the '98 up Frontier has the same OBD2 type system as the '96-'98 240SX, with the exception that the Frontier uses an entirely different type of ECU connector (damn the bastards at Nissan for doing that!). It turns out that the pins themselves are exactly the same pins as is used in the '95-'98 240SX ECU connector, so I can just relocate them to a 240SX connector thus allowing the existing wiring harness in the Frontier truck to be used without having to attempt to change out to a 240SX harness (there are two sized pins used in these ECU connectors, but the same functions are used on the same size pins for both vehicles). My guess is the '96-'97 hardbody uses the exact same pin types on the ECU connector, so you could probably do the same if the connectors themselves are not the same!

One other thing to mention, if you use the KA24de 240SX head on a Hardbody KA24e block with stock KAe pistons, then the compression will end up being about 11.1 to 1 which is way too high for street use. You will need to change out to 240SX KA24de pistons if you want to do all of this. It would actually be easier & cheaper to just go buy an entire low mileage Frontier motor for swapping into your hardbody truck, and then upgrade the cams & valve springs to 240SX items and then retrofit the 240SX intake system onto it. This is what I recommend that you do, since it will save you alot of time, expense, and grieve in this conversion in the long run!!

Hope this helps you out!

Xero,

Having no AC system will not eliminate the bottom idler bracket with my drive system since the blower is driven by a custom 6 groove pulley that is mounted in place of the original bolt-on 3 groove power steering drive pulley. Now if you want to drive the blower with one of the stock 4 groove pulleys on the crank dampener, then you would have to use the alternator drive pulley (the center one), otherwise trying to use the inner 4 groove AC drive pulley will cause interference between the blower drive belt and the alternator itself. Personally I would stick with the method I am using and then you can still keep your AC system functional (plus the 6 groove drive belt won't slip under boost like a 4 groove belt will most likely do... especially at higher boost levels).

Now, I should point out that the center 4 groove pulley is what Thomas Knight is using on his SC conversion kit to drive the supercharger, so that would eliminate the need for the bottom idler that I have on my setup since the alternator pulley itself acts as one of the idler pulleys. For a 240SX conversion his method may work well enough and thus avoid the need for a custom crank pulley like I have, but any Frontier type KAde variant will need to go the route I went in order to keep all the accessories functional.

reallly nice work. hope it turns out goood.

well, I don't have A/C to begin with, so it's not something I can really keep in my particular application, that is. I also don't have a clutch fan, I'm running dual electric fans, so I don't have to worry about that either.

My idea is to still have the bottom idler, but use it more as a tensioner, and have all of it just stick through the stock 4-groove belt, but have the blower running on its own 6-groove belt, like yours. Only difference is that I don't have to route it out to the A/C, since I only have 2 belts, one goes to the alternator and water pump, the other goes to the power steering. It's no problem for me to make a crank pulley, I just wish I would have taken dimensions off of that ASP pulley I had before I sold it, would have been nice to make an underdriven pulley for the accessories plus adding the 6 groove pulley for the blower.

I liked the idea so much I got a blower (Frontier Eaton M62) off eBay, it was shipped yesterday

--> Keep it up homie!!1 by the time you're done Iwill get my 240 SC or KA24DER ...+1,000,000,000...

tloof I am BLOWN AWAY by your knowledge on the topic!! This is 10000x the help I have gotten so far on the topic! Most people say "why would you do that" or "that's stupid" but now I'm on the right track. THANK YOU for this precious info. I will get to this project asap, which still may be a month or 2. Frontier parts huh? guess that makes sense. I guess I can start securing those while I plan to do the conversion. I'll keep watching your thread for sure until I have something to contribute!

Hey Hardbody Silvia,

You might want to consider another option of just supercharging your stock KA24e engine instead of upgrading to a DOHC head on your KA24e engine block since you have a Hardbody truck. The Hardbody has a higher hood line than my old 720 truck, so that makes it possible to fit the Xterra blower underneith it by mounting it onto a '89-90 SOHC 240SX intake that is retrofitted onto the Hardbody KA24e engine. The same method of mounting the blower case to the lower intake runner part of the manifold via a 1/2" thick aluminum plate can be used to do this as I am doing on the DOHC KA24de engine, except the stock SOHC type 240SX intake has the plenum on the top side vs the bottom side like the DOHC 240SX intake does (the blower is mounted in place of the stock plenum in either conversion). I first tried to do this on the SOHC KA24e that I originally had swapped into my old '85 Nissan 720 pickup, but the blower drive pulley just touched the front of my hood when I mocked it all up (I did however use a thicker 1" thick mounting plate when I did the mockup, so using a 1/2" thick plate instead would have possibly worked on my 720, but for sure it would fit into a Hardbody truck!). There is enough room to fit the throttle body directly onto the side of the blower's inlet port via a 1" thick aluminum adapter plate, and the AAC & air regulator valves can be remote mounted elsewhere and be attached to that adapter plate via a threaded hose fitting. Some sort of air inlet duct will have to be custom made that runs over the rear of the valve cover area and into the throttle body to make it all work. Also, the power steering pump will have to be relocated to the drivers side via a custom bracket made out of welded up plate steel sitting just above the distributor (use a power steering pump from off an Altima for such a conversion since it has the inlet port located on the opposite side of the pump in comparison to the Hardbody pump). The original Hardbody power steering pump mounting bracket should be left on the passenger side of the head and used to mount an adjustable tensioner pulley onto it for tightening up the blower drive belt (using a smooth metal idler pulley from off a 3.8L GM V6 mounted on the original Nissan power steering pump adjustable tensioner shaft and bushing is ideal for this setup). The lower custom alternator & idler support bracket I made for the Frontier type SC'ed KA24de engine conversion into my 720 pickup and the custom bolt-on crank dampener blower drive pulley are the other remaining items that need to also be made in order to complete the SC'ed conversion on the SOHC KA24e Hardbody engine.

I suspect that a SC'ed SOHC KA24e engine will probably come close to making the same HP that a SC'ed DOHC KA24de makes (or at least within 10 HP of it), so it would be a great way to go for any Hardbody guys!!

Just another idea to consider!

well it's a great idea and I want to do it. Of course, money is the one thing holding me back. When I do have some extra cash to play with, I will certainly put it into my silvia, it just makes more sense. =] However, I have always had it in my head that I can use any upgrade to my advantage, so if I put a new turbo on the sr20 I can maybe use the old one on my truck for a little extra gain (just a custom exhaust manifold, head gasket, and some piping is all it should take). I haven't researched the supercharger yet, what's it running? I guess $1700 +/- 500. That would help making one hell of an off roader, which I would surely enjoy. Regardless, I plan on using this truck for work, hauling tools and materials for carpentry, so I had less desire for a powerhouse than I did for a more economical machine. I know with a modified 240 head I could gain some good power without too much more gas guzzling. Also, the truck is BURNING gas at 3500 rpm at a mere 73 miles an hour, which is friggin rediculous. In my last trip to the beach I had to keep it under 65 the whole way to keep it even close to good mileage. Being optimized for 50mph in top gear isn't the best idea. I know my 240 engine has a 1k higher redline, so I'm hoping it has a more gradual fuel in the 240 ecu. (I found a sweet program for tuning nissan ecu's on my old computer, I'll have to see if I still have it or if I can find it again. Very nice!) Anyway, throwing the 240 head (which would otherwise be useless) on the truck seems like a good way to tighten up my engine for another 100k and still gain some decent power. So... how's the gas mileage compare w/ the supercharger? If it's good I still may consider it but I'll be damned if I'm missing out on the extra 10hp you mentioned at an extra cost of .00 a mile! So 240 head it is. I would rather avoid buying the whole frontier engine and just go junkyard diving on one with a nice list and camera and tools. Reason being I have the 240 motor already, and there were only 5 things you mentioned I would need. Additionally, I have a '92 hardbody which I have destroyed with a tree, heh, and I was planning on mating the '95 240 head to the '92 block, then dropping it in whole to use the '97 hardbody electrical, since that would save downtime on my truck. Are there any differences in the '92 and '97 hardbody blocks? Hey man, btw, whered you get ur phd in nissan engine science? =]]]

PS, when I get to this (just gotta build a garage first!! no sweat..) lemmie know if you need that '95 240sx ecu since I already have to get a '97 one.

Hardbody Silvia,

I guess your '97 Hardbody is a 4x4 model and that's why the eng RPM is so high in cruise? Anyway, the DOHC 240SX head & intake conversion isn't going to help out your fuel economy at all, in fact it will probably make it slightly worse since the DOHC KA24de engine dosn't make quite as much midrange torque as the SOHC KA24e engine unless the lower duration Frontier truck cams are used (at that point the KA24de engine is only good for about 3 HP more than an equivalent SOHC KA24e engine...140 HP vs 143 HP). The point I am trying to make here is that there really is no real gain by upgrading to the DOHC head unless you plan to go for high RPM power only. Also, I wouldn't ever recommend a turbo for use in a truck, the supercharger would be way better due to its instantaneous boost off idle and up thru the mid range where you really need the added torque & HP. The supercharged engine also gets virtually the same fuel economy in cruise as the n/a version due to the recirculation valve preventing the production of boost (turbo engines always get slightly worse fuel economy than a n/a engine). If you want better fuel economy in cruise than you need to change out your OD gear set with one from a 240SX (it has a 0.759 ratio vs the 0.833 ratio the Hardbody truck has). That change alone will make the most difference.

By the way, you are kidding yourself if you think it will be cheaper for you to convert your Hardbody engine to the DOHC head than just buying a low mileage Frontier engine. The Frontier engine can be had for about $800 vs the new pistons, bore job, and total rebuild of your Hardbody engine that will be required for such a retrofit (those costs alone will be more than the $800).

The only reason I am changing out to a Frontier version KA24de over the KA24e I previously had is because that is the only way I can get the supercharger to fit under the hood in my 720 truck. You on the otherhand can fit a supercharger on the SOHC KA24e under the hood of a Hardbody, so that would actually make more sense. An as far as the cost to do so, my total conversion costs will be no more than about $1000 (try to match that with a turbo conversion...it just can't be done!).

I already have a '95 240SX ECU, so I don't need yours (actually I need a '96 240SX ECU if I ever decide to transplant my SC'ed KA24de in a '98 up Frontier truck).

Excellent points about the idea. I will probably still do the head conversion tho, not the turbo. I am mainly basing my goals off of the big difference in how my 240 was so much more cruisable. It had all the power to keep going as fast as it was, unlike my truck which loses it on highway hills. The hardbody does handle fine at speed w/ a gas bill. My truck has plenty of power midrange, but my car wasn't lacking either. I don't think I'd notice a difference, but if the charts are available, I'd love to see them. Also, I do redline pretty easily once in a while, and I would like the extra 1000 rpm. I never heard such good insight to the hp curve etc between the 2 engines, but now that you break it down, I do understand what I'm lacking. I would love a supercharger if I could a) disengage it and b) afford it! You didn't mention the bill =] . Basically I want the same thing with more cruising potential and higher rpm. Since I have a 240 engine already, wouldn't those pistons work? Maybe the 240 is a wider and shorter bore? I was under the impression that KA24s couldn't be bored much because of their low wall to wall clearance. I could bore out the engine with a drill press and honing bit to save some cash; my friend and I did his chevy 350 with good results. I can assemble an engine. Yes, I guess the real problem is the gearing. I have an auto 240 so I can't swap tranny gears. Would the OD gear be interchangeable? Or I could get just that gear.. I was thinking just changing the transfer gase 2H gear, if there is one from the v6 or something that is higher, or the differentials if I have to. What do you suggest? Thanks again man for all the helpful info. Btw, for me turbo would be cheap (free) if I just fabricated the headers (of stainless tubes), downpipe, and the intercooler piping. For headers, the best is to use equal length tubes to fit, getting the angles of piping to bend 90 degs over a certain distance. Use the same bends of copper tubing covered with copper pipe insulation to get an idea of fit. Next, downpipe and intercooler piping is just point to point, from intake to front to turbo. Yeah it is a little bit of an endeavor, but I would like it and it would be a fun machine. Since the supercharger is that cheap, though, that's prolly a better idea.

ps The '96 240 ecu would control your frontier engine? What year?
Modified by hardbody silvia at 8:04 PM 10/22/2006

Hey, tloof!I've just got to say that I am blown away by your knowledge and innovation concerning the KA motors! I just found this forum after years of searching and prying for any information about modifying the KA motor and especially when it is still powering a truck! I drove my first '92 hardbody ka24e to 328k miles, and was searching for information about the feasibility of the SR swap, when it was totalled by a driver in a diabetic coma. I purchased a 2WD manual '02 Frontier ka24de model, and am now searching ways to add power (and if possible, better handling) without being a master fabricator. Will the turbo kits available for the 240 version work if I swap the intake manifold? Do I need to switch out the ECU with the '96 240? (and if so, why?) My brother just finished a SR swap in his S13, and suggested perhaps switching out cams from the old KA motor? I know you are busy, but whenever you get time, your advice and suggestions would be truly appreciated! (Excited about finding this forum!!!)Thanks a ton!hessianben