Like the title says, Im starting to build my next 240 for this upcoming summer. I have found a 91’ Coupe with a good body/underbody so that’s taken care of.
The motor I have chosen is an sr20det due to the reliability, ease of swap, aftermarket, and cheap price. My last car was a 92’ Coupe with a redtop sr20det and i’ll stand by these motors forever because I couldn’t believe the amount of abuse I put it through, and how well it took it.
My goal when this car is complete is to have a very streetable, reliable, 300-350whp MAX. I also want this car to be very responsive, and to keep alot of my tourqe as low in the powerband as possible.
I plan to do this by purchasing an s15 sr20det with the six-speed transmission, and chaning the rear-end from the stock 4.08:1 to a higher gear. Also to help out, a lightweight flywheel, a lightweight pully set, carbon-fibre driveshaft, and lightweight rims.
why s15 SR? why the driveshaft? why the rear end? are all these because of the s15 sr?
im no expert but il throw my 2 cents in… s13-14 SR… gt2871R .64ar… z32 maf…walbro… 740cc… FMIC with vmount… large as possible turbo outlet and complementing 3" downpipe and exhaust. Tunning AEM is the best i believe but i went power fc because of my budget…Boost controller is a must. Good quality boost controller/solenoid will improve boost response, so probably in this case u get what u pay for here. Lightweight fly wheel and matching clutch for ur power goals.
In all honesty i would look at bings setup if u want low end power… however i wouldn’t call it a budget build once u build the motor.
But i think alot of people will agree that reliability is all in the tune.
Hey NoSkillz, ty for all the advice. My as far as I understand it; the s15 sr20det 6-speed tranny is the exact same as the regular sr20det 5-speed tranny’s plus an extra gear after 5th. Meaning the ratios 1,2,3,4,5 are the exact same gears.
I want a little more jump off the line and more grunt low in 1st gear (espically city driving) which explians me wanting to change the rear-end, but at the same time I dont want to make the 3800rpm @ 130km/hr in 5th gear (or whatever it is) any worse. So I thought the perfect resolution this problem is to just pay the $$ and get the s15 sr20det with the 6-speed.
I also heard that the 6-speed’s are a little more brittle but that should be ok since Im not planning for Huge power.
The reason I want the lightweight driveshaft, pullies, flywheel & rims is that I want to cut down on the sloppiness of my turbo motor and try to give it a more “snappy” N/A kinda feel. My main goal is to make this a very responsive, and grunty 240.
Specific wise, he said he wants a responsive, quick spooling, n/a feel to his car… so im guessing, greater emphasis on reliability and handling… so a reliable street car you can occasionaly take to the track.
Am I right? Im no ms. Cleo, but that what im assuming.
Specific wise, he said he wants a responsive, quick spooling, n/a feel to his car… so im guessing, greater emphasis on reliability and handling… so a reliable street car you can occasionaly take to the track.
Am I right? Im no ms. Cleo, but thats what i’m assuming.
Mr.K – I have experience with fabrication although im no pro, my budget is… well I dont really have a limit as long as its what I want and its done right. This can is going to be my everyday driver (in the summer) aswell as a car I plan on taking to the drag strip and race track occasionally.
Alright, a couple of crazy ideas to throw your way. I’m going to get shit for this.
Throw a Vortec 5300 in it. Its basically a 5.3L 'vette engine, and they’re a dime a dozen. They’re what you find in Silverados and such, so any junkyard will have 20 of them. I’ve heard its becoming a bit more popular with the V8 RX7 guys. Anyways, reliability is obviously a factor for you, since you’re going to be driving it every day, or close to it. The 5.3 is going to be cheap to maintain, easy to get the type of power you’re looking for, and its going to be a little different then what everyone else is doing, so its something to think about, nothing wrong with being original. It should be just under 300rwhp to start, and a Z06 cam/spring combo will get you at your 350hp target or above. If you have mental problems, the manifolds can be flipped around for a turbo setup…I heard 800hp isn’t out of the question with that exact setup.
The downside is obviously you’re going to throw a bit more time into it as far as fabrication goes, and thats why I asked. You can play with the mounting points to get the engine to sit right against the firewall basically, so the balance is going to be good.
The SR swap is a safe bet and I know of a friend who did it and was pretty happy with it, until he sold it for a GTR. With just about any swap you can think of, there is someone on the interwebs that has done it and can answer questions for you. An Rb swap isn’t out of the question either, but I would pick the SR over that particular swap.
skyline diff for a shorter gear
gt28rs for the turbo will give you your horse power goal gt2871r will give you 400ish but with more lag then the duel ball bearing rs
a good set of cams to help get back you torque
a good tune can also help with your torque and horse power
light weight flywheel
light weight pullies
aluminum drive shaft
injector upgrade
gutted interior racing seats (get all the weight out you can)
fiberglass or carbon fiber panels
etc. etc.
Mr.K – Wow dude Ive been looking into 240 motorswaps for about 3 years now and Never have I even thought about Vortec 5300. Thanks for the info i’ll look into that for sure.
Oni-Kyan – Hey bud thanks for the input!, so Im guessing you have same kinda setup as I want eh? lol
Hell, Im pretty dead-set on building my own but if your serious about selling your car let me know.
I’m throwing around the idea of doing one myself, so I thought I’d pitch it out there. Essentially that Vortec (also known as the LM7/LM4) is of a similar design to that of the LS1/LS6 thats used in the Z28/Corvette, and I’ve started reading about people doing them for budget builds, since they’re cheaper than an LS1 and can get about the same power. The intake on 5.3 needs to be swapped for an F-body one since they don’t sit as high. I found a thread of a guy doing something similar, so it might be worth a read: My '95 240sx 347cc V8 Project - LS1TECH - Camaro and Firebird Forum Discussion
6-speed tranny is a waste. Its fragile and hard to replace once you blow it up. The extra price youll pay to install an S15 motorset with the rear end can be saved and used for upgrades to hit 350hp on an S14 motorset.
Browse most of the 240 forums and youll see that S15 motors are rare because they really arent worth the extra money since you arent getting anything better per say.
The 2871R is proven to the numbers you want and is a very responsive turbo, stick with it. An AEM EMS is the next logical step (after fuel mods). This way you will have a car that runs properly and should be reliable.
Other than that, I hope you’ve got some cash cause a setup that you want aint cheap.
he is serious
and you will NOT be disappointed if you check it out.
Its one of the most SOLID 240’s ive been in,
ITS A BEASTT,
if your serious work something out with oni-kyan.
I’m telling you right now , if you want that kinda power. this guys car has it , and for the price he is selling, you wouldnt be able to make that set up for near the price!
i’m with v8 man …but then i never liked sr’s, i’ve owned and driven quite a few… i dunno they don’t work for me… i like torque hence why i have an rb25 in my winter beater and a drag rb26 for my regular car. and it’s way way easier than people tell u it is… i just think it works better for your purpose, you can chill low rpm all day and still have tons of power with that sr you can’t. fyi i’ve driven every sr s13-s15… and from stock to big bore kits with race cams and a 3037r… they didn’t make me happy…
theres full kits for ls1’s and being chev hasn’t changed the basic small block in years, you should be able to use it to mount pretty much w/e small block u want. or do it your self save money and have your own light wieght shaft made they are very affordable …and it will be insanely reliable at your power level and ultimate cheap for parts… and you can use a corvette 6 speed which will definitely not be a problem with your power and tons more un-like an sr with s15 trans , and you still get a 6spd…
but hey do what you want 350 isn’t super challenging to achieve on anything u want to put in there. but if u want torque an sr just isn’t it haha
a quick spooling turbo is a supercharger!! this has been a topic before, the guy with a pathfinder S/C on his ka24de(i believe), i don’t know the hp numbers off my head, but a S/C would give u the snap and responsiveness you are looking for. not to mention breaking away from the heard and doing something different. the chevy motor would be good, it’s ment to move a truck with twice the weight!! it should move a 240 pretty good!!! parts are common ,easy to get. not to bad of an idea if u have the time,money and skill.