C18 vs SR20

[GRiDRaceTech]

I was thinking about this thread yesterday at work. The S13 is inherently front-heavy, but here's what I've figured out: any arguments about the weight of the KA versus the SR or CA are pretty much null because even though the KA weighs more than the SR or CA, they are both turbocharged. As such, they have oil lines, intercooler piping, a blow-off valve, and an intercooler. That should add the 35-45 real pounds of difference between them, making them roughly equal. However, when the KA is turbocharged, then we add in the weight of the turbo, oil lines, intercooler piping, a blow-off valve, and an intercooler. That'd make it a heavier engine and add more weight to the already heavy front end. This realization has led me to sort of want an SR or CA, (probably SR due to more aftermarket support) as I favor handling over raw power. (I'd keep the intercooler setup side-mounted for better distribution I suppose, although it would mess up the crossweights. But that's a different discussion for a different time.)

The reality is that each engine has its merits. The SR20DET has tons of aftermarket support, is generally stout, revs like crazy and can be had with relatively low miles for around $2500 including transmission and harness. The CA18DET is stout, has a high redline, but usually has lots of miles and thus is relatively cheap. There's also a certain rareness factor there. The KA24DE can make tons of power with low boost and is pretty strong, too. Size is a revving problem, though.

Go with what you want; horsepower isn't everything.

[marshun]

and where did you get your info about the KA being that much heavier than the other two motors? (CA and SR). because when i did the swap on a friends car, and we weight the motors for fun, it wasnt enough of a different to throw off the balance of the car.

and as for the remark about the 240's being front heavy, theyre not. you can even look online for that bit of info.

[nissanguy_24]

Originally posted by marshun
and where did you get your info about the KA being that much heavier than the other two motors? (CA and SR). because when i did the swap on a friends car, and we weight the motors for fun, it wasnt enough of a different to throw off the balance of the car.

and as for the remark about the 240's being front heavy, theyre not. you can even look online for that bit of info.

S13s are front heavy. they have a slight front bias. it verys so much because of all the different engine and front and body combination. But they are all between 50-50 and 55-45. The only other alternative is a rear heavy car. and they simply are not that. Most S13s are going to be around 53-47. Everyone who has weighed there car on corner weights gets numbers around here.

He said the KA and the SR are about similar weight. However once you add the turbo hardware and the lines ect.. to a KA it becomes even heavier. SCC says the weigh is about 5 lbs more on the KA. they have no reason to lie about that so i assume its true. Also anytime you add a front mount intercooler you are adding more weight, and to the worst spot for these cars. the very very front.

Now thats a problem on all engines. a S13 can be balaned out realtively easily, However from the factory they are all alittle front biased.

However sence you are dissagreeing with everyone else on this fact, feel free to look the info up online to disprove it.

[marshun]

the weighing of the motors was from first hand experience. although the KA didnt have a turbo and we didnt weigh them with intercoolers. its like a 40lb difference (give or take some). hopefully you see that this hardly makes a difference. not anything worth mentioning anyway

and you even stated the balance on the car. its a good balance on a stock car. so thats nowhere near front heavy. drive a truck and tell me what front heavy is.

[nissanguy_24]

Originally posted by marshun
the weighing of the motors was from first hand experience. although the KA didnt have a turbo and we didnt weigh them with intercoolers. its like a 40lb difference (give or take some). hopefully you see that this hardly makes a difference. not anything worth mentioning anyway

and you even stated the balance on the car. its a good balance on a stock car. so thats nowhere near front heavy. drive a truck and tell me what front heavy is.

i didnt mean to imply they were grosy front heavy, however they do have a front weight bias. thus the term..

[GRiDRaceTech]

40 pounds makes a difference. If the car weighs 2700lbs, (S13 coupe curb weight, no options) that 40 lbs is 1.48 percent of the car's overall weight. When you're trying to get a car balanced, that 1.48 percent is a big amount. I suppose you could mess with static heights to throw around the weights a little, but that's still 40 lbs heavier. The fact that it's 40 lbs in the front and up high is important. The entire engine is above the unibody's lowest line, so it adversely affects handling. We want that weight down low, if we have it at all. That's why 40 lbs matters.

The S13 is nicely balanced from the factory, but it could be better. It's more likely than not to have a 53/47 distribution, like nissanguy said. If we saved that 40 lbs, that would take us down to a 51.52/48.48 theoretical distribution, which is great.

But add the intercoolers and stuff to the SR and CA and they'll weigh about the same as a KA. Best case scenario: SR20DE with 200hp. No turbo, no intercoolers, no BOV, no piping. Just light weight. Again, it's up to you.

[Feint]

Rip out the a/c and remove the the power steering,that'll take care of the weight difference.

[98BlueStang']

Buy a cheap domestic SR20DE, buy the extra compeonents (engine harness, turbo manifold/ intake manifold, etc.) to make your own SR20DET and put that in the car. This way when the smog check comes along, you can say it is a legal engine with an applied turbo...think this will work?

[98BlueStang']

You could also remove the a/c like feint said and relocate the battery to the rear of the car. Should work

[new_to_drift]

i dont live in CA so i dont think that i ned to worry about the smog emissions laws.I really want to get C18 engine swap but im not sure where i can parts for it.

[Ichi-Go]

You should check out NICO forum for more info on the CA. I love that motor and wish I had a 240sx to put it in . Also all you guys that are worried about weight balance should already have your batteries relocated to the back because that is 25-30lbs right from the front to the back. Also I wonder how much of a difference putting your passengers seat all the way back would make. I dont think the weight (under 50lbs) makes that much difference on a stock 240. If you have full coilovers with the correct spring rates and dampening and everything already adjusted correctly then it would have a big impact on handling but before then I think that 40 pounds makes little difference.

[marshun]

Originally posted by nissanguy_24
i didnt mean to imply they were grosy front heavy, however they do have a front weight bias. thus the term..

for a while i forgot what happened to this thread. :P

but yeah. sitting still theyre front heavy. i agree. but while the car is moving, even for stock, its good.

feint- we cant really remove the power steering if you keep the KA cause its also the acting tensioner pully for that belt. but if you put in the SR then you can ditch that.

but idunno about you guys, but in between runs its nice to have that AC blowin. :P

but removing AC (completely, all lines and everything inside of the dash) will remove quite a bit of weight. and moving the battery is a nice touch too. makes the engine bay look cleaner.

[nissanguy_24]

Originally posted by Ichi-Go
You should check out NICO forum for more info on the CA. I love that motor and wish I had a 240sx to put it in . Also all you guys that are worried about weight balance should already have your batteries relocated to the back because that is 25-30lbs right from the front to the back. Also I wonder how much of a difference putting your passengers seat all the way back would make. I dont think the weight (under 50lbs) makes that much difference on a stock 240. If you have full coilovers with the correct spring rates and dampening and everything already adjusted correctly then it would have a big impact on handling but before then I think that 40 pounds makes little difference.

40 lbs here. 15 lbs there, 60 lbs here, 30 lbs here. And pretty soon it adds up to real weight.