would it be possible to swap out the VQ for an SR20DET motor from the 240? or even the RB26DETT? without lots of fabrication?

 

yes, it is the same engine as the samsung "maxima" in korea.

 

Sure let's take a 222 hp engine and replace it with a 200hp-ish engine.

 

well said Jeff.



For as much work as it's going to take, just turbo the vq already.

 

I just said it was possible, thats it.

 

y? would yo do that..just buy a 240

 

Sr20DETs came from 240s?

 

You could put a GE90B-115B in your maxima if you wanted. That would probably push your car to about mach 8.

 

240SX = KA24 not SR20DET
Silva/180SX/etc. in Japan has SR20DET
FWD vs. RWD any reason for concern?

Finally, as Jeff said, why would you when the VQ is better.

 

RB26DETT swap "without lots of fabrication" -

 

a vq better than an sr20det??????

i don't think so.

 

Why don't you think so?

 

Could you please refresh my memory as to how many 1500whp SR20DETs there are in the world?

 

SR20DET

 

Man...I SOOOoooo wanted you to chime in on that fools thread over on my350Z.com that pulled his VQ35 to put in a SR20DET for "better balance" and "proven power".

 

Welllll...you could put in an SR20DET from an AWD Bluebird...but, again, why would you want to?

 

I know...I thought of that, but he did say "SR20DET from a 240".

 

This is true

 

this was simply a question if it was possible. my apologies the 180SX/silvia/S13.

 

Yep it's possible and pointless unless you just want to spend money to be different and make less power.

 

SR20DET = lighter and smaller than crazy-turboed VQ35. That means better mounting in the engine bay, and less front-heaviness.

Better weight distribution.

Better balance.

Also.... what is an SR20DET if not proven and powerful? People know what to do with that engine a LOT better than they know what to do with the VQ35. It's just been around longer.

 

Not by a whole lot. Maybe 50 or 60 lbs. at most, if my research serves me well.

The 350Z has a 52/48 distribution as it is, and I remember reading Nissan designed the car to have that distribution on purpose. I'm not questioning Nissan.

Sure the SR20DET is "proven." Sure it's been around longer. Does that make it a better engine? No. You still have 2.0L vs. 3.5L. Much more potential in the VQ35. I also don't see how it's any easier to mod the SR20DET, because there's already numerous kits available for the VQ35 thanks to the 350Z/G35/Skyline community.

 

Let's see a Turbo VQ in a 240 like Broaner is doing with a 6 speed tranny from a 350z :>

I would prefer that over a SR20DET. I am not biased to the VQ or anything. :P

 

he's putting a modified stillen s/c kit on his though.

 

Point taken. You also have to take into account the size of the engine, though. Even if it's not any shorter in length, it will be narrower, and either way it takes up less space in the engine bay. That means you can mount it and all the associated piping really far back in the engine bay to bring it closer to the center of gravity. That is always a good thing in a car.

There's nothing magical about 52/48. What Nissan did "on purpose" was to make the weight distribution as close to 50/50 as possible for handling purposes.

Potential, yes... if by "potential" you mean power and torque. What about volumetric efficiency? Throttle response? Power delivery? Sure, you can make tons of power with the VQ35. But when you're dealing with a racing team that wants very specific characteristics from their engine, it may not be the best choice. Hell, it might even just be that the driver knows small turbo engines best, so that's what he was most comfortable driving. It all depends on what they wanted.

"Easier to mod" and "easier to get power out of" are two different things. Anyone can get more power out of any engine by slapping on a whackin' turbo and spraying lots of nitrous. That's not the point for most racing teams. You need power, but you also need behavior. You need to be able to craft the engine to do certain things in certain ways. In that respect, it must be at least as easy to do that with an SR20DET as with a VQ35 because the SR has been around so long and in so many cars and has been built up in so many different ways that there's already a HUGE selection of parts and experts to do it right, whatever "it" is. The VQ is newer, so it doesn't have that advantage. Period.

 

supposedly the QR25DE is better built than the SR20DE(T)... why not use one of those instead? even then, the VQ would be a better choice simply because you should have more power on tap at all rpm ranges helping move the larger cars you're talking about putting them in.

about the 52/48 and 50/50 weight distribution stuff, go take a look at the new lotus elise. those things handle incredibly well... their weight distribution is about 62/38 rear to front. not even close to 50/50 but will out handle tons of cars on the road. they made the elise to handle the best at 62/38 so nissan must've made the Z to handle the best at 48/52. its that simple.

 

Very good points. Those aren't really what I was trying to point out, I was going with a different approach, but very good points. +1 for you sir.

 

Again... the SR20DE(T) has been around longer in a greater number of cars, and has been tuned for a greater number of purposes (street, drag, drift, road race, autoX, etc.). It has the parts library and people (drivers and tuners) know it.

To say that Nissan paid the same attention to the Z's handling that Lotus paid to the Elise's handling is like saying Nascar pays as much attention to cornering as Formula 1. Different purpose, different focus, different amounts of development resources, WAY different levels of expertise.

We're not even talking about the same thing here. The Elise is supposed to be a go-kart. That's why its rear-biased weight distro is good: it accelerates better because it's got more weight on the driving wheels, it brakes better because it doesn't totally load the front brakes with weight transfer, and it corners better because it has innately better turn-in, which allows more grip-oriented tuning for the rear without creating understeer. This SR20DET 350Z, though, is a drift car. It's not supposed to get around a corner quicker. It's supposed to give its driver as many options as possible for creating oversteer or understeer at any given time. The chassis is supposed to be as neutral as possible so that the only time weight is biased to one side is when the driver transfers it himself. That's why it needs a 50/50 weight distro.

 

Hey Matt, perhaps you could take the 3.5L out of your Max and put a 3.0L?

 

What the ****k? The VQ35 weights 175 pounds. Me and bro lifted the damn thing together, and he's 5'7'' 130 lbs!

Again, BS.

Then explain me why there are maximas in the 11s with stock vq30s.

 

D00fd00d, what are you talking about? Power delivery: VQ35>SR20DET hands down, more torque, and available at lower RPM. Volumetric efficiency: VQ35>SR20, VQ35 is OVER 100% VE, SR20 is 90% VE. Heavier VQ? Not my very much.


Bottom line is this: Any car, you put a turbo VQ35 in it and it will be faster in every respect that a car with an SR20DET, will have more power, more linear power delivery, and the list goes on. There's really no arguing the point.

You can play devil's advocate all you want, but there's no escaping the fact that the VQ35>SR20 in almost every measurable category. There are few, like weight, that the SR20 has an advantage, but the power advantage of the VQ far outshines the weight difference in any speed contest.

 

I've done it like 4 times already. Sorry no pics or write-ups.

 

I'm pretty sure the VQ35DE is lighter than the iron block SR20DE, and I know the 3.5 is 35 pounds lighter than the 3.0, which was already very light.

 

if saying getting as close to a 50/50 weight distribution is best then lotus would have made their car as close to 50/50 as possible. they wanted the car as lightweight as possible and made it handle insanely well even with its current weight distribution. in most cases its hard to get a car to a 50/50 weight distribution so the manufacturer will make it handle as good as possible at the weight distribution it has.

granted the two cars are totally different setups but if what you were saying about the 50/50 weight distribution many sports cars would be designed quite differently.

the SR20 has an aluminum block. the CA series (CA18DET, etc.) has a iron block as does the VG, KA, RB, FJ, etc.

 

Ok. I know for a fact that the KA24 is heavier than the VQ30 (they weighted both when they did the swap in a 240sx) by something like 29 pounds, so that means the VQ35DE is about 65 pounds lighter than the KA24, so the weight difference between the 3.5 and 2.0 is probably trivial.

 

Fair enough. What I was trying to say was that the guys who made the SR20DET 350Z may have been looking for a different style of power delivery. I may have been wrong on one or two assumptions, but the point is that there's more than just raw power and torque @ rpm to consider when selecting an engine. People were poo-pooing the statement that the SR20DET was chosen for better "balance", so all I've been trying to do is point out what that could mean.


A few guys who know boost and know the cars is one thing. An entire sector of the industry supporting an engine is another.

And the weight distribution thing is not BS. SR20DET = less plumbing, smaller overall dimensions. That means more flexibility when arranging the engine bay, and that can mean better weight distribution. Simple math.


Re-read what I said. I never said that 50/50 was "best". I said it was more appropriate for some cars and less appropriate for others.

 

some magazine weight the KA and said it was supposedly right over 400 lbs. i know a dry VG30ET non-W block weighs about 396 lbs. i would think the VQ's would weigh way less than those engines.

something interesting to note, a guy was swapping a VQ into an RX-7 i believe and said the VQ was even lighter than the 13b. the rotaries do have a lot of iron in them but they are pretty small. can't be too overly heavy.

 

Yeah, I've heard those figures too. The problem with comparing engine weights is that sometimes people take different tacks when they define where the engine stops and where the "nonessential" bits begin -- i.e. with/without piping, starter, etc. Even if you weigh two engines with the same number of extras, when you're talking about boosting them and using them in a very specific high-level racing app, that weight may not be valid. I would think you'd have to put them in the car, tack on the turbos, intercoolers, and piping, tune them the way you want, and then see how things turned out. That's why I suspect that if you have to make, say, 600hp, you might end up with a lighter (albeit less torquey) setup overall if you use an SR20DET, just because you wouldn't need as much piping.

Hell, even if it isn't lighter, the piping arrangement would be simpler for an SR20DET, which would let it take less space, and that would mean you could pretty much arrange the engine bay however you damn well please. That's just as important, no?

 

WHAT!!! VGs weigh that much, i guess i need more boost

 

I believe the stock internals of both the VQ and the SR are good until around 400hp. Why not stick with the bigger displacement of the VQ and then turbo it? If you want more than 400hp, why not upgrade the VQ's internals?