S14 Power and Finesse

[twistedsymphony]

Coming Soon...



Yes, that is an LS1. Yes, it came out of a Corvette. Yes, it is going in my 240.

--------------------------------------------------------------------------------------------------------------

Update #1: 8/28/2008
A little background.

Project Goals
Original buying the 240sx I knew I was going to swap the motor before I even bought it. I had looked at what was involved, what the differences between the USDM and JDM spec vehicles were and I had decided that I wanted to build the car to be EXACTLY like a full equipped JDM kouki Silvia, except Left Hand Drive, and with some light modifications.

Most of the use of the car would be just for cruising around with the occasional track day for fun.

I started researching what parts I needed, where I could get the parts, the legalities of it all, and what I could expect when I was done.
It didn't take long for me to realize it wasn't going to be nearly as cheap as everyone made it sound. It also didn't take long for me to realize that I wasn't going to get the kind of power numbers I wanted without spending a bundle more on top of the swap either. Ideally when done with the swap I wanted a car that was a step up from my WRX, that wasn't going to happen with a factory spec SR... so I'm looking at $7K worth of motor and parts plus all kinds of work, and the power wouldn't even be all that spectacular unless I spent more on top of that upgrading the turbo, and other crap.

I had my goal in mind so I started looking for an SR anyway. I was pretty disappointing with most of what I found, the market was slim pickins for SRs and it seemed like even if I found one it was a crap shoot as to whether or not it was going to last, lots of shady JDM dealers... and to top it all off running the motor on the street would technically be illegal too.

I decided that I shouldn't just go for JDM spec, it would be a lot of money and I probably wouldn't really enjoy the end product that much... so the first thing I was going to do is ditch the idea of an SR and just look at all of my engine options...

The new goal: Build the most well balanced car I can in terms of handling, raw power, looks, and comfort.
I want to build the most capable S14 possible, but at the same time have it look and drive as comfortable and be as reliable as an OEM spec car... I'm not going to compromise performance for style, but I'm also not going to compromise comforts (AC, interior trim, etc.) or Reliability for performance.... Power and Fitness.

Obviously there are trade offs with everything so my choices would have to provide good balance between improving the vehicle's abilities but not sacrificing too much in terms of comfort and reliability in the process.


Why go LS1?
Once I changed my goals I took a step back to re-evaluate my decision to go SR, what motor would REALLY be the best for what I wanted to do with the car?

KA-T
SR
RB
2JZ
VQ

KA-T... bolt on turbos are nice but reliability is really sketchy since the motor wasn't built for it, I could rebuild the motor but then I'm spending just as much as an SR swap with similar power and the SR weighs less... between the two the SR looks like it's more appropriate for what I'm trying to do.

SR... the lightest motor of the bunch which is a definite plus, it's built for a turbo so I can add boost within reason without worrying too much about reliability but overall I'm looking at mediocre performance unless I push the envelope above and beyond just the swap.

RB... really cool, I love inline 6 motors, RB20s wouldn't be much better than an SR, RB25s are really nice but much more expensive and difficult to swap, the power is there though, and an RB26 was just too damn expensive to make work... What really killed the RB though was the weight, the motor weighs almost twice that of an SR... that doesn't do well for my goals since I want to either drop weight or keep it about the same... adding an extra 200-300 lbs wasn't going to do me any favors in the handling department.

2JZ... I love the MKIV supra, mostly for it's motor... 4 digit HP numbers are the stuff dreams are made of, and the motor is bulletproof with lots of people rolling high mileage 2JZs in the 600hp range all day. The swap is more expensive than an SR but it's really not THAT expensive that it would put the swap out of reach. The engine is slightly lighter than an RB25, so while it's more weight than I want it at least puts it above the RB in the pecking order of consideration. I knew a guy who had done this swap recently so I called him up and picked his brain with a bunch of question... I wasn't too impressed after the conversation. The motor doesn't fit very well in the car, neither does an adequate radiator, and with twin turbos heat is a serious issue with this swap without much a solution available. He couldn't run the AC without the motor overheating, nor could he really romp on it without suffering the same problem. He said the added weight really screwed up the handling characteristics too. it looked like if I really wanted a 2JZ I would have to buy a Supra.

VQ... The relative new kid on the block... I had test drove a 350z and while I didn't like it most of my issues were with the chassis. The VQ looked like a really good fit for my swap.... power right where I wanted it from the factory, it weighed the same as the factory KA, and even better was that the weight was placed really far back which would improve the balance of the car....There is a small issue of the engine hanging really low, leaving the oil pan somewhat exposed, also I had heard that there wasn't much you could do to make NA power easily and forced induction made it unreliable. This was ok though because the factory power was about what I wanted to make to start anyway, nothing here so bad to deter me. I thought I had a winner... that is until I started looking at the details.

VQs aren't cheap... you can't touch a good VQ35DE with a 6 speed and complete harness for less than 5K unless you want to rebuilt a broken or high mileage one... or you get lucky at some junk yard. That's just the cost of the motor you can add another $2K for the swap kit and then another $1-$2K on top of that for random other crap you'll end up needing. There are some other problems too. The security system right down to the keyless entry and door locks is all integrated into the ECM, so while it would be really cool to swap in 350Z gauges and keyless ignition... that's a whole F-ton of extra work, not to mention the parts list grows substantially. That's one option, the other option is to ditch the factory ECM and get a stand-alone unit... which in turn causes you to lose a number of creature comforts... fine if you want to built a race car but that's not going to work for my goals.

It looked like it was either going to be SR or VQ, and while the VQ looked perfect the more I researched the more I realized it was just way too far out of my price range. The only way it would work would be if I got lucky and found a wrecked 350Z... I really didn't like my options.

Then someone asked the question "Why not swap in an LS1?"

I had never really thought about it before... wasn't a big Chevy V8 way too heavy? I mean I knew it would fit, I'd seen it done but I figured it would be so heavy and unbalanced that it would make an RB look light... probably would be just as complicated as the VQ as well... but I'd look into it...

The Selling Point
WOW... not only was the LS1 way lighter than I expect but the factory performance specs blew away the VQ, the transmission was known to be bullet proof, and it apparently responds really well to mods allowing you to make cheap power reliably without going turbo. Even better was the fact that it was a popular American produced motor that had been in production since 1998 so the chances of finding one cheap were pretty good, not only that but finding parts would be way easier than an RB or SR

unlike the other engines were the more I looked into it the more I cringed.. the more I looked at the LS1 the more I thought "why aren't more people swapping this... this motor is frigging PERFECT!" General Motors, knowing their enthusiast audience well built the LS1 to be easily swappable. The OEM computer actually acts like a stand alone, it's completely separate from non-motor functions and it is quite easy to re-map and re-configure. changing the ECM for use on a automatic to use on a 6-speed is as simple as flipping a bit in the configuration. using different rear-end gears? different tire size? different injectors, different cams? easily reprogrammed. Putting it in an S-chassis is as simple as re-flashing it for your setup and soldering 8 wires...

The price was even better... most people seemed to be paying between 3K and 4K for a motor with the highest price being around 5K and the lowest around 2.7K... there are 4 swap kits on the market that cost around 1.5K and you're looking at another 1-2K worth of other random parts to make it happen. The engine is really happy in the car too you can get all the amenities like cruise, and AC and the engine doesn't hang low like the VQ nor does it have any of the overheating problems of the 2JZ...

As for the weight, based on speaking with people who have done the swap and weighed the motors on the same scale: an LS1 with a T-56 6-speed weighs about 40lbs more than a factory KA with an automatic. More importantly is that the engine itself without the transmission actually weighs LESS than a KA without the transmission... meaning most of the weight in the LS1 swap is in the transmission, which means that weight balance is shifted much more towards the center of the car, and much lower than that of a KA. While that's adding weight, it's weight that can be easily cut with a few standard weight reduction mods and the balance of the car would likely be better with the LS1 anyway. Also consider that if going KA-T you're adding weight through the turbo, IC, and all that extra piping...

I'm not the kind of guy who feels the need to stay "All Nissan" or "All Japan" I am a fan of all cars no matter what country they come from, I like Japanese cars because they're the easiest to work on, and usually the cheapest to find parts for. Being able to combine the muscle of an American car with the Styling and handing characteristics of a Japanese car is my kind of project

[theimbalance]

you actually pulled the trigger, huh? Congrats for sackin' up dude.

[JSC]

when we get our respective V8s done, we should compare

yours will probably be faster, but mine should be street mod legal :-p

[RedEvil]

YEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEESSSSSS SSSSSSSSSSSSSSSS!!!!!!

[Neurowave]

oooh. this should be interesting

[twistedsymphony]

updated top post...

[sdaigle240]

damn u go nuts.....

the only part i read as it caught my eye....
VQ's are under 2k , my buddies in his 260 was 1800 w/ 31k w/ trans what price range are these ls1's

[twistedsymphony]

Originally Posted by sdaigle240

damn u go nuts.....

the only part i read as it caught my eye....
VQ's are under 2k , my buddies in his 260 was 1800 w/ 31k w/ trans what price range are these ls1's

we talking VQ35s from 350Zs or a VQ from another car... because there is an ENORMOUS price difference... the cheapest ones out of a 350Z I've seen were for around $3K and that was just the motor and completely stripped. If your friends managed to get complete swaps for those prices then they should play the lotto because they're some lucky SOBs.

You could probably find a LONG BLOCK for those prices, but you still need a harness, ECM, Accessories, Transmission, and that crap adds up fast.

I paid 2500 for the motor in the picture up top. and thats with the complete harness computer and all accessories
I still have to find a transmission and I expect to pay about another grand for that after shipping (unless I can find one local)

[twistedsymphony]

I just picked up the engine...

holy crap is that thing big...

now I need to figure out how to get it off the truck

[RedEvil]

you forgot one thing about Sr20s that their valvetrains suck and are poorly designed.

Im ready to put something in my 240 i can swap to a carburetor. hahaha