1 2
Somebeach (Forum Supporter)
Somebeach (Forum Supporter) HalfDork
1/7/21 3:02 p.m.

Just a mental exercise here. If doing a swap and those were your two categories to choose from what would you choose? 
 

Seems fairly similar as far as power levels go. People seem to quote NA with not many mods around 200hp from either a LE5 or the K24.  
 

Turbo a LSJ or a K24 both seem like great platforms. 
 

Seems like both can be set up "stand alone" pretty easily. 
 

So what would you choose and why? 
 

Would the car your swapping into be a FWD or RWD make a difference? 

fatallightning
fatallightning Reader
1/7/21 3:16 p.m.

K series just seems to me, much more widespread aftermarket wise. They make trans adapters for almost everything you'd actually want. Tuning options are endless. 

Robbie (Forum Supporter)
Robbie (Forum Supporter) GRM+ Memberand MegaDork
1/7/21 3:21 p.m.

good question!

both can be found with a factory transverse transmission with a helical LSD! (pretty rare for both though)

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
1/7/21 3:22 p.m.

I have limited experience with the Ecotec in an Atom (as well as a Honda something in an Atom) and the GM engine was just bland. I would be tempted to go K series simply for character if this is not a competition car.

Somebeach (Forum Supporter)
Somebeach (Forum Supporter) HalfDork
1/7/21 3:33 p.m.

In reply to Keith Tanner :

Character being some undefinable aspects? Ie just like it better.

Or something specific? 

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
1/7/21 3:37 p.m.

The Ecotec didn't make interesting noises and the power delivery was workmanlike but not interesting. No feel of eagerness from the engine as the revs climbed. It just kinda blared away and didn't egg you on. Does that make sense? I feel the same way about the MZR/Duratec engine in the NC Miata.

The Honda engine in that application had a resonance that made my eyeballs unfocus, but that's mostly because the air intake on an Atom is basically at your ear. It also had a terrible, terrible gearchage that was less precise than my Vanagon, but that's a fault of the implementation. Meanwhile, it was responsive and tuneful and loved to rev.

RevolverRob
RevolverRob New Reader
1/7/21 3:56 p.m.

My not so humble, highly biased, opinion - the Ecotec and the cars they come in are hunks of trash best suited for use as boat anchors and artificial reefs. The transmissions are vague with a throw the width of Tennessee. I'd rather walk than own another Ecotec equipped car. Which is not a popular opinion, I know.

Slight backstory: My wife purchased a lightly used 2004 Saturn Ion in ~2008, it had <35k miles on it. That car was the biggest hunk of steaming pile of E36 M3 I've ever had the misfortune of wrenching on. When purchased it had excellent maintenance records and we maintained it carefully, full synthetic its whole life, 4000 miles between changes, etc. The car spun a bearing at 135k miles driving down the highway, simply lost oil pressure and bit the dust at 70mph in 5th gear. I've never been so happy to have a car blow up.

Prior to that, I'd had to replace all the injectors, two O2 sensors, a water pump, valve cover gasket, a throttle position sensor, and an a/c compressor. Then there were the platform specific problems, GMs notoriously fault anti-theft ignition switches...so anti-theft the car wouldn't start on days below 35-degrees...I had to replace the radiator, both electric fan motors, multiple pieces of rubber trim split and cracked before the car was 5-years old. The car ATE front struts, despite opting for quality replacement parts (Bilstein), I couldn't get 35k out of a set of front struts. Electric mirror motors both died, sunroof leaked and caused water damage on the inside of the car, and an exhaust heat shield simply broke and flew off one day driving around town. That car was the end of owning or even considering new GM Products for me. If I ever own another GM vehicle it will have been made before I was born.

There are probably good Ecotecs out there. I will never know, because my singular experience was so awful, I've written the entirety of them off for consideration to power anything.

Thus for me, the K-Series is the answer. So much so, it's what I decided on for my project. I wanted to explore the MZR as an option, I enjoyed the 2.3 DISI Turbo I had in my MS3, but it's simply not a viable engine for an LBC. The K-series has so many gearbox adapters, easy power, I've had friends in the industry refer to them as, "The LS of 4-cylinders/Imports." And I think they're right on.

Peabody
Peabody UltimaDork
1/7/21 4:08 p.m.

Depends on what your priorities are.

The K24 can make more power more easily.

The Eco is a lot cheaper and the stock computer is very good and easy to work with.

Keith Tanner said:

The Ecotec didn't make interesting noises and the power delivery was workmanlike but not interesting. No feel of eagerness from the engine as the revs climbed. It just kinda blared away and didn't egg you on.

Tune

Keith Tanner
Keith Tanner GRM+ Memberand MegaDork
1/7/21 4:14 p.m.
Peabody said:

Depends on what your priorities are.

The K24 can make more power more easily.

The Eco is a lot cheaper and the stock computer is very good and easy to work with.

Keith Tanner said:

The Ecotec didn't make interesting noises and the power delivery was workmanlike but not interesting. No feel of eagerness from the engine as the revs climbed. It just kinda blared away and didn't egg you on.

Tune

Like I said, limited exposure. But if I were planning my own project, I'd take the engine that I know is fun instead of the engine that might be fun if I get the right tune in it. I personally believe that OE engine calibrators are better than 99.5% of the ones working in the aftermarket.

codrus (Forum Supporter)
codrus (Forum Supporter) GRM+ Memberand UberDork
1/7/21 4:24 p.m.

If the question is in a vacuum regarding other considerations (cost, availability, packaging, etc), then Honda.  Everything I've seen says that the Honda heads flow so much better than almost anything else out there.

 

Peabody
Peabody UltimaDork
1/7/21 4:26 p.m.

Maybe 100% but they have different priorities.

I've driven them before and after tune and I would describe the before the way you did. The average Eco owner doesn't want his Malibu to exhibit any of the qualities you were looking for.

kb58
kb58 SuperDork
1/7/21 5:02 p.m.

Have a seat and get a cup of coffee, this is one of my epic posts:

It all depends upon what kind of power you want out of either engine, though my comments come from a K24 background.

Stock: I completely agree that the K24 is the right choice

200 hp normally-aspirated (NA): Sure, no problem, $$$-$$$$

250hp NA: Needs internal mods like valve springs and cams, $,$$$. Going to be loud due to the required low-restriction exhaust and high rpm.

300hp NA: About the realistic maximum, $$,$$$, and very very loud due to high rpm and high compression. Will need race gas/E85. Total rebuild with better parts. Has to rev to about 10K to reach that power.

Turbo: No point until you get above maybe 250 hp.

300-350: "Some say" you just add a turbo and go, and that it'll be dead reliable. What's always left out is a detailed explanation of exactly how it's used. Street, probably fine. Drag strip, who knows. Track days, hard to say, depends a lot on cooling.

400-500: "Some say" same as above, just crank up the boost. There are urban legends of people making a lot of power on a stock block, but again, no other data than it did it, but no word on for how long and under what circumstances. At this point it's wise to replace everything with better parts and improve the cooling system in a big way.

Above that: a full build isn't an option. If you have a shop do the work, it'll be $$,$$$

If you're entertaining keeping the OEM transaxle, it's an awesome transmission as-designed, but add power and its reliability takes a nose dive. The good news is that there are options out there, but figure mid $$$$

My story:

In short (hah!) I built a turbo K24 capable of "800hp" but kept the boost low so it never ran more than maybe 400 hp. Additionally, as-built, the rev limit was 9300 rpm, so I shifted at 8000. At trackdays it was run on E85 for insurance, and it was perfectly fine until it wasn't, with a connection rod exited stage left. No one had a good theory about what happened, as due to the damage, it was near impossible to tell what failed first. The bearings were in perfect condition, so no oil issues (was dry-sumped). Half the experts said that the pistons looked like they'd been hot. The other experts said that wasn't the problem. The only possible hint was found a year later when the new engine was being tuned, and the tuner asked why ignition timing was so retarded - and locked. I had no idea, and whether that had something to do with the failure, I don't know.

BUT, I did catch up to the Porsche GT3 on track... priceless, until I coasted to the side of the track and he lapped me over and over... I'm sorry, what was this thread about? Oh, yeah, my point is that if you turbo an engine, it needs to be built really well, with no shortcuts, and that costs money.

My incident track video The funny thing is it was such a subtle failure that I thought that one spark plug had failed. There were no flames, no "kaboom", no locking up. The engine kept running, seemingly fine. It wasn't until I slowed I could hear something and there was a wisp of smoke. Sigh.

obsolete
obsolete GRM+ Memberand New Reader
1/7/21 5:55 p.m.

K24 vs. LE5 were the final two candidates for my swap project, after eliminating several others. I ended up choosing the Ecotec. I did a whole decision matrix, a lot of which was specific to my car, but in summary, it came down to:

  • Stock block horsepower, both with and without a turbo, seems to be about the same between the two. 200HP out of the box with better breathing and a tune, 400HP with a turbo and reasonable supporting mods before you start breaking major parts.
  • Both engines are right in the sweet spot of junkyard availability (about 15 years old).
  • The Ecotec oil pan isn't exactly front-sump (more like mid-sump), but it's farther forward than the K oil pans I've seen. For a rear-steer RWD car, having some room for the crossmember and steering to live between the sump and the bellhousing makes life easier.
  • HP Tuners and Hondata Kpro seem pretty comparable for tuning, but I already own HP Tuners, so there's $700 saved.
  • Multiple RWD transmission adapter options exist for both, but I couldn't find an option for the K at the time that didn't mean getting stuck with a small clutch. Since then, Kpower has come out with an adapter setup to use a BMW E46 clutch, which is pretty decent, but I don't think the BMW trans would fit my floorpan.

As for the uninspiring sound/character of the Ecotecs, I think a lot of it comes down to how small the exhaust ports are. GM optimized them for velocity at their target power level. All about torque and efficiency. I think there's some potential in opening the exhaust side of the head up for a performance application, but I don't have any data to back that up besides looking at the exhaust ports on mine and saying "wow, these are tiny".

Kreb (Forum Supporter)
Kreb (Forum Supporter) GRM+ Memberand UberDork
1/7/21 6:22 p.m.
Peabody said:

The Eco is a lot cheaper and the stock computer is very good and easy to work with.

Tune

Is the Eco a lot cheaper anymore? Seems like Ks are such old news that they can be had inexpensively at this point.

Somebeach (Forum Supporter)
Somebeach (Forum Supporter) HalfDork
1/7/21 6:33 p.m.

In reply to Kreb (Forum Supporter) :

You can find the Saab 9-3 turbo ecotects for 250-450 on carpart.com

Somebeach (Forum Supporter)
Somebeach (Forum Supporter) HalfDork
1/7/21 6:34 p.m.

In reply to kb58 :

Thanks. Good info there. Did you just go with another of the same engine and build or change it up?

Somebeach (Forum Supporter)
Somebeach (Forum Supporter) HalfDork
1/7/21 6:36 p.m.

In reply to obsolete :

good info thanks. 

RevolverRob
RevolverRob New Reader
1/7/21 6:59 p.m.

I assume that an HP Tuner will allow you to tune the drive-by-wire system response rate? Throttle response is always terrible in the stock Ecotecs I've driven (not just the one we owned, which was also abysmal). By contrast the K-series drive-by-wire throttle response seems much more instant than the Ecotec. If not, one has to figure out a throttle cable conversion setup could be easy, I don't know. Just worth bearing in mind if considering between these two.

Since this is a bit of a thought exercise - if this is going into a FWD car using the GM or Honda transaxle, the Honda is vastly superior in terms of shifter feel and throw. Even with a short shifter the GM transaxles have a vagary to the gear positions that can result in missed 2-3 shifts. That said, GM has better gearing for road use, Hondas, at least where you'll be sourcing the 200hp K2xs from are typically geared too low (numerically high), I find them 'buzzy'. The Ecotec is not buzzy at speed. I'll give them that, they're easy to drive on the freeway.

 

Peabody
Peabody UltimaDork
1/7/21 7:04 p.m.

In reply to Kreb (Forum Supporter) :

Last I asked a LE5 was $300 with computer and harness

 

kb58
kb58 SuperDork
1/7/21 7:55 p.m.
Somebeach (Forum Supporter) said:

In reply to kb58 :

Thanks. Good info there. Did you just go with another of the same engine and build or change it up?

Had another built, and was able to salvage the head, turbo, and exhaust from the first engine. The "good" thing about a connecting rod giving up is that the piston ends up at the bottom of the cylinder and the head was untouched. Also, no parts went through the turbine. The other parts I left to the builder's discretion, because I had supplied the parts I wanted in the first build, and was feeling far less cocky the second time around...

BTW, regarding ECUs, I originally went with K-Pro, but what drove me nuts was that it couldn't do closed-loop boost limiting, which made no sense because they had everything necessary to do so. Anyway, I "think" they have the ability now, but that was after I gave up on them and switched to an AEM Infinity ECU.

What I forgot to say above was that if I was doing it all over again, I'd think long and hard about just putting in a drivetrain that's already turbo'd, and turning it up slightly, and leaving it otherwise alone! That said, and as mentioned above, the Honda does have the enormous advantage of a huge aftermarket. You want it, it's out there, it just costs money.

ProDarwin
ProDarwin MegaDork
1/7/21 8:07 p.m.

If I was on a very tight budget, Ecotec.  Esp. RWD because there are factory options for this.  Also, the L61 and LE5 are appliance motors.  An LNF or LSJ might have a lot more character.  Also can be found mated to a 6spd with a torsen (Fwd).  The LNF and LSJ make pretty respectable power from the factory.  The LNF even has a tune that was warrantied that put out ~315hp IIRC.

If I were spending $$ (like buying a swap kit) I might K-swap depending on the car.  That path is well traveled so there is likely more support.  

wspohn
wspohn SuperDork
1/8/21 10:26 a.m.

If limited to the LE5 I would opt for the Honda even though I own a Solstice GXP.  The naturally aspirated Ecotec is a reliable engine that only make a small improvement with tuning - a handful of bhp (like 5-7).  The tunes basically remedy some minor drivability foibles and add a few bhp up high where you rarely drive them.

Now if you were talking LNF, the sky is the limit (and also the space you have to accommodate a turbo).  Get the old Visa card out and place an order for the parts to build a 500 bhp LNF.

The LSJ was mentioned.  Also not the answer to ultimate power, but that supercharger sitting on it sure does look sweet!

 

obsolete
obsolete GRM+ Memberand New Reader
1/8/21 1:37 p.m.

Couple other things I thought of:

  • Both the K and the Ecotec have two-piece blocks that are split at the crank centerline, which does away with the concept of individual main bearing caps. The main bearings are sandwiched between the two block halves, with the lower half acting like a one-piece main girdle. Some of the articles I've read online raving about the K engine credit its strength to this design feature, but the K is not the only I4 built this way.
  • The Ecotec has its balance shafts up high, above the crank, whereas the K's balance shafts are down low in the oil pump module, between the crank and the sump. If you are keeping them for some reason, the low mounting position of the K's balance shafts supposedly increases oil aeration at high RPM. If you're spending a lot of time at high RPM, you should probably just eliminate them anyway, right? For what it's worth, the Gen 3 Ecotec engine (LTG, LCV, etc.) changed to a low-mounted balance shaft design, so there must be some advantages to doing it this way (manufacturing cost/efficiency, narrower block, lower CG).
buzzboy
buzzboy Dork
1/8/21 4:41 p.m.

Neither is easy(or possible?) to fit in a rear sump application as much as I'd like to K24 my BMW. However, there is a K to S5-320 adapter so that's the way I'm going as that's my favorite transmission ever.

obsolete
obsolete GRM+ Memberand New Reader
1/8/21 5:11 p.m.

In reply to buzzboy :

Which BMW? I took a look at the KPower E30 kit and their custom pan is very front-sump. That would actually be a great pan for my car if I wasn't already headed down the Ecotec path (and I wanted to pay Kpower prices).

1 2
Our Preferred Partners
Cb3LkYEEWG3UKsIwPxM9hXgNv2rv4JOnskoLPY4lsOzBFdwMULC5b71jLpzd33Ix