exninja

iTrader: (1)

I thought it would be nice to have a list of people who have completed an LDK/LHU swap so that we could exchange info or ideas about it. I'll list the people here and date that it was done. Feel free to leave your story about why you did it and whatever other details you want.

Updated 12/2/14

1. emecham 10/2014
2. footballplaya3k 7/2014
3. ctn2mb 7/2013 (sold)
4. Taintedred07
5. Slitterel
6. crashher0

exninja

iTrader: (1)

My story is that my engine got the porous block. The dealership told GM that it was somehow due to my negligence (they didn't ever tell me why so don't ask) so I was on my own to fix it. I got the longblock sans turbo from ZZP. Everything is still stock.

I'm also curious about if anyone else has or hasn't tuned after the swap. I had thought that I'd be ok without a tune, but in my last thread it looks like I may need to at least tweak the idle.

footballplaya3k

iTrader: (1)

I lost compression in cylinder 4 so I bought the whole new deal with stock turbo from ZZP. I'm running the same Trifecta 23psi tune with full bolt ons. The motor has just over 4k miles since it was installed in July.

ctn2mb

iTrader: (2)

I had ZZP do the swap on my old Cobalt that someone else on the forum owns. It was done in June 2013. As far as I know no problems with it.

JapEatr

iTrader: (9)

Taintedred07
Slitterel

crashher0

iTrader: (2)

My LDK experience is as followed:
Balance chain stretched and snapped (for those who aren't aware or new: this runs the water pump). Didn't get any warning lights of overheating until after pistons 1&4 went pop. #1 had sleeve damage way worse than #4.

Bought a long block (turboless) LDK from ZZP along with 82# springs/titanium retainers that zzp installed for me. I also tied in a S256et turbo kit and upgraded intake cam while the car was engine-less.Dropped the combo in early to mid July 2014 and broke the turbo and new clutch in for about 2k miles.

While setting up a tune date zzp informed me these "500hp rated engines" were bending rods at 400crank horse. So we safe tuned it at 341whp.

So far I have about 4k miles on the setup, was an easy swap all in all. I am currently working on saving to build the engine. How is everyone else taking the news of soft rods?

exninja

iTrader: (1)

I haven't really worried about it because I don't have any high HP plans for it.

However, I am curious because it looks like the rods from the LHU are also in the 2010 LNF's: 12638832 - Genuine GM ROD, Engine Piston BUT it's a different PN than the 2008-2009 LNF's so what's the difference?

Terminator2

That would kill me. A S-256 only 341 whp which is less than a K04 on E-85 or meth.

taintedred07

iTrader: (1)

My story is my engine went boom on the way to get my cobalt dialed in on the zfr in the middle of no where on an onramp at 3am.

Now I've got a 2.1 and 4.45 swap and goodies, just gotta get a downpipe, wastegate, mbc to put my new turbo on.

crashher0

iTrader: (2)

emecham: I honestly couldn't tell you the difference to a T other than the LDK are supposidly powder treated cast. (Cheap)

You have no idea... ZZPs site clearly said engine is rated for 500whp which is why I didn't build a block. I expected at least 400+whp with the 256 but being my only car I was forced to stay safe till I can afford to have another car to get to work in and can build my block myself.

Edit: I also didn't go for E-blend at the time of buying everything because I lived in the middle of no where that had one E station not exactly close to my work/living. I'm on 93oct right now and when tuning the stock LDK injectors were acting funny.

exninja

iTrader: (1)

Then it sounds like I should hang on to my rods in case I ever do decide to go higher HP. The price difference btwn the two PN's would reflect a cheaper material in the LDK rods. I wasn't going to just go by that since there are many factors in part prices, but it wouldn't surprise me. If the rod is good enough for the rated HP + safety factor then GM wouldn't care one bit. Until of course some QC problem got through and bit them in the butt again. Not that I'd know anything about that...

crashher0

iTrader: (2)

Does anyone know if the LHU in the regal and saab 9-5 has the same A2NFT/A20NHT block?

I was considering buying a full LHU out of a wrecked Regal or 9-5 and stripping the engine down selling off parts and using the block as the base for a LDK built engine. Everywhere I look they say "LHU" but no one gives block stamped numbers.

You can buy a full engine out of those cars at the same price as a ZZP LDK short block. Make some money back selling off the head and other parts and put that money back into forged internals, new head and cams, injectors and you would have a pretty stout engine at a fraction of the cost.

blueLNFftw

iTrader: (16)

Yes. Only difference is the LHU is flex fuel

crashher0

iTrader: (2)

Well hell I am going shopping for a rear ended regal motor then, part it out and build that sucker with parts in my spare time instead of forking out the same price for a zzp short block that will need re built anyways.

exninja

iTrader: (1)

Anyone have an issue where the car cranks but doesn't start sometimes? I'm trying to deal with it and I have a few more details here: https://www.cobaltss.net/forums/2-0l...-level-314254/. I didn't have the issue before the swap...

crashher0

iTrader: (2)

how fast do you stick the key in and start cranking it over? I stick the key in to the on but not cranking and let the pump run for a sec or two then push it the last little and start cranking.

exninja

iTrader: (1)

I never thought of doing that. I've just done the "bump start" thing, and I started holding the key till it started but it happened when I did that too. Does the pump not prime until the key goes in? In our VW the pump primes when you open the driver's door which is nice...I should know better than to expect that in a GM product

I'll pause a couple seconds from now on in ON.

crashher0

iTrader: (2)

I am not saying its going to be a garuntee fix for your problem but give the fuel pump a second to prime. If you turn everything off (Air, radio) you can hear it prime when you click the key to on but not cranking. wait till its done (1-2 sec) then give it the go ahead to crank.

My 95 Camaro was notorious for this, It wouldn't start till it was properly primed. Not saying this car is the same set up as a 90s model Camaro but I have always been told no matter what car you giver it a few seconds to collect itself even powered down electronics in the car to regain power/reset/go through their warmup.

Is it safe to assume your the kind of guy that just goes ***** deep first thrust no foreplay?

exninja

iTrader: (1)

I'm going to let that one go...

Yeah, it certainly wouldn't hurt. If that's the fix I can live with it. I've never had the issue before so it wouldn't surprise me if it's not the cure, but you're right that it's good practice. I've never really thought of it.

exninja

iTrader: (1)

That was quick. Started in limp mode coming home from work.

exninja

iTrader: (1)

I'll head back to my other thread with updates for this issue. I don't want to clutter this one.

jimbos'ss

iTrader: (2)

The heads on the regal/saab lhu are different. On the exhaust cam is a cam driven vacuum pump for the brake booster. The injectors are different as well. There is a sensor installed in the oil pan. The valve cover is different and so are the PCV lines. Other than that it looks to be a direct swap so far. I'm right in the middle of mine. I'll let you know if anything else is different or needs to be changed for swapping into a cobalt.

63 Nova SS

iTrader: (3)

I've always wondered if the 08-09 lnf rods can spin up to 7200 stock, and I haven't heard of them failing, why spend the money on aftermarket rods to spin the same rpm? Couldn't you just swap to forged pistons and leave the stock crank and rods alone? Maybe it's insurance for the heavier forged Pistons.

sixgear

I have a long block ordered so I am a little over a week behind you, you blaze the trail and let us future swappers know what you encountered and needed to complete the job. I know I will need intake and exhaust manifold gaskets but not sure of what else.

exninja

iTrader: (1)

Did you order from zzp? If so, it'll come with intake and exhaust manifold gaskets