LY7 Swap - Third Generation Forum

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LY7 Swap
Tuesday, July 12, 2011 10:23 AM
Hello all. 'New to the forum. I joined to chronicle my 1996 Z-24 / LY7 build. I have acquired a 5k mile engine and plan to begin working on it within the next month. I own the equipment (machine tools, welders, etc.) and will be doing the fab work myself. I will be running the latest release of MS3 / MS3X to manage fuel, spark and VVT.

I purchased the car a couple of years ago with the intent of swapping in a 3.4 DOHC. - As time has passed, I have grown less and less fond of that idea. As mush as I love the LQ1, the LY7 is everything it isn't (lighter, VVT, more stock power, timing chain vs. belt, etc. etc.). The ability to purchase a low mile motor for small money is just icing on the cake. As far as weight goes, my 2009 LY7 weighs only 40lb more than the twin cam motor currently in the car but makes 252hp stock. I will be sure to post as soon as I get started.

Cheers

Re: LY7 Swap
Tuesday, July 12, 2011 10:39 AM
Now this is a proper unconventional swap thread. Good luck and do you have any plans for it after the swap?




its an old concept. time for something new to take the reigns. - Z yaaaa

Re: LY7 Swap
Tuesday, July 12, 2011 10:53 AM
Interesting. What are your plans for the tranny?






Re: LY7 Swap
Tuesday, July 12, 2011 11:07 AM
This is the first (maybe second when considering Series-2/3 3800V6 S/C) V6 swap worth doing. Instead of those dated boat anchors that are so famous around these parts. For starters the LY7 is a 3.6L and the power ranges from 242HP-275HP depending on models. Take note that these engines have had oiling/chain issues, so do some research on any GM updates to a fix while you have the motor out.
Good luck with transplant and keep us updated.



>>>For Sale? Clicky!<<<
-----The orginal Mr.Goodwrench on the JBO since 11/99-----

Re: LY7 Swap
Tuesday, July 12, 2011 11:30 AM
My plans are to use the car as a daily driver during bad weather. My fair weather car is a 1999 10AE Miata.

I will be running a "hybrid" Getrag 282. I say hybrid because, within the confines of the clusters, I will be using gears from a V6 unit and a FDFF (3.94 fdr) unit. My goal is to bring the ratios a little closer. As far as adapting goes, I am going to make a girdle type of adapter so that I don't add to the length of the drivetrain. If time allows, I'll make a masterplate so that I can make additional adapters in the future. The other challenge is going to be coming up with a M.T. flywheel. RIght now, I am waiting for an LY7 starter (don't have an LY7 A.T. flywheel to compare) to arrive to determine whether or not the diameter of the flywheel is the same as a standard 60degv6 flywheel.

Thanks for the heads-up on the timing chains. I have read the same thing. - My understanding is that, sometime in the 2007 model year, GM went to a smaller pitch chain and gears. If I understand correctly, this was done to address some of the problems with the earlier engines. A side benefit is that the smaller pitch chain is quieter.

Cheers
Re: LY7 Swap
Tuesday, July 12, 2011 3:06 PM
I hope to see LOTS of before, during, during and more during, and then some after pics!!!



Re: LY7 Swap
Tuesday, July 12, 2011 3:29 PM
3.6s use the eco bolt pattern on belhousing atleast looks wise they do never accually lined it up



JBO since July 30, 2001
Re: LY7 Swap
Tuesday, July 12, 2011 4:58 PM
NOTa2_4 wrote:3.6s use the eco bolt pattern on belhousing atleast looks wise they do never accually lined it up
This is exactly why I asked the question. Also, electronically this will be a considerable challenge. These engines actually share a lot more in common with the newer Ecos than with the other 60 degree V6 engines.








Re: LY7 Swap
Wednesday, July 13, 2011 11:08 AM
I don't have an ecotec bell in hand to test but, from the research I have done, they are similar looking but completely different. If I take the time to make make a master plate, I will be able to duplicate the adapter in the future. Regardless, it will require some minor machining to the Getrag bell. I'll be sure to post photos once I start on the adapter. - It'll be the first piece made.

I'm with you on the challenge involved seting up the VVT. The plan is to build static multiple scenarios in Engine Analyzer to determine the optimum advance / retard / lobe center as per RPM, etc.

I'm pretty pumped about getting started. - Right now, I am working to get the finishing touches completed on my M35 (deuce-and-a-half) truck. As soon as that's finished, things should start rolling.

Cheers
Re: LY7 Swap
Wednesday, July 13, 2011 4:09 PM
You could just ask someone to post up pictures of the stock cam tables.

Or better yet run the stock computer with hp tuners. So long as you're not boosted that computer is fine. Even with boost it doesnt look too bad. When you go to wire it up just pretend its a stand alone.


like this

Divide the numbers by 10 to get the actual angle.


Edited 1 time(s). Last edited Wednesday, July 13, 2011 4:14 PM

1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by: Kronos Performance

WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Re: LY7 Swap
Thursday, July 14, 2011 10:08 AM
@Leafy: Based on the file name of the screenshot you posted, I am assuming that those values are for the LY7. - Thanx!

Well, I got my LY7 engine home yesterday. - I had LKQ ship it to my employer since we have forklifts available. I took a few measurements to confirm those that had been given me prior to the purchase. (I'll post some photos when I get an opportunity.) Overall, it is slightly shorter than the twin cam engine that's currently in my Z-24. My best estimate is about 1/2" - 3/4" shorter. The distance from the bell surface to the outside rim of the harmonic balancer is 19.5" +/-. At the widest point (excluding exhaust manifolds), it measures 22.5" +/-. Total height from the oilpan to the top of the upper intake is 30" +/-. While in our warehouse, it was weighed while sitting in a wooden cradle on a 48" pallet. Total weight was 404lb. I have to guess that the pallet and the wooden crate weighed 70lb - 80lb. The engine is complete less starter and alternator.

Speaking of boost, I am thinking about running an Eaton M90. I just purchased a unit from a Super Coupe. 'Nice thing about the ford version is that they can be remote mounted a lot easier than the GM M90 blowers can. I'm undecided but leaning toward blown. - We'll see once I get the drivetrain dummied up and I can see what kind of room I have to work with on the front side of the oil pan.

Yesterday was a good day for getting some cool things. - I also received an oil filter adapter that I purchased. I got a used one from a CTS so that I can free up some space on the front of the engine. That high mount, self draining filter should make oil changes a little more pleasant, too.

As far as wiring goes, I'll be making my own harness to use with MegaSquirt. I was fortunate enough to get all of the connectors with the engine, though. (They were left on the sensors, injectors, etc. with wires cut at about 1".) They are new / nice enough that I will be able to extract the pins and reuse the shells and seals. I'll just need to identify them all and order the appropriate terminals from Mouser Electronics. Check out their site if you're ever in need of factory connector shells, etc.

Cheers

Re: LY7 Swap
Thursday, July 14, 2011 1:49 PM
Well I'd skip that stock PCM looking at it further. You cant adjust cam timing above 75% load (and I cant even tell you what it is) and you are thinking boost which wont be too great on that pcm. Now your choice of mega squirt, that I'd like to talk you out of. I've played with the software and such, I'm not too impressed with the data logging and a few other aspects and that, along with some hardware short comings makes me think that the new AEM EMS$ unit is the piece to get in the stand alone market But unfortunately its only 4 cylinder and less. You could get the normal EMS but thats 2 grand and thats quite a large sum of money more than the MS. The Haltech S2000 will let you run true sequential injection and coil on plug/individual coils on that car. It says it supports VVT system but doesnt exclusively list GM. If the MS supports the VVT on that engine already then it might actually be the best choice.


1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by: Kronos Performance

WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Re: LY7 Swap
Friday, July 15, 2011 3:47 AM
I'm interested in how this goes.





i find it amusing that SHOoff has nothing better to do but follow me around & be an unhelpful dick in even cross-forum. - Jon Mick
Re: LY7 Swap
Saturday, July 16, 2011 10:37 AM
I am watching this as well.


- Your not-so-local, untrained, uncertified, backyard mechanic. But my @!#$ runs
Re: LY7 Swap
Saturday, July 16, 2011 10:47 AM
Nice..

Waiting for progress. I will be watching this



Re: LY7 Swap
Saturday, July 16, 2011 7:08 PM
I'm interested to see how this goes, but using a Megasquirt system on a late model VVT DOHC V6 sounds like trouble to me. Do you plan on mechanically locking the cams?






Re: LY7 Swap
Saturday, July 16, 2011 7:24 PM
This should be cool.. I believe he said he was going to keep the VVT hence the Megasquirt since it has support.. Tuning this is going to be the hardest part of this by far. But good luck with it and keep us updated.
Re: LY7 Swap
Saturday, July 16, 2011 7:29 PM
Tuning wont be too hard for him I can get him a lot of the stock tables. He just needs to know how to convert maf tables into VE tables and how to convert GMVE into VE.


1994 Saturn SL2 Home Coming Edition: backup car
2002 Chevy Cavalier LS Sport Coupe: In a Junk Yard
1995 Mazda Miata R-package Class=STR
Sponsored by: Kronos Performance

WPI Class of '12 Mechanical Engineering
WPI SAE Risk and Sustainability Management Officer
Re: LY7 Swap
Saturday, July 16, 2011 7:30 PM
I now have my LY7 starter. I dug out a 3.4 DOHC automatic flexplate and was able to determine (fairly confident) that the LY7 uses a flywheel / flexplate that is the same O.D. as other GM 60 degree V6 engines. The main difference is the diameter of the locating snout and the use of 8 bolts vs. 6. I also dug out a Northstar crank and measured it. - It uses 8 bolts on what appears to be the same bolt circle (80mm +/-) but the snout is 26mm vs. 39mm on the LY7.

Does anyone here have a GM 60 degree V6 with that's fully assembled laying around? I would like to find out the protrusion / recess of the crank flange relative to the bell mounting surface on the back of it. I am trying to determine whether or not the LY7 is the same as every other 60 degree GM V6, in that regard. Mostly, I am trying to see if it's easier to modify an off the shelf flywheel or to pick up a ring gear and make one from scratch. Any help on the aforementioned measurement would be appreciated.

On a side note, I learned that the LY7 uses Bosch 3 injectors. - That means that the set of 2004 Cobra 39lb injectors I have (in case I end up running the Eaton M90 I purchased) will drop in without physical adaptation.


Cheers
Re: LY7 Swap
Sunday, July 17, 2011 1:25 AM
Might try asking the real technical stuff like that on 60degreev6.com Those guys really know their 660's.





i find it amusing that SHOoff has nothing better to do but follow me around & be an unhelpful dick in even cross-forum. - Jon Mick
Re: LY7 Swap
Sunday, July 17, 2011 6:07 AM
Watching this. I am interested to see where this goes





Re: LY7 Swap
Sunday, July 17, 2011 11:56 AM
Quote:

Does anyone here have a GM 60 degree V6 with that's fully assembled laying around? I would like to find out the protrusion / recess of the crank flange relative to the bell mounting surface on the back of it. I am trying to determine whether or not the LY7 is the same as every other 60 degree GM V6, in that regard. Mostly, I am trying to see if it's easier to modify an off the shelf flywheel or to pick up a ring gear and make one from scratch. Any help on the aforementioned measurement would be appreciated.
I have 3 actually, LOL. The flywheel/flexplate mounting face on the end of the crank is exactly flush with the bellhousing mounting face on the block.


Quote:

I believe he said he was going to keep the VVT hence the Megasquirt since it has support...
Interesting about MS supporting VVT. Last I knew, the method GM uses to control the cams on their VVT hadn't yet been implemented on anything like that. Guys that were running the 3500 and 3900 VVT engines with anything but the factory computer were using a mechanical cam advance locking mechanism, thereby disabling the VVT. If the MS will actually control this, it will open up a lot of options with these engines.






Re: LY7 Swap
Sunday, July 17, 2011 2:31 PM
Thank you, Mr. Quick!! That measurement helps a bunch. I have an LQ1 but it's stored overhead in pieces.

I suspected that the LY7 had more rear protrusion on the crank due to the rear seal retainer. It projects roughly .072" beyond the bell mounting surface. Comparing the LY7 starter snout protrusion and the LQ1 A.T. flywheel I have, it looks like I'll be able to use a modified 60 degree V6 M.T. flywheel. Redriling it for the much larger (bolt circle) LY7 bolt pattern should not have an adverse effect on strength. My only concern is the .072" cut I'll have to make on the back of it (to correct T.O. bearing and ring gear location). Depending on the amount of material I'll have to work with (I have a new 1990 Z-24, 3.1L M.T. flywheel coming - not received yet), I could also make a reinforcing cap that is drilled with both bolt patterns and doweled on the smaller one. The fact that the LQ1 flywheel tapers away from the crank flange (roughly .200") helps a bunch. - I'll only need to remove material from the flange area. - Otherwise, I would either have to deal with clearance issues (seal retainer) of thin the whole thing.

I was trying to confirm the capacity of the LY7 stock injectors (Bosch 0280156300) and the 4.6L Cobra injectors (Bosch 0280156127) and located an interesting chart at http://www.usrallyteam.com/content/products/injector/Bosch_Injector_data.xls .

Here are a couple of writeups on VVT. - One is a general explanation from Delphi regarding their cam phasers ( http://delphi.com/shared/pdf/ppd/pwrtrn/gas_vlvvcp.pdf ). The other is a MegaSquirt / BMW VANOS writeup from March ( http://delphi.com/shared/pdf/ppd/pwrtrn/gas_vlvvcp.pdf )

Cheers
Re: LY7 Swap
Sunday, July 17, 2011 2:34 PM
FYI the correct link for the MegaSquirt writeup is http://www.msextra.com/doc/ms3/vvt.html . - Sorry
Re: LY7 Swap
Sunday, July 17, 2011 6:21 PM
does that engine use a 8 bolt flywheel if so look at the LSJ or camero 3800 flywheel

camero one is weighted on the flywheel so that may cahnge things are you gonna go auto or 5spd have you confirmed the bellhousing from an ecotec will fit or not



JBO since July 30, 2001
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