lq4 or lq9 engine in a 1970 lemans
 

guys iam a rookie here. i have a 1970 lemans that i have most of the body work done and iam looking to put a lq engine in it. at my old age iam not familar with any of the later gm engines but looking at salvage yards it looks like you can get a pull out lq4 or lq9 with the ecm for about 2000 .. my son thinks a lq4 with l92 heads . but would a lq9 be better? i dont know what the l92 heads would cost but why not just port the lq9 heads? i would like to get to about 450 rwhp.i can do most of the mechanical work but the electronics scare me. any opinions would be appreciated.. thanks chuck

The LQ4 or the LQ9 are both excellent choices. From all I have read, 450 rwhp should be easy to achieve. You can probably reach that with the stock heads ported but your son is right about the L92/LS3 heads. They can be had from GM for under a grand for the set and they are supposed to really move the air. If you do change the heads to the L92/LS3 type you will also need to upgrade to a intake that will match the heads like the LS3 intake. Add a performance cam and you have a really nice engine.
The main difference between the LQ4 and LQ9 is the pistons and the effect they have on the compression ratio. The LQ4 has dished pistons and the LQ9 has flat top pistons so the LQ9 has higher compression. They are both 6.0 liters and both have a 4 inch bore. The stroke is also the same.
Either of these engines will serve your purpose. The LQ4 is normally less expensive as it was more common. If my memory serves me the 1999 and 2000 years had some difference in the crankshaft length at the flywheel and had cast iron heads so I would look for 2001-2006 years. There will be a letter U in the VIN of a LQ4 powered truck and a letter N in the VIN of an LQ9 powered truck.
Don't let the wiring stop you. There is a wealth of info on the web in the form of videos and forums that are specific to these gen 3 and 4 engines. There are many companies that sell complete harnesses.
I am not sure where you live but 2000 dollars seems steep for a LQ engine. There are other newer 6.0 engines out that will cost less than 2 grand where I live. Try car-part.com too.
Good luck with your choice. Just buy some books and start reading. There is a lot to these conversions but it is well within most guys abilities if he is a hot rodder.

Paul

actually i think a L92 looks better >)

after looking at car-parts.com i found a l92 nearby. it has a fire damaged intake. i would like to replace it with a pass car intake. would a ls3 intake be the way to go and also will the oil pan on a l92 work on my a body 1970 pontiac lemans?

Yes a car ls3 or l76 intake will work with the l92, they all have the rectangular ports. The l92 oil pan will not work. Mast, holley, canton, moroso, autokraft, or a modified f-body pan is what you would need. People will tell you you can use the GM "muscle car" pan but don't it will hang below your crossmember and be subject to damage.

still reading and looking, getting closer , thanks for info

I swapped an LQ4 into my 96 Chevy pickup(i have pics) all i did was install a Cold air and headers it dynoed at 297 at the wheels. I drive it daily you will be extremely i would put one in my 72 however the swap gets pricey during the nickel and dime portion of it( they always do). i would do the LQ4 again and upgrade from there.

if i put a gm 400 tranny on a l92 can i get a wiring setup and ecm that would allow me to use this setup. i see there is a site .speartech.

http://www.ebay.com/itm/CHEVY-700R4-...item3cc1071db2 will this fit and work with a l92

Yes people do run both the th400 and the 700r4. I know there is some issues with the 700r4 having a TV cable and needing something to make that work. I'm not sure what parts are needed though.

The company in that ebay link isn't very reputable if I remember correctly. I think they have changed their names multiple times and don't offer a quality product. I may be wrong but I would do some digging on them first.

Speartech can put together any harness combination that you would want. I used him for my computers for both the engine and trans.

thanks for the warning, iam going to put off for awhle on a tranny..i just picked up a l92 with 36000 miles ..

Great! Here is a link to my swap that I profiled on a different board. Lots of info can be found on that site.

http://ls1tech.com/forums/conversion...-swap-vvt.html

some bad news and some good news, the l92 with 36000 is scrap. they say buyer beware is true, when i pulled the intake i saw rust on the valves so i pulled the heads and found the cylinders rusted. when checking i found the liners are cast with the block so no boring. dont know how this could of happened but the caddy it came out was on fire... the good news is i got a l99 from a 2010 camaro with 14000 miles ...it came with all accesories and sensors even has the belts . its a take out to be replaced with a ls7..

took the l92 back to the salvage yard and got a full refund. i pulled the plugs from the l99 and they are good, put some oil in cyls and turned engine over and sealed up all holes with baggies and tape for now.. time know to find a tranny, i dont know what tranny comes with a 2010 camaro ss but it looks like a bunch will work. i have a t350 but dont know if it could be built and be used with a ecm engine with 400 hp

Great news!

That L99 has VVT (variable valve timing) just like the LY6 that I put in mine. The L92 had it as well.

Did you get the wire harness and computers?

You can run any f-body 6 speed (T-56) or the new Camaro 6 speed (TR6060) for a manual

Automatics that engine would have had are a 6l80e or 6l90e 6 speed auto. That is a big trans and to run it you need to highly modify your transmission tunnel.

If you wanted to get a 4l80e all you need to do is swap the flywheel.

thanks for the info. i did not get any wiring or ecm.. i did get the ac compresor,alternator,power steering with all of the belts still on. on the 4180 tranny do i need a tranny comp?

Yes you would need a computer for the 4l80e. There are some aftermarket controller options but those are mainly meant for people who put the new overdrive trans on a non electronic type engine.

ffgto you say i would need a different flywheel, would i have to get it from a gm dealer? also what convertor would i need if i go with a 4180..i would like to stay with a auto tranny..

Here are the GM part numbers for what you need to get the 4l80e to mate up.

Spacer - 12563532
Bolts - 19257940
Flexplate - 12621399

Also be sure to check around on this number Flexplate - 12621399 That number was a "kit" which included the spacer and the bolts but GM just changed it a few months ago. If you are able to find a dealer that has this on the shelf with the bolts and spacer it will be cheaper then having to buy everything separately. I got lucky when I got mine the local GM truck dealer had one on the shelf that still had everything included. He said he didn't even realize he had this on their shelf and the amount of dust on the box proved it!

I use the website gmpartscenter.net sometimes for larger parts orders. The prices are much cheaper then your local dealer and shipping is a flat $7.99. Shipping does take about 7-10 business days though...

Here is a link for the ARP bolts you would want for the flexplate to converter. Stock GM ones are weak and cost twice as much.
http://www.summitracing.com/parts/ARP-230-7305/

I didn't put a higher stall converter in mine when I installed the trans and I wish I did. I didn't want to spend $800 at the time though for it. I spoke with Circle D and they recommended a 3000-3200 stall for mine. You should contact some of the converter manufacturers and see what they recommend, circle D, Yank, FTI.

ffgto iam still looking at tranny options ..http://www.cpttransmission.com/2004R_trans_400hp.htm i dont know if this link will open, my son says iam computer illerate..i keep telling him its my age ..