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Nov. 22, 2011 2:21 p.m. mw HalfDork

I know there has been a lot of talk about the gm 4.8 lately after the hot rod articles etc. I've decided I want one for my rod project. In general, I'm v8 and electrically retarded. So my question is, When I'm shopping for one, can anyone give me a list of things that I should make sure are present when I buy one. I want one with an auto and want to make sure I'm getting everything I need for it to run on it's own.

Anyone willing to baby me through this? I have tons of clearance since there are no hood or fenders. As long as they aren't required for the engine to run, I don't need cats.
Nov. 22, 2011 2:36 p.m. Bobzilla SuperDork

Best bet would be to get a complete take out with auto, harness and ecu. That makes it really easy.
Nov. 22, 2011 2:47 p.m. Bobzilla SuperDork

Here's one: http://www.ebay.com/itm/Chevy-4-8-LS-Engine-Complete-Stand-Alone-EFI-Harness-NO-Tr...

also, 1999-2003 were still cable operated throttle bodies. 2004-up are all Throttle By Wire. So if you get a newer engine, you'll either need the acelerator pedal assembly to go with it or retrofit it.

This one is cheaper and looks to have the harness but no accessories or ECU. http://www.ebay.com/itm/1999-SIERRA-SILVERADO-1500-TRUCK-4-8L-ENGINE-LOW-MILES-/33...
Nov. 22, 2011 6:45 p.m. mw HalfDork

Yeah, There's a local guy who says he has one for an 06 that's complete minus the cats. I was just curious what complete means so that I know I'm not missing anything. It's good to know I'd need the pedal assembly. Also, will it matter to me if it's 2wd or 4wd? Is transmission the same or is the transfer case part of the tranny?
Nov. 22, 2011 6:49 p.m. TIGMOTORSPORTS Reader

I understand Lokar is now selling a pedal assembly for the electronic version. http://www.lokar.com/product-pgs/new-products/newproduct-pgs/drive-by-wire.html
Nov. 22, 2011 7:53 p.m. ValuePack Dork

mw wrote:

Also, will it matter to me if it's 2wd or 4wd? Is transmission the same or is the transfer case part of the tranny?

As near as I can recollect, you may need to swap tailhousings for a 2wd application. I can't remember if the output shaft is the same between the two trannys.
Nov. 22, 2011 8:49 p.m. BoostedBrandon HalfDork

You can run LSx engines with carbs ya know....
Nov. 22, 2011 9:22 p.m. Taiden Dork

I wish I could convince myself that the 4l60e is an acceptable transmission for the e30 daily
Nov. 22, 2011 11:54 p.m. Vigo SuperDork

Torque makes autos livable. Maybe even fun depending on who you ask.
Nov. 23, 2011 7:32 a.m. Bobzilla SuperDork

^ Agreed.... the 4.8 in a smaller, lighter package with a proper tune allowing it to breathe and an LS6 intake would make a GREAT screamer. 7k upshifts.... and torque curve as broad as the great plains... I could live with that in an e30.
Nov. 23, 2011 7:49 a.m. njansenv HalfDork

You can do pretty neat things with the 4L60e's, involving manual shift inputs etc. :)
Nov. 23, 2011 8:03 a.m. Ranger50 Dork

njansenv wrote:

You can do pretty neat things with the 4L60e's, involving manual shift inputs etc. :)

Yes you can, but until you spend the 900 bones on a new planetary to fix the first gear drop, and fix the powerflow problems, it is still only going to live until about 800hp. Plus the manual VB kit is "only" $300, shop cost...... For the cost of "fixing" a 4L60 to live, you can build a 4L80. Hell, I can just about build an "OD" Proflite for what a 4L60 costs......
Nov. 23, 2011 8:36 a.m. patgizz SuperDork

mike, with motor mount adapter plates an ls engine drops right in on those new poly mounts, trans crossmember will need moved back and floor will need a bigger hump unless you run the th350.

look to lkq, there is one by me in akron, i'll pick one up and hold if you need me to
Nov. 23, 2011 8:42 a.m. novaderrik Dork

BoostedBrandon wrote:

You can run LSx engines with carbs ya know....

not only that, but GM sells a front cover that allows you to use any distributor that fits a 5.0 Ford. they actually look like a 5.0 when they have a carb and a distributor.. you could really screw with people and run a mid 70's Duraspark ignition on one..
Nov. 23, 2011 8:42 a.m. Taiden Dork

Whenever I search for 4l60e it's either websites selling multiple thousand dollar built transmissions or youtube videos of people accelerating in stock 5.3L trucks. Are there any good resources out there to learn about what's possible with these transmissions, or should I just start a 'learn me' thread?
Nov. 23, 2011 8:59 a.m. Ranger50 Dork

Taiden wrote:

Are there any good resources out there to learn about what's possible with these transmissions, or should I just start a 'learn me' thread?

Besides what I have learned in 25yrs watching my dad rebuild transmissions and reading EVERY transmission article published, www.clickclickracing.com, mostly AOD's but there is a nice 700/4L60 article by performabuilt, and the Transmission forums on www.yellowbullet.com and www.ls1tech.com are my goto's for fairly current info.

I also get a lot of information from the trade mags published by ATRA and ATSG. Those are more geared to one-step-above-stock rebuilds, but it clearly shows the weaknesses the factory ignores.
Nov. 23, 2011 12:17 p.m. 2002maniac HalfDork

Ranger50 wrote:

Yes you can, but until you spend the 900 bones on a new planetary to fix the first gear drop, and fix the powerflow problems, it is still only going to live until about 800hp. Plus the manual VB kit is "only" $300, shop cost...... For the cost of "fixing" a 4L60 to live, you can build a 4L80. Hell, I can just about build an "OD" Proflite for what a 4L60 costs......

I think 800hp powerholding should be ok for any streetable 4.8

My main concern would be weight. According to google, the 4L60 weighs over 160lbs! I think in a small, traction limited car a T5 would be the way to go.