LSX G-body Swap Write Up

[85GPLef41]

Okay, I'm jumping right into the fire. Has anyone considered doing a LQ4 or LQ9 swap as a poor man LS1 upgrade. My family is trying to talk me into saving money and time hunting by going with a LQ4 out of a Chevy Suburban 2500 thats been wrecked. I'm barley on the LS1 information level, now I need to research LQ4. Seen that its based on the LS1

OK I just did the the 5.7 aluminum ls1 swap and am planning on either a 370 or 408 Iron block lq4 build which is basically the same architecture as the 5.7 only differences between are besides the iron being stronger are,
1. iron vs aluminum which is 80 or so pounds weight difference....
2. 364 ci lq4 or lq9 vs 346 ls1& ls6
3. lq4 0r 9 are cheaper then a ls1& ls6..... lq9 are bit more seeing as they are the HP version of the lq4
4. lq4 has dished pistons vs lq9 flat top pistons
5. both Lq series use the same heads casting number 317 which is basically a 243 head with larger cc chambers which from which I gather are good heads for forced induction ie: turbo! early model lq series you want to avoid due to iron heads and a different crank snout.. I believe 99-01 6.0 I believe..
6. from I gather 243 heads or there twin heads 799 work great on a flat piston lq series engine once milled and matched to the pistons, cam, etc etc...
7. f body accessory drive will mount to a lq4 or 9 with the drilling of the block to accept the alt bracket
http://ls1tech.com/forums/conversions-h ... r-diy.html
or you can mod the truck accessories to the ls6 intake
http://www.performancetrucks.net/forums ... ap-359987/
basically what my plan is to disguise my lq4 to be a HP lq9 and look like a ls1...... this is all I have for now some info could be bad let me know I don't want to spread bad info! If I could I would to a 408 lq with a LS3 top end and but I don't know bout dbw... :!:

NOW there different variants of the 6.0+ 6.2 ls2, ls3 L76, LY6, L92 etc etc.... LS1tech is a very good tech site! research and do more research and you will find what you seek..

 

[Westbank of NOLA]

Thanks for the info. These are the 2 sites I have read over the last few days.

http://www.enginelabs.com/engine-tech/j ... to-riches/

http://oppositelock.jalopnik.com/speed- ... 1125469009

With this outline, a LS newb like myself has a roadmap on what to search for. I don't think I will be going in the boost direction, so I will probably hunt down the LS6 heads and dream of finding the L92 on my budget price.
The new argument is over the intake and transmission setup. They want the carburetor and 700r4, I say stick with the EFI and computer controlled transmission (depending on transmission clearance issues).

 

[skylarkul]

As 85GPLef41 recommended, the LS1 Tech forum is the best source for information on installing every version of "LSX" engine in every type of vehicle you could imagine. I also found the "Chevy LS Engine Conversion Handbook" by Shawn Henderson to be a very good information source for LS engine swaps.

 

[jacobdavis1979]

I also have the LS swap handbook. Great reading material.

As for the lq4 vs ls1 thing theres alot of ignorant people out there. I had a guy jump my *ss for wanting to put a 5.3 in my car he said why waste your time with those crappy Vortec motors when you could drop in an LS. Ignorant people seem to think Vortec and LS are 2 completely different engine families when in reality comparing a 5.3 to an LS1 isnt really any different than comparing 327 to a 350 there not as different as people think. 5.3, ls1, 6.0 its all gen 3 small block and in my honest opinion i would prefer a 6.0 or 5.3 than an ls1. Easier to find and i like the cast iron block

 

[War Machine]

as i know th400 is same size as 4L80e and u need a shorter driveshaft about both of them ... driveshaft yoke for th400 and 4L80e is different to yoke for thm350/200r4/700r4

maybe u better to think about having a overdrive transmission instead of thinking about fitment issues ...both th400&4L80e are strong/long life transmissions but got light first and second gear ratio , also it depends on your engine setup if u going with carb so 700r4/200r4 is easier to install/maintain and if u are doing it FI i suggest 4l60e

I'm pretty sure the 4L80e is bigger than the th400, but I'll look into that. I have them both in my shop so I'll just measure them both. I'm going FI. 4L60e, if built, usually only hold around 600hp. I'm looking to go far beyond that so I need a trans that's going to hold the abuse I'm going to throw at it. I plan to be mid 600s on spray for now and closer to 800 on boost.

 

[skylarkul]

There is a lot of information on GM transmission dimensions and gear ratios here: http://www.crankshaftcoalition.com/wiki ... nsmissions

For me, going from a 700-R4 to a 4L60E will move the engine (bell housing mounting surface) forward 15/16". Since both transmissions are the same length, it will also move the tail shaft (driveshaft mounting) forward 15/16". I'm not sure if I can get away with using the same driveshaft or, will have to get a longer one. I'll have to look to see if there is enough surface on the transmission cross member mounting to re-drill and move it back enough to compensate.

 

[War Machine]

There is a lot of information on GM transmission dimensions and gear ratios here: http://www.crankshaftcoalition.com/wiki ... nsmissions

For me, going from a 700-R4 to a 4L60E will move the engine (bell housing mounting surface) forward 15/16". Since both transmissions are the same length, it will also move the tail shaft (driveshaft mounting) forward 15/16". I'm not sure if I can get away with using the same driveshaft or, will have to get a longer one. I'll have to look to see if there is enough surface on the transmission cross member mounting to re-drill and move it back enough to compensate.

Cool, thanks for posting the link. Hopefully either way, I can get it all to fit nicely.

 

[onesickGSX]

Okay, I'm jumping right into the fire. Has anyone considered doing a LQ4 or LQ9 swap as a poor man LS1 upgrade. My family is trying to talk me into saving money and time hunting by going with a LQ4 out of a Chevy Suburban 2500 thats been wrecked. I'm barley on the LS1 information level, now I need to research LQ4. Seen that its based on the LS1

OK I just did the the 5.7 aluminum ls1 swap and am planning on either a 370 or 408 Iron block lq4 build which is basically the same architecture as the 5.7 only differences between are besides the iron being stronger are,
1. iron vs aluminum which is 80 or so pounds weight difference....
2. 364 ci lq4 or lq9 vs 346 ls1& ls6
3. lq4 0r 9 are cheaper then a ls1& ls6..... lq9 are bit more seeing as they are the HP version of the lq4
4. lq4 has dished pistons vs lq9 flat top pistons
5. both Lq series use the same heads casting number 317 which is basically a 243 head with larger cc chambers which from which I gather are good heads for forced induction ie: turbo! early model lq series you want to avoid due to iron heads and a different crank snout.. I believe 99-01 6.0 I believe..
6. from I gather 243 heads or there twin heads 799 work great on a flat piston lq series engine once milled and matched to the pistons, cam, etc etc...
7. f body accessory drive will mount to a lq4 or 9 with the drilling of the block to accept the alt bracket
http://ls1tech.com/forums/conversions-h ... r-diy.html
or you can mod the truck accessories to the ls6 intake
http://www.performancetrucks.net/forums ... ap-359987/
basically what my plan is to disguise my lq4 to be a HP lq9 and look like a ls1...... this is all I have for now some info could be bad let me know I don't want to spread bad info! If I could I would to a 408 lq with a LS3 top end and but I don't know bout dbw... :!:

NOW there different variants of the 6.0+ 6.2 ls2, ls3 L76, LY6, L92 etc etc.... LS1tech is a very good tech site! research and do more research and you will find what you seek..

Another advantage of the LQ series is that they the cheapest block you can buy with a 4'' bore. the advantage there is that you need a 4'' or larger bore for L92/LS3 or LSA/LS9 heads all 4 of which flow in excess of 300 cfm as cast.

Oh buy the way you can by L92 heads for around 800 bucks for an assembled pair. which is cheap as hell for the flow volumes. 8)

 

[85GPLef41]

Oh yeah onesickGSX...... I agree with the overbore on the lq4 or lq9 budget I have been wrestling with myself to do the l92 head and intake and reinspect my LS1 swapped GP to a LS3 swapped GP...OR building a 408 ls6.... from what I get from my tuner I should be able to get 450-480 HP doing the lq4 to ls9 with 799 heads and a mild tune..... 8) doing the l92 build 408 should make more HP at the cost of redoing everything ls3 wise... :shock: I also would love to do a turbo...... :lol:

 

[xodruxo]

Hi buddy just chiming in cause I haven't been on here for so long... lol, let's get this motor built soon...