Ok now that i know its an lq1 3.4 the only thing you can use from the 3.1 is the starter. And its more than just an engine swap. You need to change: tranny, tranny lines, wire harness, pcm(you dont have to worry about the passkey on this model), cv axles.

 

I'm pretty confident woodr004 has a typo possibly in there.

When he said "I have a 1997 Monte Carlo 3400 with 65k miles on it", i think he meant 3100 not 3400.

But, hopefully he'll stop in and clarify what donor car the good engine came from.

 

Yeah clarification would b nice as the two 3.4s r two totally dif animals

 

Sorry Guys for the confusion. This is a 3.4 L DOHC V-6 out of a 1997 Monte Carlo. I was unaware that 3.4 and 3400 are not the same engine. So assuming (***/u/me) that it was the same I purchased this engine. Of course it only has the water pump on it so I need all the rest. Will this engine drop easily into the vehicle or am I going to have to do a lot of modifications?
Thanks for clearing this up for me!
Pat

 

It will bolt into the car you will need a 97 lq1 wire harness pcm and 4t65(along with 4t65 cooling lines and axles). If you dont have the donor car you may b better off selling the lq1 and going 3800. If you havethe donor i can get you the rest of the parts cheap And dont feel bad, im the king of (***)(u)(me)ing

 

Don't worry about it, everybody forgets or doesn't really know about the LQ1. I made that mistake as well when I bought my 94 Cutlass Supreme with the LQ1. I thought it was the last generation to the 3400, the same way the 3100 is related to the 3.1 MPFI known as the LH0.

The engine drops easily in the car... that's not a problem. It was available in the car. The problem is that NOTHING other than the starter swaps from a 3100 to a 3.4 DOHC. Not only that but the engine is pretty maintenance prone. You have to really keep up with it. Granted it's rewarding, but there's not much of a difference between the power of a LQ1 (3.4 DOHC) and a L36 (3800). The LQ1 is more of a Honda type engine. You can rev it to 7000 rpm and nothing happens to it because it was designed to be rev happy.

But assuming you want to keep the LQ1, you will need to reprogram the PCM on your 97 M/C or you will want to fetch the one from the donor car. You will also want the wiring to the LQ1, the transmission (the 3100 trans is weaker and has different gearing)(the LQ1 and 3800 use the 4T65E, but the 3100 uses the 4T60E), and any accessories. Basically, you'd be doing a subframe swap. It would be easier that way.

If you want a basic drop in that's not a 3100, THEN you can get a 3400 out of a minivan (Venture, Montana, Silhouette) or out of a Grand Am/Alero. They were also in the Malibu and FWD Impalas (and related Monte Carlo). The Monte Carlo that has the 3400 is the 2000 - 2005. If they were from the late 90's they don't have them!!!

 

Thank you all for helping me here. I learned something new! I think I am going to follow the advice and sell the LQ1 on Craigs List and get a 3400 to drop in. I really don't feel like find a wiring harness, axles, etc.. I just want my daily driver back.

Here are a couple of additional questions, my 3100 tranny is getting weak, I have access to the 4T65 that came with the LQ1. It only has 65K on it. If I got that would a 3400 bolt directly to it with no issues? My second question, if I can get a 2000-2005 3400 out of a Monte, should I take that over the other 3400's and will it bolt to the 4T65 with no issues?

Pat

 

It'll bolt up fine but the gear ratio is different, which would have to be changed in the PCM

 

Youll need a wire harness and pcm from a 2000-01 lumina to make a 4t65 work. Youll also need a 4t65 with 2.93 gears(lq1 has 3.42 iirc) recently did a 4t65 swap on my 3.4 la1 97 monte. And despite common thought an l36 torque converter will bolt to a 3x00 engine. Any more questions on 4t65 swapping your car feel free to ask me

 

Which btw im about to go the 3.8 route so if you have trouble finding a pcm and harness, im bout to have one id sell cheap already modified for plug and play