jeffcanada Posted December 23, 2003 Report Share Posted December 23, 2003 I am finally taking serious steps towards swapping out my 3.4L DOHC for an excellent, low mileage 3.1L. The yard that I am dealing with suggested that I check about transmission compatibility. Will the 3.1L bolt directly to the 4T60E that is in my car? He suggested that the blocks may be different (despite both being 60 Degree GM V6's), and since the 4T60E was not available for the 3.1L that it might not bolt right up. Is this the case, if I go with a 3.1L, will I also have to get a tranny that was originally available for that engine? I mean straight bolt up; no custom machine shop plates to adapt to 4T60E or anything of the sort. If I would have to get a tranny along with the 3.1L, I may just go with a 122,000 km (75k less than what I have now) 3.4L DOHC he has for $1250 CA fully warrantied. Thanx, Jeff Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted December 23, 2003 Report Share Posted December 23, 2003 Yes, the tranny will bolt up, but the subframe of the DOHC is a little different, the location of a motor mount is different from the 3.1L subframe. Look into getting the subframe too. The 3.1L was offered with a 4T60E in 93 and 94 in Luminas, so you're safe. Just get the computer from a 3.1L that had the 4T60E Quote Link to comment Share on other sites More sharing options...
patgizz Posted December 23, 2003 Report Share Posted December 23, 2003 no need to get the subframe too. they are exactly the same from 91-94 and have both mounts for the 3.1 and 3.4 - it is in 88-90 that you would need to change to the newer one or modify the original. Quote Link to comment Share on other sites More sharing options...
jeffcanada Posted December 23, 2003 Author Report Share Posted December 23, 2003 Thanx for the info (my car is a '92, so no need for new subframe) So what additional parts would I need?: 1. Wiring harness for 3.1L. 2. Computer from a 3.1L that had a 4T60E. 3. New mounting plates for torque struts, and new dogbones. What else? Quote Link to comment Share on other sites More sharing options...
Justin Posted December 24, 2003 Report Share Posted December 24, 2003 it is in 88-90 that you would need to change to the newer one or modify the original. I assume you mean if you're going to swap a 3.4 into a W, right? Since the 3.4 came out in 91? Quote Link to comment Share on other sites More sharing options...
will Posted December 24, 2003 Report Share Posted December 24, 2003 i just went the other way 3.1 to 3.4 in a 96 trany bolts up the only mount the is the same is the one on the trany driver side the 3.1 has two upper dog bones and mounts only one mount on the pass side in the middle the trans filler tube is dif. angle may work 3.4 to 3.1 it didnt work my way i had to replace mine Quote Link to comment Share on other sites More sharing options...
93GTP Posted December 24, 2003 Report Share Posted December 24, 2003 I'd never be able to downgrade like that. I think you should go for the low km 3.4 Quote Link to comment Share on other sites More sharing options...
Brian P Posted December 24, 2003 Report Share Posted December 24, 2003 Leave the guy alone, he didn't ask for anyone's opinion on his engine transfer. Quote Link to comment Share on other sites More sharing options...
93GTP Posted December 24, 2003 Report Share Posted December 24, 2003 Sure he did, he said he was considering another 3.4 with low km's... Quote Link to comment Share on other sites More sharing options...
Brian P Posted December 24, 2003 Report Share Posted December 24, 2003 If I would have to get a tranny along with the 3.1L, I may just go with a 122,000 km (75k less than what I have now) 3.4L DOHC he has for $1250 Quote Link to comment Share on other sites More sharing options...
PaPaPooh Posted December 24, 2003 Report Share Posted December 24, 2003 I may just go with a 122,000 km (75k less than what I have now) 3.4L DOHC he has for $1250 CA fully warrantied.Thanx, Jeff Quote Link to comment Share on other sites More sharing options...
patgizz Posted December 24, 2003 Report Share Posted December 24, 2003 you can re-route some wires and use your original 3.4 harness on the 3.1 as well and just get a chip from a 93 3.1/4t60-e W and you should be just fine. Quote Link to comment Share on other sites More sharing options...
Brian P Posted December 24, 2003 Report Share Posted December 24, 2003 Christ. What is your comprehension level? Read the fucking paragraph. Go ahead and bicker and I'll do otherwise Quote Link to comment Share on other sites More sharing options...
93GTP Posted December 24, 2003 Report Share Posted December 24, 2003 I don't know what your problem is, I was only posting my opinion on how I think he should consider getting that 3.4 instead of going with a 3.1. It's a crime against nature to put a 3.1 in a once 3.4 car. Damn man you need to calm down. Don't insult my comprehension level, if I were dumb I wouldn't have just passed term 4 Mechanical Engineering. I know exactly what he said, but I don't think my comment was at all offensive, and was only a simple opinion. I never stated he had to do anything. If people were afraid of other people's opinions, I don't think they would have joined an online forum. Quote Link to comment Share on other sites More sharing options...
Vegeta Posted December 24, 2003 Report Share Posted December 24, 2003 christ brian, someone drop a dohc block on your foot lately? Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted December 24, 2003 Report Share Posted December 24, 2003 Christ. What is your comprehension level? Read the fucking paragraph. Go ahead and bicker and I'll do otherwise Werd. He said IF he would have to change trannies from what he has now, he would think about a lower mileage TDC. Now, JeffCanada, have all your questions been answered? Quote Link to comment Share on other sites More sharing options...
jeffcanada Posted December 24, 2003 Author Report Share Posted December 24, 2003 Now, JeffCanada, have all your questions been answered? Well, let me see, I got lost in the bickering (which I didn't really understand either)... Ok, so if I go with the 3.1L: 1. I will not need a new subframe since my STE is a '92. 2. I can either modify the DOHC wiring harness or get one from/for a 3.1L. 3. I will need a chip or computer from a 3.1L that had a 4T60E in it. 4. I will need to install appropriate torque struts and their mounts. That's it? Personally, I don't see this as a terrible downgrade. Firstly, I'll get an engine far less prone to problems, and when they do come up they are twice as simple to fix and take half as long as the DOHC. Quite frankly, I'm really tired of hearing HP this, HP that. HP doesn't make a shit of a difference in my opinion. I'd much rather have a car with higher torque, and power available in the low end (where most of us spend 95% of our time driving). What the hell do I care what power is available at 5000 rpm? The car will never see that on the street; maybe on the strip. To each their own, and for me that's a more serviceable and maintainable car, with better low end performance. Quote Link to comment Share on other sites More sharing options...
Robby1870 Posted December 24, 2003 Report Share Posted December 24, 2003 Yeah, Jeff, I think thats about all you'll need. If it were me, I'll get a whole 3.1L harness rather than modify the DOHC harness, but thats me. Good luck, and if you need anything else, just let us know Quote Link to comment Share on other sites More sharing options...
patgizz Posted December 24, 2003 Report Share Posted December 24, 2003 i'd stick with the harness you have, it will ensure not needing to re-wire the transmission plug. basically you need to just route a few wires differently, not cut/splice or anything like that. just cause a few sensors and the alternator are in different places on the 3.1 and 3.4 i am using a 3.1 harness on my 3.4, just had to move a few things around and it was simple to do in probably 10 minutes Quote Link to comment Share on other sites More sharing options...
ThunderBat Posted January 1, 2004 Report Share Posted January 1, 2004 I realize I'm just thinking out loud here, but since I've been considering looking for a cutty ragtop and I've done some online shopping...I've run across a couple with an expired 3.4DOHC and I must admit to thinking about doing this very same swap for some of the very same reasons "jeffcanada" cited. After doing some reading over at 60degreev6.com, there seems to be a fair amount of performance upgrades for the 3.1...cams, genIII heads, intakes and bigger TB's, all seem to have the makings of a great street screamer. While the 3.4DOHC is a great performance engine, it seems like it requires a lot of attention. Of course I haven't owned one so I may be talking out the side of my head here. While we're on the subject here, is the 3400 a bolt in swap ? or is that major surgery like going to the L67? Quote Link to comment Share on other sites More sharing options...
4spdz34 Posted January 2, 2004 Report Share Posted January 2, 2004 to each his own. i like the dohc and alot of people like the 3.1 personally i wouldn't want a 3.1 unless it was turboed . and on the performance thing. ya theres stuff u can do to the pushrod but for the cost and down time u could just as easy put a dohc in. its all in preference. and there are things that u can do to a dohc, u just have to be creative. evryone says the dohc autos are slow and have no torque. u get the right setup and they are damn fast outta the hole. just my 2 cents Quote Link to comment Share on other sites More sharing options...
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