N body 2.4l to 3.1l swap, how difficult?

[jaons_Wlp]

Hello, im new to this forum and need some assistance. I have a 96 grand am with the twin cam engine and i would like to swap the 3100 into it as that was an option from the factory for the car. There is no other grand am in as good of shape as mine in my area so im not looking to buy a 3.1 grand am. Just want to do the swap. So with me being able to find a sub frame and mounts that are made for the engine to go in the car, how difficult would it be? like can the accessories interchange, use same radiator, can the front suspension handle the weight, ect... It has the isuzu 5 speed in it now and ive read the quad 4 has a unique bell housing to its self. cant i just swap the bell housing from the cavalier/sunfire 2.2 ohc trans? Thanks for any info

[Guest]

The biggest issue will be the electrical. In stock form the PCM needs to talk to the BCM and a few other modules in order for everything to work. Since there was not a manual V6 N-body of that generation this will be more difficult, though I have read about people re-programming their PCMs for a trans swap, in an originally V6 car.

Mechanically you would just use the V6 parts to get the engine installed.

I don't know if the belhousing can be swapped between the transmissions that you are suggesting, IIRC they are actually different transmissions.

[caffeine]

You might be able to find an appropriate Isuzu bellhousing from a 96-99 2.2 J-body

[1988GTU]

The front end might sag a little more with the suspension difference, but you might be unaware of it if the struts are in good shape and the springs are in good condition.

It would be best to find a V6 trans rather than try swapping the bell since the bell is actually mostly the trans case.

Radiator is different, and I think the alt, PS, and fuel soft lines are different too. With most of those being capable of swapping the case or reroute of the hoses, it can probably be used... but unless you already have the correct items to swap it over to, it would be best to just obtain the right parts.

Lastly, since you are going thru the trouble in converting over to a V6, you might consider a 3400 or a large port 3100.

[jaons_Wlp]

thank you all for your advice. The electronics issue ill worry about last cause im handy with wires and charts, and ill have the pcm tuned/programmed(what websites can i visit to check prices?). Now as far as transmissions go, these 4 cylinder trans use the case as the bell housing too or does the bell housing separate? My trans works just fine and id love to leave it in but ill throw in the trans from the 2.2 ohv j-bodies if it can take the extra torque. The front end has much stiffer coil springs cause the car is lowered 1.8 inches so that should be okay then. Sure i would much rather swap in a 3400 3.4l but how much more involved is that? will the 3.1 mounts still work? if not ill use the 3.1 and keep the hassle to a minimum. is the large port 3.1l you're referring to the newer LG8 3.1? thanks

[caffeine]

The bellhousing seperates but also houses the diff and is part of the case. The Isuzu trans in the 2.2 J-bodies should be the same as yours except for the bellhousing. If you're looking for something stronger, the Getrag F23 from the 00-02 2.2 J-bodies will also bolt up to the engine but I have no idea if the mounts are the same.

[jaons_Wlp]

hmmm, ill look into the f23. I "hope" the mounts are the same since the cavalier didnt get completely remodeled past 1999 like the grand am did, and carried over the same engine. thanks

Are the final drive ratios the same between the two trans? If so or its shorter ill just swap the housings and find a lsd locker if they still make them for that trans.

[Guest]

Just to clarify, when you say "3.1" are you refereing to this engine:

(gen2 3.1)


or this:

(gen3 3100)


the later (gen 3 3100) is what would have come in your car if it were born with a V6. To make it easy to know which generation people are discussing we call these "3100", to differentiate them from the gen 2 "3.1" (there's also a gen 1 3.1, but we won't go there). The large port 3100 (6 upper intake bolts) and 3400 can be swapped easily in place of the small port 3100 (12 upper intake bolts), using teh same mounts and electronics.

[jaons_Wlp]

oh im sorry. thank you for making that clear. I have been talking about the 96-98 3100 all along. The 3400 can use the same harness as the 3100? and zero alterations to the mounts?

[1988GTU]

oh im sorry. thank you for making that clear. I have been talking about the 96-98 3100 all along. The 3400 can use the same harness as the 3100? and zero alterations to the mounts?

The difference in the 3100 to 3400 is the stroke and bore. By natural technological advancements, the 3400 might contain added provisions while keeping prudent 3100 necessitative compatible capabilities.

You can install the 3400 just as if it were a 3100 physically.

[Superdave]

The difference in the 3100 to 3400 is the stroke and bore. By natural technological advancements, the 3400 might contain added provisions while keeping prudent 3100 necessitative compatible capabilities.

You can install the 3400 just as if it were a 3100 physically.

Just bore increase, same stroke.

3100 and 3400 have the same mounting bosses so mounts are interchangeable. Might be slight changes in the wiring depending on what injectors you use, possible EGR and some other random stuff. Nothing too difficult.

[jaons_Wlp]

Okay great, thanks. Ill grab a 3400 from a pontiac aztek then, and the 3100 mounts. will i have a problem passing emissions with the swap? The vin will say the car is supposed to have a 4 cylinder. and can i combine the 2.4l dash harness with the 3400 engine harness?

[1988GTU]

Carefull of where you obtain the 3400 from. Some may have cracked heads. I'd stick to sedans for ease of checking out prior to purchase.

[pocket-rocket]

Carefull of where you obtain the 3400 from. Some may have cracked heads. I'd stick to sedans for ease of checking out prior to purchase.

I've been told the rear heads on vans also are more prone to cracking because of the lack of circulation.

Don't the van uppers also flow the worst of the 3400 manis? I believe there is an article on this site that shows the best flowing uppers and such, compliments of WOT-TECH.

[jaons_Wlp]

Thanks guys. I know where plenty of impalas are at so would that be my best bet? and info on combining the 2.4l dash harness?