3800 swap

howdy. My friend has a 95 grand am with a 3100. we were goin to put a 3400 in it but know he wants to put a 3800 gtp motor in the grand am. The problem is we can't find any kits for the swap. Does anyone know of a site or person that has swap out a 3100 for a 3800 in a grand am??? or a better site to ask question on??? thanks


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i know of one person that did this,but he had a 4 banger in his,i believe that hotrod magazeen featured and article on this same question.you might go to hotrods web sight and ask the same question,they are probably more likely to be able to give you some info on the swap.

In 1990 and '91 Grand Ams and Olds Calais' came with 3300's which are the same basic engine as the 3800. I think even some '92s. They were common, rusted badly and can be purchased in running condition CHEAP. There's your kit as far as mounts, brackets, etc. the 3800 will bolt up to the current transmission but it might not survive behind a 3800, that probably has the 4T40E which is the same trans the 4 cylinder cars used , the 3300 cars didn't have OD but they used a much stronger transmision, I'd swap in the 3300's trans too. Get the ECM and harness from the car the engine came out of or you ight be able to use the 3300 harness depending on which way you go on the transaxle. You'll probably need to do some wiring mods and have a custom chip burned but it's worth it. A Grand Am with a 3800 would be a lot of fun.

thanks alot for all the info.

If your going to all the trouble for more power why not put a caddy north star in it! Ive seen that done before in a magazine, looked fairly easy. Would be a tight fit an a grand am, but so would a 3.8.

yeah my brother law said he might do that instead, but i think 3800 might be cheaper maybe out of gtp or ssi.

a 3.8L ina grandam fits like it belongs there- because it is basically the same dimensions as the V6 it runs externally. I would def. get the supercharged one though.

Yep the 3800 would be cheaper and easy. But a northstar would be Cool and worth the extra effort IMO.

The 3300 the factory installed was tight but it has the same external dimensions as the 3800 and it fit, the Northstar is HUGE compared to a 3800. I've seen pictures of them swapped into a W-body (Grand Prix, Cutlass, Lumina and Regal) and there was some cutting involved and it was REAL tight, putting one in an N-body (Grand Am, Calais, Acheiva and Beretta) would require major surgery. I seriously looked into swapping a Cadillac 4.9 into a Grand Am and I used a friends 3300 powered Grand Am to take measurements from, it lacked about an inch on the passenger side of fitting without cutting out half the inner sheetmetal and it was real close front to rear. While scoping out 4.9's in the local yard I did a lot of comparison to the Northstar and it is noticably larger externally than the 4.9, requires a lot more room front to rear and would also require major modifications to the cradle. Then you would need to swap in the 4T85E transaxle to go with it if you had any hope of keeping a tranny behind it and your into more floorpan mods, custom axles, suspension mods and on and on............ The 3800 can be put in with mostly factory parts and no cutting required. Keep in mind though the 3300 is a Series I, in '95 some 3800's were Series I and some were Series II, the Series II might have some differences that would preclude using mounts and brackets from a 3300, something to look into before choosing your engine.

Wow put me in my place! Im kidding. the way I look at it if its worth doing its worth doing right. But you are correct I did'nt see the Grand am part,thought it was a Grand Prix. Yes a G A would be a major undertaking to Install a Northstar. But I have seen the Install in a W body and it look fairly uncomplicated.

Wasn't trying to do that but I strayed to the "Dark (FWD) Side" for a while and had considered some of these very same swaps. I eventually regained my senses and returned to my RWD roots.





It has been done but it's not a "bolt in" by any means.

I myself am a fan of the Grand Prix, not much the Grand Am. I'd like the '95 Grand Prix to have a 3.8 II but I would also like RWD. Is there a RWD tranny that would bolt to the 3.8 II and take the beating? Maybe a 700-R4? Doubtful but its just a thought.

well a rwd 3800.....some 96 firebirds had those and the trannys in them were stout!!

Actually, it does. The FWD 3800 Series II motors use the same bellhousing bolt pattern as the 60 degree V6 motors (2.8, 3.1, and 3.4). The 700-R4 from the 2.8 S-10s will bolt directly to the 3800 Series II block. Also, the fourth gen F-body cars used the FWD 3800 block in a RWD application, so the transmissions from those cars (AT and MT) also bolt up to all FWD 3800s including the SC motor.