3800 engine swap question

I have a question regarding a engine replacement in my van.

The van is a 1995 Pontiac Transport with the 3800, the block is cracked and I have access to a 1990 3800 (both are series 1) with low to what I'm told -no- miles on it. It is from a LeSabre

Whaat kind of issues/problems could I run into with this swap?

Any help would be appreciated...thanks

Just a first impression, no experience with that swap but I think the main concern is '90 is OBD1 and '95 is OBD2+airbags..... I do not have the complete picture but a serious consideration about computer and hardware/wiring is part of the game.....might be a problem with regulatory inspections if applicable where yoiu live....; like EGR contgrol is not the same: linear in '95 and 3-ports probably in '90.

Expect expert advice from other forum members....

Tricky ground there....

I will assume this is a Vin C 3800 that you are going to use.....

First the 1995 van used 9.0 : 1 compression as opposed to the 1990 3800 at 8.5 : 1 compression... The 95 3800 also used a roller pivot as opposed to the 90's pivot for the rocker arm...

The 95 used an internal PCV system where the 90 did not...

For all intent purposes, you could install the 95 heads on the 90 block and install all the 95 parts including the exhaust manifolds and the like.... I am quite sure that all of the bolt bosses are the same, but you would have to make sure of that...

Not so sure I would bother to go this route... Then you'd need to use the 90 balancer and flywheel.... The crank sensors are different... 93+ is non adjustable, 92 and under are adjustable...


In all honesty its way easier to find a 93-95 Vin L 3800 and drop it in... 95 was a very funky year as well for the engine and PCM....

I am sure it can be made to work, but even me being me this is one I would shy away from due to the level of work involved... I think it was easier for me to drop in my series III then to do the swap your thinking of..

Tricky ground there....

I will assume this is a Vin C 3800 that you are going to use.....

First the 1995 van used 9.0 : 1 compression as opposed to the 1990 3800 at 8.5 : 1 compression... The 95 3800 also used a roller pivot as opposed to the 90's pivot for the rocker arm...

The 95 used an internal PCV system where the 90 did not...

For all intent purposes, you could install the 95 heads on the 90 block and install all the 95 parts including the exhaust manifolds and the like.... I am quite sure that all of the bolt bosses are the same, but you would have to make sure of that...

Not so sure I would bother to go this route... Then you'd need to use the 90 balancer and flywheel.... The crank sensors are different... 93+ is non adjustable, 92 and under are adjustable...


In all honesty its way easier to find a 93-95 Vin L 3800 and drop it in... 95 was a very funky year as well for the engine and PCM....

I am sure it can be made to work, but even me being me this is one I would shy away from due to the level of work involved... I think it was easier for me to drop in my series III then to do the swap your thinking of..


Thanks so much for your input on this, this is exactly what I needed to know

Just keep this in mind.... the 95 Vin L is unlike any other... If you get a 95 Vin L you have to use the 95 Flywheel and balancer it has on it... Do not use a 93-94 Balancer or flywheel on a 95 motor...

the 95 Vin L actually uses a series II crank, oil pan and I think the same flywheel... Balancer is 1995 Vin L only... so these parts can't interchange..

This thread added to my collection