Engine swap question

[Guest corey wasut]

Hello all,I have a 1988 Reatta with a bad engine i rescued from the crusher,car is black with a factory sunroof and has been a western car since new,so it was worth saving for sure!My question is this,the engine i want to install is from my 1991 pontiac Bonneville SSE,we only have about 40k on the engine that i purchaced from the gm dealer in 02,the car was rear ended a few years back so perfect for parts now.

Are there any major snags i might hit swaping the engine from the Pontiac to the buick?Physicaly they look the same,but someone said there are some major manifold/vacuum diferences.Any insight from you knoledgeable folks would be very much appreciated.

[Barney Eaton]

I believe you will find the Pontiac engine is a "L" series engine which started in 1991.

Your car has a "C" series engine. The Pontiac engine should drop right in place..........However, you must use the ECM (engine control module) for the Pontiac engine.

I am unsure about the transmission.... In 1991 the Reatta went to the new "electronic" transmission. I am not sure if all GM products switched.... a quick check of the 1991 Buick Product manual indicated that only the the Park Avenue, Riviera, and Reatta came standard with the "L" engine, the LeSabre continued to use the "C" engine.

You will need to do some additional research on the Pontiac engine to see if it is a "C" or "L" engine. If the intake looks like your 1988 it is probably a "C" engine.

[padgett]

Be best to swap both the engine and tranny from the Bonne. Does the tranny pan have a big "E" on the bottom ? I do not recall if the SSE (actually all Bonnies that year had the same engine/trans. The 1990 Bonne was the best four door sedan I have ever had.) got the "E" trans in '91, may have still used the 4T60 but with all of the upgrades.

Edited March 7, 2010 by padgett (see edit history)

[padgett]

Need to know which trans, we can go from there about the ECM.

[Guest Greg Ross]

Cory,

The '91 "L" 3800 drops right in, and the new style exhaust manifold collector on the '91 engine bolts right up.

If you stay with the stock tranny you do not need the Pontiac ECM (trying to use the Pontiac ECM I believe would create all manner of nightmares with the BCM Data Link communication)

Very minor wiring harness modifications are required, as I recall you have to reroute the Fuel Injector harness to get it to reach, probably the oil pan level sensor, that's about it for wiring.

Plumbing-Fuel Lines, the connections at the regulator are different so you'd have to use high pressure fuel hose to make up those connections.

Transfer the cruise control module over to the '91 "L" and you'll have all the stock features.

Difference on the type of EGR valve needs to be dealt with, with no "Smog Testing" here in Canada I have a solution for that. I'm in Calgary by the way with my S/C '88 5-Spd.

Send me a Private Message.

Regards,

Greg

[Guest corey wasut]

Thankyou everyone, a bit of online research tells me that my Bonneville (still the old style model) is a "c" series engine,the same 165 hp model as in the Reatta,so there should be no problem at all.I will be so happy just to see the Reatta running.

[padgett]

1991 SSE ? Sure you have the "log" intake manifold and not the "snakes". (Coulda swored)

[Guest corey wasut]

91 sse looks the same as when they came out in 88,before they went to the cat-eye look in 92,which i assume is the one lith the "l" series engine.The engine looks identical to the reatta.(no snakes)

[padgett]

No, like the Reatta, the 88-90 Bonne had the "C" engine but the 91 (still square body) got the "L". Slant eye cane out in '92 (Won't talk about the 87).

Can verify on the Bonneville Forum .

The difference is easy to spot, just look at the top of the engine. If you see six tubes in the middle it is an "L". One log and it is a "C".

[DAVES89]

Or look at the "vin". If it has a "C" in it, it's a "C" motor "L" it's a "L" motor

[Don B.]

You may need to change the oil pan sensor.

The Reatta has a float to let you know oil is low.

The pontiac may have a oil usage sensor, let you know how dirty the oil is.

[Guest corey wasut]

Well it's finally done! Engine swap went great and the old Reatta is running very well again, now the CRT screen is doing this strange " fuzzy " where it gets all distorted and then goes clear again (like a T.V that has an unclear station) this was a wee bit annoying trying to make sure the engine had good oil pressure and was keeping cool with no screen. Now its time to track down all the little interior odds and ends i need. Still fall in love all over whenever i look at the car!

[NCReatta]

Could be your CRTC starting to go out.