General spec info

[yaahoos]

I am new to GM stuff really, but was wondering with my new 85 GP purchase , ( and not being a mechanic) I am trying to find out how “stock” my car is? It’s a 305 V8 , but carb looks like a quadrajet ( a little big for a 305 ?) It also has dual exhaust but drivers side goes under the oil pan and goes along side and parallel to the right side. Craziest thing I have ever seen. And that transmission mount is like a giant “s” shape with a couple of small rust thru parts?

This is one odd car ??

 

[500/600]

Perfectly common. Crossmember needs replaced. Exhaust is not stock.

 

[DRIVEN]

^^^This^^^

 

[yaahoos]

Perfectly common. Crossmember needs replaced. Exhaust is not stock.

Thx. Does the stock dual exhaust go side by side under the “flattened “ part of the transmission mount similar to this? I’m wondering about “where would I place header pipes”.

 

[ck80]

As stated above, all that looks stock except a strange aftermarket/custom exhaust routing.

What's not commonly known about the quadrjet is that, if you keep your foot out of it, you typically see BETTER potential fuel mileage than a dualjet. The primaries on a qjet are smaller in size than the dualjet, and if driven gently see better mileage.

That said, standard equipment on the ole lg4.

 

[ck80]

Thx. Does the stock dual exhaust go side by side under the “flattened “ part of the transmission mount similar to this? I’m wondering about “where would I place header pipes”.

There wasn't stock "true" dual exhaust on gbodies. It was a single intermediate pipe that ran down, then at the muffler it got twin tailpipes on the models that had it. Most just had single tailpipe as well.

 

[TURNA]

The person that did the exhaust just ran the drivers side pipe to match the original factory Y-Pipe location so that it would clear the Xmember

Looks like they did a nice job at it too

 

[olds307 and 403]

It would have been a factory Qjet, it will work fine. The air doors if adjusted right only allow the amount of air needed. It should also have a vacuum advance HEI distributor. It should be non computer controlled on a Canadian 85 car. I got this custom exhaust on my 88, same idea in 2.5" pipes.

 

[MrSony]

Replace that cross member. If your car has 3 gears, you need a crossmember from a car with 3 gears. ANY 1978 to 1988 A/G Body with a 3 speed automatic will have what you need. Buick, olds, Pontiac, Chevy, don't matter. Just has to be a g body. The 4 speed uses a different crossmember.


As said exhaust is not stock. I think walker exhaust might still make replacement parts if you ever want to go stock stock.
Or if you get a beefy G Force dual hump crossmember you can run normal true dual exhaust.
Its the orange thing. They don't come orange. Ig this guy painted his.

 

[MrSony]

Oh, and quadrajets are the factory carb. 750 MAX cfm, though it probably only uses maybe 500. Can't overcarb with a qjet. GM used them on everything from turbo 3.8 buicks (before 1984) to the 307 olds in 1988 cutlass'. It was phased out in 1991. If it runs bad, take the time to learn to rebuild it. Its not hard. Takes about $150 to rebuild it the right way, but its less than half the price of a new carb. Most however can get buy with just a gasket kit, new float, and accel pump. Thats about $50.
Quadrajetparts.com

Type in your carb number (1708xxxx) on the drivers side by the linkage, and grab what they say fits your carb.