Iron Duke vs. Quad 4 ?

[GrandAmJan]

What's your opinion....

1: If you had to choose between a 1991 GA with the Iron Duke or a Quad 4, which would you prefer? and why?

2: Which do you think has more problems: Iron Dukes or Quads?
(I've heard to run far far away from a SOHC Quad 4... but that DOHC is better:???: .)


I'll be looking at a "granny-driven" 1991 GA with 53,000 miles next week and she doesn't know which engine it has... but since it is automatic I'm assuming it's not a HO Quad. I've got a 1989 with the Iron Duke which just won't die :guns: .. and I'm not complaining.. I'm hoping for a Duke in this other one but wonder what opinions are about a Quad 4.

Thanks for any input. I'll let you know what the car is like. If I don't want it maybe someone in here would. ;)

[urweak]

well the quad 4 is going to be faster for one.

From a performance stand point. The Quad 4 is more reliable when you start adding power to it. The duke will just blow up. But stock, they are probably about the same. But if i had to pick, it would be a quad for that extra oomph.

[nineteen88ga]

Originally posted by urweak
well the quad 4 is going to be faster for one.....

The duke will just blow up.

A moddedor probably even stock for stock.... Quad 4 being faster...hell yes.


I wouldn't say the duke will just blow up. They're one of GMs strongest motors as far as reliability and econemy, so I wouldn't expect them to be power houses either. I've been spraying a 35 shot on my 2.5 for the past 2-3 years with 108,000 miles on it and have yet to experience any major problems.

If you don't want to have to do the head or if you want virtually a bullet proof motor, look into a nice low mileage (if you can find one) 2.5. Just don't expect a race car out of it.

hmm if its in nice shape and a coupe I may possibly be interested..if the price is right of course. It wouldn't matter to me on the motor at all either. I just personally Love the 85-91 body style.

[Matt95GT]

Being that both are automatics, you're prolly not going to make a race car out of either. If that's the case, and you're just looking for a daily driver... I would choose the Iron Duke for it's long-term reliability, easier to work on, and tons of replacement parts available in the junkyards.

[ramairgt2]

definitly go with the duke. I've gone through to many quads already.

[ViperDVMan]

It depends on what you're gonna do with the car. My "Duke" has been a pretty solid motor, save for a little problem arising now and then, only because the original owner neglected it. The "Duke" is a bulletproof engine, and replacement parts can be found pretty easily. Any pre-92 N-body (Calais, Skylark, Grand Am) and any A-body will have that motor in it. Even the Pontiac Fiero used the "Duke".

But do be careful, 'cause the "Duke" was updated in '88 with a force-balancer type oil-pump which moved the oil filter from the block to the oil pan. So if you want to look for parts at a junk yard, make sure they're from an '88 and newer motor.


Back to your original question....I'd prefer the Quad4 for its power and performance part availability (the "Duke" has almost zero aftermarket support). I eventually want to swap my "Duke" out for a custom Quad 4, but for now, I'll keep my Duke.

[GrandAmJan]

Thanks for all the great input, guys.

The lady went on vacation so I'm still waiting to take a look at the car. :sleep:

Steve :fyi:: It's a 4-door. :tears2:

[ramairgt2]

hey nothing wrong with a four door. I have one ;)

[GrandAmJan]

I agree, ramairgt2. ;)
I've had a 4 door 1989 for almost 18 years and love it... :D
I thought I'd let Steve know this 1991 I'll be looking at is a coupe since he said he might be interested in it if it's a coupe.

[91Grandayyyum]

i own a dark blue 1991 4door Iron Duke with 63,000 original miles and the car has been nothing but good to me. never any major malfunctions that required serious work to fix. if you are looking for something to be used as a daily driver my vote is Iron Duke all the way. now ill admit this motor is very weak but if i wanted to go fast, id buy a trans am. sure the quad 4 might be more fun to drive but its no race car by any means. as far as mods go, there are none for Dukes but i guess quad 4s have some options.

if i were to do it all over again, id still take my Duke.

[nineteen88ga]

Originally posted by 91Grandayyyum
as far as mods go, there are none for Dukes but i guess quad 4s have some options.

if i were to do it all over again, id still take my Duke.

Wrong. their is actually quite a bit available for the 2.5. Not very many bolt ons such as CAI's etc. Look at some fiero sites if your interested in mods for a Duke. Most are internal from cams, and valve train, to using a mercruiser crank to bump it up to a 3 liter.

http://www.k12.nf.ca/gc/Staff/Teachers/Crummey/fiero/

I tried the link a few days ago and it didn't work, but it gave a fairly indepth detail on a moddest build up.

Also TBIchips.com burns custom prom chips for the ECU.

[grandamle91]

My Duke Is Sitting At 289k and stills drives and runs great, and i rod the $*#& out of it.