i was wondering will 3.4 (push rod) heads fit onto a 3.1 out of an apv van?

if the 3.4 has iron heads and the apv has aluminum heads than no they wont work, if the 3.1 has iron heads then youre good to go. i havent worked on many apv's but i think it has aluminum heads making it a 3100 engine not a 3.1(iron headed)

What year is the 3.1? If it is a newer engine with aluminum heads, the old 3.4L iron heads change the compression to some really low number like 7:1. The aluminum heads on the 3.4L block change it to 13:1 or something like that.

What have you in mind with the question?

i don't know what year the 3.1 is but the heads will be reman through the parts store i work at. what i want is the bigger valves and stiffer springs of the 3.4. at least that's what i have read on the 3.4, is that correct? if so it is way cheaper than having bigger valves cut into the 3.1 heads. any who that is my question.

Yeah, if it's an older APV (early 90's), it has cast iron heads just like the Fiero, only smaller valves (1.6"/1.3" vs. 1.72"/1.42"). Supposedly, it's just a matter of switching valves.

from 1990-1996 the APV had a iron head 3.1L as an option, it was rated around 120HP 160ft/lbs and yes with a simple head change it becomes a high output motor, (dont know why it didnt have the high output heads to start with)

ive swapped one into a fiero before, and all you really need to do is change the timing cover oil pan and intake assembly's, it also takes a fitting to make the oil pressure switch work properly.

matthew

yes - all iron heads are interchangeable.
but, there are early "small valve" versions - mostly from old carb'ed chevy S-10's

so i am safe to put the heads, but will i see a gain with the 3.4 heads?