3x00 hybrid swap in a fiero

[mtownfiero]

I have a full 2nd gen 3.1l running in my fiero using the 7730 and a modified fiero harness to run the motor. However i feel like for all the work the swap was i didnt get much out of it being the only increase in power was 15ftlb of tq. SO.. i decided that i want to start accumulating parts for a 3x00 swap.

I read through the 3x00 site and got some good information but figured i should go over it on here becuase of how many have done it.

It seems like the 2000+ intakes and heads are the way to go for the biggest gain because of the D ports. My 3.1l already has the newer better 3x00 manifolds so i also wont have to modify my exhaust.

The shopping lisit seems to be

2000+ 31 or 3400 heads
2000+ uim and lim 's
fuel rail + injectors

my motor now uses an 87 style timing cover, oil pan and accessories that shouldnt interfere with the new heads im just hoping the alt and a/c mount bolt up to them.

Now for the questions

i no custom length pushrods are needed but has anyone figured out a definate length and a good place to get them. Again im going from a 3.1l to hopefully the 2000 heads.

Next question is which head gaskets are used? I have a new set of headgaskets for the 3.1l and im thinking those wold work but i wanted to double check.

and lastly how has everyone modded the temp sensor to work? Is there one spot where the 3 wire sender could be put?

Thanks for any help its greatly appreciated.

[Superdave]

the 3.1 aluminum heads and the newer gen3 heads have the same accessory bolt pattern/location so if it's bolted to the 3.1 heads now it'll fit the 3x00's just fine.


www.pushrods.net is one of the best places to get them, length can vary but typically you'll want the new ones to be about 6.25" and 5.95", 5/16ths diameter. regular ball end. It would be best to buy a pushrod length checker and do the measurement yourself as there are some variables involved.

I would use 3.1/2.8 Camaro/Fiero/S10 headgaskets. They are thinner and will bump up the compression. it will also improve your quench.

the 3 wire temp sensor from an early 3100 will thread into the 3x00 LIM and work perfect. Just make sure to grab the pigtail as well. black is ground, green goes to the gauge and yellow to the ECM.


Good Luck!

[mtownfiero]

Thanks sounds like its pretty straight forward. Just wondering though what the variables about the pushrods are? If all stock 3.1ls use the same lifters and the heads for the swap are the same, would the amount of wear on the motor change the length they need to be? Just curious. Thanks again, andrew.

[IsaacHayes]

1996 Beretta CTS is 3 wire. Same part for a 95 dodge neon too... lol don't ask me why I know this. Pigtail can be used from a TPS too, and some other pigtails such as A/C etc that are 3 wire.

You will need to swap to the new style P/S pump as the gen2 is too big for the intake... errrrrr wait Fiero doesn't have PS nevermind.

Carry on.... alt might fit... I think you can mod it or something. Or get a 94-98 grand am / beretta alt.

[Superdave]

Thanks sounds like its pretty straight forward. Just wondering though what the variables about the pushrods are? If all stock 3.1ls use the same lifters and the heads for the swap are the same, would the amount of wear on the motor change the length they need to be? Just curious. Thanks again, andrew.

block deck height, headgasket thickness, cam base circle (stock VS aftermarket), heads (stock/shaved) and i think that's it... you have some give in the lifters. Those measurements have been used on alot of hybrids and nobody has had a problem.

[ghrarhg]

Don't forget the difference in rockers between the gen 2 and 3 is the main reason for requiring the new pushrods. My pushrods were way longer than everyone else's for my hybrid. So I wouldn't say go with 6.25 and 5.95. You really should measure. Especially if there is an aftermarket cam involved.

[mtownfiero]

cam is stock but how do i measure for the new pushrods?