Hey guys, posted this here, cause not to sure where else to post it! Anyway...

I have saved a little money through the process of getting married and buying a house, and I want to put a little into the Bird. I have a 91' with the mightly L03. I have it narrowed down to one of two things. Keep in mind I have a cat-converter that rattles at stop light (drives me insane!). So....

a) Zexel posi with 3.73 gears

or

b) TES headers w/ 3" Catco cat.

I would guess the posi would be more of a sotp difference. But the headers and cat would fix the rattle, also give it a little nicer exhaust note.

What do you guys think? Thanks for the replies in advance, any reply! Oh yeah, already have the 3" catback, thanks!

 

Start with the exhaust.

That much gear will make the car able to pull stumps, but probably not be able to even go the speed limit on the freeway. It certainly wouldn't have any power above 60 mph or so. It's too much gear for an engine with as little RPM capability as the L03 has.

After the exhaust, get a cam and a set of non-TBI heads such as 305 TPI heads; then it will be ready for the gear.

 

Exhaust before, say, 3.42 gears as well? I am on the fence as to the gear ration....

 

3.73 is as far I'd would go with a 305TBI. I;d prefer 3.42's as they're a nice compromise between cruise-a-bility (not a word) and take-off-a-bility (also not a word).

Oh - if you already have a 3" catback then get the headers and cat. Boom! Exhaust is done, finished, over, fin. It's nice to get to say "I have full headers back exhaust".

 

anyone else have an opinion? how much of a sotp difference will I feel with either mod?

 

I have 3.73's in my current car (LG4 T-5 Z) and it is a poor match for the RPM range, just as you get on it your shifting because you ran out of power band.

I definately recommend headers and exhaust first, then a cam and upgraded heads .... THEN 3.73's, if no cam go with 3.42's as mentioned, because you just won't have the RPM to take advantage of the shorter gears.

 

I agree with the rest, go with exhaust first. There's a reason most people modify exhaust first and that's cause it always makes the most sense dollar, performance and satisfaction wise.

 

Exhaust first.

I have 373's in my 84, and it is a good match for that car (see sig below) but it spins 6000 rpm as easy as pie.

If you get that engine breathing easily then you can swap some different gears in there, but get it breathing right first.