93 Grand prix 3.1L mpfi (what can i do?)

[93grandprix]

after my grandfather accidentally sold my shadow project car (it was pure crap) he felt bad and gave me his grand prix. im excited because this is a much better car than my shadow. now my question is, what to do with it, i have a 3.1L engine so 128fwhp isnt that much, is there anyway to get some decent power gains (more than 50hp or so) i know the basics, cold air intake, exhaust, spark plugs, timing. but is there anything else i can do? is there a governor on this car?. I'm sorta in a build off with my friend who is getting a similar car to mine, we can only use N/A and no engine swaps. what about torque steer? will this be a big problem? im also worried about how my trans will hold up. I have not gotten to drive this car on the street being that im not 16 for another 3 months, so i cant say too much about what i want to limit the power too. basically i just want to be able to have a nice drivable car, and maybe show some ricers how a real car runs.

which brings up this slightly off topic issue. because i know somebody might mention it being that im a teen. I understand the dangers of speed, I love cars and dirtbikes and anything else that goes and because of this i understand just how easy it is for things to go wrong. i hope to be the exception to the teenage stereotype by being a responsible driver and keeping the racing to the strip.

[montess408]

well if you have to keep the 3.1 that will limit you in your quest for power
if your motor is in good condition i guess a under drive pulley would be a good place to start and a cam (crane 260) and roller rockers and ports & polish the heads and intakes bigger throttle body and a chip for all the new mods with all that done (big money spent ) you will have a stout 3.1 but i still think you will be making less power than a stock 3400 just somthing to think about !

[Mr_Efficiency]

you'll see it again and again on here 3X00 top end, Find a 2000+ car with a 3100 or 3400 and take the upper intake manifold, lower intake manifold, heads exhaust manifolds and the timing cover. Power steering pump is needed as well.

The 3X00 motors use 1.6 roller rockers compared to the 3.1 with 1.5 non roller. If you use the 1.6 rollers you need custom length pushrods. to keep things cheap and simple and avoid the custom length pushrods you can A) use your 1.5 rockers or B) find a 94-95 3100 they have 1.6 non roller rockers. This will give you the bigger ratio without custom pushrods, only down side is you dont get the rollers.

Also a 3500 upper intake manifold will bolt righ onto the 3X00 lower intake and it flows a bit better than the 3X00 one.

Like i said this swap is all over this forum, do a quick search and you'll find lots of info.

that should put you around 185hp, you could also swap in a 5 speed to get more of that power to the ground since a manual trans robs less hp than an auto, it makes a huge diffrence. I'm currently doing it to my 90 grand prix right now, I have done it to several other cars, its definatly worth it. 5 speed can take more abuse as well.

[93grandprix]

i hear from my friends a manual tranny swap is expensive, is this true? i would love to have a 5 speed. id be happy if i can get 250whp. im thinknig cammed, port and polish, high comp pistons, headers, exhaust, and ecu. im sure there is moreout there im forgetting though. thank you for your advice by the way.

[GutlessSupreme]

Swapping a 5 speed isn't hard, but the parts are hard to find. If you score a parts car in a junkyard, that's your best bet, and could be fairly cheap depending on the yard, but if anything ever breaks and you need NEW parts.. well, there practically aren't any. IMHO, you'll be very hard pressed to get 250 crank hp out of an N/A 3.1, never mind whp, and it will not be cheap.

And you definitely don't have 128whp stock.

[93grandprix]

hmmm it looks like ill have to turbo it, id really like to keep the 3.1 tho just for the reason that if i really want to get a different engine i could just get another car, but that would defeat the purpose of getting the one i have for free lol

also, being that for the moment i have no job and therefore no money, what are some things i can do cheeply or free, not necessaraly performance related. what would be the best way to clean the engine bay?

[bracketracer]

I am probably one of the last "hold-outs" who wants to make HP without the Top-End swap (for now anyway), but the folks above are correct. Trying to make even 200 HP at the crank with a NA 3.1MPFI is very expensive. Even if you went with completely custom light-weight internals, cam, etc, I doubt you'll make 250 HP at the crank with NA 3.1MPFI, let alone at the wheels. Using a power adder (turbo, supercharger, or nitrous, or a combination) would be the only way to get there. That route is expensive too if you want the motor to last. If you are on a budget, then don't even attempt it.

The top-end swap is cheaper and lots of folks have done it, so "tech support" is out there. You are at a weight disadvantage in the Grand Prix from a performace perspective, but they do ride nice! I've always been a fan of that vintage of GP, especially in a 2-dr with the sport package (B4U if I remember correct, or something like that). That would have been my first car if they hadn't cost $18K new. I couldn't afford the payment and "settled" for my Sunbird, but I still love the car!

[93grandprix]

hmm ok, so maybe i should go for a swap loll, what im worried about is the difficulty of say, swapping in a 3400, i will be going to boces for auto tech, but idk if that will even be enough to prepare me for swapping an engine.. about how much do 3400s cost? as far as the grand prix as a car goes, i havent gotten to drive it on the road yet, but i had a choice of the gp and a 1996 cutlass ciera, and i just liked the look of the grand prix more. and for my first years, id rather have something that looks nice than something that is fast. id like not to get into trouble lol.

[LeftVentricle]

I'm an A-body fan, so take this with a grain of salt. You probably should have gone with the Ciera. The 3100 in that car has 160 hp stock, and weighs about 300 pounds less than a Grand Prix. You could do all the same mods with the same end result but be faster because of lower weight. But that's past.

As for the cost of a 3400, you'll have to look on carpart.com or ebay. The price really varies, from as little as $150 to well over a thousand. Really, you should get the cheapest one you can find, regardless of its condition, since you can just rebuild it to your specifications.

[93grandprix]

i might still get the ciera, it depends on which car is worse, i get the one that needs the most work, but it seems ill get the GP being that it needs a head gasket.

As for the 3400 swap, how hard would this be? ill have help but if i can do some of it myself id love to. i know alot about cars but i have little hands on experience

[Barry]

you'll see it again and again on here 3X00 top end, Find a 2000+ car with a 3100 or 3400 and take the upper intake manifold, lower intake manifold, heads exhaust manifolds and the timing cover. Power steering pump is needed as well.

The 3X00 motors use 1.6 roller rockers compared to the 3.1 with 1.5 non roller. If you use the 1.6 rollers you need custom length pushrods. to keep things cheap and simple and avoid the custom length pushrods you can A) use your 1.5 rockers or B) find a 94-95 3100 they have 1.6 non roller rockers. This will give you the bigger ratio without custom pushrods, only down side is you dont get the rollers.

Also a 3500 upper intake manifold will bolt righ onto the 3X00 lower intake and it flows a bit better than the 3X00 one.

Like i said this swap is all over this forum, do a quick search and you'll find lots of info.

that should put you around 185hp, you could also swap in a 5 speed to get more of that power to the ground since a manual trans robs less hp than an auto, it makes a huge diffrence. I'm currently doing it to my 90 grand prix right now, I have done it to several other cars, its definatly worth it. 5 speed can take more abuse as well.

How do the different rockers make a difference in pushrod length? Pushrods between the roller rockers and the normal rockers are the same? I just held them side by side...

[gpse3400]

a few quick things you can do on the 3.1, you can change the rocker arms to the 3100ones. The 3.1 uses 1.5 ratio while the 3100s used a 1.6, and that can be had from any '93-'95 3100 equipped car. you can also get a chip from WOT-Tech that will boost power as well, i'd run a 160 thermostat, you can get that from Summit. And finally if you are have a shop that will help you with this, have the down pipe enlarged from 2" to 2.5". They whould have to chop the flange off and reweld a new curved to match pipe and being that you are in NY you'll want a Catalyst on there. After that you can make the rest of the pipe work 2.5" to the Y. Also The stock mufflers are a real restriction, though I do love the sound....My personal choice is flowmasters or Hooker aero chambers. Aero chamber will be alitte bit quieter. But what ever you do,DONT REMOVE THE AIR FILTER BOX.