What are some cheap yet good upgrades for an engine to gain horsepower on the 85 2.8l auto

 

https://www.thirdgen.org/techbb2/sho...light=upgrades
Don't just skim it, read the whole thing. Some good info here.

In addition to the mods already done (see my sig). I'll be adding Pacesetter headers and a full Cat back Exhaust and Underdrive crank pulley as soon as I get my tax refund.

 

If you haven't already done it...

Anything else you do will make more of a difference if you start with an engine that is running well.

 

Why do you people suggest FULL tuneups and cat back exhausts??

Those both cost $200 +

Not exactly Cheap!

Get a K&N filter.its like $40 and worth every penny.

 

Because most cars haven't had a full tuneup in a long time. You know your car best. If you don't need to do everything, then don't do it! It is a good checklist of things to look at though. I didn't do everything all at once, just a little at a time.

It always amazes me that people who say they want more performance from their engine won't spend the money to maintain what performance they already have.

The stock exhaust is very restrictive, it's good to get more air in but you also need to get it out!

K&N filters for my car cost $25 each. I needed 2.

edit: When I rebuilt my Distributor I found that it was very hard to turn the shaft in the bearings. Instead of spinning with 2 fingers I had to hold the gear in my fist and force it around! I took the shaft out and cleaned it up and it worked like new.

 

The very best bang for the buck (assuming your car is in decent running condition-meaning plugs have been changed in the last year, all spark wires are working, cap and rotor changed within the past year, coil is strong injectors are functioning, etc- the basic stuff) is an aftermarket underdrive crank pulley. This will give you a noiticible little power gain AND a noticable little increase in fuel milage. They are around $50

 

Dont get those so called "Performance Pulleys"
They are worthless and just a waste of money.

 

wouldn't say they are WORTHLESS. they allow the motor to have less drag on the (parasitic loss) and so they do have an increase in power with them. for example. at the track i gained 1mph and dropped .07 seconds off my et buy taking off the power steering. why do you think that most race engines have electric waterpumps and no accesories?

 

Why do you say this? And what do you mean by "performance pulley"?

Everything I've read here on TGO says not to use the Alt. underdrive pulley cause you'll have charging problems. But everyone seems to use the crank underdrive pulley. I know from driving my friend's '91 Formula with a crank underdrive that there was a big differance in throttle response. Much quicker than stock.

 

And for this you would pay $50 for pulley and $20 for new belt?

 

Oh lord. Maybe MAYBE 4-5 at the flywheel, and that's stretching it. After going through your drivetrain, you're not going to see anything going to your rear wheels

 

Depends on what you are trying to do. Obviously some people would.

If you are on a tight budget and just want to drive your car daily probably not. But if you are trying to get all you can from an engine, sure.

 

Yeah but this kid doesnt seem like that kind of person...Most of us here are just daily drivers.

 

I didn't say anything about more HP at the rear wheels did I?




edit: I think we're done with the pulley discusion, don't you think?

 

punk...

 

Nah! I'm too old for you to call me a punk.

 

hey now no fighting

but sure i want it for everyday driving its in great condition, except for a small idle problem soon to be fixed when its warm enough, but i want to gain a little more hp a cheap way and the pulley i dont think is something ill do. The filters i already have.

Though i do have another question this past summer i took out those fins under the filters what is if any of the negatives doing this.

 

hey now no fighting

but sure i want it for everyday driving its in great condition, except for a small idle problem soon to be fixed when its warm enough, but i want to gain a little more hp a cheap way and the pulley i dont think is something ill do. The filters i already have.

Though i do have another question this past summer i took out those fins under the filters what is if any of the negatives doing this.

 

Well im not too sure what fins you are talking about but since you did it last summer and its january you should be fine

 

little plastic flap like peaces that screw in under the filters and seem to block alot of air. I think they deflect water but i dont seem to have a problem with the water

 

didn't pay anything, i just take the belt off the pump. but i was just saying that they help

 

That is what they are. Water deflectors. I took mine out too. With oiled air filters we really don't have to worry about getting them wet under normal driving conditions. A couple people here have commented that they gutted that whole box under the filter. I didn't feel like doing all that.

Firebirds have a different intake setup Slayer. That's why you don't know what he means.


Ignore the dirt. The car had sat under a pecan tree with no hood for 2 years before I got it.

 

another option you can do w/ the air box, i know many have done it on here, including me, is to cut the bottoms right off it. i noticed a lil more at top end.

 

I have installed crank pullys on ever car I have owned that it was an option for it. I say well worth the money. I dont install them tell the car needs a belt, then I'm not waisting a good belt. Out of the 7 cars I have owned, only 1 was not daily driven.

K&N filters, I havent noticed a damn thing installing them. An old board member did a test, they really didnt flow any better then a paper one unless both were dirty. THEN the K&N flowed better. Who keeps a dirty filter in their car?

 

the airbox on my 3.1 is just a small cylindrical canister... and I don't see how the k&n is worth it... like 60 bucks! the recharge kits are expensive too

 

Well I bought mine for $40 and a $6.99 recharge kit,and it made a hell of a difference in my midrange power.

 

when did you notice the difference? as far as I know, you only notice a difference by the time the old style would have been dirty... the k&ns are supposed to stay cleaner longer

 

My OEM filter was not even dirty because I had got a tuneup a few months before.I popped in the K&N right at the autozone parking lot.Let the car idle for a few mins and drove away.I felt the increase right away.Mostly from 2500 RPM up to 5.It was definatly worth the money for me..

 

from what I've heard the K&N's are also waterproof to a degree. On the firebird you should be able to take that canister away, that's what I did on mine and it's fine. Just block the hole in the bottom of the platform that the filter sits on. I did the underdrive crank pully, got it for $20 used and while I didn't notice any power or gas milage increase it was still worth it I think.

 

Explain?

 

he means by having a washable air filter that means he doesnt have to buy 2 new ones every year or so. they are 25$ canadian each for the paper ones where i am, and i got my k&n's from ebay for 30$. i took them out though a while back just to see if the oil was getting dirtier because of the increased flow, and i dont think it is.

also dont oil it up too much or you will wreck your maf

 

I don't remember how much the paper filters were but I know it's $7 per recharge kit for the k&n and I know I can get a damn clean air filter that's all oiled using half the kit. So $8 a year for 2 new air filters that flow better dirty then paper ones will. Also I know the K&N the actually filter is actually protected by metal mesh all around the filter, I dunno about paper ones.

 

No no,I was talking about his pulleys...not his air filter.I was the one with the drop in K&N

 

TomP's tuneup + catback is the first real performance gain you will get.

All this .07 difference on the et is nothing, compared to the .5 or .6 you can get with the tuneup, practice, and a decent exhaust!

 

No Turbo?

 

for $20 or $25 the pully wasn't a big deal to get. Sucked finding a belt but that was my own fault.

 

Hey, with a washable filter.. think of the trees your saving! LOL

I installed an KN&N cone filter in my car and redesigned the intake ducting.

All it really did is change the appearance of the engine bay and make my car put out a lower exhaust sound.

It seemed to slightly reduce the bogginess at higher RPMs, but the filter I replaced this with was kinda dirty anyhow.

 

everyone always does more than just replace the k&n... so they notice a difference, because they change the intake, or do other tune-up procedures at the same time... I've known several people who have told me not to bother getting the filter... just stick with the $6 and replace it 3 times a year....

 

No I just popped in the filter...nothing else done to the car in that time period.

 

maybe one day when I win the lottery I'll buy one of those bad boys!

 

hmmmm. sorry, i went from 13.98@99.2 to 13.89@100.3 by just taking the ps pump belt off the car. i guess that's actually .09 seconds and 1.1mph for free. car is far from needing tomp's tune up and catback. i am looking for every little gain i can get now.

does anyone know if getting the alt. underdrive pulley is bad for the street? don't have a killer stereo, but it's gotta couple of subs. i don't play them loud or anything either. i am getting about 14.5ish volts outta the alternator right now, how much could i expect to decrease?

 

dont get the alt pulley

 

I don't think you will want an alt pully, that will slow down the speed of the alt form about 3x the speed of the engine to about 2x the speed of the engine.
The alt might not have enough relative motion to make enough power to run the electrical system and charge the batt at idel.
It most likely won't be able to make enough power charge the batt, run the head lights, run the heater heater fan, your system and other stuff. It will drain your batt.
My z has a 140amp alt on stock pullies, it makes plenty of power.
I might get an under drive for the V6 but I'm building a rather strange power management system for it too.

 

why are people so worried about the altenator... aren't they electrically contolled by load on the alternator? its only gonna rob a bunch of hp if your battery is low, or your pounding your subs...

same as when you ground the positive and negative terminals on an AC motor, it will hardly move...

an alternator wont do much in normal operation mode..

 

i have a one wire alt. will it affect me?

 

I'm not sure why every one is afraid to use the crank and alt under drive pulley together.

I have been doing it for a couple of years now with no problems. Sure the headlights dim a little at idle, but I don't need to see that far when I am at stop light. Step on the gas and they go back to normal. Also the blower fan is slightly slower at idle, but only slightly. Once again step on the gas and it goes back normal.

If you have a problem running them you may want find out what is wrong with the electrical system and fix it.

I haven't noticed a difference in performance other then throtle respones is better, and my MPG went up a noticable amount. The MPG was the bigest seller for me. I drive at the very least 170 miles a day M-F some times as much as 220 miles. So I really notice small increases in MPG. A 1%-2% improvement saves me a considerable amount over the course of a week. The $50 +the cost of a belt paid for itself in the first 1 or 2 months.

 

it's great that you got that 1% increase, but for most people that's not an easy upgrade, and the benefits don't outway the negative aspects

if your headlights are dimming, then I'd say your voltage is going below 12... can't the computer be damaged by low voltage?

if you really want good gas mileage, can you not put in lower # gear ratios?

 

Does anyone know the actual MPG for the 3.1L?
I know it sounds out of the subject

 

I think its like 17/27..By the way.Underdrive pulleys dont do ****

 

18/27 for automatics... isn't it hilarious that the 5.7 liter only got 1mpg less than us, but a million-time over better motor and speed capability!?

I would have thought our motors were really efficient compare to those giants.. oh well...