87 performance mods?

[sgoody43]

Ok guys I just installed a THRUSH full welded 2 chamber muffler I purchased from summit and I am vey impressed with the sound I got from it.  I just wanted to know what other small performance mods I could do that won't  put that much of a dend on my wallet.  I was thinking of a thottle body spacer and maybe a k&n filter and then call it a day.  I forgot to mention I got an 87 shortbed half ton with a 350 fuel injected motor.  I can't go all out because I still have to smog here in CA but I do wnat a little more performance and also a little help on gas.  By the way is a 88 350 basically the same engine because I could find parts for an 88 but 87 is a little harder.

[Captkaos]

87-91/92 motors are identical, so anything you can do to one of those you can do to an 87.

[Blue 82]

Chip it

[VileZambonie]

K&N is a waste of $ Throttle body spacer is a waste of $... So if "dend"ing your wallet is your concern then don't empty it on garbage. If you want any noticeable gains in performance, the "chip" will give you the most noticeable difference without altering the engine's breathability (ie cam, headers, roller rockers etc) by adding more fuel and increasing spark timing. Your fuel mileage will go down.

[team39763]

I think tbichips.com is the place the thirdgen firebird guys go to for their performance tune.  The advertisement even says they can get the same or slightly better mileage than stock.

[Stewart G Griffin]

The other thing that won't cost a whole lot is to install a smaller and/or lighter flexplate.  This will help acceleration a little but i'm not sure it's effect on mpg.

You say you want more performance but you don't want to spend a lot and still be california smog legal? 

You're screwed.  And i don't mean this in a condescending way either.

If the truck does not already have headers, then your only solution is nitrous.  The impression i'm getting is you won't be "getting on it" too frequently so this way you won't have to fill the bottle too often.  But then, we have to factor the cost of getting the bottle refilled---no one ever talks about that aspect of nitrous.

[VileZambonie]

The other thing that won't cost a whole lot is to install a smaller and/or lighter flexplate.  This will help acceleration a little but i'm not sure it's effect on mpg.

  say what? Are you talking about a flex fan? A flexplate won't help you any

[Stewart G Griffin]

i think a lighter and/or smaller diameter flexplate or flywheel will help acceleration at least a little bit.  Less mass to rotate.

Now that you mention it, electric fan(s) as opposed to the crank driven fan will probably help a little too.

[Captkaos]

You don't want a light flywheel in a heavy vehicle, it will hurt you accelleration.

[Stewart G Griffin]

Good point.  Alright, forget about the lighter/smaller diameter flexplate for now.  i need to do more research on this concept.

1) i've been doing some reading and it seems that people switching from the crank-driven fan to an electric report more power and better mpg:
http://www.67-72chevytrucks.com/vboard/showthread.php?t=286800

http://www.youtube.com/watch?v=9OQtVUh1VWk

NOTE: for the video, i was looking for something else and stumbled upon that.  Just as well.

Other things which don't cost a whole lot while raising power and mpg may be:

2) Use synthetic oil.  And possibly 5w-30 instead for less resistance.   i know a small block should take at least 40 weight but.....
Also, run 1 quart low---less drag.

3)If you can change it out yourself, then possibly lowering the diff gear may help performance and possibly mpg.  But be conservative----i.e., 2.56/2.73 to 3.08.

4)jack the front tire pressures to 40 psi, possibly higher.  This may not be good for the tire, but you asked for performance and mpg without spending money which is asking alot.

5)really nitrous is probably the only real solution based on the parameters you've provided.

6)Fiberglass. Not cheap, but in context it is.

7)Roller lifters and rockers.

With all the above, the dollar outlay is not real large and the gains are not too large either.

Really, with a 73-91 truck, the only way to get performance AND mpg is to spend at least 2K. (but really more than that.)

Sorry kid.  But at least you've got a decent, dependable truck that is cheap to maintain.

[VileZambonie]

Stewart I'm gonna have to pick apart your post here a little bit:

As far as the flexplate or a heavy flywheel keep in mind this rotating mass stores crankshaft inertia. Only 1 of three strokes is carried by the power stroke. This energy is necessary to keep that wheel rollin.

The cost of synthetic oil vs conventional outweighs it's benefits in a daily driven vehicle like these trucks. Running 1 quart low is also a very bad idea. Take into consideration inclination, and the job of your engine oil, lubricate, clean, cool, cushion & seal the engine. Most manufacturers are more concerned with oil volume and how quickly we can get it up and throughout the engine rather than it's cushioning effect in modern engines. That is why you are seeing 5w20 as the norm in your Honda's etc. Keep in mind the huge differences in construction, stroke and materials between these engines and an old school sbc.

Numerically lowering your final drive ratio depending on your driveline layout may actually decrease mileage and throw your performance ideas into the toilet. Poor acceleration and longer throttle opening periods will drink much more fuel.

N20 is never economically sound but is a nice cheap thrill.

Rollers are a good idea though for sure as long as it's set up correctly.

Raising your tire pressure will simply decrease the life of your tires and decrease the handling characteristics of the vehicle. For optimum economy run what's suggested on your tire placard if you are using a stock tire size.

Good point.  Alright, forget about the lighter/smaller diameter flexplate for now.  i need to do more research on this concept.

1) i've been doing some reading and it seems that people switching from the crank-driven fan to an electric report more power and better mpg:
http://www.67-72chevytrucks.com/vboard/showthread.php?t=286800

http://www.youtube.com/watch?v=9OQtVUh1VWk

NOTE: for the video, i was looking for something else and stumbled upon that.  Just as well.

Other things which don't cost a whole lot while raising power and mpg may be:

2) Use synthetic oil.  And possibly 5w-30 instead for less resistance.   i know a small block should take at least 40 weight but.....
Also, run 1 quart low---less drag.

3)If you can change it out yourself, then possibly lowering the diff gear may help performance and possibly mpg.  But be conservative----i.e., 2.56/2.73 to 3.08.

4)jack the front tire pressures to 40 psi, possibly higher.  This may not be good for the tire, but you asked for performance and mpg without spending money which is asking alot.

5)really nitrous is probably the only real solution based on the parameters you've provided.

6)Fiberglass. Not cheap, but in context it is.

7)Roller lifters and rockers.

With all the above, the dollar outlay is not real large and the gains are not too large either.

Really, with a 73-91 truck, the only way to get performance AND mpg is to spend at least 2K. (but really more than that.)

Sorry kid.  But at least you've got a decent, dependable truck that is cheap to maintain.

[85shorty496]

Stewart, don't mean to "flame" you, but did you actually read anything you've typed above. a cheap nitrous kit is at least $400 plus all the safeties to keep it from blowing up your motor as well as $70-80 a bottle to fill. If you're prematurely replacing tires from over-inflation, you're not further ahead either. Roller lifters require a roller cam which aren't super cheap. synthetic oil is a good move, less friction = less resistance = more power/efficiency.running a quart low risks eventual seizing of bearings which translates into engine overhaul $$$. optimizing your cruise rpms to make sure you're not lugging the engine is a step in the right direction as well. 3.08 gears work well in a 3 spd auto, 3.42s in a 4 spd OD. If your truck has the snorkel-type aircleaner that draws air from beside the rad and you don't drive much in the rain, you can make a homemade ram-air set-up by cutting the rain guard off the front of the piece that twists into the rad support. carry a spare with the rain guard intact to swap out if it starts raining while you're out. tbichips.com has a list of ultimate mods some of which are fairly inexpensive, like high flow air filter, roller rockers, cooler t-stat. headers also increase the efficiency of the motor and are only about $150 for a set of hedmans. switching from stock exhaust to a headers/dual 2 1/2" system w/ x pipe bumped me from 17 mpg to 21 on my 94 E/cab 4x4.

[Stewart G Griffin]

P.S.
7) Shift kit.   Marginal performance/mpg gains, minimal price.

V, about the flexplate:  As the capt pointed out, in a heavier car it's probably not a good idea.  i did not take that into consideration.

As far as oil, i feel that synthetic has less friction than natural, so we should see a slight performance and possibly an mpg gain.  As far as running it one quart low, i forgot to tell goody that s/he needs to check the oil level frequently.  S/he's asking for perfomance/mpg gains for little cash outlay;  It's difficult.

The rear diff change would need to be very conservative.  In fact, i think 3.08 would be the lowest.  And this would only be from 2.41,2.56 or 2.73.  It might not kill mpg.

Every engine should have roller rockers+lifters, i feel.

As far as the front tires, yes i realize this puts extra stress on them, but again s/he's wanting improved performance/mpg without spending any money(what's wrong with this picture?)  And 40psi in the fronts decreases rolling resistance--a little.

i feel his/her only solution(s) are headers and nitrous.  i think there is an NOS "sniper" kit available for $420.

Either that or trade for an S-10 with SBC.

[Stewart G Griffin]

No, please feel free to flame---i'm trying to learn.

i did not know it costs $70-80 to refill a nitrous bottle?  That's the aspect no-one talks about.  Is this Canadian or american dollars?


So anyways, in conclusion, i feel that with 73-91 trucks, or for  that matter ALL full size trucks, the only way to get performance and mpg is to spend some money (turbodiesel).

[nativetexan]

what about a serpentine conversion. Or take the fan off the crank and switch to an electric fan. Or both. They both reduce power loss. While your at it, take the chain and gears and go back with a 'quiet' gear set. that reduces power loss also. I still think the chip is your best bet. I recently checked out tbichips.com and that dood has alot to offer. email him and see what he can doo. That's probably gonna be the most bang for your buck if you don't want to get into the engine.