I have a 1984 corvette, completely stock with 88,000 miles? I would like to add more HP, can anyone help me with some good combinations with a reasonable price range?

 

You might think this is a smartass answer... but it is not.

Unless you have a huge sentimental attachment ot it, the cheapest and most effective way to add HP to an 84? Sell it and buy a newer one. By the time you build the extra HP into it, you will have invested more than it would have cost to go buy a good LT1 car.

 

Change titles.

And I'm a former Crossfire owner. Had one for 11 years. Loved the car, but for what you would put into it $$$ wise to get 300 HP, you can buy an LT1 car that has that already and all the other upgrades that came 10 years later.

BUT....if you're determined to go down this path, it's a Gen 1 SBC, and will respond to all the usual mods. Heads, cam, headers and exhaust, and a hogged out intake will pick up 40-50 HP. Now you'll need more fuel flow and a better ECM. By this time, you'll be deep enough into it you could have had the LT1....and you'll still have an '84 Vette. You'll never get a penny of it back when you sell, so consider the money gone. Forever.

My advice??? Get your Crossfire to run correctly before throwing one penny into it. If it has a lot of miles on it, change the timing chain and gears first. You'll be amazed at how much slack it has, and all that slack is retarding timing and costing you power and MPG. You'll have more power, better MPG, smoother idle, and a better vacuum signal, all of which adds up to a better running car.

Now, replace every vacuum line on the car. I guarantee you have at least one leaking. You should have 15-17" of vacuum at idle. If you don't, something is leaking. Done with that? Now balance your TBI's. Almost nobody does this, and it is CRITICAL to have a correctly running Crossfire. If they're out of balance, one bank of the engine is getting more fuel and air than the other. Think about that for a few minutes in terms of power...4 cylinders are down on power if they aren't PERFECTLY balanced.

Still with me? OK, now a full tune up. Plugs, wires, cap, rotor, ALL filters, and set base timing to 10 degrees BTDC. Drive the car.....if it pings, either run premium or back it off to 8. Factory calls for 6, but I ran 10 degrees base timing on my (properly tuned) Crossfire, and it REALLY woke it up on the bottom end....enough to suprise most of the L98 guys when the least expected it.

Are we done yet? Not quite. Now test your fuel pressure. NOT fun on a CFI. Take your crossover pipe between the TBI's to a tubing shop, and have them sweat in port with a cap, and the corresponding fitting on a 0-15 psi gauge. Now it's easy to test fuel pressure. You should have 9-13 psi according the manual, but a Crossfire isn't happy with anything below 12. If it's below that and you have a new fuel filter, pull the pump out of the tank and check for obstructions in the filter sock, and a split pulsator (replace with fuel injection hose). If you still have low pressure, replace the pump with an 85-91 TPI pump.

Now, assuming your motor's compression was good to begin with, your Crossfire should run like new. And if it was (likely) out of tune to begin with, you'll feel like you just picked up 50 HP.....which you probably did, because that's probably how much you were losing from it being poorly tuned.

How's that for an answer?

 

Totally agree

I really like my 84 --- but --- It is what it is

 

 

I'm very happy with my 84... it runs with the big boys, LT cars aren't a problem. Now... how much power you looking for?

If I could do it all again.... I would of just left it the way it was and not pursued the additional gains. You start with wanting a little more hp and before you know it you become addicted to always wanting more and before you know it you got all kinds of money tied up in it and you'll never come close to getting it back. I'd hate to tell you the amount of money I have invested in mine... at this point I could never sell it without taking a huge loss. But for me its sentimental at this point

This past summer we sold my wifes 84 and I bought her a yellow 94 LT. We love it just the way it is and I'll never mod that one the way I have my 84. She had only 3 requests.... louder exhaust, tinted windows, shiney wheels!... Its nice to just jump in the car and go!

If you want to play around with it a bit and do some of the free mods, then great but my advice is to stop there. Enjoy it for what it is, there's no harm in that and in a few years when you got some extra cash in your pocket... then upgrade.

 

This 84 is going to be mine and in my family for many years. Yes it is sentimental. So I don't mind spending the extra cash every now and then. I will be working on this project over time but I do want to make this Crossfire run with the BIGBOYS. I will keep it looking pretty much completely stock but I want a true sleeper.

So if you would share some info, I would appreciate any friendly tips

 

Define "BIGBOYS". If you mean C4s with >350hp or C5 and later cars, it's not going to happen if you intend to keep the Crossfire intake.

LTx engines are easy to camo...

My stock 330hp LT4


My 500+hp 383ci LT4

 

Exactly right!...
The best you gonna see is about 300fhp with 350 and crossfire intake. But I have seen 400fhp with 383's and still using a crossfire type design intake.

I've been down both roads and can certainly share my experiences with you to help you decide what you wanna do.

But first is you'll have to define "the big boys"... for me I wanted to run with the stock C6's

 

Fast
Reliable
Cheap



Pick 2.

 

That is soooooooooo true!

 

"Big Boys" has changed alot over the last 10-15 years, that's for sure. Your CF powered Vette has less power than most of the manufactures' V6's now (in some cases a lot less). You are starting with a little over 200hp.......adding 100 horses is no small measure (more than head/cam swap) and even with that you aren't going to impress many people these days.......leave it alone and enjoy the handling capabilities, that is the strength of the car, not the HP.

 

Make it into a real beast horsepower wise but keep it completely stock appearing! It's funny as h-ll when you smoke someone with it after they make it a point to have to tell you how slow all CFI 1984's were. No one has to look under the hood and you can still have lots of power with a relatively quite exhaust. It doesn't have to be loud to be fast.

 

Just curious as to what exactly you think you would have to do to a stock 84 to "smoke" someone in even a base C6 coupe.

Keep in mind that he was very clear in mentioning that the cost was a concern.

 

Spray it!

 

This thread is a total waste of everyones time until the OP tells us what his HP goals are, and his budget.

What are the power goals and what is your budget? I believe that you can get to 300 chp for less than a grand. Unlike other posters in this thread, I have done that. How do you get a decent LT1 for an '84 + <$1k?

 

I posted earlier but its seems like so far I've seen around 3 different posts on here that have been deleted. Have no idea as to why since it was all staying on topic.
Anyways... If he is looking into changing the type of injection to something like multi-port he can do it, for just a few hundred bucks.

 

My allowance is $3000. Now what can I do with that. I read an article on a crossfire running 11's for like 2k. Just thought a couple of owners would be kind enough to throw out a few tips since I'm new to corvettes

 

Well I planned on swapping the HP restricting stock CF intake to an elderbrock SY1 with custom lid or a "Renegade" intake from dynamic crossfire solutions. Boring out the TB's adding 90 lb injectors, changing the ECM, Hooker ceramic coated headers, 1.6 rockers dcs cam, borla exhaust with 2.5 pipes, 3.73 gears and maybe a baby shot of nos with help from some of my friends at a machine shop here in San Antonio. Was just looking for some tips that's all

 

Did I miss something? How did out running or "smoking" as I like to use, another car refer to a C6?