I know this has already been covered at some time,but I am new to this forum. I have an 84, stock,no cats,forced cold air intake. Car runs 8.64 in the 1/8 mile. I live down south close to sealevel. If I removed the crossfire and went to a carb can I expect any better performance? I have another crossfire manifold that I have ported, but if I am going to the trouble to install a new manifold whay not go to a carb? Any thoughts? And no we dont have to pass any emision tests in alabama. :seeya

 

It'll go faster with a carb than the stock set up. Probably no any faster than with a GOOD ported manifold. I ported the bejezzus out of my manifold, and I think I've maxed out the intake side of the engine. The heads, cam, and exhaust seem to be the bottle necks, now. You can get more intake air capacity for less money with a carb, but it doesn't sound like it's there, yet. You can't beat electronic (even crossfire) injection for drivability and fuel milage. That is just MY opinion. Of course I could be wrong.

 

Hey, CFI-EFI do you drag your vette? I would love to hear from some other crossfire owners that race, what kind of times are you turning? :cheers:

 

You can probably get more top end power with the carb, but you loose a lot too. EFI is here to stay. Even if the Crossfire es an early EFI, it is still better than a carb in my opinion.

Have you seen this site? It's all about Cross-Fire and you can learn a lot about the cross-fire, and how to improve the performance.
http://www.crossfire.webhop.net

 

Hey JoBy that is one sweeeeeeet vette you got there! You cannot still be running the crossfire with that super charger????? That is really trick! I have the new manifold hogged out, took the egr off of it, what about the swirl plates, remove? I have been to that site a hundred times but have not been able to register. :cheers: this buds for you! :seeya

 

CrossfireVM:

YOu might want to look back a couple pages on the C4 General Discussion Forum. CFI vs. TPI was covered quite extensively(and I apparently appalled some because I didn't say CFI was a good setup, apologies to those people) and there is some good info there.

Bottom line, it's about what you want to do. Making a motor run well is all about building the proper combination. You can have a huge cam and stock exhaust/induction system and it'll probably run worse than stock configuration(Although have that nice 'drive in cam' sound:)). Similarly, you can have the best intake with the incorrect head/cam combo.. The motors that some people build, which are *very* fast for very little money are the ones where people know how to match engine components together. It's a gift for some, the luck of the draw for others.

I've invested about 2500(maybe 3K including *everything*) in my '84, choosing carefully the engine components that would work well together. That's very difficult to do as the CFI manifold is so restrictive once you do other mods to the motor(the intake runners a tad more than half the size of those on the head). I've turned a *best* time of 13.39@104.**mph in my '84(cool night, near perfect run, street tires); under 'normal' racing conditions(if there is such a thing;)) It'll run 13.5-7@101-102mph. Some may say that's *fantastic* performance for an '84 and I agree... for a CFI setup. In fact, I only know of one other '84 with the CFI intact that has turned a better time than 13.39. That was some guy from Canada(12.92, but he had 3.73 gears), under more than ideal conditions(meaning calculated below sea-level air).

If I would have yanked the CFI off to install a carb,(and was willing to sacrifice 25-27mpg at 80mph, great throttle response, and the fact that my car runs pretty good with the CFI on, worth bragging about to anyone really;)) put 2500 bucks in the motor, building a combination to suit that induction system, I'd probably be running low 12s at 110 or so mph. Again, I'd lose a lot of driveability(probably 15mpg highway) and it's difficult to get anything other than a Performer 4 barrel intake to clear the C4 hood (Performer RPM will not).

So, my recommendation? If you want to do more than getting your '84 to run low 14s or high high 13s on a good night, look at 1)getting another car or 2)be prepared to spend some bucks. That's my .02 and I'm speaking from 10+ years of modifying my '84. I love the car, will never sell it, but it is what it is, and that's a mediocre running car(by today's standards) with a compromise for an induction system. I'll end this post with something Dave McLellan said when I asked him many years ago what I could do to make an '84 fast. He surmised, "Yank the Crossfire off." :):)

 

I saw a few posts here about a guy who was taking a 4 barrel manifold and mating the CFI lower plenum to it, so all the stock throttle bodie parts still fit on it. Aparently it was a really good mod that woke up the CFI engine as well as a super ram can wake up a TPI.

You might want to check it out, he was selling them for around $300-400 I think.

 

I second this suggestion. Another option would be to use a single 4bbl intake and a larger throttle body. A third intriguing option would be to get an Edlebrock dual 4 bbl intake and put the throttle bodies on it. Either of the last two should work with the stock computer. The dual 4 intake will require a thin adapter for each throttle body and a linkage change. Now that would be a unique intake. setup.




[Modified by AquaMetallic94LT1, 6:31 PM 12/18/2001]

 

Keith,
You ARE kidding , aren't you? Do you recall the 7 or more e-mails we swapped back and forth between 12/2 and 12/9? You even sent me pictures of your air scoop. YES, I do "drag my vette"!
Jim

 

:yesnod: Yes I am! You can see LOT'S of pictures on my site.
http://drive.to/joby

Engine is compleatly stock exept for modified swirl plates. I removed all emissions stuff and installed a true dual exhaust with headers and x-pipe.

I measured close to 300 rwhp ( at 10 psi boost )

G-Tech numbers:
1/4 mile 12.73 sek 116.3 mph
0-60 mph 4.73 sek

 

Sorry CFI i get all these names and addresses confused! I was also thinking about trying to match the throttle bodies to a deul intake that would really be cool! I am not trying to set any speed records, I hvae two friends that also have vette one 86 one 95, just want to beat them! On a good cold night I am about 3 tenth away!Thanks for all the post an the info! :seeya
that is untill they start tinkering with theirs

 

Ditto!! if you come out to this site, you will see why you should keep you CFI. Hope to see you there. :)

 

[QUOTE]CrossfireVM:

and it's difficult to get anything other than a Performer 4 barrel intake to clear the C4 hood (Performer RPM will not).

The Performer Rpm does fit. I've ran it along with many other intakes while sorting out different combos. The Rpm works best with a 1 inch spacer, however don't think about running an air cleaner, it won't fit. :cheers:

 

Hey 11sec84, how hard was it to swap in the t350? :chevy

 

Wow awesome car JoBy!

 

Thanks! :D