changing crossfire C4 to carburation

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I need just a little advice about changing from crossfire fuel injection to a carburated engine on a 1984 C4.
The intake and carburator shall be Edelbrock. My question is I have been
told that I can continue to use the HEI distributator, is this possible? If it is I only have to change intake, carb and linkage, is this correct also.
thanks for any help.
Art
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been there, done that...
actually you will be getting away from most of the computer and emissions. (hope you know where you can get an inspection) you will be changing a lot more than just the HEI distributator, intake, carb and linkage. the stock exhaust manifold is set up for the smog pump and the cross-fire. you will have to modify the exhaust manifold, plugging up a number of holes that will no longer be needed. you will also have hood clearance problems with the intake and carburetor and will have to use a short intake. the breather element will have to be very short. Edelbrock has a short breather for their carbs. it not that good of a breather though, but without a custom made breather, its the only choice. an Edelbrock carb is really the only choice you will have. a Holly carb is too tall... (you do have the choice of adding a hood-scoop) you will be better off keeping the crossfire. I found out later that my cross-fire could have been modified to become better then it was. I wish I would have gone that route !
g'luck
--
'Key
=====



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Thanks Key, but my options are very limited, the crossfire intake has a crack and must be replaced, I replaced the exhaust manifolds a long time ago with short headers and have removed most of the unecssary stuff. Edelbrock has recommended a #2101 intake along with a #1406 600 cfm carb which they advised will fit under my hood without alterations, I enjoyed the cross fire, but do not have a lot of options. The ignition is a major problem with me as I have never 'messed' with them and cannot find any procedures on how to change over to carb from cross fire.
Thanks for any additional assistance you can offer.
Art

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Just have the manifold welded. Would be a lot less money and work.
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You can buy crossfire intakes at swap meets,
I'm sure if you do a Google search, you can find one. Also, call Jones Enterprises @ 570-644-0777 in Coal Township, pa.
He had an 82 Camaro, with a spare one.
I hope this helps.
RK

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Art wrote:

intended to provide any performance.
You'll need some scheme for advance (vacuum and/or centrifugal), like the earlier HEIs had. -- pj
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Thanks pj, are you recommending changing the entire distributator to an earler one (example a distributator from a 78 'vette that had carburation) and add vacuum advance unit to the engine. Will the tach and other instrumentation work if I do that? What else must be done to accomplish the changeover?
I appreciate any additional insight you might be willing to give me.
Thanks, Art

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Art wrote:

Suggestion is: don't do this. Instead, take a look at Wayne's post and build a shopping list to restore the Crossfire.
Also, try a post for Crossfire improvement suggestions in the C4 Scan and Tune Forum: < http://forums.corvetteforum.com/zeroforum?id >.
Maybe I'm reading the situation wrong but, think you're looking for 'off-road' experience where emission control is not an issue.
I think the carb conversion will make for more complications, more $$, less rear-wheel horsepower, and more fuel consumption. OTOH, a new cam, redoing the hood profile to accommodate a larger intake etc. etc.
There is a tach signal from those old distributors but it's a pulse from the 12-volt module. Your current tach signal comes from the ECM and it's a digital signal.
Another distributor issue is the weak advance curves in the 77-79 HEIs. You'd be starting out from square zero, building an advance curve. Ten years ago, I rebuilt my '79 HEI -- mess of red oxide inside and lower end had suffered a lube failure. Expect most salvage distributors to look the same.
hth
-- pj
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Art wrote:

http://tinyurl.com/2dz3yg http://tinyurl.com/22ehsm http://tinyurl.com/2bx6p9 http://tinyurl.com/2786hd http://www.crossfire.homeip.net/cftest/policy.asp
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Carb/intake won't fit under the hood. Your HEI distributor won't work at all. Fuel pressure is too high. 4+3 manual won't work. Converter lockup won't work. TV cable won't work. Cruise control won't work. Not U.S. emission legal. Less power. More gas.
If you've given up on the Cross Fire, have you considered upgrading to TPI fuel injection?
Raid a junkyard Camaro or Firebird (look for '85 or '86) for all the hard parts. Add a PPI wiring harness, new injectors, and a booster fuel pump. The existing sensors in the car will wire right in (even the wire colors are the same) and the new computer will work with the transmission.
You'll get more power and better gas mileage. It should be legal just about anywhere (not sure about California). Parts match and it will look stock.
Or, perhaps a 2-barrel TBI intake from a late model small-block would adapt. It would be better than a carb.
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wow, seems everyone is against it but i have seen several here in the southeast that appear to be running fine with a carburator. I may have to strip out the dash and replace with standard gauges, but the trans should perform ok, i guess what i am doing is dropping back 4 years in technology but necessary to keep it running. I have seen many cars built with a 350 and running without a lot of electronic additions, the '84 was a very primitive computer and most everything can be bypassed i think. I don't think I have any alternative ways at this point.

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Actually the '84 vette was state of the art for it's time. The rest of GM's line-up was sporting closed loop carb systems.
Conversion to carb can be done, but it requires an awful lot of bypassing and removing of controls. As one poster commented, the transmission is an electronic 700R4. It has no provision for a TV cable as used on other GM models.
At this point with the ECU pretty much having to be by-passed, I have no idea how it would effect the LED dash or the rest of the instrumentation.
Man, I wouldn't want to attempt what you want to do.
Good Luck!
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All this over a crack in an intake manifold... are you nuts?!!
Art wrote:

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This is a multi-part message in MIME format. --------------050200020905060406080304 Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit
CardsFan wrote:

--
Ric Seyler
Online Racing: RicSeyler
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Hey, all you can do is point out the pitfalls and disadvantages to the fellow. I agree that a cracked manifold doesn't warrant what he wants to do, but he seems to have his mind set on it. In effect what he'll be doing by completing this "retro-fit" is reducing any market or intrinsic value of the car to nothing,.... plus he's going to spend a couple thousand in parts & labor to arrive at this end result.
Not to criticize, just my opinion.
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Pitfalls as follows:
Modifying the transmission detent cable, and making a bracket.
Changing over to a HEI distributor, providing he has the clearance.
Wiring issuse, Codes setting for missing components.
Emissions, my daughters and grandchildren breath the air hr will mess up.
Cam issues, i.e..: Stumbling, hesitation and all that good shit.
Gearing, the rear is most like lower than a carbureted car.
I'm too disgusted to go on and tired.
RK

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I would be all over a conversion if it were my car. where you going to find the parts for a 1984 crossfire (something that was very limited production).
Other poster said this car has a electronically controlled 700R4...is this true on a 1984 model car? Since I'm not a corvette nut I don't know but that does not sound right. You have the lockup converter controlled by wire but I don't think this thing shifted by wire (correct me if someone knows for sure)
Unless you have a pristine car and want to retain the stock engine.... I would basically trash the fuel and intake setup. Install an old school HEI distributor (like came on a 78 z-28) you can buy a good rebuilt unit from NAPA. Find out what low profile dual plane intake and carb setup + air filter will clear the hood. Do away with computer controls....etc... Now this based on living where emissions controls are lax or non-existent.
If you live where you have strict emissions controls... I would look for a good tuned port motor out of a later model z-28 to swap over.
There are a number of companies that make all kind of stand alone wiring harnesses for projects just like this. Of course you would have to know how to work on the car and have good basic mechanical knowledge of the vehicle and any donor vehicle.
All around road manner and good power....I would be looking for a tuned port setup to use (GM OEM Stuff) not aftermarket. I would look to buy a complete engine assembly out of a wreck.
Maybe something out of a 02 Z-28 or even a LT-1 engine out of caprice or road master would be good.
crossfire to me would be a pain in the ass to screw with, given the opportunity to get a new motor with a lot better fuel injection setup.
Was a crossfire not something like to mini-throttle body type injector setups. I would go with a more modern fuel injection setup any day over crossfire. You can buy entire engine assemblies + ecm + wirining harness for $1,500 or so.
Seems to me that even the corvette used a transmission in the 1984 year that worked of either kickdown cable or TV cable. Unless the 84 has the odball trans mount setup I would change that too, and go with a more modern version of the 700R4 with TV cable. Does the 84 have the oddball trans mount setup?
If under strict emission controls, you better check the rules on engine swaps in your area to make sure what you can do in order to pass emissions / inspection, othewise you may be up the creek.
If you get a complete engine assembly then get the wiring harness and the ECM. Othewise you'll need to obtain an ECM and can use a wiring harness from painless.
Swapping all this would not be an easy job. Don't know if that car had an "electronic" dash... and if so does the ECM have any direct control over the gauages or inputs into the dash. This would be a big job to tackle, I would certainly do some research, espically if you will have to pay someone or even do it yourself.

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I'll bet the whole intake and throttle body assembly from a late model small block TBI engine would work with little modifications. It's basically the same as Cross Fire EFI, except both injectors are in one place instead of opposite ends of the manifold. Probably uses all the same sensors.

Beware of the Caprice LTI's. Not all are 5.7L. They're all visually identical, so check the casting numbers.

It's a twin 1-barrel throttle body EFI setup with a throttle body at each end of the manifold. It's really not a bad design. I had an F- Body with a Cross Fire 5.0L and it was very reliable.

There's a '94 Z28 LTI engine on Craigslist in my area for $1200 - complete. It's in a running car so all the wiring could be recovered if someone took the time to do it. That takes a while but saves the $500+ for an aftermarket harness.
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The ECM fired the injectors at different times,
But, I think the one TB's wires can go to one injector, and the other to the second injector.
Still a hack job, but plausible.
RK
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