NSW Corvettes

Technical Tips => Post 84 => Topic started by: Slingray on February 15, 2006, 11:32:46 AM

Title: 1984 Engine Swap
Post by: Slingray on February 15, 2006, 11:32:46 AM
Hey guys,

Looking at buying a 1984, I'm giving some consideration to an engine swap, changing the Crossfire to true EFI.

I was wondering on peoples thoughts, has anyone replaced their Crossfire with a true EFI system?

Thanks everyone
Title: 1984 Engine Swap
Post by: BOSCHVETTE on February 15, 2006, 02:54:32 PM
it is very very easy and a good way of getting into a high performance vette cheap
Title: 1984 Engine Swap
Post by: 87Z51 on February 15, 2006, 10:26:06 PM
Bare in mind ,none of the the '84 engine electronics will work with the later EFI be it TPI or LT1 type.
You will need a different ECM  and loom as well as the manifold , throttle body , injector setup.
The ECMs are cheap , the wiring loom go for US$250+ as removed from car.
Can get good performance from Crossfire injection if you know what to do.
Ask Ben73 on this Forum how to make a CF run.
Title: 1984 Engine Swap
Post by: Slingray on February 16, 2006, 04:23:23 PM
Quote
Originally posted by 87Z51
Bare in mind ,none of the the '84 engine electronics will work with the later EFI be it TPI or LT1 type.
You will need a different ECM  and loom as well as the manifold , throttle body , injector setup.
The ECMs are cheap , the wiring loom go for US$250+ as removed from car.
Can get good performance from Crossfire injection if you know what to do.
Ask Ben73 on this Forum how to make a CF run.



Thanks for the reply. My main concern with the Crossfire is that if I were to get it tuned for performance it would start chewing up my petrol bill. I understand the EFI from 1985 on was approx 11% more fuel efficient while adding around 30bhp. I like the sound of the extra 30bhp but to be honest, I really like the sound of going 11% further on a tank of petrol.

When you say a different ECM, do you mean another Corvette ECM from a later model or an aftermarket ECM? Thanks again.
Title: 1984 Engine Swap
Post by: 87Z51 on February 16, 2006, 05:00:48 PM
You will need a later model Vette ( or possibly F body ) ECM  and wiring to suit whatever manifold you are going to use.
Title: 1984 Engine Swap
Post by: ben73 on March 21, 2006, 10:35:08 PM
Although its not a difficult job for someone who knows what they are doing, I don't know whey you would bother.  Don't believe all the rubbish you read about Crossfires.  99% of this is written by people whop have not owned one and are just perpetuating hearsay.
From a functional point of view, it is essentially the same as the TBI system used on MILLIONS of chevy trucks from about '87-95 and is totally reliable and returns great fuel economy.
Sure the manifold chokes it a bit, but it will easily make up that extra 30hp you mentioned with a mild port job on the manifold and a good tune.  A baby hydraulic cam doesn't hurt either ;-)

If you have your heart set on TPI, I'd suggest looking for an '85- car.   If you are set on this '84, I'd say you should give it a tune up and drive it for a while before you consider a top end swap.

I've got one, and I love it because its a bit of an oddball and an underdog, and because most people will say they can't make good power..  

Its a real DIY car.  You can make good power, but its not a matter of opening up a catalog, then your wallet and bolting on some parts.  It is not supported by the aftermarket, so you must make most hi-po bits yourself.  I dunno what type of guy you are, but thats where the appeal lies for me.

Hope that helps some..

Ben.
Title: 1984 Engine Swap
Post by: 86er on March 22, 2006, 12:23:16 PM
Very well said Ben 73
Title: 1984 Engine Swap
Post by: 77CVT on March 22, 2006, 04:21:58 PM
Quote

Thanks for the reply. My main concern with the Crossfire is that if I were to get it tuned for performance it would start chewing up my petrol bill. I understand the EFI from 1985 on was approx 11% more fuel efficient while adding around 30bhp. I like the sound of the extra 30bhp but to be honest, I really like the sound of going 11% further on a tank of petrol.

When you say a different ECM, do you mean another Corvette ECM from a later model or an aftermarket ECM? Thanks again.


My '85 sure ain't 11% more efficient, but I'll bet I chew less fuel then Ben!  ;-)