7.4L Carb to Edelbrock Pro-Flo Conversion

[97_219]

Does anyone have any information on coverting a stock 1997 Merc 7.4L carb engine to the new Edelbrock Pro-Flo 3551 kit?

I just missed getting a complete Merc MPI system for this engine on eBay for $710. Not sure but think the most of the induction system is cast iron and would add much weight.

So now condidering spending $2500 to convert using light weight pack from Edelbrock. Pretty straight foward, except the modification for the O2 sensor.

Any help on this subject would be appreciated.

[happy]

swapping from a carb engine is a bit of work.. as far as the after market system is concerned.. i really dont know much about it.. except i've not seen a bung for an o2 sensor in marine gas exhaust systems.. I would think the ecm which would come with the system would be programed to read for an o2 sensor..

at 710 bucks for a complete merc system is pretty darn cheap.. considering you will need an intake/ plenium, fuel pump , ecm, wiring harness, plus all the plumbing hardware..

I don't know the intake price off the top of my head but its above 1500 bucks.. and thats just the intake.. (merc prices)..

[97_219]

I agree, it was a good deal. I did not bid any higher because it was for a 454/502 mag engine. I've was considering buying a GM marine crate 454 mag, but cost is 5,800 long block. This is why I thought about checking into an after market Injection system. My 7.4L is hardly used with only 35 hours showing on hour meter.
Edelbrock requires O2 sensor and has given the diagram to modify the riser to access the "dry" exhaust. I am havig problems getting Edelbrock Tech support to get a picture or .pdf of intake port holes. The website never shows anything from that angle. I have Oval ports on the 7.4L not rectangular.
Waiting on them to get me more info.
Thanks for you input. JL

[bowtie]

Just FYI, Edelbrock is supposed to be coming out with a programable (via laptop) system in the near future. You might want to contact them and check it out, but I would be willing to bet it could be programmed to omit the O2 sensors. Of course this would defeat some of the advantages of EFI, but it might be easier to install.

[Taz]

Why not try a 174 marine blower and carb set up for 5 lbs boost. That will add more ponies.