Visual check-is it a 4.6-5.8, 2bbl-4 bbl?

[jakerock]

I picked up the '91 CV I bought on eBay kind of in a rush, drove home before I had much chance to check it out carefully. During a quick test drive in noon-hour heavy traffic, it ran, shifted and braked okay, and the seller has 100% good eBay feedback; so that was enough for me to take possesion and drive home. It is supposed to be the 5.8 HO V8 with a 4 barrel. My last two cars were both fuel injected and I haven't seen or worked on carbs for so long I don't know what I'm looking at. In any case, the drive home was about 90 miles and this car was pretty gutless, like a low power family car with a mild passing gear. At home I popped the hood and took off the air cleaner cover.. hmm... doesn't look quite like a 4 barrel to me (sure didn't kick in like one) and I don't see 4 throats like the vintage carbs, just what looks like a couple of fuel/air passages at the front and a couple of shiny black squares behind them in a medium size carb body. Can anybody tell me if there is a for sure way, like maybe even the VIN or something on the car to tell what I've got under the hood, what the 4 vs 2 barrel carb would look like, maybe a picture in an online catalog. At the moment, I'm kind of bummed out, wonder if it was detuned before selling to the last owner who bought it in October or is the smaller engine. Any tips, info, opinions will be greatly appreciated. Thanks

[way2old]

Not 100% positive on the engine size. More than likely it is a 5.0l (302). The carbutetor is the infamous varible venturi. When you want more power, the back shiny things slide back to open the rear for more air and fuel. Worked on those for a while and do not like them. if they are right, they do pretty good though. You can look at the thermostat housing to check size. If it is a 5.0, the lower bolt will be hid behind the timing cover. Good luck.

[jakerock]

Originally Posted by way2old

Not 100% positive on the engine size. More than likely it is a 5.0l (302). The carbutetor is the infamous varible venturi. When you want more power, the back shiny things slide back to open the rear for more air and fuel. Worked on those for a while and do not like them. if they are right, they do pretty good though. You can look at the thermostat housing to check size. If it is a 5.0, the lower bolt will be hid behind the timing cover. Good luck.

I did some more surfing on the internet for info and read the 5.8 liter will have "P72" in the VIN# which this one does, i.e., 2FACP72XXXXX. As far as the "infamous" V V carb, does that mean it's a 4 barrel technically? Can a good Ford tech keep this in nice operating shape, or should I replace it ..and is there a carb that bolts right on without other electronic stuff, or minimal change needed? I've read a lot of the older posts on chip programming, kind of like "Truth Versus Bullshit" replies from one post to the next. I'd like to find out if there is a chip program update or reset the engine might need in case it could have been detuned at sale. I know Ford PI's are not supposed to be a "hot rod" and the design intent is for sustained high speed pursuit and cruising, but.. this one seems too gutless for me: Like eventually I may wind up going 120 and stay there on my way to Las Vegas = no speed limit on some stretches, just Basic Speed Law meaning no faster than safe. Any more info and tips greatly appreciated.. and Thanks!

[radioman2002]

Pre 92 CVPI could come with 5.0 EFI or 5.8 2bbl venturie computer carburator. I would have to look up the vin code for the difference, will post later. The venturie carb sucks, unless you are having problems with it, don't mess with it. The Michigan State Police tests for that year showed that the 5.0l was quicker off the line 0-60 and 1/4 mile, and only had a 5 mph difference on the top end. Those 5.8 cars are great if you want to tow, lots of tourque, can pull a house down, but very poor performance, the engine is basically a truck motor. If you are get a 4-bbl manifold from a pre-85 car for the 351 or 5.8 (not a 5.0)and change it,(modern 4-bbl manifolds are good too) put a good Holley 4-bbl and the car will rip. BTW the 5.8 Police car was never a real good performer, the cid was there to meet bid specs on a Police car with at least a 350cid engine. In fact in 1992 Car and Driver requested a Ford CVPI for testing for an article and Ford declined stating it was comming out with a new Police car the next year. They new it was a POS car, and didn't want the embarrassment against Chevy's 5.7l Semi-EFI.

[jakerock]

Originally Posted by radioman2002

Pre 92 CVPI could come with 5.0 EFI or 5.8 2bbl venturie computer carburator. I would have to look up the vin code for the difference, will post later. The venturie carb sucks, unless you are having problems with it, don't mess with it. The Michigan State Police tests for that year showed that the 5.0l was quicker off the line 0-60 and 1/4 mile, and only had a 5 mph difference on the top end. Those 5.8 cars are great if you want to tow, lots of tourque, can pull a house down, but very poor performance, the engine is basically a truck motor. If you are get a 4-bbl manifold from a pre-85 car for the 351 or 5.8 (not a 5.0)and change it,(modern 4-bbl manifolds are good too) put a good Holley 4-bbl and the car will rip. BTW the 5.8 Police car was never a real good performer, the cid was there to meet bid specs on a Police car with at least a 350cid engine. In fact in 1992 Car and Driver requested a Ford CVPI for testing for an article and Ford declined stating it was comming out with a new Police car the next year. They new it was a POS car, and didn't want the embarrassment against Chevy's 5.7l Semi-EFI.

If I have the local "good reputation/nice guys" shop that can work on this swap the manifold and put on the Holley carb, will it work fine right out of the box with manual adjustment - or do the chip settings need to be modified? Also, is the chip only for engine performance or does it set up tranny shift points, maybe a governer setting was added when it went into private use? This car has a kind of odd (to me) shift setup with 1, D, (D) as the choices. The shift points change up waay too soon. I don't need to wind it to the max and am not thinking about racing it at all, but hey.. some reasonable rev's per gear for when I do want to take off fast would be great. I'm in So. Cal. 50 miles north of San Diego. There's almost too many performance resources/shops near here that can either fix you up great OR rip you off with silly stuff. I do have a hard time believing that with current computer performance technology, reprogramming/replacing the chip will "ruin" the engine/tranny. Thanks for the replies. Any more tips and info will be greatly appreciated.

[radioman2002]

The 5.8l engine does not have a computer per-se. It has an electronic ignition module, which no bearing on the tranny, standard fluid drive kind. If you are having problems, change the tranny fluid and filter, make sure you get all the fluid out of the converter too.
As far as I can tell there is no modification that can be done to that ignition module. It has been in use since the late 70's on most of the larger CID engine Ford installed. The early ones were prone to interference from 2-way radios, made for some interesting problems for Police departments of that time.

[jakerock]

Originally Posted by radioman2002

The 5.8l engine does not have a computer per-se. It has an electronic ignition module, which no bearing on the tranny, standard fluid drive kind. If you are having problems, change the tranny fluid and filter, make sure you get all the fluid out of the converter too.
As far as I can tell there is no modification that can be done to that ignition module. It has been in use since the late 70's on most of the larger CID engine Ford installed. The early ones were prone to interference from 2-way radios, made for some interesting problems for Police departments of that time.

Thanks for the reply. Can the ignition module be bypassed and replace with a modified module? I wonder if the ignition module can be reset? The tranny seems to be working okay better after some driving, likely was in storage a long time. I can hear it shift like a typical 4-speed, even downshifts automatically when slowing down w/o OD engaged, just can't manually go to 2nd. OD seems geared so high that engine wouldn't even be working at high mph. There is a hole cut in the front carpet hump where a greasy connector cable was pulled out - wonder if this was a connection to the tranny per radio interference or..? I would like to put a more standard/better performance Holley carb on it, but don't know if it will fit this opening or need a salvaged Mustang or F150 manifold, or if the performance increase is worth it? The V V carb seems to be working okay now also = step on it more and sucks more gas. The #1 performance mod I'd be interested in is a supercharger, maybe turbo that'll fit these. Large to huge increase in HP for the money and only sucks gas when stepping on it, from experience with '89 Taurus SHO with 9psi Vortec added - same mileage as stock, 21-22 mpg if I'm taking it easy. Any other info/tips greatly appreciated.

[RouterDude]

Are you sure it isnt an electronic fuel injected throttle body? The VV carbs when the engine is off, the venturies are fully closed, but the EFITB has open throttle bores where you can see the plates and the injectors are centered in the bore. There are also black covers behind them like you described.

In either case, you can get a Holly manifold, a holly or edelbrock carb and replace the ignition system with an MSD system. http://www.msdignition.com/ The only trick to this whole deal and I ran into it with my 85 grand marquis is the linkages, I could easily create a linkage for the throttle, but there was not a whole lot I was able to do with the trans kickdown linkage, it ran opposite of the throttle throw and I had no way of making it work.

[jakerock]

Originally Posted by RouterDude

Are you sure it isnt an electronic fuel injected throttle body? The VV carbs when the engine is off, the venturies are fully closed, but the EFITB has open throttle bores where you can see the plates and the injectors are centered in the bore. There are also black covers behind them like you described.

In either case, you can get a Holly manifold, a holly or edelbrock carb and replace the ignition system with an MSD system. http://www.msdignition.com/ The only trick to this whole deal and I ran into it with my 85 grand marquis is the linkages, I could easily create a linkage for the throttle, but there was not a whole lot I was able to do with the trans kickdown linkage, it ran opposite of the throttle throw and I had no way of making it work.

The carb interior is kind of a gold/brass color with a rounded raised ring around it. It looks like there are two openings with some little linkages on top, and the two black 1" square openings behind. I'm an old car guy and haven't worked on cars much past 60's-70's models, bought this one for fun, had the SHO done by SHOShop in Huntington Beach. I'm not sure what you mean about the trans kickdown linkage? The transmission wouldn't kick down when you stepped on the gas? That would take all the fun out of it! I wouldn't want to do the manifold/carb swap w/o the trans working too. I'm going to have the local guy that works on my SHO take a look at this '91 P72 and get the lowdown on the carb/manifold/ignition. He does everything from routine maintenance and fix-ups for everyday transportation cars to "from scratch" hot rod mods and is honest and inexpensive.

[RouterDude]

Yep that is definatly a VV carb, I am surprised they lasted that long, I had one on my old 79 LTD wagon, it went into the trash and was eplaced with a $35 motorcraft carb, what a difference that made.

[jakerock]

Originally Posted by RouterDude

Yep that is definatly a VV carb, I am surprised they lasted that long, I had one on my old 79 LTD wagon, it went into the trash and was eplaced with a $35 motorcraft carb, what a difference that made.

The motorcraft replacement worked fine on your 79 with no modifications to anything? I wonder if the same holds true for this '91 P72 351 ci Crown Vic? If just a more standard motorcraft carb would make a positive difference, without needing linkages changed, etc, I'd do that swap right away. The raised round ring around the edge of this one is pretty beat up.

[RouterDude]

No mods at all, 79 was the first model year the VV was used, so it was easy to change it out. All the linkages matched up, and a few of the "devices" I just capped off to prevent vacuum leaks. I needed to replace the air cleaner housing as well, since that did not match up to the plain jane carb.

[radioman2002]

Alright to determine if you have a 5.0 or 5.8 I have my VIN from one of my 91 CVPI, see if it matches 2FACP72G4MX000000 The p72means PD package for up to that year only, after that it was p71. I think but not sure the G is the engine. I can't find my VIN decoder book, probably left it in my investigators kit, in my trunk somehwere.

[jakerock]

Originally Posted by radioman2002

Alright to determine if you have a 5.0 or 5.8 I have my VIN from one of my 91 CVPI, see if it matches 2FACP72G4MX000000 The p72means PD package for up to that year only, after that it was p71. I think but not sure the G is the engine. I can't find my VIN decoder book, probably left it in my investigators kit, in my trunk somehwere.

My '91 CVPI has P72 in the VIN.

[radioman2002]

I believe the P72 was PD and Fleet, the code that we are interested in, is the engine code or the 8th digit. Which in this case is a "G". Best as I can tell the "G" engine is the Windsor 351 or 5.8l engine. Came with the venturie carb. You can pull all that crap off and put the standard 2 BBL or change the manifold and put a 4BBL on it. There is some basic computer control for the venturie, you can lose that when you pull it off.