Speed density on 5.0, whats that mean?

[97cobraheaven]

ok guys, i have a potential trade for my car. It is an 87 GT. Very clean car, mostly stock with exhaust and new headlights and fresh paint. First question, what is speed density and how is it different from a mass air? how do you convert it over? Is it beveficial to convert? Also, what do you guys think is a fair asking price of cash to go along with the car? $4k, $5k? This car has a lot of miles but the guy is a fellow stanger and owns an 03 Cobra, an LX 5.0, and this GT. So i take his word that it is a great running car with a few things that are normal with that old of a car. All opinions are welcome

here are some pics

 

[94CobraPace]

Speed density cars do not take mods well. They run off tables in the computer, not the MAF meter voltage to run. Yes it is benifical to convert to MAF meter and AL9 computer. Will need a AL9 computer, maf meter & wiring. Ford sells a conversion kit, but is pricy, like $500 or so. You can put it together cheaper yourself. No expert on the SD cars.

 

[AZSnake98]

Yea what he said. You need the harness... MAF obviously... and an A9L computer that can be taken out of a 90 or newer 5.0.

P.S. Why would you trade ur 97 cobra for an 87 GT?

If its financial then I understand 100%.


P.S.S. I wouldn't give him more than 3500 in EXCELLENT condition. Im selling my 91 GT already mass air, headers, chip, full exhaust, 17" cobra R's 150k miles for 4300... and it is CLEAN. Just a heads up.

 

[Diabolic]

You can keep a car speed density as long as the lobe seperation on the camshaft is 114 or greater. You can still do the exhaust, heads, roller rockers, and intake without any problems with speed density. You can even get a custom speed density friendly cam for less than a MAF conversion, but you will be stuck with the stock injectors.

 

[reddog4063]

correct me if im wrong but stock for stock the SD cars were faster than Mass Air. But when modifying the car you will 100% need to switch over...there are many companies that sell the entire kit to switch over.

 

[SKMCOBRA]

correct me if im wrong but stock for stock the SD cars were faster than Mass Air. But when modifying the car you will 100% need to switch over...there are many companies that sell the entire kit to switch over.

No I don't think so. I owned an '86 5.0 with SD (they all came with it thru 1988, unless it was from Cali) and it didn't feel any faster. It was an auto vert with the following mods: MAC CAI, Flowmasters, Magnaflow X-pipe, and JBA shorty headers. It was a low 15 car. I don't know why you'd want to rid of the Cobra for a much slower car? Unless this car is stroked it's going to feel like a pig compared to the snake. I know mine did and that was going from a bolton 5.0 to a bone stock '97 Cobra.

 

[Diabolic]

No I don't think so. I owned an '86 5.0 with SD (they all came with it thru 1988, unless it was from Cali) and it didn't feel any faster. It was an auto vert with the following mods: MAC CAI, Flowmasters, Magnaflow X-pipe, and JBA shorty headers. It was a low 15 car. I don't know why you'd want to rid of the Cobra for a much slower car? Unless this car is stroked it's going to feel like a pig compared to the snake. I know mine did and that was going from a bolton 5.0 to a bone stock '97 Cobra.

The 1986 did not use the E7TE head castings, and had a smaller opening at the mouth of the intake for the t/b. In 1987 Ford swapped to the E7TE castings that all the 5.0 mustangs used from there on out. The same holds true for the opening onnthe intake manifold. The speed density cars were faster than their mass air equipped counterparts if both vehicles were stock. I believe this was due to the smallish mass air meter that the air had to pass through before entering the t/b. It became some what of a restriction, but once the meter was upgraded then that went out the window.

 

[SKMCOBRA]

The 1986 did not use the E7TE head castings, and had a smaller opening at the mouth of the intake for the t/b. In 1987 Ford swapped to the E7TE castings that all the 5.0 mustangs used from there on out. The same holds true for the opening onnthe intake manifold. The speed density cars were faster than their mass air equipped counterparts if both vehicles were stock. I believe this was due to the smallish mass air meter that the air had to pass through before entering the t/b. It became some what of a restriction, but once the meter was upgraded then that went out the window.

I know the 86's were only rated at 200hp verses the 225 of the 87-93's, but that 25hp isn't going to make up much stock for stock with a 305hp Cobra. It was night and day difference. I have a friend with a 93 5.0 Cobra and his is finally faster than mine but he's put a new intake, heads, and cam to get it there. It also gets horrible gas mileage and isn't that streetable anymore...at least not for highway or drivers over 20-30 miles.

 

[97cobraheaven]

well i am must lookin to get a project car and some cash to come along with it, no straight trading here! just curious about speed density and if they were worth the hassle

 

[97SVT#777]

My second mustang was an 87' GT with T-Tops, new stock long block from ford, with b-303, full exhaust, and 4.30's and it tore up a lot of h/c/i cars. It did have a small driveability (surging) issue but it wasn't worth switching to mass air.