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**1987cp** · 07-17-2009, 02:39 PM

More random info on how tiny old musclecar cams were:

The CS560 is even tinier than the CS668, being only 184/189 .050 duration. It's listed for the '64-'67 289 and every 302 I've checked through 1975, when it could be had on the first V8 Mustang II. The CS668 appears to have been introduced for '75 as an optional upgrade or maybe a mid-year upgrade.

The CS674 is listed from the original 351W in 1969 (Mustang) though 1986 in the LTD. Looks like its demise for the 1987 model year was long overdue!

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Specs on the CS560:

Intake Lift (Inches):.230"
Intake Lift (mm):5.850 mm
Exhaust Lift (Inches):.238"
Exhaust Lift (mm):6.033 mm
Cam Type:Hydraulic
Intake Duration:184 Deg.
Exhaust Duration:189 Deg.
Lobe Centerline (Intake):107 Deg.
Lobe Centerline (Exhaust):117 Deg.
Lope Separation:112 Deg.
Product Features:O.E.M Replacement
Overlap:44 Deg.

**andymac0035** · 07-17-2009, 05:46 PM

'85 Mustang GT: Confusingly, lists CS759 for "FI" and CS760 for "TBI".

Got that right......in 85' 5-speed cars were carbed and auto's were CFI (I think, I only cared about the 5-speed cars at the time).

**Pesty351** · 07-17-2009, 05:53 PM

I've got one for you the fella I bought my motor from said he put a stock replacement cam in it. These are the specs he told me are "A new melling MTF-5, OEM replacement cam and lifters for the 77 police 351 HO .450 int lift, .474 exh lift 280 290 duration" Do you find this listed anywhere?

**gadget73** · 07-17-2009, 08:57 PM

Originally posted by andymac0035 View Post

Got that right......in 85' 5-speed cars were carbed and auto's were CFI (I think, I only cared about the 5-speed cars at the time).

Yup. The carb 5 speed cars got a roller cam, same as the 86+. The automatic CFI cars were a flat tappet, should be the same cam as the baby LTD with an HO.

As for the performance listings for the 79 that vanish on later years, I'd blame that squarely on emissions standards. There isn't anything different from a 79 351 to an 81 351.

Also, keep in mind a 1.6 ratio rocker comes in to play. Multiply the lift values by 1.6 to see what the valve actually will see.

**1987cp** · 07-18-2009, 11:01 AM

Originally posted by andymac0035 View Post

Got that right......in 85' 5-speed cars were carbed and auto's were CFI (I think, I only cared about the 5-speed cars at the time).

Not quite ... it didn't list a 4V, and there was no "FI" if "TBI" was indeed referring to the 2V CFI system they automatic V8 cars got. Also, note that the CS759 was the '85 lowpo cam.

What I would have expected to see would have been the CS760 (HO roller) for the 4V and the CS761 (HO flat tappet) for the TBI.

Originally posted by Pesty351 View Post

I've got one for you the fella I bought my motor from said he put a stock replacement cam in it. These are the specs he told me are "A new melling MTF-5, OEM replacement cam and lifters for the 77 police 351 HO .450 int lift, .474 exh lift 280 290 duration" Do you find this listed anywhere?

You know, I was thinking about that ... the specs I found at NAPA seem to be quoting only .050 duration, which is impossible to translate directly into advertised duration (at least with my knowledge level!) ... also, since the CS674 seems to be a symmetrical cam (195/195 .050 duration, .260/.260 lobe lift) it seems unlikely that it would have dual-pattern advertised specs even if the ramp rate were slow enough to have 280 degrees advertised to 195 at .050. Your cam actually sounds a bit like the one Bowman85merc posted about with 204/214 .050 duration adn 280/290 advertised that I had initially thought of as just hopelessly outdated since the still-dated Summit/Edelbrock 204/214 grind has an advertised duration of more like 264/272 or something.

But let's see .... for '77, the LTD, LTD II, and Custom 500 are all listing only the CS674 cam when the 351W engine is specified, at least on NapaOnline. Of course, these are the only three models I'm thinking may have been used for police work, and there's also the fact that inaccuracies elsewhere (such as listing a single-pattern Mustang cam from '89 to '95) suggest strongly that while I've had a lot of luck finding useful info at NapaOnline, they aren't exactly the be-all and end-all of what actually came in different models.

Originally posted by gadget73 View Post

As for the performance listings for the 79 that vanish on later years, I'd blame that squarely on emissions standards. There isn't anything different from a 79 351 to an 81 351.

That sounds quite likely, as '79 (and presumably '80 as well) probably did have much more rudimentary emissions controls that wouldn't be messed with as much by installing an aftermarket cam. I still don't much like the idea of running a 214/224 degree cam like the 1231R with D8 heads, single exhaust, and that tiny 2V intake.

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Here are the specs for the CS760 (the one listed as a replacement for all HO roller cams) that I thought I had posted earlier but didn't:

CS760
Cam Type : Hydraulic Roller
Exhaust Duration : 210 Deg.
Exhaust Lift (Inches) : .278"
Exhaust Lift (mm) : 7.061 mm
Intake Duration : 210 Deg.
Intake Lift (Inches) : .278"
Intake Lift (mm) : 7.061 mm
Lobe Centerline (Exhaust) : 115 Deg.
Lobe Centerline (Intake) : 116 Deg.
Lope Separation : 115 Deg.
Overlap : 49 Deg

**Pesty351** · 07-18-2009, 11:40 AM

For those models were any of them listed as 4bbls?

**1987cp** · 07-18-2009, 11:55 AM

I didn't see any inlet designation on NAPA's site, though it did differentiate between W and M 351 engines (I'm guessing both were available?). RockAuto lists 351-2V, but doesn't specify which engine family!

My best guess so far based on the info present in this thread is that your cam may actually be one of the recommended performance options that were listed through the '80 model year and was at some point colloquially referred to as an "HO Police" cam because it was a common swap for police departments that actually did modify their cars? Otherwise, there must have been one or more factory engine options that simply aren't taken into account in these replacement parts listings. I know, for example, it's a little surprising to think of a factory 4V option in a year when 2V carbs and low compression seems to have pretty much been the order of the day .... on the other hand, it's likewise odd to think that a cam originally introduced in '69 would have still been installed in pollution-controlled vehicles subject to CAFE standards as late as 1986! So yeah, I think there's probably a lot of info I don't have and can't get just by browsing these particular parts websites'

**1987cp** · 07-18-2009, 12:40 PM

Just remembered something else interesting to look up. Without doing a totally exhaustive search, the only cam I see listed at Napa or RockAuto as an Explorer replacement is the CS1533, which is the same one listed for the '95 F-150 and with its 186/197 degree .050 duration, I am assuming to be the same as what actually went into the '86-'91 5.0 Vic. I find this very odd, as information from sources such as jason.fletcher.net showed the Explorer cam as being 256/266 degrees advertised duration to the single-pattern Mustang's 266/266, which *appears* in these catalogs to be listed as 210/210 .050 duration ... therefore, one would expect a direct-replacement Explorer cam to be more like 200/210 .050 duration than the 186/197 tininess of the CS1533.

**gadget73** · 07-20-2009, 07:45 PM

The Explorer cam is indeed the 95+ F150 cam, possible its the 94 F150 cam as well. The 93 had the Vic cam, and I think before that it was a flat tappet camshaft of some unknown specs. In any case, the Explorer cam is definitely not the same as the lopo cam, it has a different firing order so theres no way you could swap them out without problems.

**1987cp** · 07-20-2009, 11:45 PM

Originally posted by gadget73 View Post

The Explorer cam is indeed the 95+ F150 cam, possible its the 94 F150 cam as well. The 93 had the Vic cam, and I think before that it was a flat tappet camshaft of some unknown specs.

I don't doubt that you're correct about the '93 F-150, but both Napa and Rock Auto both list for its replacement cam the CS759, which as we see from the first post above is a flat-tappet that is also listed for pre-roller Crown Vics as well as roller Crown Vics.

UNLESS .... the CS759's specs are listed incorrectly and it is in fact a direct replacement for the factory lowpo roller unit, and it is the CS668 that should instead be listed for the '85 Vic?

Originally posted by gadget73 View Post

In any case, the Explorer cam is definitely not the same as the lopo cam, it has a different firing order so theres no way you could swap them out without problems.

I never said I thought that the factory Explorer cam is the same as the factory lowpo cam. It definitely looks bigger in person, for one thing.

My supposition that the '95 F-150 (and Explorer) replacement cam was more similar to the factory lowpo than the factory Explorer cam is based on the fact that the '85-'88 Mustang cam is generally said to have 266/266 advertised duration, and its replacement is listed here as 210/210 .050 duration. By comparison, the '96-'99 Explorer cam is said to have 256/266 advertised duration, so barring very different ramp rates, I would have expected its replacement to have been very close to 200/210 duration at .050, not the 186/197 of the CS1533.

**johnunit** · 01-25-2011, 08:32 PM

I know this is an ancient thread, but is there any way of figuring out what cam actually came in the cars from the factory?

Specifically, I'm tinkering with a Desktop Dyno type program and the CS674 shows up as making an average of 20-25HP less than the 764, and apparently either one could be in my engine.

**P72Ford** · 01-25-2011, 10:17 PM

I believe you could measure it, but it;d be rather involved.

At the very least you'd need a degree wheel (which you can make), and a dial caliper with a magnetic base.

**johnunit** · 01-25-2011, 10:49 PM

yeah, that's a bit too involved. If I was going to have the cam out I would stab in (at the very least) an H.O. or Explorer cam anyway, which would instantly make me far less curious what the stock cam specs are.

Edit: just realized that what you're talking about is probably measuring something else in the valvetrain with teh cam in.

That actually might be an idea, but the intake and valve covers aren't coming off for at least another month

**johnunit** · 01-26-2011, 10:24 AM

Dug up the info in a book 4door was awesome enough to give to me.

The CS764 (or more accurately, a cam with identical lobe lift numbers) is the only cam listed for 1985 5.8L engines.

The 5.0L lopo cam was the CS759. I don't know if these changed with the switch to SEFI in 1986 or when they started being in Crown Victorias, but Ford literature only lists one cam for each engine for 1985.

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