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Discussion Starter #1
I am going to be doing a full rebuild of a 351W 4V from a 1969 cougar. It has been sitting since 1992, so there are going to be all kinds of fun little surprises to be found inside, I'm sure.

Here is the parts list:
Scat 357 rotating assembly. Cast crank, forged 4340 rods, forged pistons
Comp Cams 275DEH cam
Comp Cams Double roller timing set
Comp Cams Hydraulic flat tappet lifters
Trick Flow High Port 192 heads (assembled)
Trick Flow Full roller 1.6 rockers
Edelbrock Performer RPM intake
Tuff Stuff High flow water pump
Melling High volume oil pump
Trick Flow Engine Gasket set
Mallory Optical Distributor
MSD 6AL
Hedman Long tube headers

Machine Work:
Line bore crank and cam
True the cylinder head mating surface, reducing deck clearance down to a minimum of 0.015", ideally staying closer to 0.020"
Bore and Hone. 0.030" ideally


So, with that mess laid out, what are your thoughts?
 

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If I were you I'd go retrofit roller cam, just because of the low-to-non existence of ZDDP in our oils these days needed to make a flat tappet cam last. I did my roller conversion with the engine still in the car, but it is much easier if you can drill/tap the retaining bolt holes before the cam bearings are installed. I used a Comp Cams XR-276RF-HR cam and stock FoMoCo 5.0L roller lifters/retaining spider/dogbones. No worries about the cam/lifters surviving break-in. Just one break-in failure and you're already spending more than going roller in the first place!

If you don't want to go roller, I'd strongly recommend the Extreme Energy series - probably either the XE268 or XE274 - since they're a more modern grind with a high lift/short duration with very fast ramps that will give you the power you crave plus better manifold vacuum and crisper throttle response.

Not too keen on Mallory distributors, either. Just use a stock reman 351W Ford Duraspark dizzy (~$50 from parts store) to trigger your MSD unit.

Gotta watch the aftermarket waterpumps, too, since they may not have the bosses/boltholes for your accessory brackets - ask me how I know... :( ( I have a high-flow sitting on the shelf now since it didn't...)

Remember that 69-72 351Ws already have a short deck height of only 9.480" compared to the later blocks having a 9.503 deck.
 

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I absolutely agree. I went with a Comp 280H cam and an MSD pro billet w/o vac advance 14 years ago. Now that it is all together and running great, I can't justify tearing it apart and spending all the money for 20 hp. I wish I knew then what I know now....

Go for a roller cam. It doesn't need special oil, you can reuse the lifters if you change the cam, no break in worries and it makes more power. Any cam between 220 and 230 @0.50" will sound and run great.

For the street, a vacuum advance distributor is highly recommended. MSD pro billet distributors use exactly the same magnetic triggering mechanism as the Duraspark dizzys. It will work great with the MSD 6AL.
 

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...Machine Work:
Line bore crank and cam
Bore and Hone. 0.030" ideally...
Two comments.

First, no one line bores the cam holes. There may be obscure availability of oversize (OD) cam bearings, but this situation is almost never encountered. Your machine shop will pop in a new set of OEM dimension bearings and 99.9% of the time the cam fits perfectly. In the rare occasion it does not, they find the tight journal and use a piece of a piston ring to scrape the offending bearing babbit until the tightness is alleviated.

Second, why bore .030" if the block doesn't need it? Less is more, more strength left in the block. .020" is fine if the wear is small enough allow for it. Having said that, .030" is the most common oversize.

Okay, three comments. :buck:

Why would you put a completely new reciprocating assembly including aftermarket crank and rods and not go for "the full monty"?? As in 408? If you are staying 351 CI with just an overbore, keep the stock rods and crank for crying out loud!

Hope this helps.

Regards,

Bob
 

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Discussion Starter #6 (Edited)
Piece of mind more than anything. My procurement of the new rotating assembly is pending inspection of factory rods and crank. If they check out and are okay, I may reuse them. That would allow for more money to be shunted towards the roller retrofit.
 

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Your '69 block will not have the raised boss for the two 1/4-20 spider bolts, but you can do it anyway. The bolt holes you'll need to drill are right over the cam bearings. If you drill/tap before installing the bearings you're OK. Otherwise, be careful not to go too far.

On mine I fudged a bit and used 1/4-20 stud with JB Weld as thread glue (aka loc-tite), ran down a stop/jam nut, covered that with more JB weld over that. The spider really isn't under any great strain - it is there just to hold the dog bones down that keep the OEM roller lifters aligned.
 

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Are there any downsides to using a reduced base circle cam? Is it better to use a "full" base circle cam and retrofit lifters?
 

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Discussion Starter #11 (Edited)
I think I am gonna go with the cam you recommended. I just ordered the spiders, dogbone, and lifters. You guys have saved me about $800. THANKS!!

I am looking at the TFS pistons to match the heads, and I found the optimal combo has an air fuel ratio around 9.42:1. Will this run on 93 octane? Lower? My truck has 9.7:1 and runs on 87. Totally different engines, but still, stands to reason, that with bore and stroke so similar, that it would be able to run on pump gas. (My truck has a bore of 3.958, and a stroke of 3.31)


Do I drill all the way through to the cam journals or do I drill to a certain depth? I would imagine as long as thereis 1/2"~3/4" of thread for the bolt to grab on top, with a little bit of adhesive to help hold it in, it would be fine. But I would rather be right than replacing a block or welding on the valley pan.
 

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Are there any downsides to using a reduced base circle cam? Is it better to use a "full" base circle cam and retrofit lifters?
You cannot use the 'full' roller cam with OEM roller lifters in an early block! You CAN use a full base circle cam if you use special (expen$ive) aftermarket hydraulic or solid roller lifters.
 

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I think I am gonna go with the cam you recommended. I just ordered the spiders, dogbone, and lifters. You guys have saved me about $800. THANKS!!
Which cam???
 

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You only need to drill/tap less than 1/4" deep. The tapping is the tough part if the motor is assembled since it is difficult to tap all the way to the bottom of the hole. I was only able to get the stud to hold by about two threads so that's why I did the JB weld/jam nut/more JB weld... I took the intake off a couple thousand miles later (changed form Performer RPM to Torker). While I was in there I checked the epoxied-in stud and and it hadn't loosened or slipped.
 

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Discussion Starter #15
The XR276HR. I should be pulling the engine this weekend. It has sat under a tree for the last 20 years, so it will be interesting to see what kinds of critters have made my cylinders their home.
 

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Make sure you get the retrofit roller cam XR276RF-HR part number 35-424-8, and not the regular base circle cam! That cam also needs double valvesprings and the appropriate retainers, so make sure your heads can accommodate those! My 'spare' set of TFS Highports do, but I didn't buy the heads new so I'm not sure how they come from the factory

You'll need hardened pushrods, but you'll probably have to wait until the motor is almost completely assembled before you can accurately measure what length you'll need. The new pushrods will be required and will be a different length due to new cam/lifter/head specs.

You can also save a few bucks on the rocker arms if you went with another brand. Harland Sharp is a well-respected name brand that is about $50 cheaper than the Trick Flow rockers. Stay away from the Summit or Jegs house brand or the ProForm Chinese crap.
 

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Discussion Starter #17
How well do you like the High ports? Are there heads you would recommend over them around the same price range? I was considering a pair of AFR 185s, but had always heard that Trick Flow was one of the best. Any preference on ring material and facing? I was leaning towards ductile iron with a moly facing for the top ring, with an oil ring with around 16lb of tension.
 

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To be honest, I bought my high ports but never used them. With the raised exhaust ports (.75" over stock) I was concerned that I wouldn't be able to get my headers to fit. They're still on my shelf... I ended up finding a pair of professionally ported World Windsor Seniors that flow even better than the high ports so those are on my 393W (351W stroker) now.

Another forum member is using a set of Patriot Performance 185 heads on his 418W stroker build. At only $965/pr for assembled heads, that's a good budget head and they flow pretty good, too. I don't have any first-hand knowledge of these heads, but they're NOT the cheap ProForm junk that everybody sells...
 

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Discussion Starter #19 (Edited)
I like the look of the Patriots, so that may be a possibility. The flow numbers are great. My only question is the springs that they have. I dont want to wind up with coil bind using the retrofit cam.

I got to get the engine bay cleaned out and rip the engine out this weekend. After closer inspection, it has a points distributor, but no coil, no alternator,but it has power steering, power brakes, and AC. :)

Where would I find the identifiers for a Holley carb? My neighbor said it looked like a double pumper. I'm new to carburetors, so I haven't a clue other than it says Holley.
 

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Discussion Starter #20
Another question. Factory AF is ~10.75:1 on the 4v windsor. Is there any issue with staying close to this number? Didn't the factory engine setup run on 87~89 octane fuel? If so, can I still retain the higher compression and run on 92 without spark knock, theoretically?
 
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