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Discussion Starter #1
I finally got around to using my gap gauge to determine the recess on my Windsor pistons. They're .018 (.457mm), with minor valve reliefs on top left and lower right of the oval recess. With my 70 heads (60.4cc), what else would be needed to assess the compression? No idea why the opposite side valve reliefs. The deck height is for a 79 block, which I read was higher than earlier blocks - don't have that number.

The cam is an Edelbrock performer plus, with specs 201/214 duration at .050" lift, with lift 448/472.

Just trying to figure out if I should keep the short block as is, or replace the pistons and cam/lifters/springs. I'm going to keep the heads, and spend my 3-400 on roller rockers/studs/guide plates, machining a bit for the studs, and maybe pistons.

Read at Edelbrock's site the following: CAUTION: Use Edelbrock Performer-Plus Timing Chain and Gear Set #7811 or #7820. Do not use late model timing chain and gear sets that are designed for emission-controlled engines. These timing sets are machined in a retarded position and are not recommended for this camshaft installation. Edelbrock Timing Sets feature three keyways for specified timing selection.

Guess I better figure out if that's an issue as well. I'll be taking off the balancer and timing chain cover today to figure out if the cam is properly degreed. Fun, fun, fun. Eric.
 

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Contributing Sr Motorhead
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Deck height for later blocks is 9.503, early block are 9.480.

Pistons are stock '79? or whose are they? Pistons likely have a notch or arrow that denotes front of engine... If all are facing front, then valve reliefs would be opposite each other for the other cylinder bank... Bigger intake valves, so that notch is bigger... Looking at my SBF book, the early 60.4 heads will raise the C.R. of an otherwise stock 79 351W to 8.7:1 (79 was 8.2:1 stock)
 

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Discussion Starter #3
Thanks for the feedback, Milo. Yeah, anemic 8.7 compression ratio. I need to bump that up a full point. I'm thinking of picking up these pistons, rockers and pushrods. Will these set me up for 9.5-10 compression? Studs will be coming this week off eBay (3/8"), along with guide plates from a member here. I'll be porting/polishing the heads by next weekend.

http://cgi.ebay.com/ebaymotors/JE-P...r_Truck_Parts_Accessories&hash=item4cf57e902a
http://cgi.ebay.com/ebaymotors/CHRO...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
http://cgi.ebay.com/ebaymotors/SBF-...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
 

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If I recall, the early (70-71) pistons had a rather large dish. Flat top pistons and those small chamber heads may be too high for pump gas.
CHECK OUT PAGE 38
 

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You do realize that those pistons are priced EACH, don't you? (read the fine print) That is $975 for the set!!!
 

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Discussion Starter #6
Milo, thanks for saving me the embarrassment. I've been known to have expensive tastes, but never that much for freaking pistons. Guess I'll be searching for others. I went ahead and picked up the pushrods and rockers listed as links in my prior reply. I did see some good pistons for $159.
 

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Discussion Starter #7
I don't know anything about the quality, or lack thereof, of the parts used for this rebuild 21 years ago. Is the timing chain a good one? What's the analysis of a worn chain? Put a straight edge against one side of the crank/cam, pull the chain for gap, then use a gap gauge?

Rockers and pushrods I've paid for, and need to put some more money on my slush fund/paypal credit card to pay for the pistons/rings. Con rod bearings are next. Can I replace the pistons myself, or does it take a mechanic to do?
 

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Appears to be a very good set from Comp Cams. As long as the chain is not sloppy and the cam end play is within specs (.003-.006" IIRC) I'd use it.
You'll need to have a machine shop put the pistons on the connecting rods unless you have the equipment. The wrist pins are an interference fit into the rods. Rods are heated to around 800F so the wrist pins can be slipped in. Pistons go on rods in different directions depending on the cylinder.
 

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Discussion Starter #9
The pushrods I ordered for the W are 8.150" in length. The 79 block has deck height of 9.502, vs. 9.480" for the 70. Tried to find info on pushrod lengths here, but found nothing. Did Ford keep the pushrods the same length after increasing the deck height, to reduce emissions without messing with the block/crank/piston design? I'm thinking of having the NAPA machine shop guy shave some off the heads to bump up a little more on compression, along with shaving the stud posts for roller rockers/guides. I'll also be taking the piston/con rods out tonight, so the NAPA guy can replace the pistons. Anyone interested in the pistons/rings for $25? The car saw maybe two thousand miles max on the rebuild in '90. Can send pics. Eric
 

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My book calls for 8.145" from 1969-1986 which would probably work as long as the (1) valves are stock length (2) stock height lifters (3) deck or heads haven't been shaved (4) using factory heads.
Instead of shaving the heads, consider "zero" decking the block. This puts the pistons at the top of the deck and helps the quench area of the combustion chamber. Usually the pistons sit down in the bore .016-.018" in the bore. Just keep the compression ratio in the 10/1 range unless you want to mix race gas.
 

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Discussion Starter #11
Thanks for the info, Art. I'll scratch off my list the part about shaving the heads. With the 1.7 ratio rollers, I should be sitting pretty nice. Not sure if acccurate, but the eBay store guy who sold them to me said that a cam with .500 lift would bump up to an equivalent .530 with those rollers. Anyone else switched to the higher ratio rollers?

By the way, is there any way to test the used Edelbrock springs and lifters while I have her all stripped down? There are so few miles on them... Would slightly stronger springs be acceptable for the current cam/lifters, plus new 1.7 rollers setup (2182 cam)?

Finally, I'll be taking the pistons/con rods out tonight, eagerly awaiting the new flat/relief pistons and rings. Do I need to use a micrometer(?) to gauge if any shaving done on the crank/con rod connections, thereby dictating I need thicker con rod bearings? Bearings wouldn't have any specs on them, right? Guess I'll know for sure tonight.
 

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Rod and main bearings are marked std., .001, .002, .010", .020, etc.

An automotive machinist should check the crank to determine if it should be ground or if a polish will suffice.

The cam card will give a recommended seat pressure for the installed height for the springs, again, the machine shop should be able to determine if the springs will work.

Multiply the lobe lift x 1.6 or 1.7 to determine valve lift.

Stick a piece of 5/16" fuel hose over the rod bolts when you knock the pistons out, the rod bolts will ruin the crank journals if they touch.

You didn't ask but you'll be money (and power) ahead if you use aftermarket heads over the W factory heads. Aftermarket heads already have the studs, guideplates and larger valves. Much better flow numbers too. http://www.summitracing.com/parts/EDL-60259/
 

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Discussion Starter #13
But what about the headers? Those aftermarket heads probably require another $200+ outlay for headers. I'm already at $500 spent on rockers, pistons, rockers, studs, pushrods, rings, excluding machine work for the pistons and stud mount shavings.

I have perfect hooker headers for my current heads. Something in the back of my cranium is telling me that I might have a winning invention creating some sort of fan setup at the end of the tailpipes to pull/vacuum the exhaust, instead of just relying on the piston to push it out.
 

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SBF headers are SBF headers... Unless you start getting into the more exotic oversize-port CNC-ported offerings.

As for Art's suggestion of decking the block - ehhhh... Unless you're sure what pistons are in there now, I wouldn't. The factory piston-to-deckheight clearance varies by year - .035 for the 69-72 9.480 block, then .028 for 73-76 in the 9.503"-tall block, and .0145 for the 77-newer also in the 9.503" block. That's because they were changing the piston-wristpin to top of piston height, from 1.739, 1.769 and 1.782" respectively. That last set of numbers shows over a .040" difference in pin height between year of manufacture!

When ordering replacement pistons, you have to pay attention to that pin height! For example, if you ordered early pistons and put them in a late-model block, you're gonna have an extremely low compression ratio. Conversely, if you tried to put '79-spec pistons in an early block, they'd stick up too far -- being .008 above the top of the block! You won't find that critical pin height info on eBay! You have to go to the piston manufacturer's website or print catalog and see for yourself. They will also give you the piston /valve relief volume figure you need to accurately calclulate your CR.
 

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I wouldn't cut anything until I determined what the compression ratio is first. Too much compression and you'll have to run the timing retarded to keep the preignition down.
I would much rather have a smooth running 9/1 compression ratio that could use 36-40* timing than a 11/1 motor that rattled itself to death.

I believe Milo will agree.... :D

And ordering parts over eBay is a crap-shoot at best.
 

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Discussion Starter #16 (Edited)
My headers are fit for the exhaust ports on the 70 heads - vertical rectangle. Seems lots of aftermarket heads have plenty larger ports are appear to be square.

Lots of extra great spec info Milo. Thanks. The Speed Pro hypereutectic (sp from the guy's auction?) flat-top pistons have a compression height of 1.772". I couldn't find any piston specs on the federalmogul.com website.
Will check others that sell them, like jegs.

The connecting rods are C9OE, but maybe they're all the same?

As for the old pistons/rings - 7 of the eight are beautiful. The 8th met with an accident while trying to remove the crank bolt. I have the "wing that broke off - was a straight break on #7 piston. Repairable? Anyone wants them after I have the mechanic replace them, let me know. Just pay for shipping (~ $10-15 max?). I'll have the box from the new pistons.


Art, I finally checked out p.36 from your earlier reply. For 60cc and +15cc dish piston, would be 9.8 compression. The Speed Pro pistons I'm to receive are +12cc. May be on the high side for today's gas, but think I'm on the right track. I think the con rod bearing caps indeed are .0100, so just need to pick up more of the same. Don't have a trained eye, but that crank is absolutely beautiful.
 

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Discussion Starter #17
I noticed on the top con rod bearings that the oil hole was missing - was just an impression on the backside of the bearing where the oil from the con rod was supposed to flow thru the bearing to the crank. Saw the clevite bearings on eBay that DID have the bearing hole. Did the mechanic who put the W together for me hose up this piece?

http://cgi.ebay.com/ebaymotors/Clev...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories
 

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Discussion Starter #19
Yep. All the rods had the same holes and top cap indicating there should have been holes in the caps. Is that a rarity con rod-wise?
 

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The holes were in the upper part of the rods. A hole was there to squirt oil on the cylinder wall.
I've seen 351w rods cast with the squirter but not drilled. The only rod I've seen drilled was an old set of 260 rods.

Squirter isn't needed.
 
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