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-   -   455 Super Duty build (https://forums.maxperformanceinc.com/forums/showthread.php?t=787703)

Cliff R 03-11-2016 09:14 AM

455 Super Duty build
 
4 Attachment(s)
We are just completing a 1974 455 Super Duty engine build. The ill fated engine only had a few hundred miles on it after a pretty "high end" build and it failed.

The short block is finished and we're going to button the rest up next week, then put it up on the dyno.

The build is as follows, .040" over, custom Ross flat top pistons (exactly zero deck), Felpro .039" head gaskets, Eagle rods, balanced assembly, stock heads that have been previously ported but we don't know by who or the head flow. Doesn't look overly dramatic, mostly opened up at the intake gaskets from what I can see, followed by some work back into the runners.

We installed a custom ground 230/236/112 HR camshaft, and will use 1.65 Harland Sharp rocker arms. It will have a stock intake (not ported in any way, just gasket matched, stock 1974 Super Duty Q-jet part number 7044273, and a stock 1974 Super Duty distributor (points).

Hoping for close to 1hp/cid and 530-540tq for peak numbers. We woln't be chasing the tune really hard for best numbers, just going to run it in on the dyno, check for leaks, and make a few pulls on it. I'll put the dyno sheets up after we're done......Cliff

steve25 03-11-2016 09:17 AM

Good / lucky thing that however it failed the heads and block where still good !

Half-Inch Stud 03-11-2016 09:21 AM

Curious to know the failure mode ( for purely technical reasons) .

Curious to know the compression & cam ( for purely MPG reasons ) because my most excellent combo has a gas guzzling problem! Only runs well with the 2-circuit 1050, and unable to idle with my Q-JETs.

Nicks67GTO 03-11-2016 09:29 AM

Nice!

Aren't super duty blocks set up for dry sump oiling capability from the factory? Do you have any pics of the factory dry sump mods on the block while it's apart?

Cliff R 03-11-2016 09:37 AM

The engine build was "high end" and overall not all that badly done. They made a couple of small mistakes that doomed it from the beginning.

The used lash caps on the valves, one was "soft" and got ground up to nothing putting metal thru the entire assembly. Two more were missing from the tops of the valves and loose in the assembly, not sure how that happened there?

The big showstopper were the "old school" forged/domed pistons, which require quite a bit of clearance as they are older alloys. They were too tight and two grabbed the cylinder walls destroying the pistons and tearing the bores up pretty hard.

I didn't cc the heads but it should be around 8.8 or so compression, it could go a little higher than that as they were previously milled and we had to cut them again to clean them up.

The cam is a custom ground HR, 281/287, 230/236 @ .050 on a 112LSA. Lift with the rockers we're running will be close to .580/590"......Cliff

blykins 03-11-2016 10:02 AM

Normally, when you lose lash caps, it's because there has been a total loss of valvetrain control, or a valve hung in the guide.

Pistons are usually made to fit the bores and have the clearance built in. So if the recommended clearance was .005", the pistons should have been .005" smaller than the bore size they were intended to fit. Wonder what happened? Maybe ring gap too tight?

johnta1 03-11-2016 11:14 AM

Sounds like a cool build!

I would think the HP from the SD heads should be easily attained.

In one pic you show studs for the mains but the caps are bolted down in the later pics?

With my SD I used a tight LSA solid roller cam (with lot more lift) and it made some really good HP.

:)

Half-Inch Stud 03-11-2016 11:17 AM

Quote:

Originally Posted by Cliff R (Post 5546257)
The engine build......should be around 8.8 or so compression.....cam is a custom ground HR, 281/287, 230/236 @ .050 on a 112LSA. Lift with the rockers we're running will be close to .580/590"......Cliff

Roger that 2-slug scuff....my Forged ROSS Slugs came with a super-tight Recommended cold clearance fit/check: Block Half-filled with the good cement & CYL walls still good after a couple re-assemblies. No Air filter & no blowby. But that will change soon.

Not far off from my Signature combo. Looks like my 0.050 DURATION is TOO HIGH:
I gots 4" HG at idle in gear, 6" HG in Neutral. Gots 16" in level highway Cruise, that goes to 20" when I let off the pedal. BUTT the mileage is atrocious across Idle thru high speed cruise. May not be the 3.54:1 gear alone. Therefore my 12.2 ET Signature combo is horrible for MPG.

Hope your SD-455 Combo achieves excellent MPG. Do you have an ET/MPH & Cruise MPG prediction?

Doug 03-11-2016 06:35 PM

Do a dyno run with a good tri-power setup for comparison.

Cliff R 03-11-2016 07:20 PM

"In one pic you show studs for the mains but the caps are bolted down in the later pics?"

It uses studs, that's what it showed up with and all with only a few hundred miles on it, so we re-used them. If it was being done here from scratch I would have used the original bolts for the main caps, provided they were in good shape.....Cliff

critter 03-12-2016 12:21 AM

It sounds very much like my car before I retired my SD heads and went to E-heads. Compression bump will help and looking at the pictures you're running those pistons about .020 out of the hole. I expect you'll see that right around 470 hp and enough torque to make you smile a lot. Just a guess. I'll be curious to see the numbers.

Cliff R 03-12-2016 08:18 AM

It's actually EXACTLY zero deck, funny how a camera can't catch that deal. The piston just barely touch a machinist ruler when they reach TDC.

We'd like to see around 1hp/cid with this engine build, I think it will be right there......Cliff

Larry Navarro 03-12-2016 10:32 AM

my first SD engine build was done with the STOCK single trough pistons. I can't remember what the deck height was but I opted to use the STOCK NOS head gaskets which measured at .060 thickness.
Wanted to keep the CR close to the factory number of 8.4:1
Basically because I was installing the HO Racing HC-63 camshaft.

promptcritical 03-12-2016 10:56 AM

Quote:

Originally Posted by Cliff R (Post 5546257)
The engine build was "high end" and overall not all that badly done. They made a couple of small mistakes that doomed it from the beginning.

The used lash caps on the valves, one was "soft" and got ground up to nothing putting metal thru the entire assembly. Two more were missing from the tops of the valves and loose in the assembly, not sure how that happened there?

The big showstopper were the "old school" forged/domed pistons, which require quite a bit of clearance as they are older alloys. They were too tight and two grabbed the cylinder walls destroying the pistons and tearing the bores up pretty hard.

I didn't cc the heads but it should be around 8.8 or so compression, it could go a little higher than that as they were previously milled and we had to cut them again to clean them up.

The cam is a custom ground HR, 281/287, 230/236 @ .050 on a 112LSA. Lift with the rockers we're running will be close to .580/590"......Cliff

So Cliff. Was the piston problem the clearance they used or the dome? I have small domed Pistons on my 7F6 head 455 HO and it seems to be okay. No detonation that I can hear at least. Been running for years that way. I've always had some concerns with the domes.

Cliff R 03-12-2016 12:01 PM

It appeared to be clearance as the sides on two of the pistons are ripped up pretty good. Probably didn't help that it was running a bit warmer than it should have.

Like a said earlier, this was a pretty "high end" build, Milodon gear drive, solid roller, polished the side beams on the SD forged rods, balanced, stud girdle, domed pistons, some head porting, etc. The owner did tell me that although it made good power, it refused to idle well, and they were making efforts to tune the engine for better street manners when it developed issues and had to be pulled out.......Cliff

77 TRASHCAN 03-12-2016 07:29 PM

There's many different types of machines that you can bore an engine block with. Some are not as precise as others.
If you are boring a hole that is not completely round, everything else in the following machine work process is screwed also.

Maybe some of you that do this work on a daily basis can chime in on what you use.

The old timey method of using a boring bar (a machine that is clamped onto the block through an adjacent bore) is thought out dated by many. My machinist buddy doesn't like the looks of some of these newer fancy machines (knowing there are different types).

The clearances that piston manufacturers recommend are bore/hone jobs without the use of a torque plate, for their own liability reasons. I've seen 2 SBC's with 5 shiny spots in the bores, right by the head bolt holes...imagine that. Every brand of engine is different though.

I've read about Cliff and others tightening up the bore clearance on some engines. This cannot be done without a proper hone procedure using a torque plate! Other things have helped in this area, include better light weight pistons, better machine techniques (including the folks using the machines, above all!) better hones and better torque plates.

I've seen my engine builder in his shop measuring the bore of a block with a dial bore gauge, many times...back then I wondered why...

mgarblik 03-12-2016 08:43 PM

We use a Rottler F5A boring mill. It is basically a semi-automated version of the old boring mill design they have used since the early 1970's. Rottler produces much more expensive CNC boring mills and multi-function machines. Our mill is fairly accurate but has it's limitations. The new bore is located off the original bore, so offset boring with this machine is very difficult. It can bore to +-.0003" out of round and about .0005" top to bottom. I leave a minimum .007" to do a 3 or 4 stage plateau hone on most blocks. Cast pistons and even some hyperutectic pistons run pretty tight. I build some street engines at .002-.0025. If they are round and straight with the right surface finish, no issues and very quiet. By contrast, the funny car we run at .013-.014". It depends on what you are doing with the engine and what the piston manufacturer wants.

hurryinhoosier62 03-13-2016 12:02 AM

Quote:

Originally Posted by 77 TRASHCAN (Post 5546868)
There's many different types of machines that you can bore an engine block with. Some are not as precise as others.
If you are boring a hole that is not completely round, everything else in the following machine work process is screwed also.

Maybe some of you that do this work on a daily basis can chime in on what you use.

The old timey method of using a boring bar (a machine that is clamped onto the block through an adjacent bore) is thought out dated by many. My machinist buddy doesn't like the looks of some of these newer fancy machines (knowing there are different types).

The clearances that piston manufacturers recommend are bore/hone jobs without the use of a torque plate, for their own liability reasons. I've seen 2 SBC's with 5 shiny spots in the bores, right by the head bolt holes...imagine that. Every brand of engine is different though.

I've read about Cliff and others tightening up the bore clearance on some engines. This cannot be done without a proper hone procedure using a torque plate! Other things have helped in this area, include better light weight pistons, better machine techniques (including the folks using the machines, above all!) better hones and better torque plates.

I've seen my engine builder in his shop measuring the bore of a block with a dial bore gauge, many times...back then I wondered why...

The quality of work ISN'T determined by the equipment used; it's determined by the skill of the machinist. The old guy I used for years before I became a machinist had an ancient Kwik-Way bolt-on boring bar. I've seen him bore a cylinder nearly as accurately as an F90 Rottler. Additionally, I've seen guys reduce good blocks into boat anchors with F90 Rottlers because they didn't have the skill or experience to alter the bore's center line. Most aftermarket piston manufacturer recommend torque plating bocks for honing, whether they're gasoline or diesel engines.

Half-Inch Stud 03-13-2016 09:09 AM

The machinist in Eastern PA was able to jerk my bores to align concentrically with the top-bottom sonobore readings. Really tight slug-bore clearance ( memory 0.0045") No air filter & no blow by. Time to install an air filter assembly huh.

Will be interesting to hear that the SD-455 build here break-in & run results. My interest is the idle personality.

sdbob 03-14-2016 10:46 AM

I'm watching Cliff as I have a SD that needs rebuilt also.Just stk rebuild with a higher lift Sd cam.


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