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Old 11-01-2012, 11:05 PM
spookypt spookypt is offline
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Default 351w

Hi Mike, you've got me thinking I might start a thread on my particular car if there is interest as some may find it interesting being from the USA/Sth Africa. But seeing as though where in the topic of engines....

I generally tell people its a smokey ole 351w windsor but between you and me..

Here's some light reading...

The engine is a 351w (372 cube) Dart Iron Eagle 9.2 deck 302 mains.
Sonny Bryant Steel Crank 3.450 Stroke Nascar Crankshaft
Eagle Steel H Beam Rods
Comp Cams Custom Crankshaft Grind 318DR-12
Edelbrock 2929 9.2 Super Victor Intake Manifold
4 stage Dry sump
960cfm proform Carb
Dual MSD
13.5:1 Compression running 112-116 Leaded Sunoco Supreme Race fuel
The bits list goes on and on...
The engine will turn to 9200rpm with that combo but is currently rev limited to 8000rpm to increase durability where possible.

The engine was built and refreshed in the USA prior to being sent to me... After a full USA engine rebuild/refresh..... I did a oil filter inspection after its
1st outing and found it was eating Valve Stem Seals...

So my new car/engine is off to my engine builder for an open chested inspection.

(If you've just bought an engine from the States don't read any further)

On removal of tappet covers we discovered the roller rockers had all been rubbing on their retainers, some attempt had been made to clearance rocker to retainer but it was insufficient. The valve stem seal problem was attributed to the fact that the valve stem seal area of the valve guide had been machined down to .480”, our guess is, to fit a smaller o.d. seal to clear the triple valve springs. The problem with doing this was - the grooves on the valve guides that grip the seals was machined off allowing the seals to
slide off very easily. Using the correct small o.d. seals on the original .530” o.d. valve guide would have saved this whole problem, and in fact given more seal to spring clearance than the seals that were used.



Another issue we found with the cylinder heads was the helicoils to hold the rocker stands. These were very loose in the heads and some had no parent thread left or very little. To correct this we drilled and tapped the
heads to 3/4 unc, screwed in some 4340 slugs and drilled and tapped to 7/16 unc. We reckon the side load caused by rockers to retainers caused this problem.

Now on further inspection we found the bottom end also had problems - firstly bottoms of the bores were not chamfered causing piston skirts to scrape, so we chamfered bores and coated pistons.

Secondly, the middle cam bearing was in very bad condition, which was easily explained by the fact
oil restrictors were fitted to restrict oil flow to cam bearings , all fine except the plug in the middle gallery had "no hole in it", thus the bearing was receiving no oil under pressure.

The block surface finish was far too coarse for the MLS Gaskets used and required refinishing. There was crankshaft damage to the webbing that had been dressed up so we feel it had obviously been in another engine that had failed. The marks in the journals would also suggest the crank had been
polished leaving valleys and no peaks and the crank needed grinding.

Lastly for a high performance engine there was no port matching in the manifold – even though it is not a fault as such, the manifold should have been match ported to heads particularly on a build like this, no point having CNC ports when the manifold only creates dead areas in ports.

So, I'd suggest the engine "insert appropriate name here" went out and bought the best parts he could find and the proceeded to WallMart for a 6 pack of Buds and a few blue tarps to set up in the backyard and build MY ENGINE.

On discussions with my US friends the above issues were not covered by warranty as IT'S A RACE ENGINE!!!!

On top of all that the metal bits lunched my dry sump pump as no inlign filters were used. Order up!!!!!

That all being said I did get some fiscal recourse through the cars manufacturer which was better than a kick in the mellon.

Its a stout engine but it will never be stretched enough by me to appreciate its full potential.

Spookypt
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