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Wild Indian - Technical Article - Popular Hot Rodding Magazine
Kaase's engine may have been a Pontiac, but as far as the components, it was definitely a no-holds-barred build-up. Built on the new AllPontiac.com iron block casting, the structure was there to support the most serious of efforts. Kaase commented, "I knew they had these blocks [manufactured by Indian Adventures and sold by AllPontiac.com], and they are built by Roush, so that says it all. The things are awesome, four-bolt caps, Siamese bore. The machine work is impeccable. The cast-iron quality is really nice." The aftermarket block offers the flexibility to be creative with the combination, and we inquired as to Kaase's theories on how to fill it out with the basic combination. Kaase continued, "Being that it is a wedge that doesn't have canted valves, I didn't really think you could run the bore size much smaller than 4.310 inches. I might have chosen 4.250 inches or so if it was a Rat motor or something, because of the side-cant, but as you know, having the valves against the bores is terrible. If you have the intake valve up against the bore it is a bad thing. The best overall average good combination I thought for this motor was 4.310 by 4.350 inches. That would give 507 cubic inches, and it would give the heads just enough room to breathe. I just looked at it and decided that I wanted 200-plus thousandths between the intake valve and the bore and did what it took to get there." Achieving the required stroke employed a custom Sonny Bryant crank, with 2.000-inch rod journals, and 2.500-inch mains. The reduced journal diameters were primarily to reduce the oil requirements, necessitating main bearing spacers made by Kaase to allow the undersized main bearings to be used with the Pontiac block. The main bearings are 340 Chrysler units, and naturally the Bryant crank was custom built with these bearings in mind, with the appropriate journals and thrust surfaces. Kaase commented on the crank, "It's bordering on being too small of a main for that large a stroke, but since it is not going to go over 6,500 rpm it probably wouldn't flex too bad, and it has eight counterweights. It is a really nice crankshaft, and once I got it from Bryant, I just washed it and put it in. I had to have the people at All Pontiac find me an old junk crank and ship it to Bryant, and then Bryant had to make blueprints from it, because he's never made a crank for a Pontiac. Since this motor, he has made five or six of them, so I guess he's in the Pontiac crank business now. The [factory] cranks on those are sort of a problem, apparently." The connecting rods are custom Carillo units, a manufacturer Kaase felt provides the kind of quality he was after for an engine that was destined for over 200 dyno pulls in testing. The rods measured 6.500 inch. Kaase favors shorter rods for this application. "I like the short rod for a motor like this, but if it was any shorter than that, it mechanically would have worked, but the wrist-pin part of the piston would have been out of the bore at the bottom, and you don't want that. The bores are sort of short on these blocks. I think cylinder wall length is about six inches or so, and you don't want the wrist pin centerline coming out of the bottom into the crankcase with nothing to support it, so the 6.500-inch was a good all-around spec for it to work." For the lubrication system, Kaase used a Stef's pan, aided by a custom-built scraper. Kaase was impressed by the Stef's pan, relating that it worked really well as delivered. He added the scraper, and really wasn't sure if it contributed any further gain, making a point to say that the pan by itself seemed to work just as well. A stock Melling pump moves the oil, though Jon found the small bearings caused too much oil pressure. To relieve the problem, the pump was modified by trimming the bypass spring. This reduced the pressure. Of course the overall success of the engine is reliant on an effective set of cylinder heads, and again AllPontiac.com provided the castings. The heads were fitted with valves measuring 2.230 inch on the intake side, and 1.710 inch, exhaust. As Jon put it, "The bigger you get, the worse it closes it off [due to bore shrouding], but that is a good size for that size of a bore." The fully ported heads certainly flow well, peaking at 420 cfm on the intake side, no doubt aided by the substantial intake port size. The intake port cross-sectional area measures 3.4 square inches at the smallest point, adjacent to the pushrod area, while the short turn is just a little bigger, as is the rest of the runner. The intake port throat area, just under the valve seat, measures 90 percent to 91 percent of the valve diameter. On the exhaust side, peak flow measures approximately 275 cfm. Kaase kept the chamber volume very small at 37cc, which works in conjunction with a large mirror-image dish in the custom CP pistons to set the compression ratio to 12.4:1. The pistons are set in the bores to provide a piston-to-head clearance of 0.035 inch, for good squish and quench. The combustion chamber configuration features substantial quench pads on both sides of the chamber, an important consideration for efficient mixture motion and detonation tolerance. In the intake port of the head, Kaase used a rubber-like heat insulating material as a thermal barrier coating. The cam is a custom COMP solid roller, which required a custom billet core to be made, since the engine uses 55mm roller bearing journals. In development, Kaase ran two different grinds, and ended up with the bigger of the two, spec'ing out at 261/268-degrees duration at 0.050-inch tappet rise, ground on a 107-degree lobe separation. The cam is a 4-7 swap piece that alters the factory firing order. It was installed at 104 degrees, which was found to provide the best average in power in testing. With 1.8:1 ratio Crane rockers, the cam provides a very aggressive 0.886-inch lift, which required considerable attention to provide for valvetrain control. Kaase told PHR: "I used Manley springs. I ended up changing springs and putting stronger springs on it because I thought it might be getting out of control. Originally, I ran an oval track spring on it, a 1.55-inch dual spring. The intake valve in this thing is 6.600 inches long, and they weigh a lot, like 160 grams or so, and the power falls off at 6,200, so I'm figuring maybe the thing is going out of control. I put stronger springs on it, 300 on the seat and 800 pounds open, and it really didn't make much difference, but I just left them on to be safe--it didn't hurt the power." Comprising the rest of the valvetrain, heavy-duty Trend 3/8-inch, 0.135-wall pushrods were used. Elaborating on the valvetrain, Kaase disclosed, "I didn't use an offset rocker with an offset pushrod seat. I used a centered rocker, and I tilted it out a little bit. I have a lot of angle on it--I moved the rocker studs out. It would have been way easier with shaft rockers." Between the cylinder heads of Kaase's Pontiac is an Edelbrock Victor intake manifold. The manifold cross section is fairly consistent, although it gets taller and narrower as it goes up. Initially, the intake manifold runners had received the same thermal barrier coating used in the cylinder heads' intake runners, but it was removed when a power loss resulted. Kaase explained: "It hurt the power and I had to grind it all back out, but I think it was because the manifold was too small. I think it hurt the power because the manifold was bordering on being too small, and you're closing all the walls up about 20 thousandths. I had to grind it all back out and I gained 10 horsepower. The engine has a changed firing order. It's a 1-8-7-3, or a 4-7 swap. Because of this firing order it seems like it caused some problems in the manifold, and it made the number eight cylinder lean all the time, but with a different order it would have been somewhere else. We went to that firing order on our bigger [race] engines, and our crank life improved, so I think it is better on a bigger engine, but on a single four-barrel, I'm not sure." Topping the intake is a custom-modified King Demon RS carb. Relating to the carburetor, fitted with 1,100-cfm venturis, Jon told us, "I learned a few lessons last year on the carburetor; I had it where it didn't keep up with the good weather when I got here, and burned a spark plug out of it [the motor]. I got to the better conditions, and it didn't add more fuel; I had way too big a high-speed air bleed. I had a booster with a big flange and it made it want a huge high-speed [air bleed], like a 46 thousandths, and it made good power up top, but once I got here it wasn't the right set-up. I went the other way this year, with a 25 [thousandths] high-speed, with a regular booster in it. The jetting is all over the place, to even-out the distribution." A unique spacer with an anti-reversion sheer plate is mounted beneath the carb. According to Kaase, "It was worth 10 horsepower over anything I tried." The returning two-time Engine Masters champion surprised many of his fellow competitors by showing up to the '05 event with a Pontiac-based entry. While a repeat for a third victory was not to be, the showing proved what Pontiac fans have known for decades: these engines can make power with the best of them.  The spacer may appear simple...  The spacer may appear simple on the exterior, but a look inside reveals an extensively modified set-up utilizing a sheer plate to reduce reversion pulses, and a high level of porting execution. |  The shape of the spacer matches...  The shape of the spacer matches that of the reworked plenum of the Edelbrock Victor intake, which funnels the mixture to the extensively ported runners. Kaase notes that the cross sectional area in the runners remains relatively constant, despite the change in shape along their lengths. The waffle pattern at the bottom of the plenum is stock. |  Mating the intake manifold...  Mating the intake manifold to the heads required a set of thick spacers at the flange to meet the raised ports of the All Pontiac cylinder head castings. The water hose at the center of the spacer evacuates the highest point of the heads' water jackets. |  The two hoses from the center...  The two hoses from the center of the heads, in addition to two more from the rear of the cylinder heads, are plumbed to the coolant crossover below the thermostat housing to aid in controlling temperature. |  With a serious 0.886-inch...  With a serious 0.886-inch lift, the valvetrain can't be compromised. The Crane rockers are aided by a stiff stud girdle, which adds rigidity by linking the row of studs. Thick 0.135-inch wall, 3/8-inch pushrods transfer the cam's motion. |  A detailed look at the stud...  A detailed look at the stud arrangement shows the relocated intake studs, required to provide clearance for the wide intake ports. This cocks the intake rocker over at an angle, requiring the heavy-duty alignment yoke/guideplate to keep the intake rocker centered on the valve-tip. The arrangement Kaase used is the next best thing to a prohibited shaft-mounted rocker arrangement. |  With the valvetrain pulled...  With the valvetrain pulled from the heads, the length of the valves is striking. The long valves provide the design flexibility for a nice port shape, but the heavy valves required considerable spring load to control, especially in light of the extreme cam specs. |  A close look at the combustion...  A close look at the combustion chamber shows a very tight 37cc after serious welding. Custom tricks include the spark plug location, which is heavily biased to the exhaust side, and the use of a thermal barrier coating in the intake port. |  Inspecting the lifter valley...  Inspecting the lifter valley area of the AllPontiac.com block shows the extensively reinforced bulkheads; the structure of the block is vastly beefed in contrast to a production block. No special work is required in regard to drain-back. |  With only four head bolts...  With only four head bolts clamping each cylinder, Kaase's Pontiac makes good use of the clamping provided by the ARP studs. Note the twelve vertical gas ports in the CP pistons, which aid sealing the thin 0.043-inch rings under pressure. |  Kaase had good things to say...  Kaase had good things to say about the Stef's oil pan, with its built-in windage tray, and ran it without further modifications. |  Under the pan, Kaase fabricated...  Under the pan, Kaase fabricated this nicely executed aluminum scraper, though he commented that he was uncertain of its contribution to the engine's final output. The Bryant billet crank was used with no additional modification. |  Rather than go any shorter,...  Rather than go any shorter, Carillo rods in a 6.500-inch length were selected to keep the pistons from exiting the bottom of the sleeved bores excessively. |  Compare the shape of the piston's...  Compare the shape of the piston's dish to the combustion chamber, and you'll realize that half of the chamber is in the piston. Notice the low top ring placement, a configuration that is more tolerant of detonation. Friction coatings are evident on both the piston skirts and the bearings. |  We were told that one of the...  We were told that one of the trickiest operations in building this engine was fabricating the bearing spacers to reduce the Pontiac's main journals to the 2.500-inch small-block Mopar specification. |
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