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Budget Mod Motor Build - The Mod Motor Rocks

Shed Those Pushrods And Embrace The Future. The Cobra Guys Have Known All Along That The Mod Motor Rocks

By , Photography by Nick McKinney, Courtesy Ford Racing and Performance Parts,

Performance 2V Build No. 1
We talked with Modular Head Shop's Nick McKinney at length about his recommendations for a performance build. He told us nearly 60 percent of his customers are early Mustang, Crown Vic, Thunderbird, and Cougar owners. Since these are predominately two-valve cars, he's something of a 2V specialist and has several combinations he recommends to suit his customers' budgets. On his website, McKinney lists a parts combination that will make at least 300 hp at the wheels. Best of all, it costs less than $2,500, including new gaskets, timing chain tensioners, and sprockets. It's basically a cam, head, and intake swap, so you can reuse your bottom end. Assuming everything is in good shape, the stock reciprocating assembly will easily handle the increased power. We'll highlight some of the parts here.

You will bend your intake valves for sure if you run an aggressive camshaft. McKinney told us proper cam timing is critical. He recommended maintaining a 0.035-inch piston-to-valve clearance, and it is easy to exceed this spec. For example, installing a popular street cam with 225 degrees duration at a 112-degree intake centerline will give you 0.070 inch of clearance. Advancing that same cam 2 degrees to 110 will give you 0.035 inch of clearance. Advance it 2 more degrees to 108, and you will only have 0.005 inch of clearance. The problem is that these engines like more intake valve timing, and a popular option is to have the pistons notched for intake valve clearance. You can send McKinney your pistons and he'll notch them for $129. It's also a good idea to replace the intake valves with aftermarket ones without the perimeter ring. McKinney also stressed that the cam timing should always be checked. He said the factory timing sprockets are notoriously inaccurate and can be off by as much as 4 degrees either advanced or retarded. Degree your cams when assembling the engine. If the timing is off, you'll need to buy a set of zeroed or adjustable gears. Rounding out the 300hp combo, you can reuse your factory PI intake and add both a JLT intake with a 90mm mass airflow sensor and a performance exhaust system with a pair of long-tube headers: simple, cheap, and effective. If you still have some extra money to spend, McKinney recommends building all this on top of an aluminum 4V block out of a Mark VIII. In stock configuration, these were 10.0:1 engines. With PI heads, your compression ratio will be almost 12.0:1. That plus the nearly 80-pound weight advantage of the aluminum block will give you even better performance at the track. Whether you use the aluminum block or not, with this combination you'll be making more power at the wheels than the Camaro and Mustang guys are making at the crank.

Power Improved By The Numbers
Engine Piston Dish Combustion Chamber Size Compression Ratio
NPI 11 cc 51 cc 9.30:1
PI 17 cc 42cc 9.74:1
Ideal* 11 cc 42 cc 10.4:1
*Using a stock head gasket with 0.036-inch compressed thickness with -0.015-inch piston-to-deck height

Cam Specs
NPI 201/208 duration at 0.050, 0.462/0.462 lift, 114/113 intake/exhaust centerline
PI 200/209 duration at 0.050, 0.505/0.531 lift, 116/116 intake/exhaust centerline

Valve size 1.752/1.339-inch
Cam follower Roller type with 1.80:1 ratio

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