Craig Dienes came to use with a bunch of Pontiac UN-Obtainium and he wanted to build a strong tribute engine for his 1968 Pontiac GTO.  We started off by dynoing what Craig had and that was a .030 over 400 with a set of cast iron #44  PMD Ram Air 5 heads WITH the matching PMD dual plane Ram Air 5 intake.  The 30+ year old built 400 engine had solid flat lifter and what appeared to be a roller cam…. that combo made 454 hp at 6300 rpm and 408.5 ft lbs of torque at 5700 rpm which was more than we thought it would make.  After getting our original as is / stock numbers we tuned on the engine for a bit and swapped out some parts….. Our best results from this Ram Air 5 headed 400 cid made 485.8 hp at 6400 rpm and 428.6 ft lbs of torque at 5300 rpm! Not too bad but not matter how hard we were going to try, I doubt we would have ever eclipsed 500 hp.  We documented the autopsy of that engine on our Youtube channel if you are interested here:  https://www.youtube.com/@TinIndianPerformance  Look under Ram Air 5 playlist….

Craig’s instructions with the new combo were to make try and make north of 600 horse with the intent to drive the car on the street.  He also wanted to take it to the strip on occasion as well.  We started off with a MR-1 cast iron block wanting to build a strong reliable street / strip combo.  We also decided to put a fair amount of cubic inches under the MASSIVE Ram Air 5 ports to help suck on those ports a little harder….we ended up making 714.4 HP at 6000 rpm and 675.5 lb ft of torque at 4500 rpm with a 1150 Pro System Dominator and 670 horsepower at 6200 rpm and 639 lb ft of torque at 4500 rpm with a 4150 Pro Systems HP 1000 carb.  We were VERY pleased with these numbers as the air the day we were on the dyno was ABSOLUTELY HORRIBLE! Weather station showed 87 degree temp, 70% humidity, 28.74 barometer with a correction factor of 1.102 AND 137 water grains!  One of the worst weather days we have every dynoed an engine for sure.

Looking forward to seeing this combo at the track!

The engine uses the following components:

  • Kauffman Performance MR-1 Pontiac block 4.250 bore
  • Scat 4.5″ stroke forged crank
  • 69cc PMD Cast Iron #44 Ram Air 5 heads – compression is 13 to 1 using 112 Sunoco Supreme fuel  2.19 intake valves 1.88 exhaust valves
  • PMD Stock  dual plane intake manifold
  • Oliver MAX 6.7 rods rods
  • Moroso Oil pan
  • Moroso 4 vane enhanced vac pump
  • Total Seal Rings file fit
  • King Rod and Main bearings
  • Ross 4.250 bore pistons
  • Durabond Cam bearings
  • Trend 3/8 Pushrods 9.7″
  • Custom Ground Tin Indian Performance Ram Air 5 solid Roller Camshaft by Militia Cams
  • Crower Solid Roller Lifters .842
  • Tin Indian Performance Complete Gasket Set with TIP-RM300 Viton ® rear main seal
  • .040 Cometic head gaskets
  • MSD Billet Distributor
  • Fire Core Performance Spark Plug wires
  • Scorpion 1.52 full aluminum roller rocker arms
  • NGK Spark Plugs
  • ARP Head Studs
  • Flow Kooler water Pump
  • ATI Balancer
  • Pro System 1150 Dominator carb / tested Pro Systems HP 1000 4150 style carb as well
  • 2″ spacer tapered spacer
  • 4″ custom Tin Indian Performance Billet-TEK Valve Covers with Custom Logo
  • Engine balanced and blueprinted
  • Dyno Tuned before delivery