Mike Simard, 427cid small block Superformance Cobra

Mike Simard · Post by **Mike Simard** » Sun Mar 26, 2006 1:23 pm

Name: Mike Simard
Vehicle: Superformance Cobra
Engine: 427cid Ford 351w based engine. Dart aluminum block, 4.125 bore 4â€ stroke. 10.5:1, AFR205 heads
Injection: Individual 56mm throttle bodies. 50lb Delphi injectors. MSII v3.0 with EDIS ignition.
Description: This has been a 6 month project, mainly because of designing and building the throttle bodies and hardware from scratch. I started with a manifold for Weber IDA carbs, milled the mounting bosses at 12 degrees to lean the stacks towards the center and create a straighter intake runner. Since I measured the components to the engine when I built it, I was able to lay it out in a CAD program. With the runner angle determined I drew injectors pointing at the center of the intake valve and designed everything else around that. It made for some complex fuel rails that cross each other and the distributor wasnâ€™t going to fit. The actual Megasquirt part has been fairly easy. The fuel pump relay seems to draw too much current to be switched by MS but other than that itâ€™s been a breeze. The LC-1 conked out during the installation so Iâ€™ve been tuning the old fashioned way until the replacement arrives, that surely builds character. The difference compared to the old carb is amazing. I expected the driveabilty but the overall power increase is a surprise. The one area of tuning that concerns me at the moment is the cranking pulsewidths and afterstart enrichment. The EDIS has been uneventful, it just started working immediately and has no issues. Magnecor supplied some custom plug wires, I couldnâ€™t start serious tuning with the junkyard wires that came with the EDIS. Iâ€™ll add some pics later.

Mike Simard · Post by **Mike Simard** » Sun Mar 26, 2006 2:26 pm

Yes, that's for crankcase ventilation. This car sees alot of track time, nothing generates oil coming out of everywhere like sustained full throttle blowby. The previous setup had a crossover tube between the valve covers along the firewall which worked well but didn't fit the throttle bodies. There was alot of work that went into the breather tubes you see, there are angled tube segments welded together that had to fit just right, but it does allow the motor to breathe without dripping oil. The tubing allows oil to fall out of the air, there's also some 'baffeling' inside of them.

Mike Simard · Post by **Mike Simard** » Thu Jun 22, 2006 12:16 pm

Dyno results! Here's the dyno test overlayed with an previous run with a single plane intake and 850 carb. It's the same dyno and the car is the same except for the induction system and compression which I lowered by .8 during the installation. The dyno run shows some missing that I have to diagnose but overall makes 50hp more than the old setup while falling close of a nice round 500 by 3 hp, sigh. The rpm range is about 2500-6200

Mike Simard · Post by **Mike Simard** » Fri Jun 23, 2006 6:19 am

Here's a pic of the aircleaner and new thermostat housing. I made a housing and gave it two 3/8 npt holes for the temp sensors for the ecu and gage. I like having them there and not on the manifold. making a new unit also allowed me to machine an o-ring groove to avoid using a gasket, it's very nice to not have a cursed gasket. the aircleaner housing is machined from a solid block and is just the right size to fit within the car's hood scoop which allows the trumpets to be longer, that was one of the reasons for having both banks angled towards the center. The element is a K&N.

Mike Simard · Post by **Mike Simard** » Fri Jul 07, 2006 3:07 am

Here are 2 pictures of the throttle linkage.

Mike Simard · Post by **Mike Simard** » Fri Jul 07, 2006 3:23 am

hmm...