'67 Jag Trans Am/ GT-1

[Mike Motage]

Carey, I've got a 5.3L flat head (combustion chamber) to start with. It will be bored a lot and have new pistons with an 8.5-1 Comp ratio. I will fabricate a swoopy intake and stainless exhaust system. I'll probably install as large of valve as the seats will allow, along with port work. It will also have a dry sump oil system, 5 speed manual trans. I'm also going to use an aftermarket EFI system.

[mr.c]

Mike: You probably already know this. It was common on these engines to drop valve seats if the engine got too warm. Staking in the seats would be a good plan. If a seat drops it takes out the whole top of the motor. I have a core or two that experienced the dropped seat. It knocks the cam out and everything in between.
Do you have a flow bench? Was that what you did at Roush? I have not flowed any V-12 heads but did a LOT of twin cam sixes. I machined the heads and pressed in fuel injection seats which were for larger valves. The larger valves allowed me to find the best approach angles and widths. Those angles and widths were very critical to flow because the ports were lousy. On the six cylinder engines, they flowed the best without increasing the port size. I often thought that they would flow better with a smaller than stock intake port. I used Isky cams and they made for a really stout racing engine.
Forced induction might not be quite as critical on port/valve flow. It should be great fun. I am anxious to see what you come up with.
I have a T56 six speed that I need to adapt to one of my V-12 engines. Probably in the XJ-S convertible. I am sick of automatic gearboxes.

[Kerry Pinkerton]

I'm drooling on my keyboard Mike. I really wanted a Jag 6 in my roadster but didn't think I could afford it so I spent probably more money on the 300HP heavily modified Chevy 250.

Your car is going to be awesome!

[toreadorxlt]

looking amazing

[Mike Motage]

Carey, I'm aware of the valve seat problems these engines were known for. This issue was caused primarily by the centrifugal advance seizing and result retarded timing. Running and engine with late ignition timing drives exhaust temps extremely high and will cause exhaust valve/seat and piston problems. The seats will be thoroughly checked. The porting will more of a blend job than true porting. My intention is to keep the engine mild but durable, using turbos to build power. I've a friend retired from Ford who involved in nearly every turbo program they had included Recent LeMans winning GTs. He'll determine the exact turbos and tells me 1000hp is a piece of cake with my program and components. I'll stay more conservative than that.

Kerry, thanks! I wish pictures could show the smooth sexy lines of the power lump and scoops along with the rest of the car. To me they add perfectly to an otherwise long anemic look of the original bonnet. Pic too close you can't see how well it's looks overall. Too far away to see the whole car lose the how natural the scoops look. I've spent a great deal of time hand planishing. I'm finding myself reinvigorated.

[Mike Motage]

I found a pic that gives a good perspective of the scoop asthetic.

[Mike Motage]

Hey Kerry, did ya notice your wheel in the background? It's a nice tool, best money I spent !

[Mike Motage]

A few posts back, you saw the brake light lense models. Here's how the lenses turned out.

[cliffrod]

Mike, what product is the blue material and where did you get it? Freeman's or ??

We've used a similar looking product for life molds. It cures without a lot of heat & picks up great detail without adhesion issues, like ripping out every hair after it scalds the (initially) willing model like gypsum products can do.... Kinda funny but only once.

[Mike Motage]

The company that I got my supplies, 2part silicone rubber and resin from is Alumilite. Their located in Kalamazoo Michigan and have a website that list their multitude of casting products along with many how to videos. They were very helpful!