AP mk1 twin turbo

Well, I have one of AP's first 5 stretch gt40s. I'm waiting on some time and parts, but here's the plan

427W, 9:1 CR with 225 AFR heads. Planning to run a mildish cam and let the turbos make up what the cam leaves on the table on the top end. Not looking for over the top ridicules unusable HP, but a tame manageable low end without the sacrifices in the top.

I have on order,

Mendeola SDR5 with limited slip, 3.55 gears
Man O War shortblock and AFR 225 heads, and a Holley HiRam intake.
Megasquirt 3, sequential and fan controls.
Garrett, (haven't decided) G25-600 turbos.
I'll do 180 degree snakes, but I have a special flange set up in mind so the left are on top and the right on bottom, then to collectors.
May be space limited, but I would like a 4 tipped muffler with a butterfly to cap the straight though outlet to mute the racket.
I think I can squeeze air to air innercoolers in the side scoops with fans controlled by MS3.

But honestly, this will sit on the back burner for the next few months. There's not a lot I can do until I have the engine and transaxel in hand.

No pics yet. It's just some glass in the shop now
BTW, I personally believe the added 4" in the door ad spider looks better than the original.

Yes, I've graduated for the pariah of the Cobra world with my Lone Starr (4" stretch) to the piranha of the GT world with a 4" stretch GT40.

I'm not one to worry about tradition or fidelity to the norms.
The cockpit is stretched. I may move the firewall forward and give some to the engine bay. I think the longer side window is a little obviously different, but I think an improvement.

Yes, it's an Active Power.

Here's a pic of it right after lifting off the trailer with the home made gantry and engine hoist.


Good phone call came today.

Short block is ready to pick up. But the heads have been pushed back to 7-30. Hope they're not pushed back again.

In the mean while, I've been gathering other goodies and working on a proper build table/dolly.

I have a 2x8 cradle I brought the block on, I need to grab it this afternoon to bring the completed shortblock home on rather than letting ot randomly roll around in my truck bed.
I was so close to doping twin turbo as I’m a forced induction person lol But I decided to go old school look this time around. Look forward to following this build.
I bought a pair of 12x12x3.5" intercooler cores, and I'm finding this will be a big challenge. I originally wanted the fuel tanks to go the full length of the gunnels, but I'm going to have to stop them at the spider and use that space for one of the cooler headers. This week I'll buy at least one turbo so I can see how they'll fit. I have a general layout in my mind, but I need the engine and transaxle in the hole to make sure my idea will work. I want to rotate the turbos to minimize the cold side tubing, and wasted space.

The other twin turbo I saw was a mark 2. Mine is a mark 1 and has a little less room. I also do want to squeeze mufflers in there.

My sketches are not much to look at, so until I can set some parts in place, I may not post much.



With turbochargers, you might not need mufflers. The turbos themselves are very effective in muffling the exhaust.
I did think of that. I will have some room back there and I guess it'll be the last component and I'll just do what I can.
Back in June after the ship date for the AFR head came and went, I called and got a new ship date of 7/30. That came and went, now they say 8/22.

Fingers crossed.



I’m curious about a couple dimensions with your 4” stretch version of the Arden/AP chassis & body. Being a taller and longer leg guy, I want to make my cockpit as big as possible. I’ll be scratch building my chassis and have several plans of which I’ll be referencing while designing & building my chassis.

1. What is the fiberglass side sill cover length? How about the length of the metal side sill support tube under it?

2. What’s the length of the bottom of the door? And the spider base behind it?

It looks like the front/rear clamshells are the same as the non-stretched so just trying to see where I might be able to design more cockpit room.

Thanks in advance

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To my knowledge, the front and rear clams are the same. All of the stretch is in the side covers, doors and spider. Where it's most obvious is the length of the side windows.

I'll have to throw a tape on it this weekend and report back.


To my knowledge, the front and rear clams are the same. All of the stretch is in the side covers, doors and spider. Where it's most obvious is the length of the side windows.

I'll have to throw a tape on it this weekend and report back.
That’s what I figured but wanted to confirm.

I know most side sill/fuel tank support length I’ve seen on plans are 63.5-65.5 inches however on my AP plans it’s showing 62 inches. My side sill covers are 66 total in length so am wondering if the AP cockpit could be stretched some and still use my existing side covers and doors.

Thanks for taking the time to confirm these measurements for me!


Thanks Brian! One more...what’s the length of the chassis side sill support tube under the side sill?

So far it looks like the door is taking the entire 4” stretch.