Sanity Check On My Build

[Steve K]

The TKO600 will make it an easy driver but I think you might want more gear with that cam. I run 4.10's in my Camaro and it's the minimum I'd run with my 427. I'd say build it for max power, use a carb, gear it up and have fun. I'd also recommend a Tunnel Ram but that's more an addiction issue I have.

[BLSTIC]

I'm inclined to go for EFI. You'll need it to make it clean and drivable, and "more big" doesn't necessarily mean "more pig" when you don't have booster venturis or manifold wet flow to worry about. A sequential port EFI with modern well-atomising injectors will go a long way in making a big cam drive nicely (bonus points for being able to adjust the injector timing).

Between that and making sure your headers are good (read Calvin Elston "exhausted" threads for details, or even 8-4-1 if you want sexy flat plane crank noises that fit your chassis, with the added bonus of reducing cylinder to cylinder tuning variations A LOT) you can tame an awful lot of cranky out of an engine.

Having temperature correction for ignition and the ability to run a knock sensor is also nice for assorted reasons (although I don't think the average tuner and EFI system is really capable of using the knock sensor for more than safety, the temperature correction will help stop the pinging in traffic on a hot day without compromising what it does under ideal conditions).

[Topsp33d]

I'm inclined to go for EFI. You'll need it to make it clean and drivable, and "more big" doesn't necessarily mean "more pig" when you don't have booster venturis or manifold wet flow to worry about. A sequential port EFI with modern well-atomising injectors will go a long way in making a big cam drive nicely (bonus points for being able to adjust the injector timing).

Between that and making sure your headers are good (read Calvin Elston "exhausted" threads for details, or even 8-4-1 if you want sexy flat plane crank noises that fit your chassis, with the added bonus of reducing cylinder to cylinder tuning variations A LOT) you can tame an awful lot of cranky out of an engine.

Having temperature correction for ignition and the ability to run a knock sensor is also nice for assorted reasons (although I don't think the average tuner and EFI system is really capable of using the knock sensor for more than safety, the temperature correction will help stop the pinging in traffic on a hot day without compromising what it does under ideal conditions).

Yea I really wish I could run a bundle of snakes but the application is a 67 mustang and the biggest I could get was 1-7/8 header on the 9.5 deck motor, headers are the real bottleneck here and maybe that should be taken into account. Totally possible to dump a few more grand on a bigger set I guess. I agree with the efi sentiment regarding ease of tune, once everything is mapped out and it’s running by itself it would be super nice to not have to worry about heat or vapor lock or knock…

Initially I chose the efi intake as a max effort street build hoping that the ports wouldn’t turn it into a pig while being big, but they are quite large: 5” csa at the plenum working down to 3” at the gasket. My heads have an average csa of 2.4” with a throat of 1.79” diameter so there is a large amount of taper involved. The heads have a ton of room on the top to port match but it’s still drastic for a total length of 9.6875 on the short runners (12.312 on the long runners). Actually I just did the math and it’s only 1* taper?

Update on combustion chambers: I received my burette and poured with accuracy a 52cc chamber. Unfortunately that means something will have to give regarding pistons or chambers. I’m still waiting for the block to come back from line honing the main journals before we can check deck height but I will pour the pistons next and will reassess the issue.

Now I am considering to port the chambers and open them up to an LS7 style chamber, they have similar valve angles but the LS heads have much smaller quench pads and more combustion area. Once I have the pistons back I will make templates of their dish and compare it to the chambers to see if I can make a mirror image to gain cc, maybe I should make a different post regarding that

[BLSTIC]

The 8-4-1 doesn't necessarily need to take up "bundle of snakes" kind of room, around the engine at least. Unfortunately the total length still ends up being fairly long so you'd need to run a sim to see how bad or if it's actually out of tune.

If I was building an exhaust for mid-range and sexy flat plane crank noises I'd do it, but absolute peak mid range would be crossovers (I think the two very small 180 degree firing chokes would be a benefit over the 8-4-1 which can't have an even firing choke before the final collector). I don't think either design would work for top end of you've got a decent redline (tuning length shorter than what you can actually join the pipes at, especially in a chassis). I'd have to run sims to see but don't have the time at the moment.

This is the z06 one from celeritech

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