Street Manners

[agertz1]

Head flows 270 cfm./28"/.6" int. lift, feeding a 42.7" cylinder x 4. I believe the challenge is to have enough port velocity, for 95% street use ?
IR. intake to 4bbl TBI. I'm considering anti reversionary cones at the exhaust ports ? Looks like 15/8" primaries, 4 into one collector.
Thoughts ? Thanks, Art.

[PackardV8]

Those who know more will most likely suggest camshaft events, especially overlap, has as much to do with "street manners" as does intake CFM.

Also, vehicle weight, tire size, rear axle gear, number of transmission ratios.

A light street roadster with a five-speed manual is a very different combination than a pig-heavy AWD SUV with an automatic.

[agertz1]

Thanks, going in a Porsche 914 so about 2,200 lbs. 5 or 6 speed stick.

[PackardV8]

Thanks, going in a Porsche 914 so about 2,200 lbs. 5 or 6 speed stick.

IR. intake to 4bbl TBI.

Wasn't IR sequential EFI used on most 914s? That's the choice of most OEMs in performance applications and offers several advantages over TBI for your application.

[agertz1]

914 Inj. is mass, not sequential, not E85 compatible and where is the tuning map ? Type 4 block and crank, is where similarity stops.

[agertz1]

Batch fired.

[BLSTIC]

Those concerns are a computer and injector swap away from being solved though.

Have you run your proposed combination through an engine simulator? Even the simpler one are fantastic tools.

But back on topic, how much power are you trying to make? That's enough flow for about 270-280hp, and if you aren't trying to get that much you can sacrifice some cfm for decent velocity gains via port filling, which will improve the manners quite a lot.

Unable to advise on anti reversion location, but putting it near the port sounds like it would mess with the rest of the header too much.

[agertz1]

4 bbl.TBI on top of IR. manifold , possibly " FI Tech" brand, E85 compatible. Target is 270+ hp. Max hp. 7k+ ? Original 914 is 75hp. AR cones would be
a last resort. This build should have more torque/hp., everywhere over 1.7L.
Thank, Art.

[agertz1]

4 bbl.TBI on top of IR. manifold , possibly " FI Tech" brand, E85 compatible. Target is 270+ hp. Max hp. 7k+ ? Original 914 is 75hp. AR cones would be
a last resort. This build should have more torque/hp., everywhere over 1.7L.
Thank, Art.

[jsgarage]

Whatever you decide, move the computer if you find one that still works! Porsche doesn't make many mistakes but putting the 914 EFI computer directly underneath the battery was not exactly a stroke of genius.