Porting a type 4 head, Not much of a short side Options

[stownsen914]

The GT classes in PCA were designed to run 110hp per a liter

Making the 6 cylinders more competitive at any displacement than a -4

I believe PCA CR indexes aircooled 4's at 85 hp/L and 6's at 110. Edit - actually just checked, it's 90, not 85.


There was a fellow here on the east coast who ran a 914/4 in the GT classes a bunch of years ago, and did well against bigger cars. Usually outran them. Mostly his driving, to be fair. It can be done.

[brant]

The GT classes in PCA were designed to run 110hp per a liter

Making the 6 cylinders more competitive at any displacement than a -4

I believe PCA CR indexes aircooled 4's at 85 hp/L and 6's at 110. Edit - actually just checked, it's 90, not 85.


There was a fellow here on the east coast who ran a 914/4 in the GT classes a bunch of years ago, and did well against bigger cars. Usually outran them. Mostly his driving, to be fair. It can be done.

My memory tricked me again

So 180 hp 2L/4

At least 220 in a 2.0/6 has been done
Don’t know of any 180hp 2.0 fours out in the world

[Charles Freeborn]

The GT classes in PCA were designed to run 110hp per a liter

Making the 6 cylinders more competitive at any displacement than a -4

I believe PCA CR indexes aircooled 4's at 85 hp/L and 6's at 110. Edit - actually just checked, it's 90, not 85.


There was a fellow here on the east coast who ran a 914/4 in the GT classes a bunch of years ago, and did well against bigger cars. Usually outran them. Mostly his driving, to be fair. It can be done.

My memory tricked me again

So 180 hp 2L/4

At least 220 in a 2.0/6 has been done
Don’t know of any 180hp 2.0 fours out in the world

Seems optomistic to me too in NA trim.

[HAM Inc]

It's true that there aren't many 200hp 2.0's out there. But back in 2006 Jake and I collaborated on a SCCA EP engine that made 206hp at around 7500rpm's. It was legal, reliable and raced well. Was a turd under about 5K RPM's but it didn't see those revs in a race.

We also had 1.8 FP engine that made 186HP. It too was legal, reliable and raced well.

100hp/liter is doable with a N.A. T4 but it wouldn't be streetable.

[brant]

Those are numbers I didn’t know about

Amazing

[Charles Freeborn]

It's true that there aren't many 200hp 2.0's out there. But back in 2006 Jake and I collaborated on a SCCA EP engine that made 206hp at around 7500rpm's. It was legal, reliable and raced well. Was a turd under about 5K RPM's but it didn't see those revs in a race.

We also had 1.8 FP engine that made 186HP. It too was legal, reliable and raced well.

100hp/liter is doable with a N.A. T4 but it wouldn't be streetable.

I’d be interested in the specs of an FP / VP1 legal 1.8. I believe the max carb size is 40mm?

[HAM Inc]

It's true that there aren't many 200hp 2.0's out there. But back in 2006 Jake and I collaborated on a SCCA EP engine that made 206hp at around 7500rpm's. It was legal, reliable and raced well. Was a turd under about 5K RPM's but it didn't see those revs in a race.

We also had 1.8 FP engine that made 186HP. It too was legal, reliable and raced well.

100hp/liter is doable with a N.A. T4 but it wouldn't be streetable.

I’d be interested in the specs of an FP / VP1 legal 1.8. I believe the max carb size is 40mm?

The FP rules allowed 38mm venturis in 40mm carbs (we ran Dels), 42 x 34mm valves, any port work, any cam, 94mm x 66mm bore & stroke. LN Engineering was on board with the development too and supplied Nickies and JE Pistons. Foley exhaust. I spent a tremendous amount of time on the heads. Jake assembled and tuned it.

Nothing run-of-the-mill about either of the engines.

[ClayPerrine]

Is there anything in the rules that says you cannot run aftermarket EFI instead of carbs? A lot of those bad habits of engines with radical camshafts can be tuned out and made streetable with EFI.

[HAM Inc]

EFI was only legal with the O.E. system back then. Probably still that way today.

[ClayPerrine]

EFI was only legal with the O.E. system back then. Probably still that way today.

That is a bit stupid. Even NASCAR has gone to EFI on their cars.......

[Charles Freeborn]

EFI was only legal with the O.E. system back then. Probably still that way today.

That is a bit stupid. Even NASCAR has gone to EFI on their cars.......

The “P” in the car class stands for production as in “as produced” so the rules usually require things like intake type, displacement, valve sizes, etc to be stock or near to it. The vintage classes (where I plan to run) can be both more and less restrictive depending on the sanction body.
There are “open” car classes where you can run modern efi. Even NASCAR requires restrict or plates among many many other rules.

[Charles Freeborn]

It's true that there aren't many 200hp 2.0's out there. But back in 2006 Jake and I collaborated on a SCCA EP engine that made 206hp at around 7500rpm's. It was legal, reliable and raced well. Was a turd under about 5K RPM's but it didn't see those revs in a race.

We also had 1.8 FP engine that made 186HP. It too was legal, reliable and raced well.

100hp/liter is doable with a N.A. T4 but it wouldn't be streetable.

I’d be interested in the specs of an FP / VP1 legal 1.8. I believe the max carb size is 40mm?

The FP rules allowed 38mm venturis in 40mm carbs (we ran Dels), 42 x 34mm valves, any port work, any cam, 94mm x 66mm bore & stroke. LN Engineering was on board with the development too and supplied Nickies and JE Pistons. Foley exhaust. I spent a tremendous amount of time on the heads. Jake assembled and tuned it.

Nothing run-of-the-mill about either of the engines.

Many thanks Len. That’s pretty much as I expected. It will likely be my next engine. I’ll poach the 911 type fan, dry sump etc from the current one. Should make for a fun and competitive car in both FP and VP1. The gearbox will love it too.