Just wondering if anybody has any figures as to have far you can go with a A15 engine naturally aspirated??? The old formula for 2 valve per cylinder atmo is like 100hp per litre so i'm told, making the A15 = 150HP by that logic... has anybody anywhere got past this figure without the aid of NOS or boost???
No i'm not looking at building one, just have a mate who carries on about them too much... i mean there not a SR20DET or anything lol :)
Thanks lads.

Rick Bone here in NZ campaigns a 207hp (at the fly) n/a A15 powered 1200 Coupe in S2000. There are very likely to be more powerful ones in Japan.

The sky's the limit.

That isn't a rule, but is a rule of thumb that most engines can shoot for with modest wealth...

Cost V HP is typically an opposite exponential relationship. Modest HP is doable with reasonable $$$'s. Getting every last bit of HP takes a scary amount of cash. Bang for buck a boosted A-series is the way to go. I think an A15 producing a reliable 150HP [at the fly] with a snail on the side is very doable with right choice of components.

What on earth is atmo?

a simple guide

$2000-3000 light mods typical of street car = 100hp
$4000-5000 a fair bit of cash on head work etc = 150hp
(?who knows 10k plus probably) money burning a hole... it doesnt even look like an a-series anymore = 200hp

200hp would be getting extremely difficult to achieve on pump fuel, and would require frequent rebuilds

atmo = atmosphere / atmospheric pressure ?maybe?

OR According To My Opinion ...

Sorry to spam your thread

Limit in race or stock a15?
I still find it hard to believe over 180hp is possible from an NA A series.
If there is evidence out there it surely hasnt made it on any forums except for word of mouth.
The best and most successful auto engineer in Victoria that has built the most successful under 2lt sports sedans in A and Ca formats Steve Newing has had an A series 1568cc at a reliable 160hp to beat 2ltr engined cars of all kinds. He had made over 176hp but wasnt as reliable/driveable.
His ca19de made 238hp at the flywheel with heavily developed 16v so 207hp is hard to believe.
2v pushrod 1608cc 207hp ate VERSUS 16v belt driven TC 1920cc 238hp ate.
I supposed Newings ca19de was limited for endurance also no peak hp and 34-36mm twin inlet valves is quite an advantage. Well we ever see a dyno sheets from industry accepted dyno
or do we need to when the advantages for a CA is so great?
Even the best alfa and twin cam 8v engines at 2ltr only make 215hp ate in full race trim
and they superior engines to the A. Top of the range sr20ve, neo sr16ve and honda K series are around 205-220hp and they are serious hardware.

He didn't say it had to be reliable, nor long lasting.

A club member recently told us his A-series made 200+ HP with alcohol. Good for short sprints.