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Can anyone advise realistic numbers for a GTA 1300 race engine?
Alleggerita says the Autodelta race cars peaked at 140bhp @ 8,000. A later comment says 145 @ 7800.
Yet there are cars currently advertised claiming 150 and 160, which seem huge for a 1300.
There is talk of revving to 9,000. Is that realistic?
The dyno on my new engine is showing [email protected] 7,700 which is consistent with original Autodelta number. I don't yet have torque figures but I am interested to know whether I should be happy.
Regards, Colin Wilson-Brown
 

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Isn't there a question of how the BHP is measured?.. SAE is higher than DIN so one can choose which ever fits his ego and whichever measure suits the day.
 

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Many years ago when I saw these engines run on the "Go-Power" dyno at Ausca, 135/140 corrected Hp was realistic. It varied a bit with cams used at specific RPM. Some preferred the cams that moved the torque peak down a bit. 9,000 rpm was a figure these engines could run up to, but the need fo this was to avoid a shift in corners, as design limited power increases to less than 8,000 rpm. At 9,000, there were 2 BIG problems. The oil pump capacity had been exceeded, and there wasn't much oil pressure. We spent considerable effort re-designing the pump for more high rpm volume, and succeeded to some degree with the pump below. It didn't lose volume capability until about 82/8500. The other problem was piston quench area, and that had to do with A/F ratios, ignition, compression and high rpm detonation. The best "almost" fix was oil squirters spraying the inside of piston crowns.
In short, it was NOT a 9,000 rpm engine, that could run to 9,000 if needed, but there were issues up there.
Here's an Ausca "forever" oil pump test run at speed on my lathe. Yes, I still build this pump. It's not inexpensive.
 

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Hallo ,
which engine ? the normal twinplug head with carbs or the narrow head with injection ? These are complete different engines !!!
 

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Can anyone advise realistic numbers for a GTA 1300 race engine?
Alleggerita says the Autodelta race cars peaked at 140bhp @ 8,000. A later comment says 145 @ 7800.
Yet there are cars currently advertised claiming 150 and 160, which seem huge for a 1300.
There is talk of revving to 9,000. Is that realistic?
The dyno on my new engine is showing [email protected] 7,700 which is consistent with original Autodelta number. I don't yet have torque figures but I am interested to know whether I should be happy.
Regards, Colin Wilson-Brown

What's not to be happy about ? I agree with 110 Vabene) .. These engines aren't designed to last long over 7000 RPM steady. They will drive all day long at 5500 but the exponential factors of physics will catch up and the sweet sound without torque will be expensive. I would treat that engine with respect.
 

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Given that Autodelta's dyno tended to read high compared to most dynos today you can be happy especially getting that hp at such low rpm.

With 67.5mm stroke it should last for a long time at high rpm.

Obviously Gordon has researched the limitations with regard to oil pressure at very high rpm.

I am personally familiar with one Autodelta 1300 GTA junior that was regularly shifted at 9,000rpm - not run steady - and it lasted forever.

Also familiar with a Balduzzi injected narrow angle 1300GTA that blew up when taken to 10,500 ...

Driven a Stradale at 7000rpm for extended duration with no ill effects ... it is still running today.
 

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"I am personally familiar with one Autodelta 1300 GTA junior that was regularly shifted at 9,000rpm - not run steady - and it lasted forever"

Same for a friend of mine who years ago raced his 59 1300 Veloce Coupe which he also normally shifted at 9000 rpm in races, once in a while 9500, depending on the circumstances. Engine was quite strong and lasted as long as I knew about it, a few years.
 

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My point was the 2000 RPM between 5000 and 7000 are the difference makers... 9000 ?? i'm not so sure. I know this much a hand grenade will not detonate if you hold the clip down.
 

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All I know is that he was successful in competing against bigger cars with greater displacement engines. And, the engine never had a problem in the half dozen or so seasons he raced but he did have to replace the clutch after every race, lol.

Of course, it had about 5 hp below about 4k rpm. Difficult to drive on the street, although we did that as well.
 

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Autodelta performance figures.

Can anyone advise realistic numbers for a GTA 1300 race engine?
Alleggerita says the Autodelta race cars peaked at 140bhp @ 8,000. A later comment says 145 @ 7800.
Yet there are cars currently advertised claiming 150 and 160, which seem huge for a 1300.
There is talk of revving to 9,000. Is that realistic?
The dyno on my new engine is showing [email protected] 7,700 which is consistent with original Autodelta number. I don't yet have torque figures but I am interested to know whether I should be happy.
Regards, Colin Wilson-Brown
Hello Colin,

Some Autodelta performance figures on Autodelta engines(1300 single and twinplug amongst them). The performance numbers for horse power are in BHP.

Ciao, Olaf

Also have a look at:

https://www.alfabb.com/bb/forums/gta-1965-1975/283985-engine-developments-autodelta-1960s-1970s.html
 

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