Alfa Romeo Forum banner

1 - 15 of 15 Posts
P

·
Guest
Joined
·
0 Posts
Discussion Starter #1
evening lads, I have a 1.6 hydraulic tappet engine out of a 145, I am in the process of converting to a twin carb setup.

the carbs are (or will be) jetted for a 1.7, and when it goes into my 33 obviously the CAT will be gone. Standard air filter with a custom exhaust.

Question is, with standard internals what BHP should I expect from this configuration? I drove the 145 before I stripped it and it just felt (and sounded) choked so I'm hoping the decat and carbs will give me a little belter:)
 
P

·
Guest
Joined
·
0 Posts
Discussion Starter #3
120? good stuff! Erm, at the risk of being a t*t what does oversquare mean?
 

·
Registered
Joined
·
1,047 Posts
Don't Think you are getting 120 bhp. I would say 105 maybe 110 bhp. We converted a 1,7 ie to carbs. It gave 110 bhp with a crossover manifold.
 

·
Registered
Joined
·
263 Posts
'An engine is described as oversquare if its cylinders have a greater bore diameter than its stroke length'

the 1.6 in the 145/6 is 1596cc as opposed to 1495cc - 1.5l, or 1712cc - 1.7l. Possibly a factory mixing of crank and pistons from the 1.5 and 1.7 to make a 1.6. (?)

the 1.5 mech tappet made 105 HP standard, and the 1.5 IE 33 made 11 HP standard, so think it's fair to assume the 1.6 will mek a little more.

the 145/6 was heavier than 33, so some attempts were made to wring a little more HP out of the boxer before they went TS...

once there were lambda sensors in the cars tho, HP figures all got a bit vague with many regional variations..
 

·
Banned
Joined
·
10,277 Posts
No kidding !
I always thought that the 16v on carbs would give well over 120 bhp !

Based on the fact that the engine gives out 132 bhp on a catalyst model and 137 on a non catalyst model, also based on the fact that you can use a 1.5 engine flywheel instead of the 16v wich is lighter, sinse there is no need for a crank sensor.

Would expect it to give around 140 with a good tune of the carbs.

Are you sure about these figures guys ? I know some other owners got up to 160bhp with high lift cams and carbs only !
 

·
Registered
Joined
·
2,788 Posts
It's a 1.6 8v folks, not a 16v. I'd say you should see 110/115 with the carbs and exhaust jim.

The 16v from the 145/6 will give up 140 with carbs.
 

·
Registered
Joined
·
1,047 Posts
'An engine is described as oversquare if its cylinders have a greater bore diameter than its stroke length'

the 1.6 in the 145/6 is 1596cc as opposed to 1495cc - 1.5l, or 1712cc - 1.7l. Possibly a factory mixing of crank and pistons from the 1.5 and 1.7 to make a 1.6. (?)

the 1.5 mech tappet made 105 HP standard, and the 1.5 IE 33 made 11 HP standard, so think it's fair to assume the 1.6 will mek a little more.

the 145/6 was heavier than 33, so some attempts were made to wring a little more HP out of the boxer before they went TS...

once there were lambda sensors in the cars tho, HP figures all got a bit vague with many regional variations..
Here the 1,4 ie made 90 bhp 1,5 ie 95 bhp and the 1,7 ie 107 bhp.
The 1,6 ie in the 145/146 is a 1,5 bore with a 1,7 crank. Here it made 103 bhp.
The engine in my Sprint is a 1,7 ie converted to carbs. Before tuning it with cams, higher compresion etc it made 110 bhp with a crossover manifold on a dyno.
All 8v ie engines have lower compresion than the carb versions. 9:1 vs 9,5:1.
I really don't Think you Will get 120 bhp on the 1,6 with the carbs conversion alone.
 

·
Banned
Joined
·
10,277 Posts
well, although the compression ratio is pretty low at 9:1, he might get 115 given that he will bypass all electronics, vacuums and air flow meter, as well as the catalyst.
Is the engine with hydraulic tappets ?
 

·
Registered
Joined
·
1,047 Posts
well, although the compression ratio is pretty low at 9:1, he might get 115 given that he will bypass all electronics, vacuums and air flow meter, as well as the catalyst.
Is the engine with hydraulic tappets ?
Yes its with hydraulic tappets.
The only way to find out is to put it on a dyno but why would a 1,6 make more bhp than a 1,7?
 
P

·
Guest
Joined
·
0 Posts
Discussion Starter #13
It's a 1.6 8v folks, not a 16v. I'd say you should see 110/115 with the carbs and exhaust jim.

The 16v from the 145/6 will give up 140 with carbs.
Cheers for that Frank, I think I may have started a bit of debate here! Was hoping for a wee bit more tbh, but it'll be better than the 1.3!
 

·
Registered
Joined
·
2,788 Posts
The 1.3 with twin carbs is actually not too bad when it's running properly. I had a brilliant time on the healy pass in mine a few years back. You will see a noticible difference with the 1.6. If we ever get to the same meet, take a spin in mine, the 16v on carbs is a bit of craic ( peak power is waaay beyond where the redline should be:lol:)
 
P

·
Guest
Joined
·
0 Posts
Discussion Starter #15
The 1.3 with twin carbs is actually not too bad when it's running properly. I had a brilliant time on the healy pass in mine a few years back. You will see a noticible difference with the 1.6. If we ever get to the same meet, take a spin in mine, the 16v on carbs is a bit of craic ( peak power is waaay beyond where the redline should be:lol:)
You may regret offering me a drive of your 33 Frank!:thumbs:
 
1 - 15 of 15 Posts
Top