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Discussion Starter #1
According to the rubbish haynes manual I have, there are 3 variations of the 1500cc flat 4

301.24 - 84 hp
301.28 - 95hp
301.46 - 105hp

What is the mechanical difference between the three, other than the increased compression ratio?

Thanks.
 

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According to the rubbish haynes manual I have, there are 3 variations of the 1500cc flat 4

301.24 - 84 hp
301.28 - 95hp
301.46 - 105hp

What is the mechanical difference between the three, other than the increased compression ratio?

Thanks.
301.24 - single carburettor
301.28 - twin carburettors and possibly different (more ovelap) valve timing
301.46 - twin carburettors, bigger valves and possibly different (even more overlap) valve timing

I think is about the gist of things, I'm sure others will know the differences definitively and/or in more detail.
 

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301.24 - single carb (actually 85 bhp I think, like it matters)
301.28 - twin carb double choke weber 361DFs, larger air cleaner, 9:5:1 compression ratio and different 5th speed gearing
301.46 - as 301.28 except different carburettor jets, revised induction pipework, higher lift camshafts and different cylinder heads
David Owen's book The Alfasud is a good resource.
 

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Thats the factory spec difference from designing because during production they were lots of variations depending stock. For example the were engines with 36'' carbs and there were others with 40'' carbs etc....
 

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also, im not sure but i think the single carb engines actually have a different head to twin carbs???

i can recall there was something like that?
 
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also, im not sure but i think the single carb engines actually have a different head to twin carbs???

i can recall there was something like that?
think that is right, i've been told before that the heads off a single carb can't be fitted to a twin carb car, different shape to the throats or something?? :confused:
 

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The first 'Suds used Heron heads, where the combustion area is formed by the dish of the piston crown. I used to think that all the single carb and 95 bhp twin carb models had this feature, but my 1.5 Ti has flat-topped pistons, so the heads must have combustion chambers. So I am not sure where the changeover to chambered heads occurred.

The 105 bhp engines definately had higher lift cams, and some used Dellorto DRLA36 instead of Webers.

My '78 1.5 Ti engine (single carb) must have been the same as my '82 Ti (twin carb), as both had flat-topped pistons, and one of my '78 inlet valves is actually performing very well in my '82 engine!

I'm not sure this is helping... :confused:

Lauren
 

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301.24 - single carb (actually 85 bhp I think, like it matters)
301.28 - twin carb double choke weber 361DFs, larger air cleaner, 9:5:1 compression ratio and different 5th speed gearing
301.46 - as 301.28 except different carburettor jets, revised induction pipework, higher lift camshafts and different cylinder heads
David Owen's book The Alfasud is a good resource.
Didn't the 301.46 or 105 green cloverleaf engine have a bigger inlet valve as well as the single lobe camshaft in the revised heads?
 

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According to the rubbish haynes manual I have, there are 3 variations of the 1500cc flat 4

301.24 - 84 hp
301.28 - 95hp
301.46 - 105hp
For 1.5 boxers, there is also:
305.04 - 84hp 33
305.20 - 95hp Arna (also listed as 90hp 33...)
305.08 - 105hp 33
307.34 - 105hp 33
307.50 - 96hp 33
307.51 - 95hp 33
310.16 - 95hp Arna

For the 1.7:
305.50 - 114hp Sprint
305.58A - 105hp 33
307.36 - 110hp 33
307.37 - 110hp 33
307.46 - 137hp 33 16v
307.47 - 132hp 33 16v Cat
334.01 - 129hp 145/6 16v Cat


I'll leave it to someone else to list the differences!!
 

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I want to put a 1.7 8v engine in instead.

What variations of the 1.7 are there?

Thanks :)

The one you want is 305.50. It's the one with twin carbs from the Sprint 1,7QV and the S2 33 1,7QV and has according to my informations 118 bhp. The came in two differetnt versions either with mech or hyrd tappets.
The other versions out of a 33 are injection engines. You can put carbs on them but to get the same bhp you need to modify it a bit. The compression is lower on the ie engine and they are all with hydr tappets.
I got a ie engine in my Sprint converted to carbs, raised compression, C&B cams and some other modifications. It puts out 140 bhp.
 

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Discussion Starter #13
Not bad, thanks again. How difficult are they to find (305.50) engines?

Also does anyone know what the flexible fuel pipe diameter is?

Thanks.
 

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Scrapyards... 1.7 with mech tappets is the best option as they produced 125hp instead of 118.
 

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I havent heard 1.5 eith hydraulics.. Can this be a transplant from a 33 with 1.4 capacity?
 
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