FI vs 1800 head

[BammBamm]

What kind of performance change will my 82 FI 2.0L get if i swap it to a 1800 head?

[So Cal Mark]

you'll gain a few hp

[BammBamm]

a few as in 3hp or like 10hp?

[FiatMac]

a few as in 3hp or like 10hp?

At most expect about 2-3 hp if the breathing of the head were the same. However, the 1800 head has smaller ports and more shrouding of the valves, which means it will not breath as well as the 2000 FI head. So it might be a wash. In other words, I doubt that you will notice a difference.

[BammBamm]

i thought it was a big deal to put the 1800 head on a 2l motor. Does the 1800 head need to be ported and polished to make a real change?

[vandor]

The 1800 head does NOT have smaller ports. Actually there is one version that has larger ports than the 2000 head.
Using the 1800 head will increase the compression ratio from 8.1:1 to about 8.6:1, yielding maybe 2 hp.
However if one also adds the 1.25mm domes pistons the result will be ~9.4:1 CR.

[joelittel]

Which year 1800 head had the larger ports?

[BammBamm]

that is making more sense. yes what year has larger ports? I have two 1800 heads.

[vandor]

I think it came on some 74s. The ports are visually larger, but would definitely be able to measure the difference with a micrometer. However, the flow difference is very small, I don't remember exactly, but something like 5% better than the other 1800 head.

[joelittel]

Darn. I've got an 1800 head from '79. I was hoping you were going to tell me that I have a gem squirreled away.

[mpollock]

'79s were 2l, unless Fiat used some leftover 1800's for the early cars . . . which wouldn't be beyond belief.

[joelittel]

It's probably more likely that my 1800 isn't from '79.

The fun never ends

[BammBamm]

how much is a good 1800 head worth?

[BammBamm]

anybody know what an 1800 head is worth?

[BammBamm]

So my headgasket blew on the FI head so I decided to use my 1800 head. I had it inspected and machined. Plus did a leak test on the valves.
When i visually compared the combustion camber size, it looked considerable and it feels considerable now running. It feel like it picked some HP and revs faster. It sounds much more throaty and Im sure it will sound better when I pull off the catalytic converter today (i don't have to do emissions). In my mind it would be a clear decision to always use an 1800 head on 2.0L blocks..Im planning my next engine with ugraded cams and HC pistons.