TC Head replacement 131 -> Regata 90si

[oebb]

Hi all!
New on the forum. I've got a Fiat spider -82 with the original f.i. engine replace with a carbed 2l TC from the U.S. 131 (assumingly a -79 w engine code 132.c2.04). I'm aiming at a around 150 hp and from what I've read is the head on this block (with id 4406111) very restrictive and best used as a book stand or similar.
I've got the possibility to by a "Regata 90si -89" TC carbed 1,6 l engine with the following data from the seller (not 100% trustworthy: engine type 149c2.000, head id 149888p). From what I've found out should the "Regata 100s" head be a good starting point with better compression, bigger valves and good porting possibilities. Does anyone know if this is valid also for the "Regata 90"-head that I've stumbled over?

Regards

/Mikael

[Guy Croft]

Mike, hi

I'm glad you posted because you've read the wrong books/forums. There is a lot of nonsense talked particularly in the US about the merits of the TC heads. I will assume that you would approach a conversion in true GC style - ie: do it properly as outlined over and over on this site.

But for the record I want to say this:

If a few more people actually signed up for my Head Prep DVD this would stop. The reality is (as I demonstrate real-time in the film) that any of the TC heads can be made to 'fly' by alteration to the chamber, ports and valve-seat setup and I neither condone or encourage the practice of 'swapping' heads (which invariably implies - I read this a lot - swapping one carbon-coated dirty old head for another in fond expectation of a percentage point increase in CR or 'cheap' power gain with reckless (ignorant?) disregard for any kind of survivability/reliability - or oil consumption. These TC heads are upwards of twenty seven years old!). To be more precise I have a 'sense of humour failure' when people talk to me about 'thinking of swapping the head ...' blah blah.

Nuff said.

The only exception to the head interchange (not 'swap' - because I ALWAYS - for the best of reasons - recommend a head overhaul prior to fit) would be a sound alternative to big valve conversion by using the 43.5mm inlet valve head in place of the 42mm version. That does make good budget sense, though I wouldn't walk far to get a 130/105TC/Delta head because it doesn't take much effort to convert it.

GC

[oebb]

OK, thanks Guy for straiting this out.
In any case, I need a head to work on - so from this perspective I guess the Regata head is as good as any. Does this head have the 43.5 mm inlet valves?

Regards

/Mikael

[Guy Croft]

Maybe but I honestly don't know, I'm not that good with the Regata/Tempra models because they were never popular in the UK and most were junked.

Some bright member who's good with model numbers might know?

I think there is 'early' and 'late', the latter being the rather useless 'reversed' port type.

GC