Race Engine Forum UK

After experiencing a blown head gasket due to detonation on my 1608 engine I had to skim the head and block. Inspired by the “Modifying and Tuning Fiat/Lancia Engines Workshop Copy” by Guy I took this opportunity to improve the performance.

At first I planned to overhaul the 1608 bottom end and to have the head modified by GC to create a fast 1608. I contacted Guy, dismantled / cleaned the head and send it off.

Wanting to create an engine that would give me trouble free operation for many years to come and the fact that I myself had driven the 1608 for 200.000 plus km’s (one complete overhaul in between) I changed my mind . I decided to try to find a new (old stock) engine rather than overhauling the old engine.
After many phone calls I found a NOS 132 type 1800 engine. When delivered it became clear that the low dome pistons would not deliver a decent compression ratio with the modified head chambers. So the scope of the project was expanded with a set of high dome forged pistons from GC.

As I was disassembling the NOS engine Guy was modifying the head and inlet manifold. Much to my appreciation he was sending daily updates and many pictures of his skillfull work.

Since receiving the head, inlet manifold and steel flywheel I have been doing the dry build, final build and installed the engine. I also had to change the bellhousing due to the change from 1432 type flywheel to 2000 type.

Final work is installing ancillaries and fabricating a cold air box.

I will post some more after making progress.

Charles

Good work and super post.

You must not leave the fuel pressure gauge in there, it must be used to calibrate the pressure and then removed! It can burst at underhood temeratures and set fire to the engine bay.

I very strongly recommend you make a sealed cold air intake - if you induct at under-hood temperature you will almost certainly get detonation and blow the head gasket and maybe damage the pistons and rings. I see this all the time.

Sorry!

Thanks Guy,

I will remove the pressure gauge after setting the pressure regulator. Working hard on a sealed ducted cold air box. I will not start up before finishing that. This project has been initiated by a blown head gasket on a very hot day when driving away after a short stop thus with a maximum amount of hot air under the bonnet. I definitely do not want to experience that again!

Sincerely,

Charles

MODEL POST IN EVERY WAY



GC

Great post and beautiful work by Charles - and GC of course!

I love the look of delight you had when you opened the box with your new head in it!

I'm very interested to see what you do about an intake box. One day I may succumbe to the temptation of even more power so downdrafts may be the way for me to go one day.

Keep up the good work!

Thanks Phil. I will keep the forum informed on the air box.

Charles

when you opened the box with your new head in it

There are days I wish I could do that..... open a box that has my new head in it :-)
Nice wording, guys.

Great report and a fine build Charles.

regards
Tom

Hi Charles

Great post- and interesting to see the amount of work going inot a car that is not "pure competiton". Just good tunnning practice and good engineering. Cracking project.

One question- perhaps Guy can answer- 1608 head on 1800 block? This requires mods to the waterways?

My understanding is the 1608 head has the best ports and valve sizes of a standard unit ( excpt for the 130 Abarth head) So the question is- for general road use- is it easier/better to mod a 1608 head waterways and small mods to ports etc, or go for an standard 1600/1800/2000 head and carry out more dramatic port work/valve work?

Nigel.

Hi Nigel,

Thanks for your compliment. The head is is not an original 1608 but a 1592 I bought NOS some 120k km's ago after experiencing a broken valve. At that time I had the engine re-bored, fitted 81mm OE pistons and did a normal overhaul.

You're quite right that fitting a 1608 head to a 84 mm bore engine would require modification of the head on the front coolant port.
As for tuning potential that's Guy's field of expertise but as I understand it the differences (except with regard to the 130TC head) are not significant between heads if you measure this by the amount of work that has to go in it for proper modification.

Best regards,

Charles

Small update as things have been slow down due to much needed work on my Landy S2 and some work in the house.
- I've installed adjustable cam wheels because I encountered some mis timing with the standard pulleys;
- Finished a remote air filter;
- As I damaged the header tanks nozzle on the radiator during hose attachment I decided to swap the OE rad for a custom build aluminum one;
- Installed a 123 electronic distributor, new (of course) leads and a new coil;
Worked on fabricating a cold air box by modifying the OE filter box. This is not finished yet (though having spent 16 hours already). I consider this design temporary as I don't like:
- the width restricting access to carburetor vacuum plugs, air correction screws, idle screw, dip stick etc.
- Sheet metal being prone to heat transfer and to fatigue cracking (these OE boxes are developing cracks ll the time after being in use for over 40 + years)
Supplier Down Under is working on a GRP design by which I will replace my current "design" when it is available.
Commissioning and first start up will probably take place in March 2016 because the "salt on the road" season is coming.

Charles

Are those 44 idf's? I think you bought them from the same supplier as mine.

Did you have to mod the shafts to get them to fit on the waffle manifold?

Looks like you have reduced trumpet hight. What gap do you have to the top of the air box?

I like your filter location. I was considering this for my stage rally car, but as the oil cooler is on he inner wing on that side it is not practical. I have gone for a more standard performance foam style filter, and will try and channel cold air to it.

Keep up the great work.


Nigel.

Hi Nigel,

Those are indeed 44's as purchased in Holland.
Yes I did modify the shafts and nuts on the centre between the carbs by grinding them down yup until the point they were not interfering anymore. At present I will install 40mm height trumpets leaving 27 mm off free space to the top of the box which should be sufficient.

I have also considered to position the filter under the left wing between the head light and the inner wing. Difficult to duct but achievable. May be an option for you? Maybe on the other side of the radiator and ducting as per fuel injection?
What's the status of your build?

Charles

Small update on winter activities. Modified OE air filter to air box finally ready. Disadvantage is that one cannot access vacuum ports to synchronize carburetors due to the size of the box.
First startup, cam bedding in and synchronizing will be done with K&N filters and hood removed to keep induction temperature as low as possible. After synchronizing and tuning idle mixture I'll install the air box.
Ducting hose to filter, as shown on pictures, has been replaced by a proper one now.
Though I'm stoked to start it up I'll have to finish a living room refurbishment first and so first start will be about two weeks from now.
Will start by removing the belt and priming the oil pump again with a socket on an electric drill, install radiator, top up etc. Then start a well thought off commissioning procedure as derived from the GC manual.

Impressive.

GC

Congratulations !

I am most impressed.

Will you dyno the engine ?

Rgds

Miro