Shaving the block, 2L

[BoHejlskov]

I'm rebuilding a 2L that comes from a euro Argenta. Flat top pistons and 122 HP. It's my first rebuild, hence the question. After talking to forum member 131lover (who kindly sold me the engine cheap) I'm tempted to shave some millimeters off the block to improve compression. I will be shaving some off the flywheel as well, but keep the stock cams and injection.

How much can I shave off the block and what does it do to the timing belt? Do I need other pulleys?

[So Cal Mark]

shaving the block will change the relationship between the cams and crank, not the best way to increase compression

[vandor]

You can shave some off the block, but not a few mm!
You need to measure how far up the pistons come. Usually the top of the piston (not the piston dome) will be below the deck of the block. The piston should come no closer to the head than 0.75 mm. Knowing the thickness of the headgasket, you can calculate how much you can shave from the block.
I shaved 1.25mm off my block and it increased the compression ratio from 8.9:1 to 9.8:1. I think the Argenta engine originally had a 9:1 CR, so make sure you can get gasoline with enough octane to work with whatever compression ratio you end up with.

For every mm the block is decked (or the head is shaved), cam timing is changes by 1 degree.

[131lover]

Hi!
The Argenta pistons are block level and the pistons are flat with 1cc valve pockets, with a 1,3mm gasket(std Argenta is 1,5mm) and 0,5mm shave there should be 0,80 left between head and block and 0,5 degree out from stock timing!
Am I right?

What would the comp ratio be for this build?
Cheers
Alf 131lover

[BoHejlskov]

I believe the Argenta engine has 9:3 compression (correct me if I'm wrong). We have no worse than 95 octane here in Sweden, and 98 is available on 90 % of all stations.

I don't want to build a racer, just a cheap rebuild with a little more umps than the usual Spider.

[narfire]

[quote="BoHejlskov"]I don't want to build a racer, just a cheap rebuild with a little more umps than the usual Spider

perhaps source a 1800 head and have that worked over a bit. I found with my 2L FI engine the most noticable improvement came with head work, cams and adjustable cam wheels. Perhaps consider taking 5-10 thou off the head instead of the steel block if you want even more compression.

[BoHejlskov]

I am in Europe. The heads we have here are different than the asthmatic ones you guys have in the americas. My car came from the US in 2008, and one of the reasons I wanted a new engine was to get the car to european standard. The engine is 122 HP stock. I don't think that a 1800 head would do any difference.

[bradartigue]

The heads we have here are different than the asthmatic ones you guys have in the americas.

Nonsense. Measure a few dozen "euro" heads before you make a statement like this.

Power in the stock FIAT motors comes from the intake/fuel system FIAT mounted to them. The same 2L motor that produces 102HP with fuel injection produces 81 with a crappy 23mm Weber and upwards of 120HP with well tuned twins or big single Webers. After that you have to get into compression increases, through pistons (not heads) that have domes.

If you shave a block you have to match a head to it, then match up every other part in between. You have a custom engine that will be a bitch to tune.

You already say you produce 122HP with your block, rebuild it to stock and enjoy it

[vandor]

1800 heads are uncommon pretty much everywhere but the U.S. Fiat only produced the 1800 for 5 years.

[124JOE]

whats the reward on an 1800 head?
price wise?

[toplessexpat]

Nonsense. Measure a few dozen "euro" heads before you make a statement like this.

But Brad... isn't there that very rare car that was only sold by that special dealer deep in the heart of Italy that had a special "euro" head, with special "euro" cams, special "euro" carbs, and a special "euro" exhaust that produced a gazillion horsepower whilst still running at >30mpg. I think it was the Spider Unicorn Edition?

A

[djape1977]

get an engine head from fiat 132 1600(1585ccm, not 1592ccm), 1800 or supermirafiori 1600, argenta 1600 (argenta 100), ritmo 105, regata 100s... that will significantly increase compression ratio without shaving the block. you should be able to find some of these in sweden

euro heads and cams? well i don't know what fiat did to decrease power so much for US market, but when you were getting less than 100hp from fuel injected 2 litre 124's, over the pond we got 122hp in our 132's and argentas. fortunately, US spec fiats are very rare and far between over here. to anyone looking to increase HP without spending too much cash - buy an engine from european fiat

[toplessexpat]

euro heads and cams?

Apologies - I was trying to be funny I think it was settled a long time ago that there was no difference and the existence of a magical special european model of those components was a myth..... US spec had lower power because of the additional emissions type of things...

[RRoller123]

Isn't lower CR the "problem" here in the US versus the Euro models?

[vandor]

... but when you were getting less than 100hp from fuel injected 2 litre 124's

A FI spider is rated at 102 Hp. The same car with no converter was rated at 105.
My guess is that the only difference from the US Spider and the Argenta engine is in the compression ratio and exhaust.
I have bought cams in Europe from TC engines, and they degreed out to be the same as in US spec engines.