Request for Camshaft Advice

Make it go fast! Kick it up a notch. Post tips in here.
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opus10583
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Your car is a: 1978 CS1
Location: Westchester County, NY

Request for Camshaft Advice

Post by opus10583 »

Hi,

One of Mark Allison's NOS 1800 shortblocks and Tobi's rebuilt '74 head are on their way to my mechanic.

I've already got a 32/36 DFEV feeding a single-plane intake manifold, and a 4-2 FIAT exhaust manifold funneled into a period Abarth exhaust system.

I'm working on getting a lightened flywheel and aluminum crank pulley.

I've neglected learning intake theory:

Whose and which cams do you recommend and then; Why?

(For now, it stops here.)

Thanks!

Mark
...Yes; I know what it means: Fabbrica Italiana Automobili Torino.

DOLCETTO: 1978 CS1; 10:1, DMS, 4-2-1...
ANDIAMMO: 2012 500 ABARTH

Acquista il Biglietto; Prendere la Gita! - Hunter S. Thompson
BEEK
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Joined: Wed Mar 24, 2010 10:45 pm
Your car is a: 1975 Spider
Location: clermont fl

Re: Request for Camshaft Advice

Post by BEEK »

with the low compression of a stock 1800 bottom end and a stock head, i wouldnt go more than 40-80 / 80-40 cams. maybe even milder, the biggest reason, is as you increase the camshaft duration you are costing dynamic compression, and can easily over cam the engine and cost performance. fiats stock cams are a pretty good grind for oem.
Automotive Service Technology Instructor (34 year Fiat mechanic)
75 spider
, 6 Lancia Scorpions, 2018 Abarth Spider, 500X wifes, 500L 3 82 Zagatos. 82 spider 34k original miles, 83 pininfarina, 8 fiat spider parts cars
son has 78 spider
So Cal Mark

Re: Request for Camshaft Advice

Post by So Cal Mark »

if you were going with my cams, I'd suggest our 285v grind. IMHO, 40/80 is too agressive for your setup. I offer a similar grind to 40/80 but I consider it as a Stage II grind
BEEK
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Re: Request for Camshaft Advice

Post by BEEK »

Agreed with mark, i should read up on his grinds as i have installed a few sets :)
Automotive Service Technology Instructor (34 year Fiat mechanic)
75 spider
, 6 Lancia Scorpions, 2018 Abarth Spider, 500X wifes, 500L 3 82 Zagatos. 82 spider 34k original miles, 83 pininfarina, 8 fiat spider parts cars
son has 78 spider
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opus10583
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Joined: Tue May 03, 2011 7:13 am
Your car is a: 1978 CS1
Location: Westchester County, NY

Re: Request for Camshaft Advice

Post by opus10583 »

Hi,

Thank you both.

Where would 'Midwest Bayless' 234deg intake only' fit in this discussion?

Thanks again,
Mark
...Yes; I know what it means: Fabbrica Italiana Automobili Torino.

DOLCETTO: 1978 CS1; 10:1, DMS, 4-2-1...
ANDIAMMO: 2012 500 ABARTH

Acquista il Biglietto; Prendere la Gita! - Hunter S. Thompson
fiat218
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Joined: Fri May 16, 2008 5:06 pm
Your car is a: 1969 124 AS spider

Re: Request for Camshaft Advice

Post by fiat218 »

Build that 1800 all the way to the max :)
I'm going as far as a 2.0 will let me, well that's my plan anyways
That's if my builder permits me too :mrgreen:
Jim
East Grand Forks MN
1970 Fiat Spider BS1 ( FOR SALE
1969 124 AS Spider
2017 Abrath
2018 Alfa Romeo 4c Spider
fiat218
Posts: 5745
Joined: Fri May 16, 2008 5:06 pm
Your car is a: 1969 124 AS spider

Re: Request for Camshaft Advice

Post by fiat218 »

BEEK wrote:Agreed with mark, i should read up on his grinds as i have installed a few sets :)
You are worrying me :D
Jim
East Grand Forks MN
1970 Fiat Spider BS1 ( FOR SALE
1969 124 AS Spider
2017 Abrath
2018 Alfa Romeo 4c Spider
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opus10583
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Joined: Tue May 03, 2011 7:13 am
Your car is a: 1978 CS1
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Re: Request for Camshaft Advice

Post by opus10583 »

fiat218 wrote:Build that 1800 all the way to the max :)
I'm going as far as a 2.0 will let me, well that's my plan anyways
That's if my builder permits me too :mrgreen:
Hi,

No... The NOS short block from Mark saves me a bag and a half of money, but the CR precludes anything truly adventurous, which is just as well; the 124 has certain limits of its own, and I've another car that's perfect for full-on hooning.

With the carb and exhaust already in my car, and lightened flywheel and pulleys, it'll rev and sound great.

Only still dithering on the cam set, not sure it's worth the expense given what I've learned.

Thanks,
Mark
...Yes; I know what it means: Fabbrica Italiana Automobili Torino.

DOLCETTO: 1978 CS1; 10:1, DMS, 4-2-1...
ANDIAMMO: 2012 500 ABARTH

Acquista il Biglietto; Prendere la Gita! - Hunter S. Thompson
So Cal Mark

Re: Request for Camshaft Advice

Post by So Cal Mark »

oh, it's worth it
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opus10583
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Re: Request for Camshaft Advice

Post by opus10583 »

So Cal Mark wrote:oh, it's worth it

Hi Mark,

How's that?

How's your 285V differ from stock and what's that going to give me on the street?

Thanks again,
Mark
...Yes; I know what it means: Fabbrica Italiana Automobili Torino.

DOLCETTO: 1978 CS1; 10:1, DMS, 4-2-1...
ANDIAMMO: 2012 500 ABARTH

Acquista il Biglietto; Prendere la Gita! - Hunter S. Thompson
So Cal Mark

Re: Request for Camshaft Advice

Post by So Cal Mark »

you'll notice a big difference in the midrange and top end. The engine will really pull from 3k rpm on up. The 285v has more duration and lift than the stock cams
narfire
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Location: Naramata B.C.

Re: Request for Camshaft Advice

Post by narfire »

.
opus10583 wrote:Only still dithering on the cam set, not sure it's worth the expense given what I've learned.
Opus, I suspect you have way more experience than myself with these cars, but After trying all kinds of set ups with my FI engine, I found the head is where the power is made with these cars. The cams I have, made the biggest improvement with the adjustable cam wheels and degree in the engine properly.
Pulls nicely from 3000 rpm and up.
Last edited by narfire on Sun Aug 11, 2013 1:34 pm, edited 1 time in total.
80 FI spider
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2017 Golf R ( APR Stg. 1)
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So Cal Mark

Re: Request for Camshaft Advice

Post by So Cal Mark »

the 274 cams in your engine are much milder than the 285 grind, and by design are intended to work with a stock motor with oem fi
BEEK
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Location: clermont fl

Re: Request for Camshaft Advice

Post by BEEK »

mark have you considered offering valves that are longer than oem for the reground cams. this way the valve shims will stay in the low end of the range? granted i have shims to 5.20 but they are heavy and most people dont have them. just a thought for you and your product line. i have tried lash caps (alfa shims) and actually broke one in the engine. trying to reduce valve train weight. years ago in a race motor.

cam boxes can also be milled, but this process is not easy either. most people who are adding performance cams are installing big valves. this way a longer stem valve could answer some problems
Automotive Service Technology Instructor (34 year Fiat mechanic)
75 spider
, 6 Lancia Scorpions, 2018 Abarth Spider, 500X wifes, 500L 3 82 Zagatos. 82 spider 34k original miles, 83 pininfarina, 8 fiat spider parts cars
son has 78 spider
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