Carbs heads cams manifoldss oh my lol

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OffThaHorse

Carbs heads cams manifoldss oh my lol

Post by OffThaHorse »

Can anyone give me a brief rundown on what came with what when it comes to years, carbs, heads manifolds etc.


What swaps are beneficial and why.
In what instances does one need to upgrade the exhaust manifold or exhaust system.
How do different carbs and heads affect fuel economy and performance

I tried to search but i get so many different threads that just mention my keywords it ends up taking all of my time lol. Reason is they are all good reads but none are relevent to my original question.


Thanks in advance
dmwhiteoak
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Your car is a: 1972 Fiat 124 spider
Location: White Oak Tx

Re: Carbs heads cams manifoldss oh my lol

Post by dmwhiteoak »

Check out 124joe 's thread ,kick it up a notch. I don't know how to put it on here for you but it's not hard to find.
Dennis Modisette

1972 124 Spider
2003 Chevrolet Z71
2007 GMC Yucon
narfire
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Your car is a: 1980 124 spider
Location: Naramata B.C.

Re: Carbs heads cams manifoldss oh my lol

Post by narfire »

Search Brad Artiques site. He has a great rundown on the engine and carbs and simple things to give the car a bit more pop.
80 FI spider
72 work in progress
2017 Golf R ( APR Stg. 1)
2018 F350 crew long box
OffThaHorse

Re: Carbs heads cams manifoldss oh my lol

Post by OffThaHorse »

Whiteoak i pulled up that thread and it badically lists his experience with his choice of parts...doesnt go into any comparisons or details on WHY he chose what he did


Narfire ill google brad artigue

Thank you both for the help
So Cal Mark

Re: Carbs heads cams manifoldss oh my lol

Post by So Cal Mark »

economy and performance are two ends of the spectrum. If you make more power and use it, you won't get good fuel mileage
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kmead
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Your car is a: 1969 850 SC 1970 124 SC 85 X19
Location: Grand Rapids, MI

Re: Carbs heads cams manifoldss oh my lol

Post by kmead »

It depends on a lot of things. What engine are you starting with?

To get rid of the early vacuum operated carb you want a 1.8 flat plane intake manifold which flows better than the dual plane manifold. This allows you to use a large number of progressive carbs or a synchronous carb.

If you want real performance you will want the IDF manifold with dual IDFs that march your engines state of tune.

If you want a life of relative ease, some form of fuel injection starting with the OE system, the Vicks solution or roll your own injection system of which there are a bunch.

You will want the dual down pipe exhaust manifold if your car has the toilet bowl single down pipe exhaust manifold. Or go with a tubular header which generally is no better than the factory twin down pipe manifold. The exception being the well documented gains on gets with Marks manifold.

I would stay away from the OE Legend turbo set up as it represents really old technology that is easily bested today with the many parts available to you.

It really gets down to where are you and where do you want to go. Most of the factory parts were related to meeting emissions standards due to the time period, so most of the parts from the various years of standard parts will have little to no performance improvements. You need to go aftermarket or Euro OE parts to see much of a gain.

I also would suggest reading Brads well researched booklet and the then start looking at Guy Crofts web site for more knowledge as well as several other web sites like 124turbo.
Karl

1969 Fiat 850 Sports Coupe
1970 Fiat 124 Sports Coupe
1985 Bertone X1/9
BEEK
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Your car is a: 1975 Spider
Location: clermont fl

Re: Carbs heads cams manifoldss oh my lol

Post by BEEK »

ok, the best assembly of completly stock parts. the only reason im posting this is i have done this before for a "stock" racing series, there is 2 options for heads, ill explain as i go.

first, bottom end
2.0 block, use 1800 pistons if you have them, the smaller fly cuts do increase compression. now if there is room in the budget, but not "stock" buy high compression pistons.

head. use a 1592 or 1756 casting. the smaller combustion chamber will again help increase compression. now if you can get a 1608 casting the ports are much better on that casting, but the front water jacket will need a small amount of aluminum welding to make it compatable.

cams, use any they are all the same "stock"

use a single plane intake from a 1800, and a 34dmsa carburator, unless you have money for a larger one.

use the electronic ignition from a 2.0 it works very nicely

use the 4-2 exhaust manifold and down pipe.

again this is just one way to do this. others may have tried something else, im not saying this is the only way to do this. but worked well for me. also a stock 1608 with 9.8-1 pistons with the 34dmsa was a beast too
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
OffThaHorse

Re: Carbs heads cams manifoldss oh my lol

Post by OffThaHorse »

ok so i checked and i have the 32AFA carb on a single plane intake manifold and a 1756/1995 head?

the casting number on the head was FF 134 AS6C 4372291, which using atriques guide points to a 77 spider.

i was not able to find the block casting #
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seabeelt
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Re: Carbs heads cams manifoldss oh my lol

Post by seabeelt »

I think it is down by the oil filter /fuel pump area
Michael and Deborah Williamson
1971 Spider -Tropie’ - w screaming IDFs
1971 Spider - Vesper -scrapped
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1972 Spider - Tortellini- our son's current
OffThaHorse

Re: Carbs heads cams manifoldss oh my lol

Post by OffThaHorse »

Ok so the block is a 1.8 after all...

So after reading artiques guide im more familiar with the stock carb options. However i see mention of 34/36 and other type of carburetors on here alot.

I also see mention of 1608 heads alot.

Are 1608 heads desireable or more powerful? This will be a hobby vehicle more than a weekend cruiser so id like to stay on the performance side (not radical) more than the economy side. Still want to stay fairly reliable though.

At what point should you upgrade cams valves etc?

How big of a performance difference are dual carbs alone and as far as potential,theoretically how big of a difference is there between dual carbs and a bigger single carb?
So Cal Mark

Re: Carbs heads cams manifoldss oh my lol

Post by So Cal Mark »

you really need to package upgrades together to get the most benefit. If you don't set some parameters you'll end up with a engine that doesn't perform like you expect. You'll have a mish-mash of parts that may or may not be the best combination. Decide the rpm range your motor will operate in and the level of performance you desire,the budget you're comfortable with then your question can get some specific answers.
OffThaHorse

Re: Carbs heads cams manifoldss oh my lol

Post by OffThaHorse »

I've been mulling this over for the past few days, also doing some reasearch. (i quit my job so i can wish, but cant quite act yet hope to have something lined up soon.)

I am leaning torward low-mid range power. Something torquey, zippy, quick as i saw someone else call it. Im not exactly worried about winning drag races or going Ricky Bobby fast. The car would most likely never see anything past 95mph.

I know this is probably close to impossible with the low-mid power desires, but id like to at least get comparable economy to our Cadillac SRX or my Cadillac Allante (15 mpg on the SRX, and 18 mpg on the Allante)

Budget-wise...id say probably $1000 max
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