1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

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TimpanogosSlim
Posts: 237
Joined: Wed Feb 06, 2013 12:45 pm
Your car is a: 1977 124 Spider

1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby TimpanogosSlim » Tue Feb 03, 2015 3:34 pm

During some recent junk yard trips i acquired the head from an early '77 124 spider 1.8 and the entire long block from a '79 spider 2000 w/ fuel injection, including the FI manifold, plenum, and injectors. I also took the electronic distributor and some other parts to get my existing late '77 spider 1800 on the road again.

Initially i had been thinking that i would try my hand at DIY porting with the 1.8 head (under supervision from an experienced tuner / machinist), maybe have the head machined for the bigger valves some vendors offer, and of course have the head professionally built, probably with street cams.

And then put it on the 2.0 block, rebuilt as needed with OE style pistons.

It seems like maybe the 2.0 FI head breathes better? I have no intention of running 35 year old fuel injection technology and only took the intake and fuel parts with the dream that some day i could do a an all-out turbo build w/ a modern ECU.

Does a 1.8 carb manifold even bolt up to the 2.0 FI head?

If it does, would i get better bang for my buck using that head, cams, and high compression pistons?

Or was my original plan just fine?

For carburetors i have my choice between a 1.8 single plane manifold with a freshly rebuilt 32/36 DFEV or a pair of IDF 40's with matching non-waffle manifold, which need rebuilt, but came with linkage.

Thanks!

narfire
Posts: 3959
Joined: Sat Dec 27, 2008 2:14 am
Your car is a: 1980 124 spider
Location: Naramata B.C.

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby narfire » Tue Feb 03, 2015 5:17 pm

My opinion.
1.8 L head freshened up but left stock. Bolts right onto the 2L block no issues. 1.8L single plane intake with a 32/36 , 34dmsa or 34 adf carb.
The 4-2-1 exhaust from the 2L.
You will notice a difference for sure.

I sourced a 2L, put it on a stand and built it over a year when funds permitted and then swapped it into my FI car.
Nothing wrong with the 35+ year old FI. They still provide nice smooth power and fairly reliable.
Chris
Oh yea, the 79 should be a carb'd car, they went to FI in 80.
80 FI spider
72 work in progress
2017 Golf R ( APR Stg. 1)
2018 F350 crew long box

vandor
Posts: 3996
Joined: Sat May 23, 2009 1:23 pm
Your car is a: 1971 124 Spider
Location: Texas, USA

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby vandor » Tue Feb 03, 2015 10:01 pm

If you will retain the stock pistons then go with the 1800 head for a little more compression.
If you get new pistons that it will depend on the pistons which head you use. For example, we sell 8.8:1 compression pistons. You could use the 1800 head with those and get ~9.4:1 compression ratio.
We also sell 9.8:1 compression ratio pistons with a larger dome. With these one would use the 2000 head, so CR is not increased over the 9.8:1.
Csaba
'71 124 Spider, much modified
'17 124 Abarth, silver
http://italiancarclub.com/csaba/
Co-owner of the best dang Fiat parts place in town

TimpanogosSlim
Posts: 237
Joined: Wed Feb 06, 2013 12:45 pm
Your car is a: 1977 124 Spider

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby TimpanogosSlim » Wed Feb 04, 2015 12:54 am

narfire wrote:My opinion.
1.8 L head freshened up but left stock. Bolts right onto the 2L block no issues. 1.8L single plane intake with a 32/36 , 34dmsa or 34 adf carb.
The 4-2-1 exhaust from the 2L.
You will notice a difference for sure.

I sourced a 2L, put it on a stand and built it over a year when funds permitted and then swapped it into my FI car.
Nothing wrong with the 35+ year old FI. They still provide nice smooth power and fairly reliable.
Chris
Oh yea, the 79 should be a carb'd car, they went to FI in 80.


I should be more clear -- nearly everybody seems to agree that the fuel injected engines are good for passing emissions and fuel economy but are not so much fun as compared to a carbed version. My daily driver is a tuned up 2007 GTI that compared to a brand new 1980 spider 2000 with fuel injection has more than 3x the horsepower (mine does anyway), about 2x the torque, and does 0-60 in nearly half the time despite weighing half a ton more and getting the same mpg.

I'm not interested in having the peak of original equipment spider 2000 performance. And in Utah it no longer has to pass emissions. or safety.

However, if there is a turbo spider in my future, it will absolutely be fuel injected, and i want to try my hand at programming megasquirt or similar some day. So it's good to have the factory sensors and fuel rail and the intake manifold and plenum and throttle body don't look at all bad to me but i'll be using a maf, and a wideband o2 sensor, and different injectors. and it'll understand absolute atmospheric pressure vs. manifold pressure.

As for whether it is a 79 or 80, the yard says it's a 79 which means that the title probably said it was a 79. I didn't exactly inspect the vin.

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bradartigue
Posts: 2183
Joined: Thu Sep 20, 2007 2:35 pm
Your car is a: 1970 Sport Spider
Location: Atlanta, GA

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby bradartigue » Sat Feb 14, 2015 7:39 pm

I don't know anyone who would agree with that. The fuel injected cars have much better performance than any carbureted Spider. Out of the box, unmodified, the FI system simply blew the carbureted cars away. Smoother, faster acceleration, better gas mileage, far more reliable operation. If you don't get equal or better performance from the FI system than you do from your carbs, something is wrong with your FI system.

Your GTI has better acceleration than most cars made prior to the year 2000 - it will out accelerate a Ferrari 308 (1977) - but I seriously doubt you'd want to drive it at 140MPH. The comparison isn't fair or even sensible in terms of a goal - in the "modern era" engines, transmissions, and fuel management systems are designed as an integrated unit. You will never - ever - get the kind of performance from a Spider TC that you will out of your VW 1.8T or V6. You'd trade off so much for, say, top end HP that the thing wouldn't idle, or you'd trade off top end HP for acceleration, and so on.

These cars are OLD. By the 1980s they were old engineering - a 1960s design propped up with a 1970s fuel injection system. Expecting them to be comparable to any modern system is expecting too much.

TimpanogosSlim
Posts: 237
Joined: Wed Feb 06, 2013 12:45 pm
Your car is a: 1977 124 Spider

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby TimpanogosSlim » Wed Feb 18, 2015 6:19 pm

*shrug* I still have no interest in mastering Bosch Jetronic, let alone retrofitting it in my '77.

If i do an EFI build it will be megasquirt/microsquirt, so it can be a technology less than 20 years old and i can learn something useful, that i can use in another car.

It will also probably be forced induction, which is easier to do properly with a MAF than the barn-door air meter. The basic issue being that the vane air meters have no range past "all the way open".

As for whether i'd drive my 2.0T GTI at 140mph, people do, though that's near the top speed of the original designed operating range of the engine and transmission. So far I've only been up to about a buck 7, and it felt just fine.

All manner of insanity happens over on turbo124.com - even talk of 2L TC builds with in excess of 300bhp. Right now my nefarious plot involves figuring out if i can retrofit the relatively small roots-type supercharger that gave 1994-1997 toyota previa minivans 6psi of boost in their 2.4L I4. These are easy to acquire, and cost less than a TC turbo manifold without the turbo.

ORFORD2004
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Joined: Wed Mar 17, 2010 9:48 pm
Your car is a: 1983 PININFARINA
Location: Sherbrooke, Qc, Canada

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby ORFORD2004 » Wed Feb 18, 2015 6:57 pm

If you want to run turbo engine with a intercooler, you better use this intake http://www.ebay.com/itm/110840559154?_t ... EBIDX%3AIT
because the original intake take is air on the same side of the exhaust so you will need a lot of piping.
I used this intake with the throttle body and the fuel rail and injector. It's from lancia delta integrale.

131
Posts: 672
Joined: Sun Nov 14, 2010 1:13 am
Your car is a: 1982 131 Superbrava warmed 2.0 litre.
Location: Tasmania, Australia

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby 131 » Wed Feb 18, 2015 9:04 pm

ORFORD2004 wrote:It's from lancia delta integrale.


The 8v integrale manifold angles the throttlebody into the cam gear and must be modified to fit. A manifold from a Fiat Tempra or similar is not angled, making throttlebody fitment easier.
Mick.

'82 2litre 131, rally cams, IDFs & headers.

ORFORD2004
Posts: 1099
Joined: Wed Mar 17, 2010 9:48 pm
Your car is a: 1983 PININFARINA
Location: Sherbrooke, Qc, Canada

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby ORFORD2004 » Wed Feb 18, 2015 9:43 pm

That's what I did.
Image

garion
Posts: 508
Joined: Tue Sep 18, 2012 10:20 pm
Your car is a: 1979 Fiat 124 Spider
Location: Phoenix, AZ

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby garion » Thu Feb 19, 2015 1:17 am

I had an odd conversation through email with a particular vendor about megasquirt. I was talking with him about the idea of megasquirt and a throttle body to replace a carb, you could do a cheap 'upgrade'. No new intake, a few sensors (I think maybe just the O2 and throttle position?), some wiring, and off you go.

This is a direct quote from the email:

I'll save you some headache.
Megasquirt does not work on Fiats.


He then went into some rant of getting the original FI system, and that it would be better than anything megasquirt could do.

Down the road, I may try something like this. Though I was thinking more of individual throttle bodies, like IDF's.. Imagine the nice sound of the IDF''s with the advantage of FI?
--John
1978 Fiat 124 Spider (for sale soon)
1979 Fiat 124 Spider
2007 Audi A4
Blog: http://www.technobabelfish.com

lanciahf

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby lanciahf » Thu Feb 19, 2015 6:58 am

Nice! Do remember which throttle cable you used?
Thanks!
ORFORD2004 wrote:That's what I did.
Image

ORFORD2004
Posts: 1099
Joined: Wed Mar 17, 2010 9:48 pm
Your car is a: 1983 PININFARINA
Location: Sherbrooke, Qc, Canada

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby ORFORD2004 » Thu Feb 19, 2015 7:36 am

Nice! Do remember which throttle cable you used?

The original one. Just buffing the cylinder at the end to make it round and use heatshrink to cover it. No problem all summer.
And I run megasquirt . The throttle position sensor is from Volvo 850. A direct fit.

burgandy81
Posts: 371
Joined: Fri Feb 22, 2008 5:38 pm
Your car is a: 1981 FIAT Spider 2000
Location: Victoria, BC

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby burgandy81 » Thu Feb 19, 2015 9:44 am

I also run Megasquirt.

TimpanogosSlim
Posts: 237
Joined: Wed Feb 06, 2013 12:45 pm
Your car is a: 1977 124 Spider

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby TimpanogosSlim » Thu Feb 19, 2015 10:29 am

ORFORD2004 wrote:If you want to run turbo engine with a intercooler, you better use this intake http://www.ebay.com/itm/110840559154?_t ... EBIDX%3AIT
because the original intake take is air on the same side of the exhaust so you will need a lot of piping.
I used this intake with the throttle body and the fuel rail and injector. It's from lancia delta integrale.


Yeah it remains to be seen. The 2.0 EFI manifold doesn't look bad to me but I'd need an intercooler with both ports on the exhaust side of the engine.

A friend of mine with megasquirt / tuner studio experience was telling me how easy it is to use the microsquirt module intended for motorcycles, snowmobiles, PWCs, etc, provided that you have an existing electronic ignition like an MSD or the Crane Hi-6S i picked up cheap on ebay already. It'll drive 4 high impedance injectors and logic-level ignition, and a accepts a bunch of sensors. About the size of a pack of cigarettes. Less than $400 with an 8 foot wire harness.

I don't have the time or funds to start working on this monstrosity this year. This year i need to get the old '77 back on the road and will do so with the 1.8L and 32/36 DFAV already on it. But i need to get the 2.0 bottom end to the machine shop to see how deep i'm gonna have to go into it.

TimpanogosSlim
Posts: 237
Joined: Wed Feb 06, 2013 12:45 pm
Your car is a: 1977 124 Spider

Re: 1.8 head on 2.0 block or 2.0 head + block w/ big pistons?

Postby TimpanogosSlim » Thu Feb 19, 2015 11:21 am

garion wrote:I had an odd conversation through email with a particular vendor about megasquirt. I was talking with him about the idea of megasquirt and a throttle body to replace a carb, you could do a cheap 'upgrade'. No new intake, a few sensors (I think maybe just the O2 and throttle position?), some wiring, and off you go.

This is a direct quote from the email:

I'll save you some headache.
Megasquirt does not work on Fiats.


He then went into some rant of getting the original FI system, and that it would be better than anything megasquirt could do.

Down the road, I may try something like this. Though I was thinking more of individual throttle bodies, like IDF's.. Imagine the nice sound of the IDF''s with the advantage of FI?


I can't fathom how megasquirt wouldn't work on a fiat.

The only problem with megasquirt is that out of the box it's just a lump of clay waiting to be molded. Nothing is point and shoot.

If your sensors and other devices are supportable through tuner studio, you're good to go. If they're not, find other sensors.

My friend was telling me that the easiest way to get going with a crank position sensor is to steal some parts from a 1.9L Escort.

Granted, their cpu is slower than modern factory ECUs come with, but it's also doing less work. And it beats the tar out of what you find in a Jetronic or Digifant ECU.

But it's on you as the tuner to figure out how to make it work.

And yeah, with some machine work you could line up four ITBs on the FI intake mainifold with the plenum removed. I wonder if it would fit under the hood tho?

A guy i know built a monstrous 16v 1.8L rabbit using four mikuni RS carburetors as ITBs. Rusty as heck but really surprised people at the track.


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