2.0 vs 1800 question

[MrJD]

I found the original reference i was thinking about when I made this post. They actually mention that the 1600 head is a more performance oriented piece. That doesn't make much sense to me... Any of you see any truth in such things?

I also have been told the later 16 valve heads can potentially be used.. but require ENTIRELY more work than they are worth.

Also, I'm not sure I would go for FI, as you would lose some of the "song" we were discussing earlier while adding in more wiring... not to mention the difficulties involved in appropriately tuning a FI system to match significant performance mods (i guess you could go megasquirt... but for the same money you could just do a dual carb set up... get the same power... AND have the song to go with it). You'd lose mpg... but we're not shooting for economy now are we?

[djape1977]

in europe
1608cc was 90 or 100hp, depending on version
1585cc was 100 to 105hp
1756cc was 107- 111hp
2 litre was 112

and i'm talking only about single carburetor versions. there were also dual carbs and EFI versions. this would imply that there was more HP per litre out of 1585cc than in 1995cc. it had big dome pistons and larger valves. combined with smaller combustion chamber, this makes head out of 1585 more "performance oriented" than one on 2l.

[narfire]

My two-bits.... what kind of budget are you thinking of? Lots of options for $500-$5000.00.
These cars are good with stock power, the FI anyway, but a little more is always nice... Handling improvements are a good option as well..
Chris

[ga.spyder]

It gets to the point of do you want to spend thousands to gain 25 h.p.? How much are you willing to spend to gain 10hp.All things are possible with an unlimited budget.What is it you are trying to gain? I think it something we have all had to ask ourselves,at one time or another.

[BEEK]

as someone already said, torque, not hp is what you are looking for. compression is the biggest bang for the buck, then a 1800 intake and a larger carb. then a better flowing exhaust, with that you should be happy, after this you will spend alot for a little

[RRoller123]

Would you recommend this for an FI too? I was thinking that a better air filter, lighter flywheel would be a good start. Then raise the CR? Not interested whatsoever in top speed, just being more zippy between 20 and 60 around the back roads.

[MrJD]

It gets to the point of do you want to spend thousands to gain 25 h.p.? How much are you willing to spend to gain 10hp.All things are possible with an unlimited budget.What is it you are trying to gain? I think it something we have all had to ask ourselves,at one time or another.

I see this as less of an issue on a carb based engine. Let me put it to you this way: on one of my previous toyotas, I had $500 in a sensor and relay system just to tell me the air/fuel mix on the engine.. add another 300 for a piggyback A/F management system and various required accessories... you're looking at a grand just to DEAL WITH the FI system... not to mention how much it costs to upgrade fuel pumps and injectors... and how tough it can be to tune a system in this manner.

I just want the car to be peppy, and I want to know where I'd stand with it. The one I am going to look at this weekend has a decent looking header and a full exhaust system on an 1800. I'm not sure what brand of header, the current owner called it a "Vas" which is new to me


Frankly, If I buy it i will change the cams and carb and call it a day (provided the compression is ok). It also comes with a blown 1800 engine... but I thought i'd put my hands on a 2.0 to build up in my spare time. I tend to find huge costs less of a burden if you spread them way out. That being said, if I built an engine I would want to start out with the very best parts... and if one head is a better starting point than another, I'd do all in my power to utilize it.

[narfire]

Let us know how you make out if you purchase. No shortage of opinions here
Upgrade the stock carb to the 32/36 or a 34 ADF (expensive) or if you can find one, 34 DMSA that is not worn out.
In my experience with upgraded cams on my FI is that I also installed a set of adjustable cam wheels and then degree'd the engine/cams properly. The degreeing made a big difference in the power compared to just adding cams.
Good luck eh..

[BEEK]

vas, most likely means it comes from vicks auto sports , a fiat parts vendor

[ga.spyder]

Here is that header
http://www.vickauto.com/newstore/index. ... ts_id=2967

[MrJD]

Who knows if I will buy it... it has more body rust than makes me comfortable... but I am a pretty decent metal worker (and I have auto body experience) so no major issue there. The only thing that worries me is that if the body has rust... what of the suspension connection points... and steering rack connections, etc? I'll know when i see the car I suppose. If they're rotten I'm walking away. He told me it comes with a pile of parts including several carbs the he "has no idea" what they are. Maybe I'll luck out and get something worth while.

In the end though, I have to have a dual weber setup... I've been wanting something like this for at least the last ten years.

I built the system below when I was about 18 years old for a toyota... wrecked the car before they got put on (girlfriend {now wife}'s fault). Would have been a sweet set up. (they weren't done, so ignore the clamps and such rather than welding.)





Header: Thanks for the info! Those are pretty long tubes, be great for a high winding engine.

[ga.spyder]

Here is a older but excellent buyers guide to the Fiat Spider.Crossmember and shock tower rust can be deal breakers.This guide has everything you need to look for.Good luck!!
ps...the Toyota setup looks awesome
http://www.mirafiori.com/faq/content/buyspid.html

[timinator]

as someone already said, torque, not hp is what you are looking for. compression is the biggest bang for the buck,

Just wanted to add to the conversation. Torque is work. HP is the rate at which work is done and is a function of rpm. Work done limited to low rpm does not produce much HP, and therefore slow rates of acceleration. So HP is what we are looking for if exciting driving is the goal.

Small engines are subject to one constant problem in that they only produce so much torque. The only ways to increase their performance is to increase rpm or add more fuel and oxygen to the exsisting system.

Chemical supercharging is the best bang for the buck. It can be installed without parts changes to the engine. Learning how much increased power the engine can withstand can be expensive though.

Compression changes are used in conjunction with other engine modifications to maintain driveability. 1 point of compression by itself only accounts for a 3-5% increase in efficiency provided that the engine does not go into detonation.

Not interested whatsoever in top speed, just being more zippy between 20 and 60 around the back roads.

You can hook up the activation of nitrous oxide to throttle position and install multiple stages.

This type of modification may not be what Fiat purists will tolerate but the system can be easiiy disguised. And no I don't sell these systems but I have installed some for customers.

[vandor]

>Here is that header
...

IAP sells these headers too. I used to sell them in my previous job and they are notorious for leaking where the upper and lower halves connect. It's pretty much a guarantee - just wait a few years and they will leak, making that annoying exhaust-leak sound. The two parts can sort-of be welded together, but then you can't take the header out of the car unless you take the engine out!
A friend of mine bought a set from IAP a few months ago, and they would not fit. He had to send them back, turns out there was a batch that was made wrong.

[focodave]

as someone already said, torque, not hp is what you are looking for. compression is the biggest bang for the buck,

Just wanted to add to the conversation. Torque is work. HP is the rate at which work is done and is a function of rpm. Work done limited to low rpm does not produce much HP, and therefore slow rates of acceleration. So HP is what we are looking for if exciting driving is the goal.

Small engines are subject to one constant problem in that they only produce so much torque. The only ways to increase their performance is to increase rpm or add more fuel and oxygen to the exsisting system.

Chemical supercharging is the best bang for the buck. It can be installed without parts changes to the engine. Learning how much increased power the engine can withstand can be expensive though.

Compression changes are used in conjunction with other engine modifications to maintain driveability. 1 point of compression by itself only accounts for a 3-5% increase in efficiency provided that the engine does not go into detonation.

Not interested whatsoever in top speed, just being more zippy between 20 and 60 around the back roads.

You can hook up the activation of nitrous oxide to throttle position and install multiple stages.

This type of modification may not be what Fiat purists will tolerate but the system can be easiiy disguised. And no I don't sell these systems but I have installed some for customers.

Horsepower = (Torque X RPM) divided by 5252.
If you are continuously running your engine at more than 5252 RPM, then you might have a point that you want to design your engine to produce max HP rather than concentrating on making more torque.
But up to the magic 5252 RPM point, the more torque you make, the more HP you will achieve.
HP and Torque curves intersect at 5252 RPM.
I would submit that most Fiat Spiders are run at 5252 RPM or lower most of the time, and therefore; if you concentrate on making more torque, HP will come naturally per the engineering equation stated above.
I would also suggest that if you simply try to make a twin-cam Fiat make horsepower instead of concentrating on making more torque, you will be sorely disappointed at the end of the day -- particularly in the sub 5252 RPM range.