Budget 2.0 (2L) build

[maytag]

I beat Zmatt to it!

In a related thread, fiatfactory suggested that zmatt start a thread to this topic.... and I loved the Idea so much that I thought I'd chime-in too.
I am also in the process of building a budget 2L. I'd be further along in this build, if not for the fact that I bought a '79 2L for my donor car, only to discover that it's a transplanted 1800....

ANYWAY:
Here's my intended build. Any suggestions from others who've been down this road are welcome. (I'm easily distracted, so please try not to distract me over trivialities that are matters of preference, as opposed to actually better parts or more effective components. )
The goal is a fun, reliable street motor. I'd like it to rev to the moon, and make all the right noises. And I have always been willing to sacrifice a little "streetability" for more of anything that makes me go

1) We'll start with the 2L bottom end. I've got my eye on one I may have within the month. I'll check it over, but I'm hoping to not have to do any extensive machine work. Stock crank. Stock rods. I don't know if these blocks benefit from deburring, or if oil holes should be chamfered, or?? I've not yet had one of these open. But my usual method is to clean everything up really well that way. I'll also match-balance the rod /piston assembly as closely as possible. If I understand correctly, these motors being 180d cranks don;t need for me to balance a bob-weight to the reciprocating assembly, right
? So can I lighten-up the crank at all?

2) Pistons: I'm debating just sticking with the stock pistons (assuming they mic out okay). With an 1800 head, that should net me around 9.5:1 compression ratio, right? Would I benefit from new pistons and going a little higher? I don't want to spend a bunch of my budget on extreme ignition components, so I don't want to get too crazy with compression.

3) Head: I have several 1800 castings on the shelf to choose from. Are there any that are better / more desirable than others? If I go with new pistons (see above) is there any benefit to keeping the 2L head? I'll port-match the head & manifolds, but probably not do too much more to the ports, unless y'all have seen good results from a home-grown port-job (I don't have a flow-bench, but I understand the theories and dynamics). Should I be polishing the runners? What about the chambers? polished? Of course I'll get a good valve-job done, but should I stick with the stock size valves? Or go bigger?

4) Cams: I got a great deal on a set of new IAP autocross cams, so I bought 'em. I should think they'd work well with what I'm putting together here? I'll mate 'em to some adjustable cam gears, so I can time 'em correctly.

5) Intake: I picked-up a waffle manifold and some 40idf's. I should think 40's should accommodate this level of build? unless my altitude (4000') makes 'em too small?

6) header: I can't decide. I LOVE the look of Mark's header. But that's a chunk of the budget. there are less expensive options, including the 4/2/1 that's on my shelf. Any experience on ability to breathe with either Mark's or Vick's headers, as compared to the 4/2/1 ?

7) Ignition: I'm thinking just stick with the electronic ignition from the donor car, with a good solid coil. ????



any tips, hints, suggestions?
thanks in advance!

[BEEK]

the 2.0 bottom end is pretty bulletproof, except for aux shaft timing and oil pump pickup damage.
my personal recommendation is.

1. clean block, deburing the inside will help, cant go wrong if you do it yourself. oil control will gain or loose you as much as 20hp. that is in a race engine, but oil on the crankshaft in a street engine driven hard will do the same.

2. 9.8-1 compression is great for the street, can run on premium fuel. i would recommend total seal 2nd rings.
i would also deck the block to 0, with the pistons at tdc. doesn't cost that much, and you will have a great new gasket surface.

3. head, i would not recommend porting a head if you have no idea regarding the principals of porting, for bigger is not always better. smooth is not always better. but that being said, a ported head will gain you some power, but if you are not going to be running 6-7k rpm all day probably not worth it. if you have a efi 2.0 head i would probably use that with the 9.8 -1 pistons, the combustion chamber shape is better and the intake is un-shrouded a bit more.

4. big valves, again no gain unless you do a porting job, enlarge the seats of replace them. and yes you can open up the original seats to accommodate big valves, I've done it with success. just cant be stupid and grind them too thin.

5. camshafts, the bigger cams will help, i would recommend you use the big intake cam, leave the stock exhaust cam. get a set of adjustable cam pulleys, and set your timing.

6. 40 idf's on a waffle manifold will be perfect for your application. you will have to play with the jetting a little. the stock ports are a bit small on that manifold, again opening them up wont hurt, but make sure that the manifolds ports are smaller than the heads ports or match them exactly.

7. ignition, the marelli electronic distributor will work perfectly. i would get a better module which allows better saturation of the coil, and a better coil. set the timing at 32deg maximum advance, where i would start at max advance at 3500/4000 rpm
where it falls to after that isn't a real problem, the initial start up advance may be a bit high usually 15 or so. just have to play with that , unless you go aftermarket or edis.

8 exhaust. ive never had one of marks headers, but from what i understand he has the proper runner length for this motor. a ansa type 4-2-1 works better than a 4-1 stock manifold. depends on what you have and your budget. i would recommend a 2 1/2 exhaust system from the union where the 2 goes to 1 on the header , all the way to the back.

i would spend the money on a aluminum crank pulley and flywheel. its money well spent, imho

this is just my opinion, everyone who responds to this is going to have different ideas, none being more right or wrong. just different. keeping in mind what you have at your disposal, and a budget in mind. thats what i would build if it was mine.

[TulsaSpider]

Great info! I am building the same thing!

[maytag]

Wow! Great info & opinion! Exactly what I was looking for!

1. oil control will gain or loose you as much as 20hp.

Have you (or others) ever used a crank scraper in these motors? I assume there is some sort of windage-tray in the pan?

2. 9.8-1 compression is great for the street, can run on premium fuel. ....i would also deck the block to 0, with the pistons at tdc.

is 9.8~ what I get with original pistons, an 1800 head and the block decked to 0 like you've suggested? OR are you suggesting new pistons?

3. i would not recommend porting a head if you have no idea regarding the principals of porting,

I've ported several heads before, ranging from big Buick motors to 1 2-valve Ducati head and some 5-valve Yamaha heads. I've had some really great results... and I've had a couple dogs I had to tear-off and throw away. I understand the principles, but some motors are so sensitive to pulses and feedback. I've found that if I can 'copy' someone smarter than me, I'm competent with the tools. But left to my own devices.. I probably shouldn't.

5. camshafts, the bigger cams will help, i would recommend you use the big intake cam, leave the stock exhaust cam. get a set of adjustable cam pulleys, and set your timing.

Does this still apply if the head is ported, allowing the motor to breathe a little more on the exhaust side? And for cam timing: is this going to be a guesstimate for me? or is there a tried-& true degree / number that is the standard, and it works?

the stock ports are a bit small on that manifold, again opening them up wont hurt, but make sure that the manifolds ports are smaller than the heads ports or match them exactly.

won't that kill my velocity? Will we gain volume? or is this an issue of pulse-waves again? if I create a smooth, linear "horn" shape as it works towards the port, is that ideal?

...i would get a better (ignition) module ....

With all the parts I've shopped and looked at, I don't think I've seen (or even heard about) an improved module. Is this to be had from an aftermarket source for the Fiat? Or are y'all part of some super-secret-society that knows some easily obtained pontiac part works in its' stead?

i would spend the money on a aluminum crank pulley and flywheel.

agreed. 100%. but this brings me to the balancing issue I mentioned above. Is balancing (or even matching the bob-weights to each other) even worth it at this level of build?

[fiatfactory]

.

[maytag]

2) Pistons: I'm debating just sticking with the stock pistons (assuming they mic out okay). With an 1800 head, that should net me around 9.5:1 compression ratio, right? Would I benefit from new pistons and going a little higher? I don't want to spend a bunch of my budget on extreme ignition components, so I don't want to get too crazy with compression.

Not a chance you will get to 9.5:1 with stock US spec 2litre pistons ... stock US spec is around 8.0:1. The pistons have huge flycuts and sit down the bore some due to a short CH. Euro spec pistons for the 2litre have far smaller flycuts and a taller CH, and they just make 9.35:1 and are still a flat top...that's what a Ritmo130TC has, the 122hp Argenta EFI and the Aust spec 131 superbrava @ 113hp all use the same piston. It's not all about dome height, remember the CH and flycut depth change the static CR just as much. I'll dig out a few pictures for Zmatt and yourself to explain.

So what is everyone talking about then? I seem to recall all over the forums that people are talking about 9.5:1 - 9.8:1 CR when using an 1800 head on a stock 2L? I must be confusing something else?

4) Cams: I got a great deal on a set of new IAP autocross cams, so I bought 'em.

"Autocross" cams can mean absolutely anything, just like stage 2 or stage 5... a totally useless description when applied to a camshaft. You need to accurately determine what you have, total lift, running duration, duration at 50thou, lift at TDC etc etc... even better would be to determine lift per degree of rotation and plot a curve to show what you have which is how any seriuos engine builder would approach this.

I stated "IAP Autocross" 'cuz they seem to be fairly universally known.... but they're a 40-80, 80-40 cam. 248 deg duration @ .050", .35mm lift.
What do you think?

Stock OEM twin IDF manifold is adequate, 40IDF's though are on the small side to get lots of revs, especially with the small 32 chokes and stock aux venturis. There's no point fitting bigger chokes unless modifications are made to the aux venturi as this is actually where the smallest cross section in the carb is. 44's would be a much better choice as this is what Fiat installed on thier performance 1800 in the 124CSA, 40's were fitted to the 1608 engine. Unfortunately 44's on the 40 manifold is another mismatch... and require a bit of work to achieve a good result... it's not just a matter of enlarging the hole a bit so the butterfly doesn't clash. The 124CSA actually ran a very different manifold with larger ports all the way thru... you can't just enlarge the 40 manifold to this size or you break thru to fresh air on the SSR of the first turn. Altitude compensation can be made with the final jetting.

So if the 'waffle' can't be made to work with the 44's, but the 40's are too small... what's the solution? CAN I modify the aux venturis in the 40's enough to handle the larger chokes?

Is it a mechanical advance only distributor? That's another of the small differences between "Euro spec" and what you have as std equip in the US, the advance curve is different and the rest of the world get mechanical only advance.

No, mine has a vacuum advance on it. Is that good or bad? (the advance unit is actually NEW, so yes, it is pulling correctly. I understand most of them fail....)

What about oil-pump?

[fiatfactory]

.

[So Cal Mark]

I'm going to "slightly" disagree with you about reground cams. Guy Croft recently posted in another thread, discounting all regrinds as crap and I'll disagree with him about this also. I agree with a high-lift, long duration grind that a regrind could end up with ramp speeds that aren't ideal. But for a mild-street grind the base circle isn't reduced enough to be a problem. Even a billet cam is limited to lift since the cam has to slide through the bearing journals and after a certain lift, the base circle has to be reduced on those also to get the desired profile. If you factor in the cost of a pair of billet cams at over $800 compared to regrinds at $300, it's hard to justify the extra cost for a street motor, especially a budget build. We've got tons of cars running our street perf cams and the owners love them.
For a race motor, I agree that the billet is a better choice

[fiatfactory]

.

[So Cal Mark]

I'll agree with your statements, but many of them can also be attributed to billet cams. Again, the more radical the cam grind the wider the disparity between regrinds and billets

[guycroft]

"The 40 IDF manifold needs to be welded on the outside of the first bend SSR"

NO IT DOESN'T

GC

[mdrburchette]

I stated "IAP Autocross" 'cuz they seem to be fairly universally known.... but they're a 40-80, 80-40 cam. 248 deg duration @ .050", .35mm lift.
What do you think?

Actually, the IAP Autocross cams are 42/82 and are billet cams that are computer ground from blanks. Here are the specs:
42-82 82-42 valve timing
110° lobe centers
.014" inlet and exhaust valve clearance
304° duration
260° duration at .050 clearance
84° overlap
10.60mm lift

These cams like to rev and don't come in until around 4k rpms. I've got them in my 1608 street motor with dual idfs. I would suggest going with Guy Croft's performance valve springs if you are planning to drive this car at higher rpms.
As far as higher compression, if you're using stock domed pistons, why don't you deck the block?

[maytag]

Actually, the IAP Autocross cams are 42/82 and are billet cams that are computer ground from blanks. Here are the specs:
42-82 82-42 valve timing
110° lobe centers
.014" inlet and exhaust valve clearance
304° duration
260° duration at .050 clearance
84° overlap
10.60mm lift

These cams like to rev and don't come in until around 4k rpms. I've got them in my 1608 street motor with dual idfs. I would suggest going with Guy Croft's performance valve springs if you are planning to drive this car at higher rpms.
As far as higher compression, if you're using stock domed pistons, why don't you deck the block?

I thought this was their "performance" cam? But I trust you mdrburchette... you've never failed me yet!
And I LOVE to drive at the higher rpms, so I'm glad to hear this about the cams, and I'll take your suggestions on the springs.
But now I'm, even more concerned about the 40's? Are they gonna be big enough?


And GuyCroft: thanks for chiming-in! Tell me more about "no it doesn't"!

[mdrburchette]

Look on their website at the specifications and note the Autocross cams are the more aggressive ones.
I think the 40's will be fine. The racers use the 40's with even smaller chokes than what was original equipment. You've got so many things you can change to make those IDFs right for your setup. That's one of the great things about them...and one of the worst...once you get them tuned and balanced, you can start experimenting with bigger jets. I kinda think the 44 are going to be too big, but I've never run them so I don't know.

[maytag]

well, I'm one step further along.....
I just bought my 2L!
Pics and details soon.