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Discussion Starter #1 (Edited)
Even though there a lot of threads showing the progress of people's builds, I personally love reading them. I thought I'd start my own thread showing the details of my own rebuild and tuning of my ´74 GT 1300 Junior.

Firstly I'd like to introduce myself to the board members. I live in Denmark, and I'm 39 years old (still for a few months... ;)). I have ridden motorcycles for the last 16-17 years, and have had a number of fun bikes. The last 6-7 years have all been Ducatis. About 3 years ago I bought a wreck of a '58 Ducati 125 TS from a guy in Holland. I have been working on it on and off, and I'm probably about 95% done with it. It's been like that for the last 1½ years or so, but eventually I'll get there...

Last summer I was surfing the internet, and I by accident I saw a beautiful GTV somewhere, and I was sold. I remembered the car from when I was 18 or 19 years old, and I just loved it back then. I had forgotten all about it, but having seen it again I felt it was time to sell the bike and buy an Alfa instead. One month later the bike was sold, and I had bought a healthy '74 GT 1300 Junior from a private seller in Sweden. The car has the usual rust in the panels and along the wheel arches, but the bottom, roof and engine bay are all rust free.

Before the winter I replaced the brakes, steering components, and built a complete new sports suspension in the car from classicalfa in the UK.

Well, back to the engine..... :)

I pulled the engine out about a month ago with a friend of mine that is helping with the task of rebuilding it. He's a mechanic and using his experience and Jim K's book the aim is to rebuild the engine, and at the same time make it produce some more power.

The specs. so far (to be updated):

- 1400 cc piston and liners from Spruell motorsports.
- Skimmed and ported head
- 3 mm oversize inlet valves
- Modified valves for greater flow
- Larger diameter rounded valve seats
- Modified valve guides
- Custom made Auto Verdi con rods
- lightened flywheel (from 9,56 kg to 8,19 kg)
- alfaholics SS exhaust system
- GTA trumpets w. pipercross filters
- 10548 Cams
- Electric fan
- 123Ignition TUNE

I'll keep updating the thread as I go along with the work, and all comments, tips and tricks are very welcome.
 

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Discussion Starter #2
The first task was pulling the engine out. We took of the carbs and the cylinder head with the engine still in the car, and pulled out the engine and transmission as one unit.

There's a lot of old oil and dirt that needs to be cleaned out of the engine bay before reinstalling the engine.

















 

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Discussion Starter #3
Next up: rebuilding the gearbox.

The gearbox was more or less working fine, but in 2nd and 4th gear there was a strange sound. It sounded like a worn out brake pad rubbing against a brake disc. I couldn't quite locate where the sound came from, so I chose to rebuild the gearbox completely.

The synco's were quite worn, and one of the bearing seems to have been somewhat loose. I locked the bearing outer shells in place in the housing with locktite, and replaced all the syncros.

The gearbox and engine were quite badly covered with oil on the outside, so hopefully both will stop dripping after the rebuild, as we are very carefull on cleaning on all surfaces before reassembly.

First, pulling the gearbox apart:

















Second, a lot of cleaning of all the parts in de-greasing fluid:







Third, inspecting the internals of the gearbox:









Fourth, rebuilding the gearbox after replacing the bearing and the syncros:


















The final result :):

 

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Discussion Starter #4
The next part of the project was cleaning and rebuilding the carbs. Something I had never done before either, but turned out to be easier than I had anticipated.

The first carb taken apart and being cleaned in gasoline:



I bought new 30 mm venturis to replace my 28's, but the surface was horrible (the new one to the left). I had to polish them to get an even surface (sorry, forgot to take pics.)



First carb taken apart, cleaned and ready for reassembly:



The first carb finished, and I'm ready to do the second one. It's clear to see the difference.



Both cleaned, rebuilt and ready to be installed on the intake:

 

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Discussion Starter #5
The next part of the project was the valve cover. I wasn't to keen on the looks of the standard aluminium surface, so I decided to paint it with wrinkle paint.

I am more than happy with the result, even though my wife wasn't to impressed with me when I put it in the oven in our kitchen for the paint to dry out completely... :D

3 layers of paint applied:







After 24 hours of drying I baked the cover in the oven at 100 degrees celcius for one hour, and removed the masking tape. I sanded down the lettering with 220 grit paper, and the result speaks for itself:





 

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Discussion Starter #6
Next thing is porting and rebuilding the head. I have read Jim K.'s book on this topic many times in preparation. One thing is understanding the process, but something else is overcoming the mental challenge of actually grinding away in the middle of the heart of my beautiful Alfa.... :D

Having overcome this, it wasn't as bad as I had feared. I have spent many hours on this head now, so I hope it pays of with some serious horsepower in the end.

The intake ports:




























The exhaust ports:










Making room for bigger cams (just in case...;)):









 

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Nice project, the bodywork in the engine bay area looks OK :) I know you are going to install new pistons and liners, but its always a good idea to hold down the liners with some pieces of tubing and the cylinder head nuts. When you have engine out, its very easy to cleanup the gas pedal linkage and add some new rubber bushings and grommets. It made a big difference on my own car, a better "feeling" in the gas pedal. Also check the brake lines, brake master cylinder and clutch master cylinder. When you rebuild the engine, also renew / rebuild the oil pump, its a very important component, and almost impossible to get out of the engine when its mounted in the car. I look forward to hear more about this project :)
 

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Wow, this is wonderful work, great to see this come together!
 

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Discussion Starter #9
Thanks for the comments and advise guys. It's always apreciated.

It's time for another update. :)

Yesterday I turned in my now ported head to the machine shop, and picked it up again this afternoon. They powerwashed it and glass blasted it before doing any work on it. The main purpose of this was to get the right surface in the inlet channels, and of cause to clean it thoroughly.

They were not happy with the valve seats, so we agreed to replace them with new ones. Their recommendation was rounded seats, since the should give the very best flow properties. They also don't need lapping in, and since it was all done in a machine there is no matching of valves needed with the seats (any valve will work in any seat). The valves were also smothened out on the backside to increase the flow.

Lastly the head was skimmed 0,8 mm. I didn't want to go any further, because the pistons are already 12:1 compression ratio, and I want to make sure I can have the head skimmed once again just in case something goes wrong along the way.

This evening I installed the valves making sure the valve spring installation height was matched on all valves. The deviation between the two furthest apart was 0,80 mm. After shimming the springs the deviation is +/- 0,35 mm.

Next project will be installing the cams and adjusting the valve clearances.





























 

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Looks great, and nice docomentation :) These rounded seats are new to me, but they seems to sit deep in the combustion chamber. Shouldent they stand proud of the combustion chamber surface to give a good flow ? You use 3 mm oversize intake valves, but with standard outside dimension seat. How does that fit together ?
 

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Discussion Starter #11 (Edited)
I've never heard of the rounded seats before either, but thinking about it, it does make sense that the flow should be better. The machine shop have a lot of experience with it, and beleive it or not, they do it a lot for engines used for tractor pulling.. :)

I'm not sure whether the seats are sunk to deep into the combustion chamber. Do you think so, and why?

The outer diameter of the valve seat is still the same, but actually it is 38,8 mm, and the standard valve is only 37 mm. The innner diameter however is about 1 mm larger than stock, and the valve has the contact point much further out than the stock 37 mm valves.

This is what Spruell motorsports write about the valves on their website:

Special made from 214 NEVA STAINLESS STEEL ALLOY.

This 3mm oversize intake valve will breath new life in your 1400cc engine. No need to replace the stock 34mm exhaust valve.

*We tried this combustion on a 1300 two barrell Solex Guilietta Spider and it was never outrun by a dual weber and it was 1300 Alfa. We guess it is worth 2-4 HP. You will never find cheaper bolt on HP. Well worth the money to try this on your next valve job.

*No need to replace the stock intake seat, just allow a .015 margin to overlap the seat.
 

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,,, that 'rope' trick that you used to take the motor tranny out, that looked really scarey...perhapes a chain might be better?
 

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71 Berlina 74 GTV 17 Giulia Q4
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I did pretty much the same with my 2L JimK's book etc and was really happy with the results, so you should be as well.
Why the sander? on the head surface? Been around awhile and never seen that before and did it leave those marks on the head seating surface? Not trying to tell anyone what to do but that would scare the you know what out of me if it was mine.
Thanks for sharing, welcome to the fold!
 

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Discussion Starter #14
The long runder marks on the head is from milling it down. The reason for using the sander is to make sure there are no long liniear marks across the surface as these could potentially act as oil channels. The sanding was very lightly done for a very few seconds. There are still a few marks left visible, but even with a finger nail you cannot feel any edges, so it is very smooth. I'm not worried that it will not seal properly.

I trust the machine shop on their choises. The only do cylinder heads and regrind cams and cranks, so I hope they know what they are doing.

The guy that did the work has been doing nothing else for the last 10-15 years.
 

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Sounds good to me, with the side lighting the marks must look deeper than they are. Let us know how it turns out!
 

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Discussion Starter #16
I am waiting for a new bolt for the cylinder head, so I have put it on hold until the part shows up.

Instead of working on the head I decided to prepare the con rods for shot peening before reinstallation. However I might have screwed it up.... :(

In the effort of matching the weight of them I regrinded one of them a bit in order to remove 2 grams of weight from it. After looking at the result it is obvious that I accidently removed more from one side than the other. I removed 8 grams in total, so I'm not sure whether it would even be a problem, but I hope someone here in the forum can answer that.

The mishap seen from one side:



And seen from the other side:



Some pics of the grinding and polishing in general:















 

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This is what Spruell motorsports write about the valves on their website:

Special made from 214 NEVA STAINLESS STEEL ALLOY.

This 3mm oversize intake valve will breath new life in your 1400cc engine. No need to replace the stock 34mm exhaust valve.

*We tried this combustion on a 1300 two barrell Solex Guilietta Spider and it was never outrun by a dual weber and it was 1300 Alfa. We guess it is worth 2-4 HP. You will never find cheaper bolt on HP. Well worth the money to try this on your next valve job.

*No need to replace the stock intake seat, just allow a .015 margin to overlap the seat.
Nice job, seriously. I expecially appreciate because I know how time consuming and fatigueing is to port an Alfa :)
Just a question: you are using 3 mm bigger inlet valves, but I can't imagine where's the gain in putting a bigger obstacle in front of a same-size orifice...
usually I tend to REDUCE by half millimeter the valve diameter, trying to keep the contact surface as thin and outer as I can... So, interesting job a radiused seat, but why a larger valve?
 

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Discussion Starter #18
It's time for another update. I don't have the guts to use the con rods because of my excessive grinding/polishing, so I have ordered a set of custom made rods from Auto Verdi in Sweden. It will take 5-6 weeks before they are finished, so I am looking very much forward to receiving them.

Today I finished the cylinder head, and have tucked it away before reinstalling it.

Last weekend I modified the flywheel to reduce the weight. The weight was reduced from 9,56 kg to 8,19 kg. The majority of the weight was taken off on the outer part of the flywheel where it has the most effect. This is a reduction of about 15%.

Some pics of the operation:















 

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Discussion Starter #19
Nice job, seriously. I expecially appreciate because I know how time consuming and fatigueing is to port an Alfa :)
Just a question: you are using 3 mm bigger inlet valves, but I can't imagine where's the gain in putting a bigger obstacle in front of a same-size orifice...
usually I tend to REDUCE by half millimeter the valve diameter, trying to keep the contact surface as thin and outer as I can... So, interesting job a radiused seat, but why a larger valve?
My thought exactly. However the inside diameter of the valve seats have been widened as well as the porting of the head. According to Paul Spruell: "We guess it is worth 2-4 HP. You will never find cheaper bolt on HP. Well worth the money to try this on your next valve job"

I am no expert, so I lean towards the experience of a guru like Paul Spruell who has tuned Alfas for many years. The valves needed replacement anyway, so why not use something that increases power... ;)
 
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