128SL Coupé winter project

Bjorn Nilson said:
I've found a dry and warm place for the X1/9 to hibernate and thereby created necessary space in the garage to work with the 1974 128SL during the winter. It will be a full restoration project with minor mods with an Abarth-touch. Today I started fixing the doors that have badly done rust repairs with tons of bondo and bad weldings. I also see rust around the front/rear windows, but in general, the car is not as rusty as expected.
I will probably widen the lower parts of the fenders a little bit (with steel) and remove the bumpers. And I will definitely lower the suspension by 80-100mm as there is way too much space between the wheel and fender lip in my opinion. -I prefer a low ride.
The 1300 engine is running well but it is knocking when warm so I will most likely have my spare 1500 instead, but with the angry EU cam from the 1300. The twin Weber 40 will go for injection and modern ECU management. The 4-speed gearbox will need new synchros on all gears, but I have a Ritmo 5-speed box as well and will probably use that one if not too complicated (space, drive shafts etc).
It is nice that many of my X1/9 spares can be used. There's more to come...
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The 128SL was such a great car, loved driving it as much as my X1/9, point the wheels, put your foot down and go !
Will be watching this restoration closely!
 
Bjorn Nilson said:
I've found a dry and warm place for the X1/9 to hibernate and thereby created necessary space in the garage to work with the 1974 128SL during the winter. It will be a full restoration project with minor mods with an Abarth-touch. Today I started fixing the doors that have badly done rust repairs with tons of bondo and bad weldings. I also see rust around the front/rear windows, but in general, the car is not as rusty as expected.
I will probably widen the lower parts of the fenders a little bit (with steel) and remove the bumpers. And I will definitely lower the suspension by 80-100mm as there is way too much space between the wheel and fender lip in my opinion. -I prefer a low ride.
The 1300 engine is running well but it is knocking when warm so I will most likely have my spare 1500 instead, but with the angry EU cam from the 1300. The twin Weber 40 will go for injection and modern ECU management. The 4-speed gearbox will need new synchros on all gears, but I have a Ritmo 5-speed box as well and will probably use that one if not too complicated (space, drive shafts etc).
It is nice that many of my X1/9 spares can be used. There's more to come...
View attachment 67255
Click to expand...
Would you be willing to sell the twin weber 40 ? If its not for the headprice i would Def be intrested as im looking for one for my project 128 (more info is on my own thread called: green 128 1100 1976 where a 1400 race engine is going in)
 
T.G said:
Would you be willing to sell the twin weber 40 ? If its not for the headprice i would Def be intrested as im looking for one for my project 128 (more info is on my own thread called: green 128 1100 1976 where a 1400 race engine is going in)
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You are not the first one to ask so I'll put you in the line. If you going for a race engine why don't you go for injection like the high revving Gr. 2?
 
Bjorn Nilson said:
You are not the first one to ask so I'll put you in the line. If you going for a race engine why don't you go for injection like the high revving Gr. 2?
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I would like to keep it with carbs there is just something about period correct cars so a car from 1976 needs to have carbs in my opinion and also its a engine from a ex racer (im pulling it out of the racecar) and it has lightend rods and a lightend flywheel and a race cam and bigger pistons and made around 110 hp to the wheels around 15 years ago when it was running so im gonna be taking it compleetly apart and rebuilt with even bigger pistons so im hoping for 120 hp at the wheel but yea i would prefer carbs on it
 
T.G said:
I would like to keep it with carbs there is just something about period correct cars so a car from 1976 needs to have carbs in my opinion and also its a engine from a ex racer (im pulling it out of the racecar) and it has lightend rods and a lightend flywheel and a race cam and bigger pistons and made around 110 hp to the wheels around 15 years ago when it was running so im gonna be taking it compleetly apart and rebuilt with even bigger pistons so im hoping for 120 hp at the wheel but yea i would prefer carbs on it
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I understand and that is ok if you're not going for serious racing. However, if you're planning to race (classic) with a 1400cc the limits in EU is 1300, 1600, 2l... So you'll meet Ford Escorts 1600 etc and to be honest I think they will slaughter you on the track. The 128 is lighter than the X1/9 but the X1/9 is a sooo much more race worthy car and has many of the features that youre not allowed to modify on the 128 if going to race it.
 
Bjorn Nilson said:
I understand and that is ok if you're not going for serious racing. However, if you're planning to race (classic) with a 1400cc the limits in EU is 1300, 1600, 2l... So you'll meet Ford Escorts 1600 etc and to be honest I think they will slaughter you on the track. The 128 is lighter than the X1/9 but the X1/9 is a sooo much more race worthy car and has many of the features that youre not allowed to modify on the 128 if going to race it.
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Nope not gonna race it like that i will probably go on a open trackday sometimes but otherwise just gonna be a streetcar
 
That's not going to be a very fun car on the street... Unless your 'street' driving is all mountain roads and autocross lots... Small displacement, big cam, big carbs, lightened flywheel.... It may make 110-120 hp, but it will have no torque.. You're going to have to rev the piss out of it just to leave a traffic signal... I'm all for 'race car on the street'... It's how I build all my cars, but some compromises need to be made for tractability that will limit top end power.. If you want power and drivability, you have to up the displacement and match it to a cam that comes on lower in the revs... That's why I'm building a 2 litre.... I'm in the process right now of tearing down my Mini engine because when I built it, I was thinking just like you, Max power.. Every choice made the car less drivable in everyday situations though. Cam just a little too hot, 1.5 ratio rockers moved it even further up the rev band, big side draft carbs on a short manifold would bog at low RPM's... Sure it made 120 at the wheels, but like I said no fun to drive to the store, or work... A small, highly tweaked motor is going to have a very narrow powerband high up in the revs, then your going to need an ultra close ratio gearbox to stay in the usable RPMs... I know you're 18, and maybe you think you just won't care, but I'm not some 'old guy' complaining about comfort.. All my cars have spherical jointed suspensions and soft race compound tires that transmit all road noise and feedback into the car, and don't last very long... So I'm not talking about practical, or comfortable I'm taking about drivability... I don't think driving a race engined car around town is going to be what you think it is... Just my 2¢....
 
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Lowtechprime said:
That's not going to be a very fun car on the street... Unless your 'street' driving is all mountain roads and autocross lots... Small displacement, big cam, big carbs, lightened flywheel.... It may make 110-120 hp, but it will have no torque.. You're going to have to rev the piss out of it just to leave a traffic signal... I'm all for 'race car on the street'... It's how I build all my cars, but some compromises need to be made for tractability that will limit top end power.. If you want power and drivability, you have to up the displacement and match it to a cam that comes on lower in the revs... That's why I'm building a 2 litre.... Just my 2¢....
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100% spot on! Sooo many people just don't understand the trade offs and unfortunately they tend to go with a "more is better" approach. And this seems even more prevalent with Italian car owners. As you said, it depends on the use of the vehicle - race or street. Frankly you cannot have both.
 
T.G said:
Nope not gonna race it like that i will probably go on a open trackday sometimes but otherwise just gonna be a streetcar
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That's what I do with my X1/9 but it is so much more fun with the 240hp UT engine than with the 100hp 1500 engine. It also doesn't fit in any class so I don't race it. It has lots of torque over the whole powerband so it is drivable also on the street. With modern ECU, injection etc it has become a very reliable car, and it starts easily in all conditions but is still a classic.
The 128 will be a daily driver so I will modernize that one too so the Webers will have to go.
 
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Bjorn Nilson said:
That's what I do with my X1/9 but it is so much more fun with the 240hp UT engine than with the 100hp 1500 engine. It also doesn't fit in any class so I don't race it. It has lots of torque over the whole powerband so it is drivable also on the street. With modern ECU, injection etc it has become a very reliable car, and it starts easily in all conditions but is still a classic.
The 128 will be a daily driver so I will modernize that one too so the Webers will have to go.
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I can certainly understand the advantages of a modern F.I. system, but I have to side with T.G. on that one! I'm still a big fan of carburetors, (no computers in my cars thank you!) although lately I've been favoring bike carbs... You build it how you like though right? (T.G. too) Everyone's taste is different! 😁
 
Lowtechprime said:
That's not going to be a very fun car on the street... Unless your 'street' driving is all mountain roads and autocross lots... Small displacement, big cam, big carbs, lightened flywheel.... It may make 110-120 hp, but it will have no torque.. You're going to have to rev the piss out of it just to leave a traffic signal... I'm all for 'race car on the street'... It's how I build all my cars, but some compromises need to be made for tractability that will limit top end power.. If you want power and drivability, you have to up the displacement and match it to a cam that comes on lower in the revs... That's why I'm building a 2 litre.... I'm in the process right now of tearing down my Mini engine because when I built it, I was thinking just like you, Max power.. Every choice made the car less drivable in everyday situations though. Cam just a little too hot, 1.5 ratio rockers moved it even further up the rev band, big side draft carbs on a short manifold would bog at low RPM's... Sure it made 120 at the wheels, but like I said no fun to drive to the store, or work... A small, highly tweaked motor is going to have a very narrow powerband high up in the revs, then your going to need an ultra close ratio gearbox to stay in the usable RPMs... I know you're 18, and maybe you think you just won't care, but I'm not some 'old guy' complaining about comfort.. All my cars have spherical jointed suspensions and soft race compound tires that transmit all road noise and feedback into the car, and don't last very long... So I'm not talking about practical, or comfortable I'm taking about drivability... I don't think driving a race engined car around town is going to be what you think it is... Just my 2¢....
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Very spot on yes but here the roads are long en real flat and yes we have alot of fun roads here (even tho its al completly flat) so im probably gonna build it like i was planning on and then i will see if its any good for some daily driving or not (if not im not sad about it i have a alfa with 180 hp and 410nm to the wheels so yeah and probably gonna be picking up a merc 190e soon for daily driving/drifting) and as you said if its way to impractical the il search for a bigger displacement engine
 
Lowtechprime said:
I can certainly understand the advantages of a modern F.I. system, but I have to side with T.G. on that one! I'm still a big fan of carburetors, (no computers in my cars thank you!) although lately I've been favoring bike carbs... You build it how you like though right? (T.G. too) Everyone's taste is different! 😁
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Im not not a fan of computers in my cars (as i have a 2011 alfa) if the work good and reliable if not its going straight out the door
But just like i said its just something about cars like these being period correct if you get me
 
Bjorn Nilson said:
You are not the first one to ask so I'll put you in the line. If you going for a race engine why don't you go for injection like the high revving Gr. 2?
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Isn't that kinda weird to have the injectors out on the ends of the air horns before the slide throttle openings like that? What happens at part throttle? Do you just have fuel hitting a closed throttle plate??
 
Lowtechprime said:
Isn't that kinda weird to have the injectors out on the ends of the air horns before the slide throttle openings like that? What happens at part throttle? Do you just have fuel hitting a closed throttle plate??
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I thought so too, but then I realized that the ECU will mix it correctly when properly tuned. No air, no fuel?
 
Most injection systems with injectors located like that (outboard of the airhorns) are mechanical injection on race-only engines....nothing but WOT all the time. Many even use "slide" valves rather than "butterflies" for the same reason. They aren't concerned with drivability or smoothness, so long as they achieve maximum output at WOT. ;)
 
I see your point about WOT, and that engine does have a slide 'guillotine' style throttle, but what is the advantage/benefit of having the injectors out there instead of in the manifold after the throttle plate?
 
Lowtechprime said:
I see your point about WOT, and that engine does have a slide 'guillotine' style throttle, but what is the advantage/benefit of having the injectors out there instead of in the manifold after the throttle plate?
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I believe better distribution, more complete atomisation of fuel. Perhaps also less airflow restriction.
 
It may also be to create a cooler mixture since the fuel has more time to expand than a port injector near the intake valve.
 
Lowtechprime said:
Where are you Bjorn on the Winter project? Any progress on the Coupe'?
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The project has slowed down as the X1/9 required some attention; preparations for the summer and MOT. I am also enjoying Berta by going to car enthusiast meetings, trackdays and slalom racing so I currently spend more time driving my X and less time in the garage.
Basically all rust repairs are done on the 128, The rockers are welded on and templates been made for the fender flares.
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