engine angle

martijn

martijn

X addicted
Does anyone knows if there are differences between engine mounting between 1500 cc en 1300 cc engines.

As marked in my other posts about the dual webers my engine is tilted backwards. I don't believe it's the manifold but the engine itself.

I have a 1500 cc strada engine in a 1300 body. I used a 4 speed gearbox, which is converted to 5 speed by using a strada gearbox. I used al the 1300 engine mounts and crossmember.

I tried to get a longer 1500 dogbone to fit but it won't. I compared a 1300 and 1500 crossmember but noticed no differences in engine mounting. Maybe the problem is the 4 speed gearbox with the 1500 engine.

any suggestions/opinoions?
 
Cam belt end mount is the same item for 1300/1500, lower engine mount interchanges, cross member is the same... the only real difference is the length of the top engine stay bar (dogbone) to account for the difference in block height between the 1300/1500....

When you tried to fit the longer dogbone the engine tilt wasn't being restricted by the exhaust sytem was it?

You haven't gone and used the upper engine bracket (the one that mounts to the two studs on the cambox) from the strada have you? I have this vauge recollection that these are slightly different to the X19.... but don't hold me to this...

check Matt's website, I'm pretty sure he lists the actual lengths of the two upper stay bar types, that might give you a clue to where the problem is...

short of that being right you can check the included angle of the inlet manifold... between it's head mounting face and the carby mount face... but that's a whole lot easier with it not fitted to the engine...

SteveC
 
I had the same exact problem --

Being from Tennessee, it took me 2 weeks to figure out I had the dog bone mount on the engine upside down.
 
turns out that the manifold is for a 128 fiat afterall, that's why the angle of the carbs is wrong.
 
Welp... it can be fixed!

1. Make or have made wedge-shaped adapters.

2. Have the manifold base milled for the proper angle.

3. Sell it and buy another.

Good luck with your decision.
 
Black-Tooth said:
1. Make or have made wedge-shaped adapters.

2. Have the manifold base milled for the proper angle.

3. Sell it and buy another.
Click to expand...

1. doesn't work... the studs need to come thru the carby stud holes square to the base, or the nut only contacts to one side, not evenly across it's lower flat.

2. Will work, but the stud holes need to be filled with weld...which means opening them up some, to get the TIG tip in there, and then redrilling and tapping them square to the newly milled carby mounting face.

3. will work too, but X19 manifolds are a lot more scarce than 128/ritmo/uno etc etc manifolds, as the X19 angle is unique to just the X19...so a replacement manifold might be hard to find.

I usually go with 2...

SteveC
 
Research I did in '02...

From N54 archives...
"The X1/9 engine sits at 11 degrees forward tilt.
Stock manifold has an included angle of 101 degrees
between the carb mounting and the head mounting surfaces.
This places the carb mounting surface at 90 degrees from vertical (ie. horizontal).
(101 degrees minus 11 degrees=90 degrees)

The 128 engine sits at 23 degrees of forward tilt.
Stock manifold has included angle of 113 degrees.
Which also results in carb mount of 90 degrees from vertical.
(113 degrees minus 23 degrees=90 degrees)

The "universal" intake sold by PBS,
and in common use on many SOHC Fiats has an included angle of 106 degrees.
When used on an X, the carbs angle back at 5 degrees.
When used on a 128, the carbs angle forward at 7 degrees.

Weber (in Pat Braden's book) states that up to 7 degrees from horizontal
is within design limits of the DCNF.
My guess is that PBS gave a couple extra degrees to the X installation,
figuring more of the manifolds would be used on Xs than on 128s in the US market."

The engine angle figures are from Fiat manuals.
The manifold angle figures are from my measurements.

Therefore, a 128-angled manifold used on an X
would cause carbs to lean backward 12 degrees.
Or cause your engine to appear to lean backward!

Interesting to hear 128-angle manifolds are more common outside USA.
Most manifolds I see in USA are the universal fit PBS type.
I think Mayuko Saul is running a PBS manifold on her 128.
If you can't find an X1/9-specific manifold,
perhaps you two could swap.
Then your carbs would sit 5 degrees backward (instead of 12),
and Mayuko's carbs would sit straight up.

I believe it was SteveC who shipped a 128-angle manifold to Oregon many years ago.
Notice carbs sit level instead of leaning forward
as they do when PBS manifold is used on 128.
Pictured below...
1287.jpg
 
Factory manual shows engine bracket on the body tilted at 9 degrees 30 minutes for an X19, and 18 degrees 30 minutes for a 128...

http://www.turbo124.com/forum/viewtopic.php?f=10&t=6047

I've seen it quoted at 11 degrees x19 and 20 degrees 128/ritmo, so 9 degrees tilt difference....

Yes, I did sell the previous owner that manifold, he wanted to get the carbs level, not liking the tilt with the "split the difference" PBS manifold, which I also believe is less than ideal.

SteveC
 
Truly amazing...

...3 different spec sets for engine angles.
Still, the effect of manifolds on carb angles remains the same.
Yes, PBS manifold is less than ideal.
Just tossin' out a backup option.
 
option 4: lower front of the car ;)

When everything works out with the 40'ers, I will take over the old manifold for my 1300.
I will go for option 2 and get it level for the x1/9.
It seems most of the newly offered manifolds are all 20 degrees and marketed as X1/9 and 128 suitable.
 
I was wondering is it maybe an option to cut it just under the flange.
Change the angle on the manifold and weld the flange back on.
This would save some work, but perhaps make it less accurate.
 
I think what is being confused is the engine is tilted 9.5 degrees from vertical but the face on the head where the manifold mounts is 11 degrees from vertical. Hope this helps in providing some clarity.
 
Last edited:
carb spacers?

I've only had FI cars so you guys will have to humor me on this...

why couldn't you just make wedge shaped adapter plates that fit between the carb and manifold? It seems to me like the angle of the carb mounting studs would be easier to modify than the ones for the head. You could maybe even use one like the wheel adapters where you bolt the spacer to the manifold (with flush bolts) and the carbs to the spacer. Now that I've typed that out... maybe it is just as much work for a less than ideal solution. Especially considering likely hood clearance problems...

Next idea...Are the flanges of the manifold thick enough to mill at an angle? Seems like it might be easier to mill/ re-stud the carb mounts than the head surface if it was thick enough...

someone school me!
 
For an FI guy... you make a lot of sense...

I haven't had that much experience with ill fitting manifolds on Fiats and like I said earlier, the ones I've seen had the flanges milled that mounted to the head.

But with all the V8's I've messed with... including having observed a Cadillac intake milled a bit to fit an old Studebaker... all your suggestions have been done successfully at one time or another!
 
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