Drivetrain Swaps With Rear Upper Crossmember Mods

lookforjoe

lookforjoe

True Classic
Since I want to fit the 'ram' header, I now need to look at examples of conversions where the upper crossmember has been removed/replaced/modified.

I know there have been several, but I didn't bookmark any when they were current & I'm not finding anything in search results.

Can anyone help?

PXL_20210816_203157927.jpg
 
Here's a link to an article where a guy removed the upper crossmember and added x type bracing as a substitute. There was also
a guy selling an X1/9 with a B20 VTEC with a supercharger who removed the upper crossmember as well. I'm not sure what if anything
he used to rebrace that area of the car.

grassrootsmotorsports.com

A Fiat With a Little Secret

This modified Fiat X1/9 is powered by a supercharged Honda K-Series engine and ourperforms the original in all aspects.
grassrootsmotorsports.com grassrootsmotorsports.com
 
I suppose you could look for pics of what Abarth did with the Prototipos. One would think they knew what to do to retain strength under tough rally conditions. Should be lots of pics of that on the web. Example below...dont know if this is a genuine Abarth car or a replica...

abarth.jpg
 
Here is another.......

ebay845713.jpg


Is the plan to retain the trunk? Would it work upside down if the flange was cut off and re-welded? Hard to tell what you're up against without actually seeing it.
 
Dr.Jeff said:
Do you know any details about the drivetrain in this one?
Click to expand...
Yes, it is a 1.4l Abarth (FIRE) engine and a C510 gearbox. The car is built and owned by Jens Hagen, a very nice guy from Norway. He is sometimes racing in Sweden in CAR (Club Alfa Romeo) Challenge series where I've learnt to know him. However, Covid stopped him to attend this and last season. Very quick car, one of the fastest X1/9's in Scandinavia. I haven't seen the car IRL recently, but he rebuilt it with 17" wheels last year. -Not as bad as I first thought it would be:
102762069_248219166597479_8948040431040462848_o.jpg
 
Many thanks for the pics so far
jimmyx said:
Here is another.......

Is the plan to retain the trunk? Would it work upside down if the flange was cut off and re-welded? Hard to tell what you're up against without actually seeing it.
Click to expand...
Yes, I need the trunk, so even if I do a cross tube as with the examples, I will need to build a modified wall. That does throw a spanner in the works in terms of added complexity though.

Won't work upside down - I need the length above the flange. I won't have any pics until I actually remove the existing & cut the crossmember, it's too deep to test fit in any way prior to that.
 
lookforjoe said:
Yes, I need the trunk, so even if I do a cross tube as with the examples, I will need to build a modified wall.
Click to expand...
I think if you use some type of box tubing (square or rectangle) for the main cross brace along the top, then it will be easier to make a new partition/wall for the trunk. Depending on how much room you need, the new wall can even be structural, like a monocoque.

More pics:
X19 seen in Monterey.jpg

Waynes_s_V6engine.jpg

Twin Cam in X19.jpg

295081-1000-0.jpg


Some are just for ideas, not necessarily examples.
 
lookforjoe said:
Since I want to fit the 'ram' header...
Click to expand...
This begs the question, Why?

Do you think it's going to suddenly release 20 extra horsepower? (it almost certainly won't)

A lot of work and effort involved for what may be a very insignificant gain IMO.

all the other examples shown have all had the engine cover and rear boot/trunk lid co-joined and lost the rear boot/trunk space ... you need to retain the original hinge points.

SteveC
 
jimmyx said:
Here is another.......

View attachment 50976

Is the plan to retain the trunk? Would it work upside down if the flange was cut off and re-welded? Hard to tell what you're up against without actually seeing it.
Click to expand...

Jimmy - where are the pics of this build? This isn't the 'breathing life' car.... You should have zero upper range issues with that setup :D
 
fiatfactory said:
This begs the question, Why?

Do you think it's going to suddenly release 20 extra horsepower? (it almost certainly won't)

A lot of work and effort involved for what may be a very insignificant gain IMO.

all the other examples shown have all had the engine cover and rear boot/trunk lid co-joined and lost the rear boot/trunk space ... you need to retain the original hinge points.

SteveC
Click to expand...

The engine needs longer runners in NA form. All the tuner-level K-series Honda guys have commented on the need for a 4-2-1 header with much longer runners for NA (VTEC) breathing in the high cam area - so around 6K rpm -on up. Mine starts to choke & run rich around 7K (the tuner tried a combination of more timing, less fuel, more cam advance, what I have is the best compromise), and so my cam advance is limited. With a longer runner header I will be able to better utilize the power that is not available to me in it's current form. Their suggestions are all to fix the header, or stick a turbo/supercharger on it if a shorty header is the only solution. The car is a blast to drive as it is, I'm just not accessing the available performance in the 6.5-8.5K rpm range.
 
lookforjoe said:
Jimmy - where are the pics of this build? This isn't the 'breathing life' car.... You should have zero upper range issues with that setup :D
Click to expand...
No, the red one is not mine. It's just a photo I stumbled upon during a google search, and I couldn't find any build info.

The "breathing life" car is a '75 with a 1300, but my '74 is a K20 build. I didn't go with anything exotic, but I did build the exhaust with longer and less severe bends, but had to give up the rear trunk to do it.

IMG_3007.jpg


IMG_3047.jpg


Also found this one in Sweden. Allows for longer runners, but probably requires cutting out the rear wall and trunk floor and redoing it in some modified version after getting the exhaust where you want it?
20190424_000527-001.jpg
 
jimmyx said:
No, the red one is not mine. It's just a photo I stumbled upon during a google search, and I couldn't find any build info.

The "breathing life" car is a '75 with a 1300, but my '74 is a K20 build. I didn't go with anything exotic, but I did build the exhaust with longer and less severe bends, but had to give up the rear trunk to do it.

View attachment 51020

View attachment 51021

Also found this one in Sweden. Allows for longer runners, but probably requires cutting out the rear wall and trunk floor and redoing it in some modified version after getting the exhaust where you want it?
View attachment 51022
Click to expand...
Those are some really nice welds on your ‘74. I’m jealous.
 
Rodger said:
Those are some really nice welds on your ‘74. I’m jealous.
Click to expand...
One of the very few things I paid to have done. I could have given it a shot, but I figured that somebody who welds all day for a living was probably a safer bet.
 
jimmyx said:
One of the very few things I paid to have done. I could have given it a shot, but I figured that somebody who welds all day for a living was probably a safer bet.
Click to expand...
"I did build the exhaust with longer and less severe bends"
Is your header completely fabricated or are you referring to the rest of the system?

Nice build. ;)
 
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