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Now we can see if this Ferrari engine actually fits in this tiny little Alfa 105's engine bay.]
A couple of layman thoughts:

1. Could the intake runners be radiused 90º so that the red plenums were rotated down and sit down above the heads? You'd keep the F-car plenums, the intake runner length would remain the same, the throttles could be at the front as you said, and it may clear a stock hood (bonnet?).... hmm. You'd have to take them off to get to the plugs, yes.

2. Even though I understand those blue steel tubes boxed-in are quite strong, I feel like the thin-ness of the center of that new "beam" essentially puts a structural "hinge" in the shell of this car. That's how we would describe a strong structure in one portion of a building or bridge, and a strong portion in another, but the joint between them is not near as stiff and the whole thing will tend to "hinge" right there.

You don't have the space to increase the depth of that member UP obviously. What's the situation beneath this cross member? Is that the lowest portion of a 105? The pan sits lower by a bit, then some of us hang the steel strap pan guard even lower. Could you reinforce this crossmember beam with more depth down, below the current bottom edge? You could fab an aluminum skid plate that would divert an impact away from your new pan and the cross member. The BMW E30 guys have some nice ones that are bolt-on.

Even a radiused or bowed steel shape that ties solidly into the uprights at each end. It's not like a bridge where it need strength in the middle - it's a link that wants to bend or flex at each end joint (or the center if not stiff enough).

Just ideas for discussion!
Thanks.
 

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I was very interested to see your solution for this. I have a project in mind that needs some relief from that cross member. My thoughts were more towards cutting out the crossmember in total (leaving the upper a-arm mount) plating it with properly spec'd steel and then creating a removal tube-framed crossmember bent to provide clearance.

Fabrication is fascinating.
 

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Discussion Starter #63
A couple of layman thoughts:

1. Could the intake runners be radiused 90º so that the red plenums were rotated down and sit down above the heads? You'd keep the F-car plenums, the intake runner length would remain the same, the throttles could be at the front as you said, and it may clear a stock hood (bonnet?).... hmm. You'd have to take them off to get to the plugs, yes.

2. Even though I understand those blue steel tubes boxed-in are quite strong, I feel like the thin-ness of the center of that new "beam" essentially puts a structural "hinge" in the shell of this car. That's how we would describe a strong structure in one portion of a building or bridge, and a strong portion in another, but the joint between them is not near as stiff and the whole thing will tend to "hinge" right there.

You don't have the space to increase the depth of that member UP obviously. What's the situation beneath this cross member? Is that the lowest portion of a 105? The pan sits lower by a bit, then some of us hang the steel strap pan guard even lower. Could you reinforce this crossmember beam with more depth down, below the current bottom edge? You could fab an aluminum skid plate that would divert an impact away from your new pan and the cross member. The BMW E30 guys have some nice ones that are bolt-on.

Even a radiused or bowed steel shape that ties solidly into the uprights at each end. It's not like a bridge where it need strength in the middle - it's a link that wants to bend or flex at each end joint (or the center if not stiff enough).

Just ideas for discussion!
Thanks.
The issue with the plenums is that they are joined in the middle. There is some sort of crossover valve that opens and closes at set conditions. I will probably not be reinstating that because shortening the runners means that the whole thing will not be tuned as intended anyway.

As for the sub-frame. Some viewers (who are engineers) agree that it is probably decent in lateral movement, but may suffer more in torsional movement. The simplest fix would be to add a strut brace, but with the height of this engine makes that impossible. What I may try to do is to see what room I have and make some bolt on diagonal braces back to the firewall, which will add much more strength that what was originally there.
Now that you mention a skid plate, that would actually add a lot of strength in itself.
 

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Hi Jeff, as I'm still unable to attach photos (working on it) you may have seen "Corrupt' the Ferrari powered Mustang. The engine brace set up makes a lot of sense. This idea will surely give the 105 more rigidity and not rely only on the lower cross member set up.
 

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Richard Jemison
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Looks like the crossmember mods start at Page 12, Post 168 of Richard's thread. But keep reading because there is a lot more.
 

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Discussion Starter #67
Have you looked through my thread on the work needed to install an Alfa Montreal dry sump engine in a 105 car? Required cutting away most of the cross member. converting to rear mounted rack & pinion and much firewall and tunnel mods.

https://www.alfabb.com/bb/forums/spider-105-115-series-1966-1994/74007-spider-improvement-effort.html

Rj
Awesome. Thanks. I have been looking to see what I can find, but it is hard finding what I need from the large history of posts.

I watched the steering rack conversion that ColinB did which is very helpful. I will be doing a bunch of reinforcement around the car to make sure it is going to handle the stresses put on it.
 

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Discussion Starter #68
Have you looked through my thread on the work needed to install an Alfa Montreal dry sump engine in a 105 car?

Rj
It looks like you did something very similar to what I did for the crossmember. I haven't read it all yet, but have you had the car on the road? How has it held up?
 

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Richard Jemison
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Chassis mods

It looks like you did something very similar to what I did for the crossmember. I haven't read it all yet, but have you had the car on the road? How has it held up?
Yes its been driven quite hard, and the cross member residue was reinforced with 4130 tubing. Should show up in the pics. Full chassis was reinforced with a 1.5", .090 roll bar and the rest of the cage`s reinforcement tubing is 1.5" .065 wall tubing.

With oil tank built into the trunk area`s floor along with the battery and fuel cell, with m sitting so far back in the car (due to mid front engine placement) the car is about 30 lbs heavier in the rear.
 

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Discussion Starter #72 (Edited)
This week I start designing up the adapter plate for the Ferrari engine and I see if my old Alfa shell is straight or not.

I also have a look at some beautiful Alfa's including a real GTA.

 

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Great episode Jeff, keeping an eye on this build as a litmust test for hopefully fulfilling my dream of a Ferrari engine in my choice of Alfa sedan. Keep up the work as its gonna be a long road ahead.
Cheers
 

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Discussion Starter #75
In this episode I jump into the rust repairs on the Alfarrari shell, and try out a shrinker stretcher for the first time.

 

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I have a question for machinists -

When you're measuring the bell housing bolt locations as J was doing above, what is the accepted way to make sure this is really accurate? You want a center to center dimension, but no matter how accurate the tool, putting the end point right at the center of a hole or bolt or pin is a bit of a judgment call. Is having a "good eye" good enough? A mm or two off is way off.

Thanks -
 

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Discussion Starter #77
Ciao Jeff,

Gotta say that it’s great to get all the practice prepping, fabricating, welding and finishing but for the life of me cannot understand why you didn’t completely remove and replace the middle sill as the issue now is that you have no idea of the condition of the inside of the inner sill!! It might look ok from the outside/underneath, but how do you really know? Plus it would have taken you less time in total to replace/repair as these parts are readily available and fit like a glove.

Also, whilst on the proper 105 jig I would have welded in some reinforcement bars inside the cabin to make 100% sure that the body stayed in shape during the complete body rebuilding process since you went through all the effort in body alignment.

Anyway, good luck with the conversion and compliments to Mrs Jeff with her involvement.
I am getting advice from Tim the whole way along (he is here at least once a week), and this is how he recommended. Whilst the inner sills are in place, it is not going to move. I will be reinforcing all of the weak points of the shell later, and as the b pillar on one side is completely rusted through and flopping it will be triangulated first before I rebuild it.
 

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Discussion Starter #78
I have a question for machinists -

When you're measuring the bell housing bolt locations as J was doing above, what is the accepted way to make sure this is really accurate? You want a center to center dimension, but no matter how accurate the tool, putting the end point right at the center of a hole or bolt or pin is a bit of a judgment call. Is having a "good eye" good enough? A mm or two off is way off.

Thanks -
Guestimating the centre of the holes is never going to be close enough. The way I did it was to measure the outside of the stud at the base to the outside of the opposing stud. Then subtract the size of one stud from the final measurement to get the exact centre of the hole. The holes that were open I used a tight fit drill bit to put into the holes. The one measurement that was the most difficult was getting the centre of the oil gallery. For that I measured to the edge of the hole, but that is much more difficult to get accurate, but it is a less critical dimension so if it is 0.2mm out it is not going to be a big problem.
 

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Patches look good in the last video Jeff, keep it up. As for the inner/middle sill condition; why not stick a small SUB inspection camera in there and have a look. Useful for other hidden areas as well (the boxed in section just ahead of the rear shocks, for instance) and it gives us all something to look at on YT! ;-)
 
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