V8 Swap engine mounts?

I am at the point where I have taken out my 6 cylinder and I'm putting in a 350 V8. (View this string for details on the engine - https://vintage-vans.forumotion.com/vintage-vans-general-discussion-f1/v8-swap-t10733.htm)

This is the engine:



Here are the mounts on the motor:



Here is the cross member with the original mounts on my van, (66 G10):



And Here are the engine mounts in the truck where the 350 came from:



I am new to this. Anyone have any advice? Is there good news like my cross member can easily just accept some factory mount adapters?

Any info would be great.

Heavy

You just need the rubber V8 mounts and your engine will work with that cross member

REALLY!!?? The cross member in my van looks so wimpy compared to the mouting member in the truck. I mean, if its a common thing for 1st gen vans to be able to swap engines without beefing up that cross member, then Great!! Easier is way better.

Thanks.

Heavy

You have to take off the 6 mounts, then the V8 works

If the pads on 6 cyl are okay ya can use those just bolt them to the V8

It worked. Thanks a lot. I was so worried about the tranny mount, I just assumed I'd have to do it for everything.

Cheers,

Heavy

Something else you might want to think about seeing as your going with a bigger automatic, is lowering the engine crossmember to help with trans clearance, I dont know if theres anything written in stone about it but I lowered mine an 1 1/2 " and I'm pretty sure Ive read where some have lowered it 2". It is not hard to do if you need to and your going to be building a trans hanger anyway I would think.

Yikes ! Thanks Digz. I'm about to put the engine and trans in today. Crap.

Will it maybe clip the back of the 2nd gen doghouse and floor panel? Boy, nothings going to be easy on this swap is it.

Well let me ask you this.

Does lowering the engine and trans an 1 1/2" to 2 " make a considerable difference to the lower center of gravity for handling performance? I mean, if not, if the difference after lowering was negligible to that , then I wouldn't see the advantage of delaying my install right now. I mean I could just add the notch cut to the huge list of doghouse and interior mods that I have to do anyways later on.

At least I can get this show on the road and maybe drive the van out of my buddies shop sooner without the cross member mod.

Tell me what you think about the impact on performance and handling, (not tipping over), from lowering the engine and tranny 1 1/2" to 2".

Cheers,

Heavy

I have put the engine in and mounted the tranny to it. I have the end of the tranny propped up to bring it to the ideal 8 degree's above the rear end coupling and it is basically touching the parking brake cable, (zero tollerance). Also on the original mounts, the engine is on an upwards tilt towards the front of the van. I assume you're supposed to achieve the 8 degrees drive shaft with a level engine as well, which means there is really only one sweet spot for the engine and tranny to exist.

In other words, I see what your talking about Digz. That sucks. I really wanted to put this in today. Oh well.

So assuming my 350 isn't odd, the fact is, everyone has to lower the engine mounts when they put in a 350, and yet know one said anything about this until now. That's confusing, unless there is some way around it.

If there's an alternative plan out there I'd love to hear it. changing the engine mounts location delay's me until next week now.

Anyone??

Cheers,

Heavy

Are you going to use the TH400? or a TH350 trans? A TH350 tranny may work fine with a 2nd gen doghouse, Im not in anyway an expert on that, but for my 700R4 swap it needed abit more clearance at the normal trans X-member to seem to sit well, for now you could leave the engine Xmember bolted to the engine ,lift the Xmemeber and engine as a unit ,and get some longer bolts and space it down with washers to get a fit. it is the back of the auto tranny , not the engine that makes the difference. for some reason and Im not real sure, I was thinking the TH400 were kinda fat at the rear. As far as handling I have no clue really,, logic says a lower center of gravity could be a good thing, you will be adding near 300lbs with the swap also.

Ok, I'm going to do a separate string for this stuff with images, but a quick recap of what I just did is as follows:

- I put the engine in on the original mounts.
- I put the tranny attached to it and raised it as high as I could.
- With the tranny attached as high as it will go, the engine is on a front to back downward tilt of 5.5 degrees.
- I calculated that to eliminated this tilt I have to lower the engine member 4.6" which puts it practically right on top of the tie rod bar.
- I could easily just cut a trough in the floor behind the doghouse to be able to level out the engine but then I would have an extreme angle from the level tranny to the rear end and I'm told its supposed to be an angle of 8 degreed relative to the level trany line.

I'm screwed. Any other idea's? Why is this so difficult. Is it just the Turbo 400 that's causing this?

Heavy

Somebody tell me if Im wrong, the info I gathered was ,you want the trans and rear end pinion line to be parrallel, the hieght between the 2 is less important.
Also where are you getting your degree angle from?? the carb base? that has a built in angle to allow for some engine tilt already,

Do you have the full wieght of the engine and trans on the springs? best you can do is have 1 jack under the tailshaft at this stage . A person can overthink it too, if its close things are a little forgiving otherwise noone would be able to jack up the back end of thier vans. Its hard to see well but I only have 1/2" of clearance between the trans case and the upper X-member here.

The carb mounting surface should be level when the van is sitting on its wheels riding the way it you want it.

You don't have to lower the engine if you don't need to but donivan is right, the floor behind the dog house needs to be opened up to clear the trany.


When I installed the 2nd gen dog house I did not cut the floor at the back, I moved the dog house forward for better rad installation options. I could get away with this only because I lowered the engine 1".






By doing thid I was able to lean the rad farward at the top for better flow and the greater clearance at the top of the engine alows for lots of airflow through the rad and over the top of the engine.

It is important to try to keep the carboretor cool and especialy have fresh cold air delivered to the intake.

M1d

Ok,

Drastic change to the plan, and I have updated the story on some other string, but here's where I'm at.

I decided against the Turbo 400 Tranny my buddy had and instead decided to go with a rebuilt 200. But when I got to the guys place who rebuilt the 200, he also had a rebuilt 700 with beefed up performance parts, so I bought that one instead.

I heard what you all were saying and so I dropped my engine cross member 1 1/2", which is as much as I have heard you guys say you've done, (someone said they heard about 2" but that made me a bit nervous about clearance).

So now, (and this is a topic on another string), I'm worried about the drive shaft angle. The engine is as low as I want it to go, the tranny is as high as it can go, and so I am just going to have to go with the drive shaft angle, what ever it winds up being. I hope it works.

If anyone has the same combo, (V8 lowered 1 1/2", 700r4 raised to within a 1/2" from the underside of the van), then what is your drive shaft angle?

Lots of variables on that angle. having a shorter diveshaft changes the angle, lowering or raising your ride hieght changes the angle, The only thing That I might have to change on mine to make a difference it how the spring perches are clocked and thats only if it is a problem. I havent heard you say anything about changing anything radically as far as suspension goes ? Im of a mind that the 8 degrees they talk about isa ballpark number ? it would be to limiting to have to be exact. IMO Another thing you have mentioned is "spring wrap" where the pinion makes that upwards swing "if " you can get enough bite. a pinion snubber to the body or traction bars would handle that. What you dont want is the pinion angle to be so high that it tries pulling the drive shaft out of the tranny when it torques. I dont think you have anything to worry about if you dont actually change perch locations.
* Note* Opinions expressed by me are just that , opinions, I am not a tech head, just try to be practical.
Joe

Actually when I originally was saying 8 degrees, I have since been told that was wrong. Now I'm told 5 degrees is the ideal. But like you said, its probably a loose idea because I doubt everyone is pulling out the calculators and torque meters on these swaps.

Heavy

Disclaimer: The following is basic engine swap stuff. I have not done a V8 van swap, and do not have a Chevy van!

With the floor of the van level, the engine should be tail down around 5 degrees. You will see this at the carb mount of the intake as already noted.
The engine/trans centerline as viewed from above should be parallel to the centerline of the van. If the front pulley is off to the right, the tailshaft should be too. This is to align with the rear axle pinion, which is 90 degrees from the rear axle. They do not have to point at each other, just parallel. A few degrees off will not kill anything, but may set up a harmonic.
Now, for that angles seen looking sideways. The tailshaft of the trans is normally pointed down toward the rear axle (the 5 degrees mentioned above). The rear axle is normally level or slighty up, pointing toward the trans.
Since the rear axle moves in an arc from the front spring eye and you have to compensate for some spring wrap under acceleration (when the forces are really working the driveshaft and U-joints), the agreed angle is 3-5 degrees pinion down. This is NOT from level, it's from the line that is parallel to the sideways viewed engine/trans centerline. The common angle for this is 5 degrees down in back. The parallel line for this would be pinion angle 5 degrees up in front. So you would normally want the pinion level to 2 degrees up.
When you lift or lower the rear axle a lot, these angles should be rechecked.
Since you are working from front to back, just try to make it all fit well and centered (from above), and get the carb mount angle close to level with the van level. If the van has a rake while checking all this, you are adding additional complexities. A regular carb will work fine at a few degrees off. Otherwise, the 4X4 guys would be stalling all the time!

EDIT: this picture is for 4 links that do not have spring wrap. They are set up for only a degree difference.
The reason for a slight difference (not parallel) is so the needles in the u-joint move around, spreading the load and grease. Leaf spring difference should be 2-5 degrees.

Don, the shim idea sounds good but Im not sure about how it would work out being a driven axle. If you lift the center pin on the springs out of the perch you may be relying on the U-bolts to hold the axle in place, I fought this problem once on a 73 Nova, everytime My little brother would borrow the car for an evening, I spent the next day pushing the axle back into place because he was out doing Hole shots. The problem there was a crappy rubber pad system on the spring mounts that didnt lock in the axle well enough on the perches and allowed it to walk forward on the mount. Just something to watch in case someone trys it and has problems.

Digz, it's like everything else, pick the level of quality and effort you can handle!
the right way is to cut and reweld the spring plates on the axles. Lotsa work!
The next level down is a taller bolt that sticks out of the spring pack and engages the shim AND the bracket. Gotta find the bolt and swap it into the spring pack.
Some blocks and shims have a nub that engages the hole. One that changes the angle is a bit thin for that!
The last, easiest way is to add the shim and hope for the best. If you plan on letting your brother borrow it, this is not good.
Those rubber-bushed springs were for granny cars, and had other issues.
It's too late for your project, but for others contemplating swapping, it might be a good idea to take measurements of the crank and tailshaft of the old stuff before removing. Remember that engine mounts sag and that a straight 6 is longer than a V8. Just try to get an idea of where those engineers put stuff and be close!

Digz wrote:Don, the shim idea sounds good but Im not sure about how it would work out being a driven axle.

They make extended or longer locating/spring bolts. Should be able to get them at any 4x4 shop along with the shims. A 2* shim is not very thick and should not have any effect on the locating bolt going into the axle spring pad.

the easies carb solution is drop it, get an efi kit, no more ANGLE PROBLEM, efi kits are getting very affordable and much more reliable than any carb!!

I have used the angle shims on the rear axle of these vans
before with no adverse effects, just need to use a longer spring
centering pin, the one that goes through the spring.
just think the pinion shaft and the crankshaft are the rails on a ladder
they have to be parallel within 2 degrees and you will be fine.

This may be a dumb question but if you use a 2nd gen v8 cross member and mounts in a 1st gen do you have to worry about the angles?