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turbo4ag
10-19-2007, 04:46 PM
I just thought about something that could help out alot in my engine build and megasquirt wiring. Wouldn't it be possible to wire up and start the car on an engine stand? Just to get it to start and idle. Not to rev it up or anything.

Here's what I had in mind:
1. Mount the 3SGTE in a sturdy engine stand. I have a Snap-on rotary stand thats heavy duty enough to hold a V8 engine and it also has locking casters so it should be sturdy enough for a running engine. It will also alow me to put the engine at any angle meaning I could put it at a slant the way the engine is supposed to sit. I wouldn't need a charge pipe or intercooler, etc. Just a filter on the TB.

2. Wire up my megasquirt w/ EDIS coilpacks. I wont need any relays or ignition key as this can all be sourced from the battery with a remote starter trigger. Block off brake booster hose.

3. I have an inline fuel pump available that I could temporarily wire up on the engine stand. It should give enough fuel pressure to start the engine with just a gas tank full of fuel. And the return doesn't have to be pressurized, just not submerged in fuel, correct?

4. From there just find a stand to hold up the radiator so I can mount the hoses.

5. I have a exhaust vacuum in my shop so I can hook up the hose to the downpipe and pull the fumes outside.

In theory this should work. The only worries I have is will a starting/backfiring or running engine be enough to jolt the engine stand enough to rock it over? And also would the fuel pump setup cause any problems? Any ideas why it can be done?

Cavanagh
10-20-2007, 09:28 PM
You can build a little box to hold it if you can. We made one at school with (bad welding job) and it held up for 6 or 7 chevy 350 engines and still works today! They were backfiring and revving like crazy so it didn't seem to be a problem, but an engine stand, i personally would not put a running engine on one.

turbo4ag
10-20-2007, 10:12 PM
Yeah... I was considering that. The only thing is this is no regular engine stand. This is a heavy duty Snap-on engine stand. Here at the school's shop where I work, we've got big mercedes V8 supercharged engines on this thing. It doesn't break casters or anything.

Man, this is one of the times I wish the Celica had removable subframe that I could just drop the engine on the ground and do everything. We do have true mockups, but they are made for specific engines, not a universal. And we do have a welder, but it'd seem like a waste of time for one engine.

Another thing I was considering was attaching an engine crane for stability and a safety backup. I think the engine stand along with crane attached has a pretty slim chance of knocking both over. What do you think about that?

Amaymi
10-21-2007, 08:53 PM
I personally would not be worried about the casters or the engine stand tipping over, but instead the joint between the piece that the engine bolts to and the actual stand. That joint is not intended to handle the movement of a running engine. Especially an engine that has a good chance of running rough for a period of time since you will be tuning.
If you've ever been in a car where a motor mount is broken and part of the motor is touching the chassis, you know that even a well running motor can shake a 3000lb car pretty good. If you welded that joint I'd say go for it, but then you would be ruining a pretty expensive Snap-on engine stand.

turbo4ag
10-22-2007, 05:39 AM
The stand Im talking about is not the standard one where you turn the handle and then insert the pin where you want. This one has a crank on it similar to a puller cable for a boat reel. Thats the best I can do in describing it. And the engine wouldn't be started and tuned, it would be started and idled, just to check to make sure the sensors are reading accurately, etc..

But thinking about it, it just seems too dangerous. I might see if they have an extra mockup or something else I can put the engine on. If not I'll just wire it up as best as possible and then just take my time and swap it in the shop. We have almost every possible tool there to work on cars. And if we dont have it, I can likely try and fit it in the monthly budget to order one.

FourVeeSix
10-30-2007, 07:56 PM
Lol worried about it coming off the stand? Dont be.

Many years ago i had a 3.5 litre v8 rover engine ( same as some buicks) which ran on twin SU carbs.
I had that engine in the garden shed, running with it sat on its sump, no headers at all, no coolant just a battery and a fuel line to a can....really shouldnt have had that can in the hut tho...:D
Anyway, i ran that engine usually a couple of times a week like that, hang on to it for grim death then rev it while it tried to flip over...great fun...neighbours used to hate on me tho, but it was awsome to see the flames coming out the ports and hear that rumble. :D

turbo4ag
10-30-2007, 09:38 PM
After looking at the mockup we have in the shop, I noticed its basically just an engine stand. At first I thought it had a mount on the transaxle, but it doesn't. All it has is an L shaped bracket that the oil pan can just rest on. Its basically an engine stand with a better stance, and heavier base.


I'll show you a picture of what we have to show that its probably possible to start a 4 cylinder on there.

turbo4ag
10-30-2007, 09:54 PM
Damn phone battery died. I was going to take a picture of the engine stand first, then the mockup. But I was only allowed to take one pic. It says battery too low to take more.

Anyway this is the stand I was talking about. Its a pretty heavy duty Snap-on stand. We got a Honda D15 on it right now. But this is the one I'll be using eventually to build my engines. Pardon the other stands in the background.

http://i2.photobucket.com/albums/y26/rollaracerGTS/f0a1c8d0833e.jpg

I'll post a pic of the mockup tomorrow.

MrWOT
10-30-2007, 10:29 PM
As long as the stand is stable enough to rock around a bit it will be fine, it will torque when you start it but even if you rev it, there is no load, it won't torque against the stand much. I've run engines bolted to stands many a time, though I always support them underneath with wood blocks on a jack (i do that even if they aren't running though).

FourVeeSix
10-31-2007, 03:11 PM
As Mr WOT suggests, shouldnt be a problem, that looks to be quite sturdy. Just go easy on the throttle. :)

turbo4ag
10-31-2007, 07:31 PM
Yeah. I really might try it.

Here's the pictures as promised of the mockup we have in the shop.

As can be seen here, the mount for it is basically a standard engine stand style mount that threads into the block.
http://i2.photobucket.com/albums/y26/rollaracerGTS/f0a1c8d0833e-1.jpg

In this picture you can see that there are no mounts on either side, meaning there is no lateral torque that can overcome the main bracket.
http://i2.photobucket.com/albums/y26/rollaracerGTS/9acdfe89cebf.jpg

And lastly, it does have a rear mount, sort of, which like I described before is just a L shaped bracket that kind of props under the side of the oil pan. But its is not threaded and not padded. So a cinderblock or something similar could likely be used in its place.
http://i2.photobucket.com/albums/y26/rollaracerGTS/298a71228371.jpg


So, I think its very possible. Once I finnaly get a Celica and a 3S to start building along with the Megasquirt, once its wired up I can just use the inline pump along with an inline filter, and attatch the radiator and battery and it should be able to start and run no problem, which is all I really need it to do. I wouldn't be trying to tune the thing.