engine height in the frame

[karen ellis]

I am looking for some guide lines as to where to place my engine, height wise in my frame. I am putting a 351w with an AOD behind it into a contemporary chassis. Yes i know some will ask why not a big block, but i don't want to race and i hate standard transmissions! Anyways, I placed my engine in the frame last night and it looks a little high. Does anyone know what the proper engine height should be? This is certainly the ultimate in jig saw puzzles!
Thanks for the assistance.

[Ron61]

Karen,

Since no one else has answered your question I will make an attempt to help. I am not very familiar with the Contemporary chassis I don't know exactly how their engine mounts are put in. But to set an exact height is very hard to do. Main things are to be sure that when your air cleaner and carb are on they will clear the hood when it is closed. Be sure that you have the transmision and motor lined up, and this applies to any transmission, stick or automatic. On my Classic Roadsters I had to have the engine mounts cut off and welded about 1" lower so I could get enough clearance for my air cleaner, and then I used some kind of engine mount that made it set lower on top of that. But that was so many years ago I don't even remember what all I did. Now they are just making the hood scoops larger. I am guessing by the way you worded your question that you don't have the body on the frame yet. If possible, try setting the body on and looking at the top of the carb and what clearance you have.

Ron

[Cracker]

Karen - I can't asnwer the question either way but can tell you that Contemporary motor mounts places a BB FE about 1" higher than an ERA, orginal car, etc. Why did they do that? I don't know. It would not be difficult to lower the mounts on a Contemporary but then you have to deal with sidepipes and header issues.

Good for you - do it your way and enjoy every moment of it.

Another good resource for Contemporary cars is Upstate - Bill Connelly. He was recently trying to sell the business - do a search and give him a call - he'll probably know.

[Steve Riley]

They're right, Karen. I had to fab up a pair of motor mounts myself for my E-M because with the manifold and carb setup I have, the air filter wouldn't clear the hood scoop. I had to drop the engine 1.5".
Steve

[John S Peterson]

Wont changing the height of the motor also change how your headers and sidepipes fit the body/frame, also the relationship of the trans output shaft to the pinion centerline. Isn't this stuff all figured in when you buy a kit from a manufacturer, and changing anything affects much more? I built my own thinking I would bypass engineering problems associated with kits, of course thats when I was real smart. After learning the definition of real smart and 6 more years to finish I have to have some faith in kits. Although the engine looks high in the chassis I wouldn't change anything until you test fit the body. Looks can be decieving, close but decieving....Good luck
John

[karen ellis]

Thanks for all the good information. John you are probably very correct in saying not do anything until i test fit the body. As it sits now i can lower the engine about 1.5 inches quite easily. Having said that i am still going to wait to see where the body lines up.
Thanks again for all the help!

[grumpy]

karen,

As noted in PvtMail, need the dimension as you lay a straight edge across the frame rails of the chassis measuring vertically to the "bolt hole" on the motor mount plate for the engine. That will give you what was intended to be installed in the chassis.

The bolt thru the mount is 5.25” above the center of the 4” dia main chassis rails, less the 2” top the top of them you will have 3.25” where the mount will bolt thru the mount. That is for the FE, and 2.375” for a 351W small block.

For a big block they mount holes/slots are 17 5/8” across and off centered in the rails by 1 1/8”. A 351 is 18 5/8” for this dimension and uses a different mount. You will have to alter this for a small block and use motor mount PN 2727-DPEA, which is 3.610” in “new condition”, after age and compression, that will be closer to 3.30” in dimension.

Installed the center of the crank should be 3.12” from the top of your main frame rails at the damper bolt point and approx 2.95” at the centerline intersecting at crossing centerline thru mount location.

Cannot go much farther without input or a eMail address to send a sketch of that geometric layout fo the Contemporary.

grumpy

[cobrashoch]

Lowering a engine will also lower the tranny at the bellhousing. The lowest part on my car is the tranny on the underside. Makes it hard to go over speed bumps because the front end comes down off the speedbump and makes the car level while traveling over the bump. Oil pan and headers can be raised, built or modified but you are pretty much stuck with the trannys bellhousing. Another way to add hood clearance is to put spacers under the body mounting points to raise the whole body. This needs to be done by in large as the car is being built because everthing going through the firewall needs to be a little longer, such as steering linkage, wires and etc. If you are in the build stage raising the body is really not that big of a deal though, when you mock up everthing including the engine. Matter of fact I mocked my car up originally for a 385 engine but my original engine was a junkyard 351W that sat higher, and I dared not lower the tranny/engine any lower than where it is now.
cobrashock

[karen ellis]

Grumpy, thanks for all the info. I tried the motor mount p/n and it the jobbers were not able to find it. Do you have any other info on this motor mount other than 2727 DPEA?

Karen

[Steve R]

Karen,
Welcome, and let's see some pics of your project.
Steve