1- What ideal degree do you set the engine in a chassis at? 2 degrees tail down? 2- Do you level (for reference) the car at the rocker? or the frame? this is a unibody constructed car 3- What angle finder tools can you recommend? Both useful in purpose and inexpensive but accurate. (I have a cheap magnetic dial face gravity operated protractor) This is a drag purpose build...but I am interested in both street and strip setup measurements. I will admit this is not a H.A.M.B approved car in question (70 Dart 440)but the principles can obviously be shared with the rest of the crowd here.
i level the carb pad- put me at 3degrees tail down. make sure your rear axle u joint angle is equal and opposite to the one at the tranny when at ride height (under acceleration load, since its for drag racing). just put your angle finder on the output of the tranny and one on the rear yoke.
When I was a 18 year old hot rod wanna be, I met Lil'John Buterra at Lions Drag Strip. And recall him saying that an engine should be square to the firewall. Look at Ford flatheads with torque tubes and only one u-joint. Now the problem is that the carburetor flange on later overhead engines has a 1 1/2 to 3 degree tilt, so to level the carb you have to raise the front of the engine. It is important to understand transmission output shaft angle which will effect the rear axle pinion angle. If the tailshaft is down 2 degrees the pinion should be up 2 degrees. Generally the engine position has more to do with driveline geometry which explains why the intake manifold/carburetor is not parallel to the cylinder heads. The FOGGER
On some engines angle might not be so much of an issue but I believe the factory had the majority of their engines mounted going slightly uphill towards the front to help with oil drain back and to prevent air pockets from being trapped in the rear of the cylinder heads, being that the thermostat was usually mounted towards the front. I could't say off hand what the ideal angle would be but it should be o.k. as long as the front is a little higher with the car at it's final ride height.
If it is drag only application, crankshaft centerline should be pointed straight at the pinion at ride height. This may prove difficult depending on chassis. Level the car at the rockers. Level the motor with chassis and run with it. What type rear suspension?
Lots of goog info here, follow the "More" links, hope this helps <CENTER><MAP name=FPMap0><AREA shape=RECT coords=5,9,281,26 href="home.html"><AREA shape=RECT coords=5,27,281,44 href="critical.html"><AREA shape=RECT coords=5,45,281,62 href="driveshafts.html"><AREA shape=RECT coords=5,63,281,80 href="yokes.html"><AREA shape=RECT coords=5,81,281,98 href="bearings.html"><AREA shape=RECT coords=5,99,281,116 href="measure.html"><AREA shape=RECT coords=5,117,281,134 href="guide.html"><AREA shape=RECT coords=5,135,281,152 href="links.html"></MAP> <MAP name=FPMap1><AREA shape=RECT coords=20,145,180,160 href="mailto:[email protected]"></MAP> <FONT face=Arial><TABLE cellSpacing=0 cellPadding=0 width=600 border=0><!--<tr> <td rowspan="2" height="23"> </td> <td height="121"> DRIVESHAFTS FOR HYDRAULICS: "Driveshaft surprises are part of every hydraulics project."</td> </tr> <tr> <td height="1"> </td> </tr>--><TBODY><TR><TD height=166 rowSpan=2></TD><TD height=119>POWER TRAIN SET UP: "This booklet concerns the placement of power train components in the chassis. The engine/transmission, the third member and the drive shaft must be installed to work in harmoney if driveability is your goal." </TD></TR><TR><TD align=middle height=47></TD></TR><TR><TD height=166 rowSpan=2></TD><TD height=119>POWER TRAIN SET UP: "Having a little information at the beginning of your street rod project can make setting up power train angles one of the simplest steps in the building process." </TD></TR><TR><TD align=middle height=47></TD></TR><!--<tr> <td rowspan="2" height="162"> </td> <td height="90"> DRIVE SHAFT ANGLES RE-VISITED: "Drive train set up continues to be a baffling and controversial subject."</td> </tr> <tr> <td align="center" height="72"> </td> </tr>--><!--<tr> <td rowspan="2" height="161"> </td> <td height="105"> OVERDRIVE VIBRATIONS: "If you already have or plan to install an overdrive transmission, there are a few things you should know."</td> </tr> <tr> <td align="center" height="56"> </td> </tr>--><TR><TD height=160 rowSpan=2></TD><TD height=104>UNEXPECTED RESULTS: "Anyone who has ever bolted a modified part on a car knows that some surprises can be expected." </TD></TR><TR><TD align=middle height=56></TD></TR><!--<tr> <td rowspan="2" height="160"> </td> <td height="104"> TWO PIECE DRIVE SHAFT TECHNOLOGY: "Two might be better than one! "</td> </tr> <tr> <td align="center" height="56"> </td> </tr>--></TBODY></TABLE> HOME | The Critical Link | Driveshafts | Yokes | Bearings | Measure/Order | Set-Up Guide | Links Copyright �2002 Inland Empire Driveline Service, Inc. Web design and hosting by ULTIMATE Internet Access, Inc. </TD></CENTER> Hope this helps
i just went through this on my roadster, on my roadster i'm parrallel with my chassis because if you dont, you have an angle on your pipes, doesnt apply to you though also remember you can set an engine level because most standard rearends have a pinion offset on the rear so that angle going from left to right applies also. i also use to think the only way to do it was off the intake but that is not the case.. especially if you have lowered the car in anyway. 3degrees is maximum driveline angle.. the less angle you have the more it frees up horspower/torque... more angle the more horsepower and torque it takes to turn it. probably very little but still applies to dragracing. i think where the 3 degrees come about was engineers putting the engine and transmission on an angle for clearance for the floor of the car (more interior room).. we had a discussion on this over at www.tbucketeers.com it might be a good read up for you.
Go over to http://www.bigblockdart.com/ and you will find info for your particular vehicle. I agree that you normally want about 3 degrees tail down. A lowered, channelled custom may need a level crank. A drag car usually wants the crank pointing right at the pinion. Take a look at how they fabbed the diggers. Yes, they had no suspension, but racing hates waste, so the straightest shot is best there.
Thanks for the ideas everyone! Setting the motor level (which I do agree with the arguement) will put the carb tilted downward in the front. I guess on acceleration it all washes though. Question was asked on what rear suspension.....8 3/4 with super stock springs and spring relocator....should this be set where? due to some pinion climb...2 degrees downward?
I believe w/a drag car 5-7 deg. down is recommended for super stock springs. Measured between the yoke and drive shaft. A street car might be better at 2-3 deg. Also keep your front U joint angle in mind when setting it up.
What K-member are you using? If it's a big block K-member I think I'd just bolt everything up and try it. Just MHO however...
I just meant (depending on your transmission angle rear end height etc.) that you may not have any angle in your front U joint which could cause wear or vibration issues and could be corrected when setting up the pinion angle.
The front chassis is al fabbed using 2x3 box tubing.....crossmember and torsion bar mounts are box steel also. The car had significant damage from rust and a previously repaired collision. It now has a front and rear motor plate.This was positioned by using a engine adapter kit to go from 6 cylinder to 440 (to the k member). This was done to get the "factory correct setback and height. However due to the rear cross member being destroyed and now box steel we need to figure out position. If I understand correctly from everyone: 1- Set engine from 0-2 degrees tail down.based off of rocker panel at zero 2- Super stock springs 5 degrees pinion angle 3- Cut ,wittle ,fit ,entire front end due to fenderwell headers
You can set up the engine angle at almost any degree just as long as the transmission is perfectly inline with the pinion yoke. However, when the engine and pinion yoke is in direct line, it does not allow for the rotation of the u-joints. This straight alignment is mostly used on drag race cars. Check out this article for more info: Determining Engine and Pinion Angle
That's the easiest way. The intake is built so that when the engine is at the proper angle the carb is level. Something that you should keep in mind is that when the axle is under load the crank and the drive shaft (actually pinion) should be @ the same angle. IE when you're deep in it comming off the line and you're springs have wrapped up as much as they are gonna wrap you want it to all line up. So its not just a matter of setting your crank angle but also the rear end.
And there's one of the reasons to use a long pinion snubber on a Mopar, controlling rear spring wrap...
I am being advised against the pinion snubber that we already purchased. I am told that you do not use one a mopar with super stock springs. I like all the info and links. Thanks for the help!
If I recall correctly, Mopar used to say that ALL you needed to do to get one to hook up was to use the Super Stock springs and a long pinion snubber. But... I could be wrong as it's been a bunch of years since I had my 440 powered '67 Barracuda.
I agree that it only makes sense to control the pinion....we already have it, so it will probably be an expirement when we are done as to what the car seems to like Thanks again