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Engine angle help!

Discussion in 'The Hokey Ass Message Board' started by NITRONOVA, May 10, 2009.

  1. NITRONOVA
    Joined: Sep 3, 2008
    Posts: 184

    NITRONOVA
    Member

    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.
     
  2. skunx1964
    Joined: Aug 21, 2008
    Posts: 1,455

    skunx1964
    Member

    should be able to level the intake right? at the carb mount surface?
     
  3. HotRodFreak
    Joined: Mar 25, 2005
    Posts: 1,935

    HotRodFreak
    Member

    Ideally the carb base should be level.
     
  4. 69fury
    Joined: Feb 24, 2009
    Posts: 1,452

    69fury
    Member

    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.
     

  5. Fogger
    Joined: Aug 18, 2007
    Posts: 1,804

    Fogger
    Member

    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
     
  6. landseaandair
    Joined: Feb 23, 2009
    Posts: 4,485

    landseaandair
    Member
    from phoenix

    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.
     
  7. The engine angle and the rear end angle must add up to 180 degrees...
     
  8. Da Tinman
    Joined: Dec 29, 2005
    Posts: 4,222

    Da Tinman
    Member

    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?
     
  9. 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>[​IMG] <MAP name=FPMap1><AREA shape=RECT coords=20,145,180,160 href="mailto:[email protected]"></MAP>[​IMG]

    <FONT face=Arial><TABLE cellSpacing=0 cellPadding=0 width=600 border=0><!--<tr> <td rowspan="2" height="23"> [​IMG]</td> <td height="121"> DRIVESHAFTS FOR HYDRAULICS: &quot;Driveshaft surprises are part of every hydraulics project.&quot;</td> </tr> <tr> <td height="1">
    [​IMG]</td> </tr>--><TBODY><TR><TD height=166 rowSpan=2>[​IMG]</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>[​IMG]</TD></TR><TR><TD height=166 rowSpan=2>[​IMG]</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>[​IMG]</TD></TR><!--<tr> <td rowspan="2" height="162"> [​IMG]</td> <td height="90">
    DRIVE SHAFT ANGLES RE-VISITED: &quot;Drive train set up continues to be a baffling and controversial subject.&quot;</td> </tr> <tr> <td align="center" height="72"> [​IMG]</td> </tr>--><!--<tr> <td rowspan="2" height="161"> [​IMG]</td> <td height="105">
    OVERDRIVE VIBRATIONS: &quot;If you already have or plan to install an overdrive transmission, there are a few things you should know.&quot;</td> </tr> <tr> <td align="center" height="56"> [​IMG]</td> </tr>--><TR><TD height=160 rowSpan=2>[​IMG]</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>[​IMG]</TD></TR><!--<tr> <td rowspan="2" height="160"> [​IMG]</td> <td height="104">
    TWO PIECE DRIVE SHAFT TECHNOLOGY: &quot;Two might be better than one! &quot;</td> </tr> <tr> <td align="center" height="56"> [​IMG]</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
     
    Last edited: May 11, 2009
  10. brucer
    Joined: Jun 5, 2008
    Posts: 332

    brucer
    Member
    from western ky

    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.
     
  11. This is how I remember it and I have done numerous cars this way with no problems.
     
  12. Here's something that illustrates the ideal. Maybe it will be helpful.

    [​IMG]
     
  13. 35Chevy.com
    Joined: Nov 27, 2007
    Posts: 542

    35Chevy.com
    Member
    from New Jersey

    That clear's it up for everyone!

    Engine level at intake manifold then go from there

    Gary
     
  14. RodStRace
    Joined: Dec 7, 2007
    Posts: 3,911

    RodStRace
    Member

    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.
     
  15. NITRONOVA
    Joined: Sep 3, 2008
    Posts: 184

    NITRONOVA
    Member

    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?
     
  16. landseaandair
    Joined: Feb 23, 2009
    Posts: 4,485

    landseaandair
    Member
    from phoenix

    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.
     
  17. NITRONOVA
    Joined: Sep 3, 2008
    Posts: 184

    NITRONOVA
    Member

    Keep front u-joint in mind??? as far as what degree?
     
  18. 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...
     
  19. landseaandair
    Joined: Feb 23, 2009
    Posts: 4,485

    landseaandair
    Member
    from phoenix

    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.
     
  20. NITRONOVA
    Joined: Sep 3, 2008
    Posts: 184

    NITRONOVA
    Member

    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
     
  21. landseaandair
    Joined: Feb 23, 2009
    Posts: 4,485

    landseaandair
    Member
    from phoenix

    Sounds about right. An adjustable pinion snubber might not be a bad idea either.
     
  22. RoadkillCustoms
    Joined: Jul 10, 2008
    Posts: 270

    RoadkillCustoms
    Member
    from Mesa, AZ

    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
     
  23. 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.
     
  24. And there's one of the reasons to use a long pinion snubber on a Mopar, controlling rear spring wrap...
     
  25. NITRONOVA
    Joined: Sep 3, 2008
    Posts: 184

    NITRONOVA
    Member

    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!
     
  26. :eek:

    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.
     
  27. NITRONOVA
    Joined: Sep 3, 2008
    Posts: 184

    NITRONOVA
    Member

    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
     
  28. RodStRace
    Joined: Dec 7, 2007
    Posts: 3,911

    RodStRace
    Member

    Here's a pinion angle pic
     

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