How to LOWER engine by one inch

[chargerdon]

Hi I have a 74 CHallenger with a 360 in it.   Engine has an Edlebrock Air Gap RPM intake manifold that sits higher than most other intake manifolds and a Mopar Performance Air cleaner sitting on top of an Edlebrock 600 cfm carb.   Car has the standard (not the rallye hood).

To get the hood clearance i have had to "make" a drop plate base and use a shorter height air cleaner.   The resulting combination does not allow enough air flow for over 4000 RPM runs...  performance drops off.   I know it is an air issue, because if I remove the air cleaner the engine then runs strong up to 5500 rpm arbitrary red line.   

So, I think i either have to put on a hood scoop to give room for normal base plate and filter, OR lower the engine by about 1 inch.  I do believe (without knowing what the measurements should be) that the engine is sitting maybe 1/2 higher than it should be possibly due to bent K member ?    Anyone have measurements as to where say the top front of valve cover should be in the engine compartment? 

SO...can anyone tell me where to either buy or how to make engine mounts that allow the engine to sit about 1 inch lower.    Currently i am using the Mancini racing engine mount with the safety bolt in it rather than oem mounts as they just break in a few months.   Would it be possible to put 1" thick shims between the K member and the frame? 

Suggestions welcome.

[Cuda Cody]

Lowering the K Frame would also mess with the transmission location and some of the steering, ride height, camber, and the torsion bars.  Not sure that is the best way to do it.   

[Burdar]

I know people have lowered the K without problems but I wouldn't be comfortable doing it.  If it were mine, I'd be saving up for another hood. 

How much drop did you end up getting on your custom drop base?  3/4" is the max on an Edelbrock with an electric choke.  I was able to get an inch drop but I had to cut up the drop base to get it.  I also had to remove a little rubber from the inside lip of the air filter to make it work.  How tall is the filter you are using now?

[HP2]

You can shim the K frame to drop engine height. It does impact  front suspension geometry and drive line angles so changes to alignment, trans mount, and pinion angle may be necessary along with this change. Not impossible, but do be aware it may require attention in other areas after being done. I believe the super stock A bodies of '68 used this trick.

To modify the  mounts to drop an inch would require a fair amount of cutting and welding to the mount towers to create the drop, and it could create interference with the steering box and oil pan/ drag link. There is often <1" clearance from the oil pan to drag link.  Again, it is possible, but will impact other items along the way.

A drop base can get a bit more air filter height, but the flat, thick top of the Mopar air cleaner will interfere with air flow over the top of the carb and is likely creating a pinch point there. A good drop base air cleaner has a corresponding bulge on the lid to allow the air to get a straighter shot at the carb throat. Moroso's air filter is a good example of this design.

Because of engine angle vs hood angle, it may be possible that only a section of the filter lid is interfering, which means a modified top may allow improved flow around a percentage of its diameter while allowing clearance where needed. But this most likely is not possible with the aluminum Mopar lid.

I'd also verify that the modified base you have not is not pinching the fuel line, shorting to the distributor, or interfering somewhere else that prevents the higher rpm. Some factory air cleaners were fairly restrictive but still allowed high rpm blasts.

[GoodysGotaCuda]

I had a Performer RPM, which I believe is the same height as the airgap, with a drop base Mopar and a flat Cuda hood.

This setup made 240whp on the 318 and had no problems with airflow....I can assure you the air cleaner you see would handle 600cfm.




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[1 Wild R/T]

Might  want to consider milling the choke tower off.... Gain about an inch between the carb & air cleaner that way & do you really need a choke in NC?

[Cudajason]

Hi I have a 74 CHallenger with a 360 in it.   Engine has an Edlebrock Air Gap RPM intake manifold that sits higher than most other intake manifolds and a Mopar Performance Air cleaner sitting on top of an Edlebrock 600 cfm carb.   Car has the standard (not the rallye hood).

To get the hood clearance i have had to "make" a drop plate base and use a shorter height air cleaner.   The resulting combination does not allow enough air flow for over 4000 RPM runs...  performance drops off.   I know it is an air issue, because if I remove the air cleaner the engine then runs strong up to 5500 rpm arbitrary red line.   

So, I think i either have to put on a hood scoop to give room for normal base plate and filter, OR lower the engine by about 1 inch.  I do believe (without knowing what the measurements should be) that the engine is sitting maybe 1/2 higher than it should be possibly due to bent K member ?    Anyone have measurements as to where say the top front of valve cover should be in the engine compartment? 

SO...can anyone tell me where to either buy or how to make engine mounts that allow the engine to sit about 1 inch lower.    Currently i am using the Mancini racing engine mount with the safety bolt in it rather than oem mounts as they just break in a few months.   Would it be possible to put 1" thick shims between the K member and the frame? 

Suggestions welcome.

Well I think I would be looking at this issue first! 

Someone had posted the measurements of where the engine should sit on a cuda...I assume they would be the same for challenger.

I will see if I can find them.

Jason

[Burdar]

I'd also verify that the modified base you have not is not pinching the fuel line

Good suggestion.  I wasn't able to use the stock fitting that comes with the Edelbrock carbs.  I had to buy a banjo fuel line that drops straight down, then angles forward, in order to clear the drop base.  If you are using a rubber line off of the carb, the drop base could be pinching it closed.

[shawge]

Got these measurements from TTI's install documentation:

center of crankshaft to top of k-frame: 5-1/4"
center of crankshaft to each frame rail, difference should be 2-1/2" (engine is offset towards R-side)

[RzeroB]

You can shim the K frame to drop engine height. It does impact  front suspension geometry and drive line angles so changes to alignment, trans mount, and pinion angle may be necessary along with this change. Not impossible, but do be aware it may require attention in other areas after being done. I believe the super stock A bodies of '68 used this trick.

  Yep, that was part of the process to stuff the Hemi into the '68 Super-Stockers. IIRC I believe they used 1/2" shims in that application.

[Brads70]

Not being a smart a$$ but I'd save up for a T/A hood and put a taller filter in it. 

[303 Mopar]

Not being a smart a$$ but I'd save up for a T/A hood and put a taller filter in it. 

I am not a fan of the flat hoods, so I would be looking for a new hood as well. Otherwise, you could also look for low rise intake like a regular performer that may give you more room.  I would avoid lowering the engine due to all the issues mentioned above, and the fact that the oil pan is already low enough on our cars.  Decreasing the clearance by an 1" is pretty significant to me.

[shawge]

   Wouldn't the combo fit under a Rallye hood?  Would fit the T/A hood with plenty to spare.

[Roadman]

Not being a smart a$$ but I'd save up for a T/A hood and put a taller filter in it. 

              What a smart a$$      I agree, T/A hood.   

[Brads70]

Not being a smart a$$ but I'd save up for a T/A hood and put a taller filter in it. 

              What a smart a$$      I agree, T/A hood.