1" setback vs standard motor mount adapter plates

[87National]

I'm swapping a 5.3/4l80E into an 88 cutlass classic. I realize that many use the 1" set back plates (that place the bell housing in the factory location).....but in my situation, I will be modifying the trans crossmember and getting a custom length drive shaft made. Other details include manual steering (no interference with ps pump pulley) and will be notching the engine crossmember for an ls1 oil pan anyway. So unless I'm missing something....... it doesn't seem like I would have a reason to keep the bell housing in the factory location....and I like the idea of an additional inch of clearance between the engine and firewall/heaterbox.

Does anyone else have experience with using the standard (non-setback) plates?

 

[87National]

Anybody use the standard, non-setback plates? I want to be certain that I'm not overlooking something obvious.

 

[Kemper1976]

Anybody use the standard, non-setback plates? I want to be certain that I'm not overlooking something obvious.

I run the standard non setback plates in my 88. I was in a similar spot during my build because I had to have a driveshaft made and I could do whatever I needed to with the cross member.

I’m glad I went with the non setback setup. The trans bolts are easy to get to, I’m not fighting with the HVAC box. I do run power steering but I used the corvette accessories which keep the accessories closer to the motor. Zero clearance issues with anything including the oil pan.

Hope that helps.

 

[87National]

I run the standard non setback plates in my 88. I was in a similar spot during my build because I had to have a driveshaft made and I could do whatever I needed to with the cross member.

I’m glad I went with the non setback setup. The trans bolts are easy to get to, I’m not fighting with the HVAC box. I do run power steering but I used the corvette accessories which keep the accessories closer to the motor. Zero clearance issues with anything including the oil pan.

Hope that helps.

View attachment 133170

Thanks for the reply, that is exactly what I was looking for.

 

[Streetbu]

What headers/manifolds are you using with the non setback plates?

 

[Ribbedroof]

One negative if it matters to you is possible shifted frontal weight bias. Not sure how much lighter an LS is over a Gen1 SBC, might be enough to negate the forward shift although generally any weight removed from the front is perceived to be a positive change

 

[Kemper1976]

What headers/manifolds are you using with the non setback plates?

I’m running 2005 truck manIfolds flipped forward with Marman flanges, not V-bands.

 

[Streetbu]

I was hoping you had the Speed Engineering headers.

 

[Kemper1976]

I was hoping you had the Speed Engineering headers.

Sorry to disappoint

 

[Jimmy girl]

I used the Holley mounts . The whole kit actually. Car has Ac, and a whipple 2.9 that fits under the factory hood. If your not gonna use the Holley , I would use the standard so you can keep the ac