I have an 86 base model no sunroof ,sound deadner removed,ac removed the car is light and tight accept its been hit ! I also have an S5 gxl clean interior clean body its just sooo heavy ! the motor is bad inthe S5 so i was considering puttin my hot motor and all my after mkt. gear on the S5 but can i get the weight down to that of my S4 ?? the S4 hood is aluminum the S5 steel (no brainer) does anyone have a weigh in list ? i will post factory door label weights later
MY OBJECT IS TO MAKE THE S5 LIGHT AS POSSIBLE or if it does not come clse i will stick w/s4 i think the difference is about 500 lbs. !!
Thanx_Dino

 

it's not worth the hassle of redoing the dash harness and repining almost all of them to make a S4 motor work in a S5.

series swaps are never worth the trouble even though it was a T2 motor unless you're going w/ a fuel controller like a haltech or microtech EMS.

 

Non turbo to non turbo, the weight difference is usually around just less than 200 lbs (not 500lbs) between series.

and there have been dozens of posts to why.

But mostly it is trim and bolt on stuff.

Like S5 has a bigger gas tank, heavier carpet, more insulation, extra bars in the dash for safety, extra metal in the A and B pillars for the mouse belts, dumb stuff like a steel jack instead of the uberlichet german aluminum jacks on the S4 models or steel spares instead of aluminum ones...

Stuff like that.

 

I would go with the short block the only issue should be swapping the omp. 200 lbs do you think its possible to bridge that gap I haven't seen any threads that tackle weight reduction.

 

Then you have not looked very well.

and less than 200 lbs... on some models only around 125 lbs difference between series.

For example 88 GTU to a 89 GTU or GTUs model- only about 125 lbs

 

you are probably correct in that asumption however the s4 is a bare bones base model and the s5 is a gxl as i mentioned before im diggin for more info anything you can share is much appreciated

 

Well (as posted countless times before)these are the main weight differences between a S5 and a S4:

1.Bigger gas tank (not sure if you would want to change this)
2.Heavier parts for the extras like tools, jack and spare (you would need to use S4 ones for less weight)
3. Extra metal to re-enforce dash because of the SRS/Mouse belts (not a whole lot you can do about this unless you take out the S5 dash metal and use a S4 one instead)
4. Extra metal on the A piller, and B piller to support the mouse belt system and extra metal in roof to support the mouse belts. (again, nothing you can do about this without cutting apart the unibody).
5. Heavier carpet (thicker nap)(you would want to use the carpet from a 86-87 S4 base or sport model if you wanted the lightest carpet kit).
6. Increased sound suppression (you would have to remove all the tar paper and padding under the carpet and cloth on the doors, and use a S4 carpet as mentioned above)
7. Options made standard (like power mirrors) (well you would have to use non power mirrors from a S4 for the lightest)
8. Front bumper support (only about 5lbs difference, and I don't know if a S5 bumper will be supported correctly without a S5 bumper support).
9. Intake and VDI (use the lighter S4 ones, but give up peak HP doing that)
10. alum hood would save you about 20 lbs as the alum hood was only on the convertibles and the S5 GTUs (not the GTU) on the S5 models, while you found the alum hood intermittently on quite a few S4 models besides the convertibles.
11. sunroof, most S5 models (except the GTUs model) came with a sunroof, but you would have to swap roofs or find a body without a sunroof to save that weight

 

I'm going to buy a scale and I reckon I will keep the S5, its a much more asthetic car but I gotta get it at its fightin weight . Thanx icemark im gonna keep diggin for more info. Anybody on the same path or been down the same path?