Agreed - but it allowed me to use large hardened M8 bolts and just do it via tapping. I weighed them before and after milling and 38% of the material is removed. All together with the bolts each weighs 1lb-1oz, so like 3.25lbs for all.I think you could probably reduce the 3/4" place by half and get the same structural benefit from them.
make the exxe do a wheelie
On the replacement trunk lower floor? Yeah, that was the attempt. That was some of my earliest work - learned a LOT since then. In retrospect I would have got a bead roller but not sure it's worth it at this point. That floor gets heavily painted then coated below and insulated, finally covered on both sides (lower has the aluminum cap with insulation, upper has insulation and false floor).
The weld beads attempted to shrink the metal... sorta works.
Finished the engine bay stiffening tonight. As this is a K20 swap and expecting a little bit more torque than the stock unit, some care needs to be given to upgrading the attachment points for the powertrain.
On a K20 swap (MWB) the subframe attaches to the rear suspension pickup points in addition to the existing engine mount. Under acceleration, the engine wants to rotate backwards (opposite tires) and the engine mounts stop it from doin so, thus trying to make the exxe do a wheelie or go forward. All the stress on the rear cross mount is "pull" under acceleration.
In the MWB kit they do tell you to reinforce this cross member - their suggestion is adding a very thick bar. I chose instead to add a 14g plate to the rear side of the cross member (in the exhaust area) and otherwise just stitch weld up the joints. To further strengthen the cross member, I fabbed up a stress member from the lower to the mid/upper cross member. Similar to the 'spare tire cover' plate I did, I added a piece of aluminium with M6 bolts thru into weld nuts. This should make for a stressed member cover plate for engine access.
(NOTE: my '76 didn't originally have an access panel from the trunk to the engine like later models do ['79+ I think] but it is so useful I wanted to add it).
Anyways, here some pics of the work. I put on some high zinc primer on areas.
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Darin, everytime I see the title of your thread I think of these guys and start singing in my head (perhaps an intentional move on your part):
Finished the engine bay stiffening tonight. As this is a K20 swap and expecting a little bit more torque than the stock unit, some care needs to be given to upgrading the attachment points for the powertrain.
On a K20 swap (MWB) the subframe attaches to the rear suspension pickup points in addition to the existing engine mount. Under acceleration, the engine wants to rotate backwards (opposite tires) and the engine mounts stop it from doin so, thus trying to make the exxe do a wheelie or go forward. All the stress on the rear cross mount is "pull" under acceleration.
Did you also consider the K24? Trying to find out what if any differences it makes in terms of the install. Are you using the MWB frame kit?
I went with the K20a2 (K20 is a JDM only thing) as is revs higher than the K24 thus more "exxe" in my opinion. Horsepower (200) and torque (142) and redline (7400) are well above what I had with the 1300 or 1500. I'm not even having any performance mods done to the engine, at least not yet.
I am using the MWB kit. I'm not positive about the difference in height from K20a2 to K24 - maybe Tim (fiatmonkey) knows but I read somewhere it's like 2cm taller. I think they're otherwise very close. You'd need to verify the ECM/Hondada setup for some of the later model K24s and if you're serious, I'd recommend you give Matt or Brayden at MWB a call as they might know.
I think your car looks rad BTW and deserves a hot drivetrain to match the looks