regarding your back bumper, its because you lost the laminar air flow once the air reached the end of the splitter. Once the air starts tumbling and becomes turbulent it is very hard to get back laminar again. hence why your diffuser/ panel at the back wouldnt have done much. and why diffusers in general have very little effect unless paired with a flat floor.

 

In a round about way yes haha. I just mean its not like the manufacturer is out there to make their car more aerodynamic for performance/speed e.g like what a widebody kit or big wing would do but for fuel efficiency.

 

 

Kyle engineers is my bible love how he breaks everything down in plain language. some of his inteviews of designers of cars like RP968 is amazing too

 

But his drawing skills leave something to be desired

 

Aero is aero.

We do it for increased speed. The increased speed is due to reduced drag. The OEM wants reduced drag for efficiency.

 

So joy of joys... Ive had a seized subframe bolt for about 2 years. Its the vertical bolt that goes up through the control arm and the nut is in the frame rail. I had been able to get it tight "enough" and just left it. But I found it it just wasnt clamping all that great this winter.

So I drilled a small hole in the chassis to spray some PB Blaster (its what I had...) and tried to work it for a couple days. But eventually I snapped it off. YAAAAYYYY!

Ok, maybe I can drill it enough to break it out. Made a guide to try and get a drill centered but it walked as you'd expect. And I snapped the drill bit in the bolt. So that options out. YAAAAYYYY!

Current idea - The hole is 17mm and the tip of the screw is 24mm deep. So Im going to machine a 17mm OD, 14x1.5 tapped inner, and ~23-24mm long. I'll thread it on a bolt and push it up in there. Then weld around the base to lock it in. That should work right? Ugh...

If it doesn't, my buddy is a wizard with fixing these kinds of things and if we have to we can cut a window, cut out the threaded sleeve thing, and weld a flange nut in there.

 

Oof those are the worst. Being a midwesterner and commonly dealing with stuff like this all my chassis and suspension bolts go back in with anti seize.

As long as the threads are secure in the chassis then your idea should work. Would bug the hell out of my OCD to have one subframe bolt be noticeably shorter than the rest lol.

If you have access to the weld nut they're normally not too hard to break loose with a decent size drift and a hammer.

 

yikes. We had those get stuck in two cars.

if you haven’t tried it before Aerokroil is THE BEST penetrating oil I’ve ever used.

the tt car started lift as a 212k mile car from Montana. Put it on the lift and sprayed every suspension bolt once a day for a week or so. everything but the one bolt you had problems with came out.

we had to keep staying that one for a few more days but finally got it out.

 

I dont think it was a rust issue in this case. We dont really have rust here and no other bolt has any signs of it. What I think happened is I probably used that bolt for alignment on the subframe and persuaded it into place. I think it took a burr of metal or something up with it and then reversing it bound up and everything just seized. Cause I could move the bolt but only about 1/4 turn at first till it got smaller and smaller.

 

Oooofffff. Galled up bolts like that situation are the worst. They won't even come out with drilling and an EZ-out.

 

Yeah, was not impressed when I found it. I dealt with this a ton on old DSM turbo bolts but never in the chassis.

 

 

I cant think of exactly which nut it is your talking about. we had one of the power steering pump nuts break loose inside the subframe and we had to holesaw a hole on the lower side to get some vice grips on it and get it out. Being the one thru the control arm i guess you probably dont have an option like this. Doing a plug like your suggesting would be the best way to do it and just weld it in. other option would be rivnut possibly but i dont think id trust it for a suspension bolt

 

this bastard. That one's a lot more difficult than the captive bolt one. oof that's rough.