# L47/Aurora 4.0L powered Fiero. **URL:** \ **Category:** Builds\ **Created:** [March 9, 2016, 10:37pm UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686 "2016-03-09T22:37:30Z")\ **Posts on this page:** 20\ **Page:** 5
**Author:** ![Shifty](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/shifty/32/4959_2.png) [@Shifty](https://forums.speedlife.net/u/Shifty)\ **Post date:** [July 13, 2016, 12:02pm UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/81 "2016-07-13T12:02:43Z")
> [@L47](#): > > Oh, word? Alright. I’m going to run over to the shop in a bit anyway, so I’ll grab my calipers and I can get you some drawings in a couple of hours. There are four out of twenty that have ‘dowel pin’ shoulders machined into them that go into the top corners or each bank to help locate the heads. If I were going to do through the trouble, could I have you make me like four of each of two designs? They’re not drastically different. I’d just like to have spares lying around just in case. I’m paranoid. I pm’d you my # ---
**Author:** ![1QIKZ](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/1qikz/32/6112_2.png) [@1QIKZ](https://forums.speedlife.net/u/1QIKZ)\ **Post date:** [July 13, 2016, 12:16pm UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/82 "2016-07-13T12:16:15Z")
> [@Shifty](#): > > I can have these done, PM me the specs. Make sure you send them to him US Postal box. ---
**Author:** ![ubengineering](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/ubengineering/32/5171_2.png) [@ubengineering](https://forums.speedlife.net/u/ubengineering)\ **Post date:** [July 13, 2016, 1:01pm UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/83 "2016-07-13T13:01:59Z")
Well if Newman can’t do it you’re screwed, scrap the whole project lol sucks you have to wait though. ---
**Author:** ![L47](https://avatars.discourse-cdn.com/v4/letter/l/db5fbb/32.png) [@L47](https://forums.speedlife.net/u/L47)\ **Post date:** [July 13, 2016, 7:29pm UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/84 "2016-07-13T19:29:31Z")
> [@ubengineering](#): > > Well if Newman can’t do it you’re screwed, scrap the whole project lol That was my thought, too. Then Shifty slides in and potentially saves the day. I sent him some chicken scratches I scrawled out earlier and he said he’ll get to me tomorrow with a lead time and cost. Fucking perfect. That’s how it should be done. Anyway, I dicked around with the intake some more. At this point, I can probably have the car fully reassembled the same day as stud delivery, or the next if that’s late. Doesn’t look like this week though. Oh well. I’m used to getting kicked in the nuts with this thing. Hopefully soon, anyway. ---
**Author:** ![Norb\_O](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/norb_o/32/5189_2.png) [@Norb\_O](https://forums.speedlife.net/u/Norb_O)\ **Post date:** [July 14, 2016, 5:04am UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/85 "2016-07-14T05:04:05Z")
Clean up and paint the intake manifold while it’s still out. It’s a shame to put all that effort into those rails and have them bolted to a dirty plastic manifold ---
**Author:** ![L47](https://avatars.discourse-cdn.com/v4/letter/l/db5fbb/32.png) [@L47](https://forums.speedlife.net/u/L47)\ **Post date:** [July 14, 2016, 7:24am UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/86 "2016-07-14T07:24:17Z")
> [@Norb O](#): > > Clean up and paint the intake manifold while it’s still out. It’s a shame to put all that effort into those rails and have them bolted to a dirty plastic manifold Good point. You’re not the first to mention it. I would try hydro dipping it, but I just feel like that would get crazy busy visually. Suppose I could just do a fresh coat of black to clean it up. Maybe shave some of those unnecessary plastic from it, really clean it up. Not doing much else today without that stud. ---
**Author:** ![Norb\_O](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/norb_o/32/5189_2.png) [@Norb\_O](https://forums.speedlife.net/u/Norb_O)\ **Post date:** [July 14, 2016, 7:55am UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/87 "2016-07-14T07:55:59Z")
Anything with a gloss clear coat, regardless of color, will be far easier to clean and will make the engine bay “pop” like you wouldn’t believe. Don’t need fancy hydrodip. ---
**Author:** ![maxwell](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/maxwell/32/6524_2.png) [@maxwell](https://forums.speedlife.net/u/maxwell)\ **Post date:** [July 14, 2016, 8:09am UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/88 "2016-07-14T08:09:05Z")
First thought is black… but red would work, too… ---
**Author:** ![Quattro\_Krant](https://avatars.discourse-cdn.com/v4/letter/q/ac91a4/32.png) [@Quattro\_Krant](https://forums.speedlife.net/u/Quattro_Krant)\ **Post date:** [July 14, 2016, 9:02am UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/89 "2016-07-14T09:02:32Z")
Gray ---
**Author:** ![L47](https://avatars.discourse-cdn.com/v4/letter/l/db5fbb/32.png) [@L47](https://forums.speedlife.net/u/L47)\ **Post date:** [July 14, 2016, 9:26am UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/90 "2016-07-14T09:26:03Z")
> [@Quattro Krant](#): > > Gray I like this idea, actually. For some strange reason. I just think gray would be rad. Either that or black. Definitely not red. Too much red already, with the valve/cam covers and MSD coils. I think this is why I like the gray. I saw it on a FAST LS manifold once or twice. Satin gray would be pretty awesome. Stud guy got back to me today and told me he would get my ‘as fast as possible’ package out today. So maybe I’ll have that tomorrow or Saturday? Here’s to hoping I can salvage the rest of my vacation. Having said that, I’m going to go clean up my intake manifold. Hah. ---
**Author:** ![ultradriver10000](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/ultradriver10000/32/7397_2.png) [@ultradriver10000](https://forums.speedlife.net/u/ultradriver10000)\ **Post date:** [July 14, 2016, 9:30am UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/91 "2016-07-14T09:30:21Z")
Post up some better pictures of the stud, both failed ends. It doesn’t really look like it failed torsionally, normally there is a nice smooth twist you can see in the structure. Almost looks like some meteorological failure with those pocket looking spots in it. I know rolled threads are stronger, but a precision cut tread on this one guy shouldn’t be an issue if it came to it. What is the torque spec on these guys? ---
**Author:** ![maxwell](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/maxwell/32/6524_2.png) [@maxwell](https://forums.speedlife.net/u/maxwell)\ **Post date:** [July 14, 2016, 9:32am UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/92 "2016-07-14T09:32:59Z")
Yep, nevermind… Gray. ---
**Author:** ![JayS](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/jays/32/15375_2.png) [@JayS](https://forums.speedlife.net/u/JayS)\ **Post date:** [July 14, 2016, 9:53am UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/93 "2016-07-14T09:53:29Z")
That gray with your fuel rails would look great. ---
**Author:** ![L47](https://avatars.discourse-cdn.com/v4/letter/l/db5fbb/32.png) [@L47](https://forums.speedlife.net/u/L47)\ **Post date:** [July 14, 2016, 9:54am UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/94 "2016-07-14T09:54:09Z")
> [@ultradriver10000](#): > > Post up some better pictures of the stud, both failed ends. It doesn’t really look like it failed torsionally, normally there is a nice smooth twist you can see in the structure. Almost looks like some meteorological failure with those pocket looking spots in it. > > I know rolled threads are stronger, but a precision cut tread on this one guy shouldn’t be an issue if it came to it. What is the torque spec on these guys? I think the stud started stretching after the 60 pound pass. It never got any tougher to turn and snapped shortly after. I’m fairly certain it was a metallurgical failure, but I can’t say for sure since I’m not a metallurgist. If you look at these pictures, you can definitely see the stretch. It’s like a 30 degree taper down to the failure point from the start of the threads. It looks like there was almost a weak spot. I can’t get better pictures with my shitty phone camera, but the threads actually started to pull away form the body. Strange. Torque spec is only 75 ft/lb. Nothing crazy. First pass is 30 pounds, second is 60 pounds and a final pass at 75 pounds. A torque wrench only measures rotational force about the fastener, so I can’t tell you what the actual clamp load is or what the real-life tension is on the stud once torqued. I’ve got a good 3/8" click-type Craftsman torque wrench that I’ve had zero problems with over the last few years, so I don’t think there’s any issue there. I’m sort of just scratching my head. Must have been a bad stud…? ---
**Author:** ![ultradriver10000](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/ultradriver10000/32/7397_2.png) [@ultradriver10000](https://forums.speedlife.net/u/ultradriver10000)\ **Post date:** [July 14, 2016, 12:01pm UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/95 "2016-07-14T12:01:04Z")
Stud was bad, you’ll see the threads pull away like that because they are stronger, being work hardened by being rolled. I’m surprised they didn’t give you a torque angle spec for these. The resultant torque from the factory was about ~105nm or 77 ft lbs FYI. I’d call the guy and tell him the stud was bad and ask him to overnight you a replacement. The only way the stud could fail like this and have good metallurgical properties is if the friction on the joint was extremely low (like non-existent). Even then I wouldn’t expect a bolt of this size to fail at such a low torque. ---
**Author:** ![L47](https://avatars.discourse-cdn.com/v4/letter/l/db5fbb/32.png) [@L47](https://forums.speedlife.net/u/L47)\ **Post date:** [July 14, 2016, 4:02pm UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/96 "2016-07-14T16:02:14Z")
Fair enough. That’s definitely what I suspected. At the end of the day, I did the exact same thing to 19 other studs without issue, so I had my suspicions that something was weird with that one. He messaged me thus morning and said my package would go out this morning, but I haven’t heard back so who knows? I must have told him ten times to overnight it. Hope he did. Anyway, I cleaned up that intake manifold. Check it. Before: ![http://www.clutchsuperclutch.com/images/fieropics/IMG_20160714_143735.jpg](http://www.clutchsuperclutch.com/images/fieropics/IMG_20160714_143735.jpg) Halfway shaved, which was a real pain in the dick: ![http://www.clutchsuperclutch.com/images/fieropics/IMG_20160714_152615.jpg](http://www.clutchsuperclutch.com/images/fieropics/IMG_20160714_152615.jpg) Much better: ![http://www.clutchsuperclutch.com/images/fieropics/IMG_20160714_182403.jpg](http://www.clutchsuperclutch.com/images/fieropics/IMG_20160714_182403.jpg) Great idea, fellas. I should get my GPS speedometer tomorrow, so hopefully I can get that in. Here’s to hoping my stud shows up tomorrow or Saturday. ---
**Author:** ![maxwell](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/maxwell/32/6524_2.png) [@maxwell](https://forums.speedlife.net/u/maxwell)\ **Post date:** [July 14, 2016, 4:07pm UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/97 "2016-07-14T16:07:17Z")
I’ll say a prayer to the car gods for ya. Love this thread. Keep it coming. ---
**Author:** ![Akursed](https://avatars.discourse-cdn.com/v4/letter/a/c67d28/32.png) [@Akursed](https://forums.speedlife.net/u/Akursed)\ **Post date:** [July 14, 2016, 4:12pm UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/98 "2016-07-14T16:12:11Z")
As a previous owner of a 3800-turbo Fiero, I hope you have some positive vibes coming your way and can get this car on the road. Good stuff! ---
**Author:** ![L47](https://avatars.discourse-cdn.com/v4/letter/l/db5fbb/32.png) [@L47](https://forums.speedlife.net/u/L47)\ **Post date:** [July 14, 2016, 4:35pm UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/99 "2016-07-14T16:35:43Z")
Thanks, guys. I’m just so close and it keeps kicking me in the nuts. Pretty sure this car is cursed. Hah. ---
**Author:** ![Norb\_O](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/norb_o/32/5189_2.png) [@Norb\_O](https://forums.speedlife.net/u/Norb_O)\ **Post date:** [July 15, 2016, 4:51am UTC](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686/100 "2016-07-15T04:51:16Z")
got studs bro? [Previous page](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686.md?page=4) [Next page](https://forums.speedlife.net/t/l47-aurora-4-0l-powered-fiero/273686.md?page=6)