Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Technical BBS > 1- Porsche Technical Forums > Porsche 911 Technical Forum

Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by afterburn 549 View Post
If he had not pointed some stuff out i would have missed it..
It is interisting.
However I find the projected HP on the anemic side..12 cyl !?Ought to be way up there
Thanks afterburn. I was told by someone with two engine experience that the engines would produce 400 hp and double the torque but it doesn't matter to me. I won't be trying to break any records. Just have fun.
Old 10-15-2017, 03:09 PM
  Pelican Parts Technical Article Directory    Reply With Quote #61 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by porsche930dude View Post
If it stays together by then. check out those bugger welds! thats a shame
Are you a welder? Are you a 917 expert? Do you know what is a weak and a strong weld? Do you know How this was welded? Do you know what Replicating something means.

Go here to get educated on 917 welds. https://www.youtube.com/watch?v=f3rbNkhL0Sg&t=531s

After welding the chassis I spent 3 days adding more material to make the welds look like 1969 Porsche 917 aluminum Gusseted welds. If you put this chassis into a car crusher, every tube would be bent and not One weld would be broken.

Jack
Old 10-15-2017, 03:16 PM
  Pelican Parts Technical Article Directory    Reply With Quote #62 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by javadog View Post
I'm not one to normally knock aguy when he has invested this much time into something but that's a textbook example of what not to do when building a space frame. Odd, given that there's so much information available on how to do it right and he could always have simply copied the original design, if he didn't want to design something from scratch.

The rebar was a nice touch.

JR
Javadog Do you know one of the definitions of a fool? It's a person who opens their mouth to comment on something they know nothing about.

I created an almost exact copy of a 917 chassis allowing for the suspension and drivetrain I used. I even made the ONLY 12 cylinder boxer engine in a 917 replica.

The rebar makes you chuckle? You can buy more expensive ones at places like Summit Racing. They are for setting the car at the desired ride height to measure for coil overs.
Old 10-15-2017, 03:22 PM
  Pelican Parts Technical Article Directory    Reply With Quote #63 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by TRE Cup View Post
Bravo! this guy is showing some real ingenuity. I think you can get well over 300 hp per
Subie reliably, when the turbos are set= just about where the original turbo panzers started in Can Am.
He is smart in mocking things up with pvc, cardboard tubing, etc , so he can see how it will all work together
The rebar is used to set ride heights, before installing the coil overs. I hope he keeps at this project and gets it all dialed in. Its going to be quite a ride

Good luck
Now here is one of the few commenters that has achieved a level of maturity that their mother's would be proud of.

Thanks,

Jack
Old 10-15-2017, 03:25 PM
  Pelican Parts Technical Article Directory    Reply With Quote #64 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by JohnJL View Post
"My next project is going to be a Tyrrell 6-wheel Formua 1 car for the street"
Now that I have gotten my Second Wind and this project is close to completion, I probably will do the 6 wheeler. I have designed it a couple of different ways but I will probably build it so I can order a set of Tyrrell P34 tires from Avon. It won't be for the street however. It is so small a Civic would run it over.

Jack
Old 10-15-2017, 03:28 PM
  Pelican Parts Technical Article Directory    Reply With Quote #65 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by haycait911 View Post
yeah, the rest of it isn't terrible, but those welds are nasty and kind of drag the rest of it down.
Go read my comment to him and learn about 917 welds here. https://www.youtube.com/watch?v=f3rbNkhL0Sg&t=531s

The rest of the car "Isn't terrible"? Would you please post photos and videos of the car YOU built from scratch?

Jack

Last edited by Jack2052; 10-15-2017 at 03:31 PM..
Old 10-15-2017, 03:29 PM
  Pelican Parts Technical Article Directory    Reply With Quote #66 (permalink)
 
Now Available for Ordering:   101 Projects For Your BMW 3 Series 1982-2000  [more info]
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by j911brick View Post
At least you can see the forest in spite of the trees. I think some people are being over critical of this guy's work. He actually has some good ideas like the Corvette suspension and twin subi motors, which is pretty close to what factory did originally.
Thanks,

Jack
Old 10-15-2017, 03:33 PM
  Pelican Parts Technical Article Directory    Reply With Quote #67 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by afterburn 549 View Post
It looks better then my 917 LOL
To be truth full "pipe" or "tube" is tricky to weld at 1st till you get used to it...as long as they are not "cold welds" he will be fine....Most the time those are ground dwn to look pretty..maybe he will get to it.
I say we give him a "A"
Thanks afterburn Actually I spent three days making the welds look like 917 welds.

https://www.youtube.com/watch?v=f3rbNkhL0Sg&t=531s
Old 10-15-2017, 03:35 PM
  Pelican Parts Technical Article Directory    Reply With Quote #68 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by redturbo911 View Post
No matter how you look at it that guy did some nice work.
Thanks redturbo.

Jack
Old 10-15-2017, 03:36 PM
  Pelican Parts Technical Article Directory    Reply With Quote #69 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by brads911sc View Post
most of the people on this board couldnt build/weld/fabricate/design something like that... why all the negativity... not my cup of tea but that is alot of work and is well done.
You're Right and Thanks brad. The loudest negative commenters are the ones who haven't done more than a 1:24 scale plastic model.

Jack
Old 10-15-2017, 03:38 PM
  Pelican Parts Technical Article Directory    Reply With Quote #70 (permalink)
Porsche Nut
 
merbesfield's Avatar
 
Join Date: Mar 2009
Posts: 797
Garage
Please don't let a few rotten eggs spoil it for all of us. Please continue to post your build. I love it.
__________________
'68 912 #12820385
'66 Toyota Land Cruiser FJ45
'71 Olds 442 Convertible
'79 MB 450SL
The Garage
Old 10-15-2017, 03:57 PM
  Pelican Parts Technical Article Directory    Reply With Quote #71 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by 911Freak View Post
He commented on the welds in the first video stating they were made to look like that to in his words "emulate the ugly welds on the original 917 frames".....

There is a lot of mock up going on with what you are seeing, try to give this guy a chance to complete the vision and engineering.

I give him props for effort for sure.

BUT I have to wonder if there wasn't a better "model" to copy, surely he could have used plans-drawings-blueprints as opposed to copying a model? What if that model he copied was missing a few key structural points? Is he trusting his life to a 'made in China' model?

I bet it will end up pretty damn cool (already is) and close to resembling the real thing...not sure if it'll perform and stay in one piece, but the guy clearly owns a tuner shop for corvette and ricers so he has the capability to pull this off...

Overall thumbs up and A for effort!!
Thanks 911freak. I think this is the place I will set a lot of guessers straight.

1. I spent 3 days making the welds look like the 917 welds. https://www.youtube.com/watch?v=f3rbNkhL0Sg&t=531s

2. "Mock Up" like the rear upper control arm brackets so I could calculate coil over length and weigh the car as well as many other uses.

3. The model was Only used to measure the dimensions from the roll bar to the front and rear axles. All other information I got from photos. I had to Design and Engineer the chassis around the drivetrain and suspension. It also had to be designed for maintenance of the systems without having to disassemble the car. Spark plugs, oil filters etc.

4. When I started this project I searched the internet looking for all the information I could find and couldn't find anything close to structural drawings.

5. This chassis is way stiffer than the original and Well Engineered! You could put the chassis in a crusher and not one of the welds would break.

6. A Tuner? a Shop? I spent my life in construction building new houses, had a restoration business for 10 years and supervised commercial construction for 18 years. These cars are the First I have done and the only time I worked on cars I striped threads and broke bolts. I built these cars and an airplane in a one car space in my three car garage.

I just woke up one morning at 4 am and said, "I'm going to build a car!

Old 10-15-2017, 04:00 PM
  Pelican Parts Technical Article Directory    Reply With Quote #72 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by afterburn 549 View Post
wonder what it will way? 1500>?
I weighed it once but now I would guess 2200 Ibs.

Jack
Old 10-15-2017, 04:06 PM
  Pelican Parts Technical Article Directory    Reply With Quote #73 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by Bob Kontak View Post
Can't argue with that. The weight of those bars has to be tremendous. Additionally, they could bend with arm strength in a vise vs. tubes. Maybe the rebar was post budget constraints??? Note the entire frame of the 917 weighed under 100 pounds. Those bars alone have to weigh 15+ pounds.

Have to keep it all in perspective. The guy is a "regular guy" and although an odd undertaking, I am really, really impressed with his huevos - maybe a better word is adventure-som-ness (I just made that up) to take on such a project. My hat is off to him.
Thanks Bob. It was more like a dream than having anything to do with big huevos. I just woke up one morning at 4am and said, "I'm going to build a car."
Old 10-15-2017, 04:09 PM
  Pelican Parts Technical Article Directory    Reply With Quote #74 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by afterburn 549 View Post
Why do you say that? (about the 50MPH)
I think he is doing great, just not done...a lot of mock up still there.
If those frame parts were proper prepped for welding so as to get a good root pass they will hold no mater how ugly
Not ugly, accurate!
Old 10-15-2017, 04:12 PM
  Pelican Parts Technical Article Directory    Reply With Quote #75 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by javadog View Post
It's not the welds that worry me, although I'd like to know what type and size of tubing he used. You can't really judge any of that from the videos. It's how it's all constructed; how the tubes are laid out and how the loads are fed into the chassis.

Have a look at a Porsche space frame (or any similar race car frame from that era) and study the joints, the triangulation, etc.

JR
java Don't worry, the tubes, welds and design you could bet your mothers life on.

Jack
Old 10-15-2017, 04:16 PM
  Pelican Parts Technical Article Directory    Reply With Quote #76 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by jluetjen View Post
True. Building replica like that shouldn't be a whole lot more difficult than building FF. After I posted the original videos, my biggest concern is if the car would really be track-worthy. The way that he has a few things struck me as not being able to pass scrutineering. But that may be because it's still a work in process.

Either way, my hat's off to the guy for getting the project this far along.
Yes, a work in Progress. The term you're looking for is Mocked Up!

Thanks,

Jack
Old 10-15-2017, 04:18 PM
  Pelican Parts Technical Article Directory    Reply With Quote #77 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by GWN7 View Post
That looks like David & Vicki's car. If that is it, the shell is a actual factory 917 body.
Wish I knew where the 917/10 body store was when I was ready to start My body!

Jack
Old 10-15-2017, 04:20 PM
  Pelican Parts Technical Article Directory    Reply With Quote #78 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by javadog View Post
Tubes are intended to be loaded in tension and compression. You don't want to introduce a bending load into them, mid-span. A space frame is sort of a connect-the-dots type of design. First you locate critical points, like the the suspension pivot points in this case. Then, you lay out the tubes in such a way as to transfer whatever force are present at these points into the main structure. You don't build the frame first, without looking at the loads that will be imposed upon it, and where, then attach the suspension at whatever point it happens to fall.

JR
Can you spell Mocked Up?

Jack
Old 10-15-2017, 04:22 PM
  Pelican Parts Technical Article Directory    Reply With Quote #79 (permalink)
Registered User
 
Join Date: Feb 2012
Posts: 73
Quote:
Originally Posted by jluetjen View Post
oh -- I see what you mean.



That is particularly nasty. Like you pointed out there are loads being introduced mid-span on that tube and the tube in front of it. The way that he did this is bad for 3 reasons

1) The trailing arm of the a-arm will get compression loads going through it during acceleration, and more importantly during cornering, and there is nothing behind that point to take these compression loads. To a lesser degree there will be tension loads on that point during braking.

2) Even nastier is that he attached the bracket holding the a-arm pivots by a bolt through the tube. So right there he's taken away at least a 3rd of the tube's strength by drilling a hole in it. He's also compromised the tube by putting compression forces on the diameter of the tube, which can cause the tube to flatten after the bolt is tightened, weakening the tube even more.

3) If you are going to attach something by bolting it, the bolt needs to be in double-sheer, or in extreme situations single-sheer with a larger bolt.

If he tries to drive that car in anger, it's quite likely that those tubes holding the rear suspension will fail, with potentially catastrophic consequences if it occurs at speed. If you look at this picture of a real 917/10's rear suspension you can see that the rear upper "a-arm" is really a trailing link from the bulkhead which is loaded in compression/tension under acceleration and braking, and a lateral link that goes to a mount at a junction of tubes (although it is not real clear in the image) that handles the lateral loads.



Here's a close up from what I think is a 906 chassis of where the lateral link ties into a frame bracket. The point in question is in the center of the image. I'm pretty sure that the execution was pretty much the same on all of Porsche's tube-frame chassis prototype chassis.



Note how it is boxed in, and tied to the "bulkhead" tube in the background that goes to the other side of the chassis. Also note that the bolt through the lateral link's rod-end is supported on both-ends of the rod-end by the bracket. While not perfect or elegant, it's a far superior design.
When you EDUCATE yourself to what My intentions are, at what STAGE the car is at and know Something about a 917, then you May be able to carry on an Intelligent And Mature conversation about My hard work. Until then, remember what your Mother told you. "If you have nothing nice to say, don't say anything at all."

Did it make you feel good to show everyone how smart you are? All you showed me is how Immature and Insecure you are.

Jack
Old 10-15-2017, 04:28 PM
  Pelican Parts Technical Article Directory    Reply With Quote #80 (permalink)
Reply

Thread Tools
Rate This Thread
Rate This Thread:

 


All times are GMT -8. The time now is 09:52 PM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2016 Pelican Parts - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.