[David Cecil]

I bought a Unisteer Rack & pinion Kit for my 68 Vert. The Rack mounts behind the front crossmember using the 2 rear lower control arm bolts to bolt it to the car ,they supply 2 longer bolts for this .When I got ready to remove the old bolts, I wire brushed them and noticed they were grade 8.When I got the new hardware out, I also noticed the new longer bolts had 3 Marks and the letters JH on the head.
Correct me if I'm wrong but the rule of thumb for bolts is- Count the Marks and add 2 for the grade ie: 3 marks +2 = grade 5
6 Marks +2= Grade 8 which is how the OEM bolts were marked. I'm going to replace them with bolts I know are grade 8.I would suggest you all check yours and see if you have the same.I figured I better throw this out here ,because it's a saftey issue .Contacted Unisteer but they didn't get back to me
David

 

[pdq67]

How's the angle of the U-joint(s) for you??

pdq67

 

[David Cecil]

The angle seems fine you just have to understand out of phase means just that I'm not going to use the Nylon insert nuts that came with the kit either
only metal stop nuts should be used in the engine compartment where heat could be a factor they gave me Nylon nuts for both the control arm bolts and the tie rod ends once the nylon melts you might as well not have a nut on it.
GM used metal stop nuts for a reason
David

 

[davidpozzi]

Wise choices.
Be careful setting up your steering joints too.
David

 

[David Cecil]

This is an Update on the Unisteer issue.unisteer sent me a reply that they were looking into it???(Sounds like they aint looking to hard) So if any ones out there with a Rack & pinion By Unisteer CHECK YOUR CAR get rid of the grade 5 control arm bolts and the Nylon insert nuts for the Control arm bolts and the tierod ends!!!!!
the CA bolts should be metal stop nuts and the tierod ends should be castle nuts with cotter pins.The Neat thing about this is if the Control arm bolts don't break,the nylon will melt in the nuts. The rack could fall off and it won't matter if the bolts break.
Best David
68 Vert.350HO/TKO600

 

[David Cecil]

My last discussion with Unisteer was that they talked it over with the design Dept. and are not going to change from the Grade 5 bolts which are wrong or the nylon insert nuts Which sould not be used in the engine bay much less on a tie rod where they will move back and forth with out a Cotter key.So with that said I guess it's up to you the owner to know better.I just happen to have built 3 airplanes so I have a little better than average backround in bolt identification. Educate yourself enough to know whats wrong.YOUR FAMILY WILL RIDE IN WHAT YOU BUILT!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
With that said have a nice day David

 

[steeryourite]

David,
I appreciate your suggestions, but you are wrong. The grade 5 bolt is standard automotive grade. The grade 8 bolts you hade could have been changed by someone. Ive installed many of our kits and all the cars used grade 5. Id like to point out to you that we have a staff of real engineers here, we ISO and QS certified so decisions are always made with saftey being top priority. The answer that was given do you was, if you want to use grade 8 bolts then do so. Keep in mind that the control are bolts are in a rubber bushing. If anything would fail it would definately be the bushing first. In fact Ive seen many cross members(that are only 1/8" sheet metal) get wobbled out from worn bushings. Like I stated I appreciate your opinion.
Dave Batke
Unisteer Performance Products

 

[novaderrik]

both of my nova subframes had grade 8 bolts in the control arms. and they were definitely the stockers.
grade 5 might be "good enough", but the nyloc nuts on the tie rods? that just seems insane to me. every car i've ever seen has had a cotter pin in there to keep the tie rod nuts from backing off.
has the Unisteer stuff been DOT approved, and if not, i wonder what they would say about this?

honestly, how much more would it cost to upgrade to grade 8 bolts and cotter pins with castle nuts? a couple of bucks per kit?

 

[David Cecil]

It took me 4 hours to drive out the old bolts aint no way they had been replaced The new bolts ARE grade 8 on the lower front and I replaced the ones unisteer sent with grade 8 All I can tell you Mr.Batke is order a set from Rick's or Classic I bet they'll be grade 8 as for the Nyloc nuts.Accepted building practices are that you never use nylon insert nuts in an invironment where heat can be a factor rendering the insert useless. As for the tie rod ends why would you use a nylon insert nut on a bolt you know your going to take loose alot in the first few weeks of installation common pratice is you only use that nut once?Here's a little part of a book on Aircraft construction practices by the Late Tony Bingelis considered a Guru and builder of numerous aircraft

The self locking nut is most used by builders.It has a fiber/ nylon insert which limits its use to areas in the aircraft structure where temperatures do not exeed 250 degrees F.....otherwise the fiber locking insert may become brittle and deteriorate
An unused self-locking nut(nylon insert type) will have no threads cut into its insert,since that insert is elastic ,when the nut is torqued the fiber insert is forced tightly into the bolt threads and clamps the nut in place.
You can see that if the nut is used more that once this locking action may become progressively weaker as the elastic insert becomes treaded so I wouldn't reuse any self-locking nut (This would apply to the Contrl arm bolt and the tie rod)
Mr. batke I will agree that this is common building practice for Aircraft.I would also say that most on this net. would say don't take a chance with something as critical as the steering in the car
I can post Pictures of the Bolts I removed from the car ,as well as the OEM replacements and the ones you sent with the kit if you'd like?
As for the nuts? The OEM's were all metal? and don't you wonder why no OEM used a metal stop nut on a tie rod? Probably because they didn't want to burn it off with a torch after a few years. They used a Castle nut and a cotter pin Oh and as for your real engineers iso must stand for "In Search Of the coffee machine If you think for the first second that the engine bay on a car can't exeed 250 degrees in the summer then hope the "Engineers" will make better Lawyers Read up my friend.
Sorry Mr.Batke but your the one who's Wrong
David Cecil

 

[72Tugboat]

My '69 Bird had grade 8 bolts in the lower bushings as well as the knurled bolts (studs?) holding the upper cross shafts. I'm sure they were never changed.

If the engineers aren't aware of what the cars come with I have to wonder.

Good Luck!

 

[David Cecil]

OK just finished the install in the car if I had it to do over would have gone with another Rack Like Flaming River.I used new "Stover" nuts on the rear control arm bolts and Found out the tie rod ball stud shaft wouldn't go up in the steering arm enough to get into the nylon part of the nut Yea I cleaned the powder coat out of them ....so ditched those and went looking for something better.Closest I could come to ,wouldn't you know it was a 1995 Camaro. Taper is'nt right so went to the belt sander and using a Caliper got it down pretty close.Now I have a tie rod end with a Castle nut and cotter pin not to mention a grease fitting.Thank God Advance Auto see's fit to put the Spec's of TRW's tie rod ends on their website.All in all I think Unisteer's Rack kit is Very poorly engineered .The Rack should be Tilted back farther to align the shaft better. their lack of knowledge of established accepted industry building practice is nothing less than deplorable Concerning hardware included with the kit Oh don't forget if you go the route I did, Buff the Taper shaft after you sand it, could cause cracking if you don't
David

 

[davidpozzi]

David,
Everything you stated sounds good except the part about changing the tie rod end taper with a belt sander. That sounds scary to me.
You could have used "jet" nuts, or even low crown nylocs on the tie rod ends they supplied.

My 2004 SUV has no castle nuts on the tie rod ends or balljoints, they use the crimp nuts, all steel.
I remember my factory lower control arm bolts being grade 8, I'll check that out. a G8 bolt is aprox 20% stronger if I remember right. A grade 0 or 1 bolt is HALF as strong as a G5! I try to never buy grade 0 bolts, too dangerous to have around, they might find their way onto a car by accident.
David

 

[David Cecil]

David P.
I changed the Taper to fit the Steering arm Taper using a tie rod from a vehicle of comprable size and weight. We are only talking about 40 thousandth of an inch difference between the two. I would assume since the TRW tie rod was a little larger it is stronger and I checked my work with a digital caliper to make sure it was uniform. I could have done it on a lathe but Can't get it apart .If I could have found a sloted hex nut in 12MMx 1.75 course thread I would have used the ones from unisteer. So far I'm still looking ,find em in fine tread all day long .The threaded part of the unisteer tie rod didn't go up into the steering arm far enough to get into the nylon part of the nyloc nut so I would have had to go with a low profile nut.

Took the car out today for a trial run. First time I've had it out since I put in Tubular control arms,Rack&pinion,hotchkis sway bar,new 12 bolt rear and ,4 wheel disc brakes.It did fine, got it back up on the lift and checked the torque on everything(Tierods included)everything was where it was supposed to be. Was surprised I didn't have any issues with the U joints on the steering
David ,I'm confident that the Mod. to the tie rod will be fine. I used the sander because it doesent take material off like a grinder and can be easily polished when done
David Cecil
P.S If you do run across any 12mm slotted head nut in 1.75 course thread let me know!!!!!!!!!!LOL

 

[davidpozzi]

David,
You could probably make a castle nut out of a regular or nylock nut if you have a milling machine. Another thought is to just put the nylock on and drill through the nut and stud together then put the cotter pin in. Almost any nut would stay put if you put some red Loctite on the threads.
David

 

[David Cecil]

David,
I thought about drilling the nut and bolt together,might go that route at some point or mill myself a castle nut.I guess I could have asked unisteer what the tierod was designed to fit but at this point I'm pretty pissed off at them, as I'm sure they are at me.I wonder if anyone else had the same problem with the "Stickout" of the threads?
David since you know alot about the suspension in the camaro I just thought of a question?You said the Grade 8 bolt is about 20% stronger than a grade 5
but you must also remember that this bolt is resting on a little better than a 1/4" of steel at the front and back of each control arm bushing wouldn't you rather have the grade 8? considering that you have at rest about 750 Lbs. riding on those two 1/2" bolts
Anyway guys with the Internet I see no excuse for not educating yourselfs enough to know whats right and whats wrong. Most bolt manufacture's have information about identifying bolt grades on their website and like David Pozzi said No marks on the top of the bolts I wouldn't have em around
Thanks for the feed back David just send me a Bill-LOL
David Cecil

 

[David Cecil]

OK Guys,
Got some new info on the tie rod issue.Seems that GM used a standerd Taper for tie rod ends.That taper was 1 1/2" per foot,so with that I ordered a taper reamer to ream the steering arms.The arms will now take a standerd 95 Camaro tie rod end. Which will allow me to use Moog tie rod ends. The ends are much larger than the unisteer ends and have a grease fitting.The reamer comes from Ukut an American Co. if you need the part # i can get it for you
Have a Good One
David

 

[davidpozzi]

David,
I thought about drilling the nut and bolt together,might go that route at some point or mill myself a castle nut.I guess I could have asked unisteer what the tierod was designed to fit but at this point I'm pretty pissed off at them, as I'm sure they are at me.I wonder if anyone else had the same problem with the "Stickout" of the threads?
David since you know alot about the suspension in the camaro I just thought of a question?You said the Grade 8 bolt is about 20% stronger than a grade 5
but you must also remember that this bolt is resting on a little better than a 1/4" of steel at the front and back of each control arm bushing wouldn't you rather have the grade 8? considering that you have at rest about 750 Lbs. riding on those two 1/2" bolts
Anyway guys with the Internet I see no excuse for not educating yourselfs enough to know whats right and whats wrong. Most bolt manufacture's have information about identifying bolt grades on their website and like David Pozzi said No marks on the top of the bolts I wouldn't have em around
Thanks for the feed back David just send me a Bill-LOL
David Cecil

David,
I'd allways opt for the grade 8 bolts for suspension use.
Thanks for the Reamer info, how hard was it to ream the holes?

 

[David Cecil]

David P.
The reamer has'ent got here yet.I just ordered it but the folks at Ukut said it can be done with a Milling machine ,a Drill Press or, by hand using a Tap wrench.We're not talking about but just a few thousands of an inch so I might try it by hand rather than take the whole front end apart again.
I even got to drive the thing today set my toe in with one of those "Do it yourself guages" set the toe at 3/32, drives OK ,will be better after the front end shop sets the castor and camber. Speed tech called for 0 Camber,5 degrees pos castor
Had a car show here yesterday (Rural Virginia We still get excited about that)
Guy bought a 68 Z/28 new... sold it in 71... found it on the internet bought it back was digging through some old papers and found the protecto the build sheet and bill of sale from the dealer and the #'s match, still has the original 302! some guys have all the luck
David if you want the info on Ukut let me know The 1 1/2" reamer is about $60 Shipped and is made of M2 Steel or the better one is $72 and is coated the web site for Xkut sorry refered to it as Ukut is:
WWW.Xkut-reamers.com
David

 

[davidpozzi]

Thanks, I have both a 7 and 10 deg reamer I bought from Speedway Motors, but I haven't used them yet. They are fairly short and I'm not sure the small ends are small enough for stock sized tie rods.
David

 

[ls427ss]

DavidC...
I have to respectfully disagree with your branding Unisteer racks as being "unsafe" due to its suggested bolt strength, and I base that on the unit Flaming River received back from me @ 2:32 pm today for a full refund, because it IS clearly unsafe! Look at the pics below (if I am supposed to post photos in a different manner, will somebody please educate me) from my test fitting the Flaming River rack on my 67, and think about the environment it has been placed in, and the threat of instant severe damage from contact. Unisteers grade 5 bolts will never be in the same environment, or in any threat of damage from contact. Hell, look around... we all have cars that are in the weeds cause they look cool, and the only good point of Flaming Rivers setup is that it would probably save the bottom of a lot of headers, because it is lower and ahead of them. Check the pics and think about it... my intent is not to say you are wrong about being concerned with bolt strength or fastener type, but to open your eyes to something far far worse in design and safety that is thousands of times more likely to "cause an accident" just because you didn't see a dip in the road, a manhole cover sticking up, or something laying in the road.

For what it's worth, I ordered a Unisteer unit to replace the pos Flaming River, and even though I too will use grade 8 bolts and the safer fasteners like you... And you are also correct about adding 2 points to the marking on the bolts to determine the grade of the bolt... *grin*

This shows a side view of how far the "cradle" that bolts to the old steering box mount and idler arm mount and actually holds the rack, hangs below the crossmember (about 2") and would be the first thing to get torn off sporting a big block with a size 13 shoe...

This one shows about 20" of the cradle hanging below the crossmember from the front, you could use to remove any high spots of your choice, manholes, etc...

And here, we have 1 1/2" of the cradle that is supposed to fit flush and flat to the frame on both sides (2 sides each = 3") of stress you are going to put on the support for the rack after twisting it past its preformed mounting bends... ya think there would be an issue with fatigue on the bends or distorting it past the intended mounting position for the rack?


OK... now that we removed the steering from our pride & joy on a speed bump, how are we going to point it away from anything else that may bend up our baby because the steering rack is 500 yards behind us?

I realize, erring on the side of safety is very wise, and the right thing to do 100% of the time but remember, Engineers don't usually do bolts and nuts and base their learning's on technical "data" instead of field testing this stuff like we do, and enables us to know what works and what doesn't based on facts.

~Here are a few things about bolt grades, strength, and kind of interesting. There a lot of facts related to bolt strength, but you are right, grade 8 if you can, grade 5 is industry standard due to the difference in cost for several million bolts to manufacturers being more important than our safety~

Most people think a bolt is a bolt is a bolt. They see it as a machined chunk of metal that holds or attaches things. Fasteners (aka bolts or screws) are complex mechanically-engineered hardware. They are made using different materials, different thread types (i.e. coarse, fine, extra fine), various lengths, with grip or no grip (shank), different types (i.e. hex, 12 pt, carriage, etc.), different coatings (i.e. passivated, cadmium, dry film lube, etc.), various classes of fit (i.e. class 3), and multiple grades (i.e. grade 5, 8, etc.).
Bolts come with left or right hand threads, metric or SAE threads, different number of threads per inch (i.e. 20 or 28 for the same size fastener) and various versions of those (i.e. UNF versus UNJF). In addition, there are way too many military specs in existence to list them all here. So with all these differences, it’s no wonder most people don’t understand the difference between fasteners very well. Of all these differences, I’ll focus on the different grades since that is what most people ask about.
First, you need to be able to identify bolts by the different grades when you go to the local hardware store. Grade 5 bolts have 3 marks or lines on the head that are in the shape of a “Y”. Grade 8 bolts have 6 marks on the head.
Second, the different grades have a meaning to them. It tells you how strong the fastener is. There are different types of strengths listed for each grade. Proof strength (about 90% of yield), ultimate tensile strength (bolt fails in stretch), yield strength (bolt begins to get a permanent set and changes cross-sectional area typically) and shear strength (bolt prevents parts from separating by using it’s shank or body as a stop).

Depending on how you are using the fastener, you would look at the appropriate and corresponding strength type. For example, bolts that attach a D-ring bracket to the bumper face of a vehicle would be critical in tension . So you would want to know what the tensile strength a particular bolt is. Bolts that attach winch-mounting plates are typically seeing mostly shear loads thus preventing the winch from departing from the vehicle during winching operations. In that case, shear strength is important to you.
Mark’s Standard Handbook for Mechanical Engineers lists Grade 5 fasteners as 120 ksi fasteners. This means the tensile strength is 120,000 lbs per square inch. It also lists Grade 8’s as 150 ksi fasteners meaning the tensile strength is 150,000 lbs per square inch. Also, the ultimate shear strength of a fastener is typically about 60% of its ultimate tension strength. So given a certain diameter (cross-sectional area) and strength rating, someone can figure out how much load that fastener can carry in both tension and shear.

I’ve also heard the argument that grade 8’s are more brittle than grade 5’s and that’s why you shouldn’t use them. Well, first you need to understand what the term “brittle” really means. Brittleness in bolts is defined as failure at stresses apparently below the strength of the bolt material with little or no evidence of plastic deformation. Typically, fasteners are not brittle below 180 ksi ultimate tensile strength. Grade 5’s have an ultimate tensile strength of 120 ksi and a grade 8 fastener has an ultimate tensile strength of 150 ksi. This is why brittle is a relative term. Nearly all fasteners are considered ductile except some made from PH 15-6 Mo, 17-4 PH and 17-7 PH.

Grade 8 bolt capability in yield (stretch) = 130,000 lbs / in2 x .03349 in2 = 4354 lbs minimum

Grade 8 bolt capability in tension (failure) = 150,000 lbs / in2 x .03349 in2 = 5024 lbs minimum​

Grade 5 bolt capability in yield (stretch) = 92,000 lbs / in2 x .03349 in2 = 3081 lbs minimum​

Grade 5 bolt capability in tension (failure) = 120,000 lbs / in2 x .03349 in2 = 4019 lbs minimum​

Again, you can see that the grade 8 will support over 1000 lbs more or a 1/2-ton more. But there’s something more important to note. The grade 5 fastener has already reached its ultimate load and FAILED BEFORE the grade 8 starts to yield or stretch. Therefore, the argument that you should not use grade 8’s because they are more brittle than grade 5’s is not a true statement in most applications.
Toughness is an important feature of a fastener. It is the opposite of brittleness and gives you an idea of how it will handle abuse without being damaged and eventually weakening the fastener or can cause fatigue to appear much earlier than normal. One way to “measure” toughness is by looking at the hardness rating of a fastener. The higher the number (Brinell, Rockwell …) the harder the material is and the tougher it is to damage. According to Marks’ Standard Handbook for Mechanical Engineers, Grade 5’s typically have a core Rockwell hardness of C25-C34 whereas a grade 8 typically has a core Rockwell hardness of C33-C39. Based on this, grade 8’s are tougher than grade 5’s.
Fatigue usually doesn’t play a big part in grade 8 or grade 5 fasteners since most steels are good for 2 million to 10 million cycles. Far more than you will ever winch or pull on. Here is a quick point about fastener fatigue. Almost all fastener fatigue failures are the result of improper (almost always too low) torque. Too low a torque will cause the fastener to pick up more load more often and eventually cycle it to failure. Therefore, you want to make sure you torque your fasteners to the appropriate level using a torque wrench and make sure to torque dry, clean threads. Lubricated threads significantly change the actual preload on the fastener and you risk over torquing it.​