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My project car is taking a LONG time. Baby steps here and there. The next few steps are the expensive ones, so I'm kind of at a standstill for now. However, I'm always looking for ways to improve this or that. I was looking into some type of functional heat extraction as my car will be somewhere along the lines of pro-touring and it will more than likely see plenty of track days if all goes well. LORD willing. Heat extracting hood vents and louvers are not an option for my hood. But fender vents? I checked it out and figured I could make it work. So I decided to do something small and functional to satiate my craving for some progress. I ordered this set of fender vents from a late 70's early 80's Trans Am off of ebay.
These areas of my engine bay would need to be cut to allow the air to flow out to the vents. The passenger side is pretty clear, but the driver side has more clutter due to all the brake equipment. Plus the firewall is more forward, closer to the wheel well/strut tower. But it is still enough room to function.
I started as soon as they arrived, cleaning them off and altering them. As you can see, I cut the opening slightly larger.
I had some extra aluminum mesh that I used for my front grille and hood opening, so I decided to use that so it can all match.
I marked the opening size with a sharpie andcut out the shape to match with pliers. It cut really easy and clean.
Then I* test fit it over the opening.
After a few more alterations around the edges, I cleaned, sanded, primed and painted the fender vents. Now they were ready for the mesh to go on. I used JB Weld to secure them.
And let them cure for 24 hours with a little bit of weight on them.
After I cut the driver side inside (no pics of that) I saw that there was some frame in the way. I had to remove the fender and cut away some of that. Here is what it looked like when I removed the fender.
And here is what it looked like after I made the necessary cuts.
Next, I made a template of the shape that would go into the fender.
With the fender back on, I set the template on the fender and lined it up where the vent would look and function best.
I marked it with a silver sharpie where I would need to cut.
I had to do a few more minor cuts and shaving to get the vent in place but it fit almost perfectly. Here it is from a few different angles, in place, but not secured. I will have to do that from the inside with some hardware that I will have to make or improvise.
Here are the views from the engine bay. Very functional, but not too clean. I eventually want to fabricate some type of duct that points directly to the vent so nothing is blowing all over between the fender and the body.
And here is the view from the outside looking in.
Well this, coupled with my hood, will allow for very functional cooling. Cool, fresh air blowing in through the hood opening, passing over the intake and headers, flowing all that hot air out of the back corners and out of the fender vents.
I haven't done the passenger side yet but it is a similar process. It may be easier to do than the driver side. I'll get around to it soon but for now, I'm very pleased with the result.
This project took me about 3 days total. One day for alterations, sanding, priming and paint. One day for the JB Weld to cure. And one other day of cutting, which actually only took about 4 or so hours. And the cost was around $100 or so. The vents were like $80 and the Dremel discs that I used for the cuts were $20. JB Weld was like $5. And I already had the paint and grille mesh.
I'm open to feedback and questions. I hope this helps if anyone decides to try it. And I can't wait till she's running and I get to see how these work!
It looks cool from the outside, but I have similar thoughts to what Twin_Turbo said. I understand you had to cut out the frame to make them work, but it this is going to be used as a track car you really should consider welding some reinforcements in around where you cut.
i imagine you could beef up the cut sections easily enough.
hope you report back eventually with some results.
very creative and they dont look bad at all. good job.
Yeah, Dont listen to the nay sayers. Most of the best things in this world were invented while having someone saying it cant be done or what have you. You could easily weld supports or rig something up to support the weakened areas if they are in fact weakened. Only thing that came to thought when I saw it is wonder if it would have looked better/what have you if you switched sides with the vents. I know its too late now, but I think it may of looked better with the body lines if the vent you installed on the drivers side was on the pass side....? idk... just a thought. Great job and keep on keeping on.
Cosmetic is only a small reason as to why I did it. FUNCTIONALITY as I said multiple times throughout the post was my main goal. Ya, I cut out a small section of the frame, but the majority of it is still there. I suppose I could weld a small bracket around the bottom of where I cut. There's plenty of room in the fender for that.
And my project car, like I said, is VERY pro-touring oriented. I'm not overlooking any aspect. It will have a 3 point strut tower brace and weld in subframe connectors. All suspension components are brand new. Front has BMR coil overs with KYB struts, tubular K member and A arms, and Wilwood disc brakes. I'm not worried about such a small section of fender frame messing with the structural integrity of my baby. Get real.
I'm not worried about such a small section of fender frame messing with the structural integrity of my baby. Get real.
In actuality that section of the frame is what actually holds the car up. By cutting that much out of it you actually risk the car bending at that point, not to mention the implications if you had an accident. My car was wrecked, I only found out after I took the front sheet off, and my rails are still mostly in-tact, but they are bent. If that large a piece was cut out, the car would not have survived.
It's not only how much you cut out, but the location.
This is not a small matter as you're suggesting. I would not hit the street until you reinforce that.
I'm really hoping that you will rethink your position on whether or not cutting out a huge chunk of the front frame rail was a good idea. The jury is still out on whether or not coil overs (on our cars) are good idea because it moves the entire weight load of the front from the stock stronger area to the strut mount of the strut arch. So in stock form most of the weight is going to the lower and inner frame rail via the spring and then secondarily to the top outer frame rail via the strut. So again, with coil overs you have moved most of the front end's weight to the top outer frame rails which you have now hacked up, and you've hacked it up in the worst way. The force that that frame rail will see will be vertical so it needs the most strength (ie material) in the vertical aspect, which is the exact area that you removed. Nobody on here knows for sure what the effect of what you did will be, but we can surmise that you just weakened your cars chassis. The way to correct this is going to be to either cage the front end or or weld in a round tube at a 45* angle from just in front of where you cut to as low as you can go on the pillar/firewall area. Then also add a bar perpendicular to the welded in bar that goes from the center or so of the welded in bar to just behind where you cut out.
For this instance, that's not good advice. TwinTurbo is very smart and helpful when it comes to these cars. RedNeckJoe is really good too and his threads show he has some abilities. The three of us could really help him with this.
Well I do appreciate everyone's input. Like I said, it shouldn't be a problem to weld a brace around that. I will before ever taking it out. This is, as I said, a long, slow project. Probably won't see a street for quite some time. I have enough time to learn how to weld and do it myself before this is ever running. So thanks for the advice. I will eventually weld it up and throw some pics of how it turned out. My advice to some in return is, give advice and criticism in a more constructive manner. We're all brothers here with the same common interests. Or, at least we should be.
Cool idea , both functionally and cosmetically, but I'm afraid I have to pile on and say you have underestimated how critical those rails are to the chassis integrity.
Remember this isn't a frame car, those rails aren't just holding the fenders in place, they are supporting the front of the unibody.
Hers a pic of the unibody stripped, see how those rails form one corner of a torsion box frame.
It's been a little while but I'm back. I finished the passenger side too. I took some pictures and made marks to show where the cut is. Now I'm not completely convinced that the portion I cut is a major structural piece. The sub frame below the strut tower has way more metal and it's squared. The section I cut was pitifully thin and easy to bend. However, I agree that it may have weakened the front slightly, and I also agree that it would be best to weld in some reinforcements.
Here is the passenger side before the cuts. The red lines are where it needed to be cut, and it's not a lot.
The rest of the pictures are of the driver side. Same exact stuff, but I have more room to work and take pics there. Now, the original piece of frame was triangular but narrow. This should give an idea of how...
I am going to weld in some steel DOM tubing like this...
That is the plan. The tubing in the picture is not what I will be using. I am going with 3/4" - 1" x 0.12 steel tubing. Smaller diameter, but much thicker wall. Once it is welded in, it will give it even more secure structural integrity than the original. It will then have a much larger triangular shaped brace with 5 points of reinforcement like so.
I wonder how many people have looked at this thread, and understand that they'd be wasting their breath explaining why this is a really REALLY bad idea.
I wonder how many people have looked at this thread, and understand that they'd be wasting their breath explaining why this is a really REALLY bad idea.
How thick is the lid of a shoe box. How strong in twist is the box with the lid compared to without it. Strength doesnt necessarily come from thickness. It can also be a compound shape.... think corrugated cardboard.
Last edited by Twin_Turbo; 09-20-2017 at 01:04 PM.
The subframe is the primary support for the vehicle. The section I cut is part of a brace, not major frame. It is a thin piece of stamped steel and I only cut a small section of the flat side. I did not cut through the angle of the brace so it still retains the majority of its rigidity. I have already acknowledged that any cutting will be a weak spot, but I am not leaving it. I am welding in steel tubing. The same tubing that is used for a roll cage. It will be welded behind the cut, along the cut, in front of the cut, and will have three additional sections welded in a triangular brace along the solid portion of the firewall frame. Nothing is being overlooked. This section will be STRONGER than it was before. I don't understand how you think this is "a REALLY bad idea." I made cuts to allow for a vent which will keep my engine bay cooler and reduce the air and lift under the hood thereby aiding in downforce. Two positive benefits. I am welding in the bigger and stronger brace in a larger triangular pattern along the fire wall frame which will improve the rigidity of that section. Another positive benefit. The engine bay will have a 3 point strut tower brace for even more stability. That's another positive benefit. The car will have weld in subframe connectors. Benefit. It will also have a tunnel mounted torque arm with the transmission crossmember welded in. All benefits that increase the rigidity and support of the frame. Do you think that people who tube frame the front of their cars have "totally messed up" their frame? Or compromised the front of their car? Take a look at this guy. He completely cut that section out entirely and only has 1 steel tube coming off the firewall and has it welded to the subframe.
This guy too has done something similar.
And most people see this as an improvement.
I appreciate constructive feedback. We are all here because we are 3rd gen enthusiasts who want to make our vehicles better. We learn from each other and improve. If you have helpful feedback, leave it. If you don't like the project, that's fine too. If you hate it and only want to criticize it, then don't post anything. Take that drama starting nonsense over to Facebook where it belongs.
I am reading this thread for the second time and I feel the need to chime in. 85ProjectZ28, I think the idea for the project is a good one, if it will accomplish what you set out to do. I do feel that given the amount of structure you have taken away from the car, you should consult with a mechanical or design engineer (reputable) before you start welding in bracing that may or may not add the strength you are looking for or necessarily need. Every facet of a vehicle is designed to withstand the forces caused by speed, acceleration, gravity, etc. and the body is no different. I have been in the design world for over 30 years and if it were my project. I would get some kind of professional direction before going any further. Your safety, and the safety of others, rides on the integrity of your build.
But, enough said from my end... I like the idea, I think the vents look great, but I think there can be a lot said for some better implementation. Good luck, 85ProjectZ28, and carry on!
I'm open to feedback and questions. I hope this helps if anyone decides to try it. And I can't wait till she's running and I get to see how these work!
Just so everyone is clear here - he's only open to GOOD feedback and POSITIVE questions. If anyone thinks that shock absorbed type thing with the springy thing on it is going to fold his front end in half when he takes a hard turn - go find him on Facebook and tell him there.
It's clear the OP hasn't bothered to think about how his coil over conversion has moved all the spring stress from the front crossmember's spring pockets to the strut towers. Or how the strut towers are a bit of a weak link to begin with, and nearly all of the support for the strut towers comes from the frame rail he cut away. His lack of understanding is further evident in his illustrated proposed bracing, and comparing that bracing to a tubular chassis.
The above isn't intended to help the OP, he's on his own. It's for the benefit of any poor soul who may be tempted to follow in the OP's footsteps.
You know, it's all good. I'm not going to stress. Post whatever feedback you want. I'm good. I love my car and I'm excited about all I have done to it so far, and look forward to all I still have to do. She's going to be amazing when she's done! Fast, clean, efficient, powerful, sleek, capable, unique, and best of all, completely done by me. My ONLY regret is that I can't have her finished now and start showing the world what we are capable of.
Thanks everyone for all your input. It has all been a big help. I'll continue to document this project until it's completion.
Last edited by 85projectZ28; 09-20-2017 at 10:37 PM.
Reason: Pic
You could have just cut the fenders for the vent/s.With the "windows" in the frame rail/s & the vents directly in front of said windows, combined with the low pressure effect it would've been enough to "suck" the heat out.All w/ out needing to cut your car.
I consider this constructive criticism, btw.Not negative in any way.
Not trying to knock you down bud but I have to say it, you drive it enough and you're car will have the shape of a banana. What you cut out even though it is thin sheet metal had a purpose. When sheet metal is stamped or formed on a press break it grows tremendously in strength, you cut that out. It served the same exact purpose as the tubes running parallel with the frames in the pics you posted. For the safety of yourself and others let someone with structural knowledge and fabrication experience help you correct this.
THis thread was brought to my attention by a few people asking me to chime in because of my chassis dynamics specialty.
What you have done is extremely dangerous enough even if you do not have coilover. The fact you do have coilovers and have distributed the load of the complete front half of the vehicle onto the strut towers and have sacrificed the vertical tension section of this critical suspension location point is catastrophic. Unless you run a caged tubular frame section boxed from a cockpit cage inside the drivers area forward to the front of the lower subframe rails (Like the picture you listed of the white car) you will not have any boxed structure location to keep the top and bottom half of the car from failing and killing yourself AND others.
If and when this happens the investigation will lead to you altering the vehicle from DOT standards and you will be placed in prison for years. on involuntary manslaughter.
This will fail...period. You cut the main upper chassis support and quadrupled the load onto it.
I think being held criminally responsible is a stretch but I'm in the medical world, not the legal world. What I can say is I've scanned many people for serious neck and back injuries resulting from a motor vehicle accident and $100,000 is usually gone in the first year. I scanned a guy last wet who said the $300,000 he got from the other driver was gone in five years. Your vehicle's insurance liability protections will become null and void if an insurance company found out ex post facto that the accident was caused by you altering the chassis. I'd get that car to a chassis shop as soon as you have the money.
With any automobile death the law requires an automatic investigation as to how and why the accident happened. So-
Penalties for Car Accidents
A driver who causes a car accident may face civil and criminal penalties, depending on the circumstances. Accidents caused by a driver’s negligence, such as failing to look before backing out of a parking stall, reaching for something that fell off the seat, or failing to reduce speed when the road is wet, commonly subject the driver to civil penalties, when the other driver files a civil lawsuit.
A driver who causes an accident by breaking certain traffic laws, or when driving under the influence, may face criminal charges. Penalties for conviction of criminal charges may include arrest, fines, jail or prison time, and a suspended license. If another person dies as a result of the accident, the accused driver may be charged with vehicular manslaughter, or involuntary manslaughter, which carry harsher penalties.
In addition to criminal prosecution, such a driver will likely face a civil lawsuit as well. The victim of a car accident can file a civil lawsuit seeking damages for loss of property, injuries, loss of earnings, and more. If the victim died as a result of the accident, his family can file a civil lawsuit for wrongful death. This allows a surviving family member sue the at-fault driver to receive compensation.
I too just stumbled across this post...I like the aesthetics of the vent idea, but yea, agree he may have compromised the front structure. For years I've always wanted to install the trans am vents on a Camaro. Anybody here ever done it?
I'm not into splicing pig and elephant DNA. But maybe, just for cosmetic purposes, late second gen Z28 fender vents might be a little less out of place on a thirdgen Z28?
Or maybe a louvered second gen Z28 style fender vent below the body line, like a thirdgen Trans Am? Idk, still seems like something from the peel and stick aisle at Vato Zone.
So you guys want an update? Here’s the update.
All the work on my car is completed. I put the engine in and got her running early 2023.
Now for the fender vents.
I did weld in some reinforcements on the sections of the frame that I cut.
The car has a 3-point strut tower brace and it is solid. Weld-in subframe connectors make the car even more solid.
I built this for autocross/time attack and that is exactly what she does best.
It did pass tech inspection with no issues.
I have raced it multiple times and driven it VERY HARD and VERY FAST. She performs flawlessly.
No, the frame hasn’t crumpled or folded like a banana.
This car turns like it is on rails.
The fender vents work. I raced her all day in 90 degree weather and she never went above 200.
She has never had any issues driving under any conditions thus far.
Now to all the nay-sayers and trolls, especially DREW, I’d like to give a solid F U. You have nothing better to do than troll my posts and talk trash? Moderators, I find it funny how he can joke about saying that I died, but I’ll probably get banned for this response.
I’m certainly not dead. In fact, I’m living life to the fullest. My car is amazing. And every bit of detail has its purpose. I built this entire car, by myself, in my 2-car garage, with only the help of books and some other, more helpful people on forums. Absolutely no thanks to ****** like DREW or any of the clowns that sided with him. Crack jokes all you want. In the end, the only joke is you. My results speak for themselves.
My car looks better than anything you have. My interior is cleaner. My engine bay is cleaner. My undercarriage is cleaner. I’ve raced and I’ve won. My car is featured in a 2024 calendar, and she gets waves, thumbs up, pictures taken, and compliments everywhere she goes.
Talk all the trash you want. I’ve already won.
And in case anyone is wondering, this is personal.
11-06-2016, 10:54 AM
