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Alponcho
05-11-2025, 09:17 AM
Hi all. After 3.5 years, about finished with a 79 Trans Am project with my son. It's a real Y84 car with no t-tops (originally 403 auto), and was completely stripped and disassembled when we bought it. He was in HS at the time and mini-tubbed it himself. We're running a stroked LQ4, Terminator X Max (thanks Andrew), TXK, 9" 3.25, full Ridetech coilover set-up, etc.

The only problem we're dealing with is ground clearance, and the main culprit is the stainless Hooker long tubes (LS Swap for 70-74 second generation f body). The driver's sider hangs lower by about .75". We're using Holley mounts & crossmember. Anyways, we're considering switching out the headers to mid-length or shorty's, and wondering what option would be best from a clearance/fitment standpoint? Not opposed to Speed Engineering if they work well.

As an aside, I had custom headers made for my Pontiac Powered '70, but that was a very expensive proposition, and even those hang too low given where we live.

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Vimes
05-11-2025, 03:44 PM
Assuming the Holley mounts are either nonadjustable or adjusted to their highest setting, I think I'd try stacking some washers underneath the engine mount to get the header up a bit. About a quarter inch at the mount should get you that 3/4 inch at the header outlet. You might have to put them all between the car and mount, between the engine and mount, or stack one or two on both.

Once you figure out how high it needs to be to clear, you'll need to clearance everything else to make sure something else isn't out of place. And, if everything works out you'll want to replace the washers with a steel plate cut out to the shape of the engine mount before driving. I'd be concerned about just washers allowing enough twist to crack the mounting points but a solid plate of steel sandwiched in won't allow the twist.

This solution might work for both cars, too.

79 Camaro
05-11-2025, 04:33 PM
My current LS swap is a 80 Camaro with a LS3/4L60E.
I used Speed Engineering 1.75" headers. They are even with the bottom of the sub frame not below. I used non adjustable LS engine mounts. Stock 80 Camaro frame/engine mounts.
I know the SE headers are China made but I've used them on a couple other LS swaps with zero issues.
Couple of pics.217172217173[ATTACH=CONFIG]

woody80z28
05-11-2025, 05:29 PM
Beautiful car(s). I used china stainless shorty headers on my Beretta LS swap and I'd do it again in a heartbeat...unreal how nice they are for $92. For my SBC 80 Camaro I had to cut the driver tubes to get the clearance I needed. The length you'll need to take out to get the clearance you need is a guess, so sneak up on it. It's also different tube to tube depending on how different the angles are. But that turned out to be a really nice solution for me.

Alponcho
05-12-2025, 06:36 AM
My current LS swap is a 80 Camaro with a LS3/4L60E.
I used Speed Engineering 1.75" headers. They are even with the bottom of the sub frame not below. I used non adjustable LS engine mounts. Stock 80 Camaro frame/engine mounts.
I know the SE headers are China made but I've used them on a couple other LS swaps with zero issues.
Couple of pics.217172217173[ATTACH=CONFIG]

Thanks! 1.75 full length headers? What brand mounts?

Josh@Ridetech
05-12-2025, 09:00 AM
I used the Ultimate Headers longtubes on my '79 with Hooker engine mounts and they were dead even with the bottom of the subframe. They were great.

79 Camaro
05-12-2025, 12:25 PM
Engine bracket wise just the "standard" LS non adjustable that have only one set of tapped holes for the rubber engine mounts. Sorry no great pics except this one of the 80.217185

Alponcho
05-13-2025, 06:56 AM
I used the Ultimate Headers longtubes on my '79 with Hooker engine mounts and they were dead even with the bottom of the subframe. They were great.

Thanks for the reply. These headers seem like a good option. Did you use their Extreme Low Profile Clamps as well, and if so, do you have to weld them on the header and install bungs for oxygen sensor? Do you have any pics you can share of these installed? I see the dimensions on line but missing the width up top. Thanks in advance.

79 Camaro
05-14-2025, 12:53 PM
Just an FYI. The SE headers have the ox sensor welded into the collector on both headers. I did have to dimple the floor plans about 3/8" to clear the ox sensor.
I don't typically use the welded band clamps because I'm cheap. LOL.
I buy 3" OD to 2.5" reducers and use the 1" wide band clamps like they use on late model car/trucks. I slot the 3" reducer so the reducer really clamps down on the collector. I add muffler cement just to make sure no leaks.

Josh@Ridetech
05-15-2025, 05:32 AM
Thanks for the reply. These headers seem like a good option. Did you use their Extreme Low Profile Clamps as well, and if so, do you have to weld them on the header and install bungs for oxygen sensor? Do you have any pics you can share of these installed? I see the dimensions on line but missing the width up top. Thanks in advance.

They're the best fitting pieces that I've ever used. I did use their low profile clamps (they welded the flange for that on the header for me and then I just had to weld the other side to the mid-pipe. I did have them leave out the O2 sensor bung and welded it in after I got them mocked up to make sure I had everything positioned right, just to be safe. I have a picture of them off the car right now, I'll try to find one with them installed as well. They were perfect.


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Alponcho
05-15-2025, 03:27 PM
They're the best fitting pieces that I've ever used. I did use their low profile clamps (they welded the flange for that on the header for me and then I just had to weld the other side to the mid-pipe. I did have them leave out the O2 sensor bung and welded it in after I got them mocked up to make sure I had everything positioned right, just to be safe. I have a picture of them off the car right now, I'll try to find one with them installed as well. They were perfect.

Thanks for the info, Josh. I spoke with Jim today and ordered a set. Should be here mid July.

On a related note, we've been having some issues dialing in the ride height in the front, and looking for advice. We bought the Ridetech full coilover set up in early '22, right before the change over. So, the kit came with a tall spindle, tall upper ball joint, and regular lower ball joint. I've tried the 3.6" travel shock & 8 inch spring, which I have to crank all the way up to even have a finger between the tire and fender (and impossible for me to crank up without an extension on the coilover tool). Also tried the 4.1 travel shock and 10" spring, which even at the lowest sitting gives me way too much gap (like 2"). Is there a set-up that would put me right in the middle?

Josh@Ridetech
05-16-2025, 04:49 AM
The 3.6 w/ the 2.75" stud is standard on that kit and really what should be used to keep the control arms in the proper geometry. This shock configuration is in it's happy place right at 12.75" from center of lower bolt up to the hole in the shock tower. The 4.1 shock isn't going to allow you to achieve the ride height you want, the control arms will also bind up on the balljoints before the shock tops out so it's not really a good route. The balljoints you're seeing are correct. Out of the box, it is common and normal to crank the spanner nut that high on this setup (we set it up this way actually). The Hyperco springs we use are a linear rate coil spring so the spring rate is going to stay whatever rate it is, no matter how much it is compressed. By using these springs, we can run a lighter rate spring and achieve a better ride quality. This one is a common call for us (alot of guys think they need a higher spring rate to have less preload but all they'll get with this is a stiffer ride and use a little less preload). Don't be afraid to crank the nut all the way up to the top if you have to. I ran 650's on this car cranked all the way to the top to put the shock at 12.5" (I ran mine a little lower because I liked the look) and it was great to drive :cheers:

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andrewb70
05-16-2025, 07:14 AM
Hi all. After 3.5 years, about finished with a 79 Trans Am project with my son. It's a real Y84 car with no t-tops (originally 403 auto), and was completely stripped and disassembled when we bought it. He was in HS at the time and mini-tubbed it himself. We're running a stroked LQ4, Terminator X Max (thanks Andrew), TXK, 9" 3.25, full Ridetech coilover set-up, etc.

The only problem we're dealing with is ground clearance, and the main culprit is the stainless Hooker long tubes (LS Swap for 70-74 second generation f body). The driver's sider hangs lower by about .75". We're using Holley mounts & crossmember. Anyways, we're considering switching out the headers to mid-length or shorty's, and wondering what option would be best from a clearance/fitment standpoint? Not opposed to Speed Engineering if they work well.

As an aside, I had custom headers made for my Pontiac Powered '70, but that was a very expensive proposition, and even those hang too low given where we live.

217170217171

That looks great!

Andrew

carter_eng_fab
05-19-2025, 11:32 AM
That's one sharp TA! Definitely need a shot from the rear. I have 285's on mine but I really want to cut and mini tub it.

What's the box on the drivers inner fender?

Alponcho
05-20-2025, 06:49 AM
Here you go Carter. We'll paint or pc the exhaust pipes black when we switch out the headers.

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Josh@Ridetech
05-20-2025, 07:25 AM
What's the box on the drivers inner fender?

Those are the covers for the fuses he's using in his battery cables/wiring. :cheers:

Alponcho
05-20-2025, 08:01 AM
Yep, those are AAW's mega fuse holders. Not pretty sitting there, but functional and a very convenient location.

As you suggested Josh, we cranked up the coilover nut to about 2 threads from the top and ride height is perfect now, so all is good there. Looking forward to the arrival of the Ultimate headers, and our next tuning session with Andrew.

Here are a couple shots of the car when we picked it up Nov 2021. It was a stalled project, already stripped and completely rust free. We'll probably finish off the interior this week (carpet, door panels & seatbelts). Still have to fab a base and some stanchions for the shaker. After that, charge the AC, alignment, sand and buff (we did single stage), install grills and headlight bezels...then the full Y84 decal treatment.

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