View Full Version : Looking For ST-7 Cage Pictures

08-30-2007, 09:35 PM
Hey Guys, It seems as if there are quite a few of those in here whom are racing in EMRA. Ive been poking around getting involved with my 76 when it's done instead of SCCA. I have a local in town who does tons of work for me and is willing to barter with me for his services in building me a cage. (I must say his work is quite impressive) Nevertheless this would be his first Spridget cage and I'd like to see what others are running so I can point him in the right direction. And tips, do's, don'ts, or pictures would be great! Thanks Guys.

08-31-2007, 04:54 AM
Funny your should ask...I'm just finished building a cage. But for my ST-4 Escort.

The number one best way is to show up at one of our events and bring a camera, tape measure and take notes. That's what I'd really recommend.

Anyway, for my Spridget, I'm not that crazy about the own cage since it's sort of cobbled together from an existing roll bar.It's safe, but sort of clunky.

But I also drive a Sprite (#23) owned by my friend Pete, and I like his cage. He built it a few years ago. It should be at Pocono on Sept 8.
Keep in mind that you must use DOM tube (not ERW) and for a Spridget it should be 1-1/2 inches nominal OD. You can get away with 0.090" wall, but I'd use 0.125" because we're all just amateurs and have to get to our regular jobs on Monday morning....a little more protection can't hurt.

Mounting to chassis can be bolted (5/16" bolts that are Grade 5 minimum). Mounting plates should be 3/16" thick. You can also weld it in, but it can be a challenge to weld thin, unibody stamped steel to 3/16" plate. Most of the amateur jobs I see don't look great.....I'd prefer bolt-in unless your welder is a real artist.

Pete's car has a horizontal bar that goes from the right side halo bar to the middle of the dash. He has a switch panel mounted on it. I'd skip that part. He also has bars to the front shock mount area that stiffens the car...not a bad idea. My car is a rubber bumper chassis and has similar stamped steel members in that area.

Sitting in the car normally, you need 2" above the helmet for the overall cage. The rear part of Pete's cage is high. Pete and I don't need the extra height, but he built it with our pal Bruce in mind (Bruce is like 6'3").

Be sure to have a good shoulder belt mount. It's best exactly at shoulder lever and not too far back behind the seat (2" to 4" is good if you can do it). Generally, this is a horizontal bar that the shoulder belts loop around, but you can also weld plates to bolt the harness mounts to it.
Also, try to keep in mind an upper seat mount (for the seat back), since that's required for most seats.

A horizontal bar behind the dash connecting the two front down tubes is a good idea too.

You can bolt or weld the door shut but if you do, it can be a pain fixing thngs. #23 has it's oil filter and alternator in the right side passenger area, so the doors open and close for easy service.

And check the EMRA Car Prep guide (similar to SCCA).


Some of the other guys may want to chime in...that lots of ways to do this.

Here's pictures of Pete's car....this is all I have on hand.








08-31-2007, 10:37 AM
Nice pictures. Love the 'Midnight Auto Supply'

08-31-2007, 11:06 AM
I took these for a friend caging his car. You can see in picture 262 that there is a single door car that has was cut out when the nascar bars were installed. The outer bar on the right side is just bolted in to pick up the door panel. I have plans to remove it and reinstall a hinged door.


08-31-2007, 01:59 PM
Nial, what does DOM stand for/mean?

08-31-2007, 03:35 PM
<u>D</u>rawn <u>O</u>ver <u>M</u>andrel, as opposed to ERW, which is just <u>E</u>lectrically <u>R</u>esistance <u>W</u>elded tubing.
ERW has an ugly weld seam on the ID, which can be a potential failure area. DOM, while welded, is drawn over a mandrel, smoothing that area, and stress relieving the tube.

08-31-2007, 03:37 PM
DOM= Drawn Over Mandrel Tubing. That Much I do Know. It's the requirement for both SCCA and EMRA. I Believe they still make ERW tubing cages for NHRA. But not around here anymore.

Guys Thank You for these great pictures. I hope to run into some of you up at Lime Rock in October. Unfortuantally I will be sending the car in for it's cage in two weeks so I won't get to see any of these up close but this guy makes some really impressive stuff. I'm sure if I point him in the right direction I can Expect greatness. Am using 1.5 X 0.125 DOM as I see that in most Spridgets. I spoke with Pete a few weeks ago and was even considering schleping this tub over to jersy to have 'em fab me a cage but the price and timing couln't be better. Thanks Guys for all the great input.

09-01-2007, 06:54 AM
One last comment concerning Spridgets that I almost forgot.

You will notice that the halo bar (over the driver's head) on Pete's car is fixed to the "shelf" area in his car (actually, part of the inner fenders on his car...you can see it in the 3rd picture).
In my car, it's fixed to the "floor" in the area of the forward leaf spring mounts. I believe Chis's halo bar is mounted to the floor too.

There are two schools of thought on this, but basically, both methods are fine.
Mounting on the shelf area gives you a bit more freedom with the seat mounting, so I would probably do it that way if I was starting from scratch. But if you mount to the shelf, try to use a fairly large base plate to spread the load out.

09-01-2007, 09:21 AM
One more thing to keep in mind, the SCCA now requires double door bars on both drivers and passenger sides. You should go to the SCCA website and download the new cage regulations. Take those along to the cage builder.

09-01-2007, 11:46 AM
I had noticed those differences Thanks Nial. Will you be at Lime Rock in Oct?

09-02-2007, 07:28 AM
I believe Chis's halo bar is mounted to the floor too.
The main hoop or halo on my car is mounted to the front of the parcel shelf just behind the bulkhead. There are reinforcing plates welded to the front spring hanger area, up the bulkhead and on top of the parcel shelf. The main hoop is then welded to that. There are also braces from the main hoop back to the wheel wells, again with reinforcing plates.

09-02-2007, 09:00 AM
Build the cage per the SCCA GCR and your car will be legal to race in all organizations (vintage, SCCA, EMRA, etc).

09-02-2007, 12:02 PM
Build the cage per the SCCA GCR and your car will be legal to race in all organizations (vintage, SCCA, EMRA, etc).

EMRA Car Prep rules (link in my first post above) are the same as SCCA for cages struture.
We did it that way on purpose.

09-03-2007, 10:59 AM
That is my intention. So I could reace in others later on if so desired.

Hap Waldrop
09-04-2007, 12:52 PM
Here's a couple pictures of the cage we did in my FP car.

09-04-2007, 05:40 PM
Now that is impressive. I do like the cage in the Blue / Yellow HP car on your website.

Hap Waldrop
09-05-2007, 07:17 AM
Now that is impressive. I do like the cage in the Blue / Yellow HP car on your website.

I thought I would share the picture with the rest of the crowd.

09-06-2007, 01:43 PM
Very Nice indeed. I hope you don't mind I showed this pic to my local shop and said "Make me This!"

09-06-2007, 01:45 PM
Very Nice indeed. I hope you don't mind I showed this pic to my local shop and said "Make me This!"

I'm gonna need your assitance on an MGB Su to bolt up to a 1500 Manifold (Similar to Nial's #11) This winter. I'm Planning to run this engine I have til I can get a nice 1275 put together.

Hap Waldrop
09-08-2007, 03:32 PM
Sure go ahead on the cage design, you're welcome to copy it.

As for running HS4s on a 1500, you need a Euro spec intake and carbs, I don't have a line on this, check with the triumph guys like TS imports, ted may be able to find you one. I can build the carbs for you though, once you have the set up, I've got a HS4 carb cores, but you need the intake, linkages to make it all work.

09-08-2007, 04:05 PM
Lou, I ran a single HS4 on a Spit 1500 with no mods to either the ZS manifold or carb. You will have to get a bit creative with the throttle linkage, though.

09-08-2007, 07:06 PM
Yea Jeff you got what I meant. Just looking to run a single Carb on the original 1500 maifold. Nial runs one. But Emra only allows for a single carb on this engine.

09-08-2007, 09:09 PM
Lou, the SCCA allows just one HS4 on a 1500, too. That's the only reason I ran only one on the Spit. It was enough carb to support 138 HP.

09-09-2007, 05:23 AM
And SVRA and many of the other vintage have the same one-carb rule for 1500 Midgets.
Most of us just follow the SCCA GCR as regards rules. Keeps things easy.
EMRA will allow you to adapt any single carb however, as long as you use the original intake manifold. I'm using an S&S Super G (2-1/16 smoothbore with almost no venturi.....intended for racing Harleys). It's a honking carb for this application, but I'd run the SU at first, especially if you're planning on putting a1275 in at some point.
And if you don't put flares on that car (or just *tiny* ones), you can run vintage with it too. Radiused 1973-style rear fender (like mine) are fine for most vintage groups.

09-10-2007, 03:55 PM
Lou, I just remembered one mod I did to the HS4. I changed the float bowl rubber grommet to reorient the float bowl to the vertical. With the ZS manifold and an MGB HS4, the bowl is tilted.

09-10-2007, 07:26 PM
Thanks Jeff.

09-10-2007, 09:21 PM
Lou, here's a picture of the carb on the Spit. Note the position of the float bowl.

Hap Waldrop
09-10-2007, 10:49 PM
I've got a variety of the flaot bowl grommets with different positionings on them.

09-11-2007, 01:51 PM
Perfect Guys, There's nothing that cant be done here!