Trigo FIA on 427

[66gtk]

Will the Trigo FIA wheels (15" wheels reportedly have 3.5" BS on both front and rear) fit without modification/machining on the 427 ERA cars without issues? Will they clear the 12" brake option?

I understand that the stock Trigo 427 wheels require additional machining to work, so maybe FIA is an easier route? Besides, I rather like the look.

My car has under-car exhaust with 2.5" over the axle pipes so I need both inner and outer clearance considerations. Probably can't use a 295 tire in the back?

Thanks

[DanEC]

Troy - Lippy has FIA wheels on his ERA. I'm not sure if they are Trigo but you might PM him. I went with 255/60s on my car in the rear. Even they are pretty tight with 2-1/2 inch tailpipes - probably about 1/4 inch clearance after wrapping the upper section of pipe. I have plenty of room to the fender lip so a bit more positive offset would not hurt anything.

[1985 CCX]

If the backspace is the same on the wheels then they should.
My memory remembers ERA uses a special backspace that is not standard to all others.

If the car has Halibrand style then the brakes should work

[66gtk]

Originally Posted by 1985 CCX

If the backspace is the same on the wheels then they should.
My memory remembers ERA uses a special backspace that is not standard to all others.

If the car has Halibrand style then the brakes should work

Yes, the special backspace is true in regards to the 427 Halibrand style wheels. Both Trigo and Vintage stock wheels will not work without additional machining.

[66gtk]

Originally Posted by DanEC

Troy - Lippy has FIA wheels on his ERA. I'm not sure if they are Trigo but you might PM him. I went with 255/60s on my car in the rear. Even they are pretty tight with 2-1/2 inch tailpipes - probably about 1/4 inch clearance after wrapping the upper section of pipe. I have plenty of room to the fender lip so a bit more positive offset would not hurt anything.

Did you consider 275/60 for your rears? My SPF had those in the back.

[1985 CCX]

Bob at Vintage will usually make it happen wo cost.

[DanEC]

Originally Posted by 66gtk

Did you consider 275/60 for your rears? My SPF had those in the back.

It's stretching my memory a little but I believe 275/60 tires are around 28 inches tall and the max diameter ERA recommended was 27 inches. I was concerned about height but also width due to my tail pipes. That is for my #782 car. I'm not sure about tire size allowances on the earlier cars.

[66gtk]

Dan,

Did you order your Trigos from ERA or from Trigo directly? I ask as I am curious if the rear wheels were machined at all from stock. Do you know what your rear backspace is?

[DanEC]

Troy - mine are from Bob at Vintage and I ordered them directly from Vintage. Bob seems completely dialed in on the backspace and machining requirements for most of the popular replica manufacturers and he just takes care of it for you. Kind of a no-brainer on my part. I do believe they are specifically machined for ERA.

I don't remember Vintage having FIA wheels back when I ordered mine (I may be wrong) but he does carry them now.

[66gtk]

Thanks Dan. I find it interesting that the MTs you used are actually not recommended on 9.5" wheels per their website:
Mickey Thompson Performance Tires & Wheels

Do you have enough rim protection with your sidewalls? I wonder if it would make sense to use use 4 FRONT wheels all around? With the FIA design, they are marketdly different (front to back) unlike the Halibrand style, which simply has a deeper rim. May better achieve the bulgy muscle look in the back with the 7.5" wide rim?

[DanEC]

I think Mickey Thompson rated them up to a 9 inch wide wheel. The research I did seemed to indicate another 1/2 inch was not a deal breaker. BF Goodrich rated their TA radial in this size for up to a 10 inch wide wheel.. Also, Chev equipped the C3 Corvette with 225/70-15 tires on 8 inch wide rims for years and years - but that size tire is only rated up to a 7.5 inch rim. I had to pull my old notes out of my files to recall all of this.

My sidewalls are about 7/16 inch past the edge of the rim on my back tires. My front tires are rated for a max wheel width of 7 inches but I have them on 7-1/2 inch rims so they look pretty consistent with the rear.

When going with undercar exhaust and running them inside the wheel wells, you get into a lot of issues with tires and wheels - and the fact ERA has only allowed enough room for a 27 inch tall tire doesn't help. True to the manual, my 27 inch tires will lightly rub on the forward part of the wheel well housing on a good dip. I can lengthen the trailing arms a little to eliminate it but haven't gotten around to it yet.

I could have gone with 7-1/2 inch rims on the back and ERA even had an option to build a wider track rear assembly to move the wheels out to the fenders. I thought it would look a bit squirrely with a wider track and a narrower tire. The other option was to just mount a standard 7-1/2 inch wide rim on the rear with a 70 series tire and end up with the wide hip, street roadster look where the rear tires and wheels appear lost inside huge wheel wells.

In the end I went for the "Day 2" look of a wide hip street roadster that someone mounted SC wheels and 60 era tires on.

Compromises, compromises.

[66gtk]

Good discussion Dan. Thanks for weighing in. I'll keep you updated if I decide to make a move on wheels/tires. What I have now fits well, so I hate to deviate. Problem is I'd much rather be using a 15" wheel, despite the superiority of available 17" rubber. Compromises is right!

I think this is a good look below, that I would love to be able to achieve. Halibrand or FIA style - don't think it makes much difference. Going to be hard to achieve filling those rear wheel wells with what I have available today along with the large over the axle exhaust.



Presently, I can do this by simply painting my wheels black. Might be good enough? Here is what my car looks like right now. The stance is perfect and the wheel/tire/fender clearances are perfect to my eye. Just would rather have more sidewall than wheel.



a little photoshopping for a black paint job on the wheels...?

[DanEC]

Wow - that looks low. Have you measured your chassis height yet - just out of curiosity? Also it looks stunning. Nice find.

Knowing what I know now - I could probably have had Vintage reduce the backspace on my wheels by a 1/4 inch or so, to push the lesser-width tire closer to the fender edge and increase room for the pipes. However, mine seems to work fine and I haven't had any contact between the pipes and tires. I did wrap the pipes in the vicinity of the tire with header wrap as a precaution.

Going with oval tubing in the wheel well is also another possibility. And finally, I'm not sure 2-1/2 inch tailpipes are absolutely necessary. The exhaust temps past the muffler should be cooling down slightly which would allow the gases to shrink in volume some, allowing a smaller tail pipe. But the 2-1/2 inch pipes do look and sound mean.

Original SC cars apparently ran 9.00-15 tires on the rear but I haven't been able to find actual dimensions for them. Some cross-reference tables suggested a 265/60-15 or 255/70-15 would approximate them - but I'm suspicious of the accuracy of some of these cross-reference tables. Either of those would be a fairly tall tire - probably around 28 inches - and I don't think that will fit unless the earlier generation ERAs had a little more wheel well room. The tight point on my car is the forward wheel well panel just behind the seat.