cosmicvette

Has anyone fitted these rims to a C3?




Seriously though, I am about to buy a set, and due to a little thing called the pacific ocean

, returning the wrong size rims is made a little more difficult/expensive. So I have spent the last 3 hours or so going over all the previous threads regarding them, there is plenty of info and pics but the problem is you get a little info here and a little info there and I can see why people ask about them again and again, because it can get confusing trying to compile all the info from the various threads.

I know you have probably done it several times before but it would be really good if anyone with TTII's could post a pic and list their rim dimensions, tire sizes and if they have relocated the e-brake, fitted offset trailing arms or a shortened rear spring.

I agree that TTII's have been put on so many C3's and I was looking at other wheels, but they just look so good and seem to match the cars look well, and also at the end of the day even if heaps of us fit them how many C3's do you see on the road anyway (especially here in Australia).

So here is my rough and 'concise' version of most the things that have been said:

First off here is a link to the good 'ole miata tire size calculator that is invaluable when deceiding on tires:
http://www.miata.net/garage/tirecalc.html

Remember when making plans on tire size to check TireRack or similar and make sure the tire sizes you want actually exist, as some don't.

American Racing makes the wheels and this is their website: http://americanracing.com/

They're really called Torq-Thrust II , but also referred to as Torque Thrust II,2 and TTII, TT2. You can get them either polished aluminium, painted centres (although some people think they are powder coated) and chromed. Most people seem to go for the polished aluminium, which I will be getting too, since they can be polished back up nicely and there is no coating that may peel off like chrome or paint can.

Also it seems that tire fitment can be dependant on individual cars since there will be difference in springs as they sag depending on age, also engine SB or BB and for other reasons etc etc, so when fitting tires at the upper limit you may run into clearance problems when other people don't.

Front Wheels/Tyres:
15x8, 16x8 or 17x8 fronts with a 4" backspacing seem to be the 'norm', 255/50R17 tyres seem to be the upper limit of fitment, and on early cars (68 up to 73-74?) you will most likely have to trim the inner fender lip for that size (as they did it from the factory on later cars), you may also get some rubbing on the frame at full lock on the inside of the tires.

Rear Wheels/Tyres:
Again 15x8, 16x8 and 17x8 with 4" backspacing all seem to fit and 255/50R17 tires seem to be the upper limit of fitment with no modifications.

On the rear the main problems you will run into, tyre and rim width wise are:

- handbrake/emergency brake cable and brackets
- trailing arms
- transverse leaf spring

It seems the e-brake cable and bracket are the first thing to cause troubles (for 255-275 approx.), then the trailing arms and transverse leaf start causing problems at around the same tyre size (around 275 and up). The e-brake brackets are fairly easy to relocate which gets that problem out of the way. The trailing arms can be replaced with offset trailing arms and a narrower transverse leaf (either original multi leaf metal, or monoleaf glass springs are available in short versions) also with shorter bolts will remedy this problem.

So when people are fitting rims bigger than 17x8 or tyres much larger than 255, it seems they usually do all three of the above mentioned things to get enough clearance.

If a wider rim (often an 18x10) is used, recommended backspacing goes from 4" to 5.5", obviously you can put much wider rims on and have them stick out of the guards but this causes all sorts of other issues to take into consideration (flaring guards so you don't have to fit really low profile tires, extra stress/load on rear wheel bearings etc).

The biggest problem from an aesthetic viewpoint seems to be choosing tyres that will fill the guards properly, as it is easy to get caught up in putting lower profile tires on and being left with a massive gap between the tire and the guard, use the miata tire size calculator and keep overall diameter in mind when making a final selection (standard diameter is 27.0" using this as a guide seems to be the go).

Staggering the rims front to rear (ie having a larger diameter rim on the rear) has also been done and looks quite nice, usually a 17x8 and 18x10 combo is used (if you have any other combo please post pics, especially a 16x8 front and 17x8 rear combo as I am curious what that combo would look like).

Well that is about it, I would really appreciate anyone making amendmants to this info and as I already mentioned anyones pics of their TTII's would be nice too.

As for what I will get it is most likely going to be 17x8's all round with 235/50R17's up front and 255/50R17's on the rear, but I am in the final stages of deceiding.

Cheers ,
cosmicvette

Vesa

17x8 with 245/45/17 now and soon 255/45/17

jotto

Have a look here and have a look at Mike William's Vette. She is a stunner ( I have seen and been for a ride in her )

I will try and get mike to post a reply here for you.

Jughead

Good info Cosmic. 16x8, 4" BS, 255-50-16 Goodyear Eagles. Had a little front frame rubbing when new on very tight turns but didn't last long. Thinking of moving the parking brake bracket because after 4 years now, I'm getting the tire rubbing A LITTLE on the cable. We'll see, I may be able to move the cable a little.

No T-tops, no rear window, no PS, AC, windows, brakes or door locks. I liked the 16's because they still show a little more tire than the 17 & 18's. Plus I couldn't afford the 17's at the time. they were over $330 at the time I bought my 16's.

danthony

I actually like the look of a thicker side wall on these cars, especially the chrome bumpers. It's just in keeping with the classic look.

16 x 8 is where I am headed as well!

gator79

that what I ordered I want my wheel well to be full. I don't like a gap above the tire. post pics when you do it cause my body wont be back on for a while yet

nutseynut7

[IMG][/IMG] [IMG][/IMG]
I am running 15 by 6 on front 15 by 8s on rear w 60 series tires

rastadr

550 front spring lowered car 1/2 to 1". offset trailing arms and a dual mount spring shortened 1/2" on each end to be sure, both from van steel. TT11's CL205's painted spokes. i wanted at least a 285 on rear which makes selection very limited. stock diameter was 27 and that doesnt exist with 285's in 17 which i wanted. decided on 26" and 255 45 i front and 285 40 on rear, both 26" wheles came from fastlane speed and rod shop in mission kansas 816-545 4747 considerably less expensive that the 20 or so places i checked. tire decision can drive you nuts. even multiple posts on this forum looking for the holy grail of rubber was fruitless except one member who helped put it in prespective by saying that your probably not going to push the tires to their limits very often in a street car so it doesnt make that much of a difference. like you i went to the tirerack tire survey for ultra high performance summer tires and in my chosen size the bfgoodrich g-force t/a dkw sounded good and ive ordered them. my personal favorite other than my choice is red73's bad *** decision which are 18's in back and 17's up front. beautiful way to go. keeping all four the same size is probably the smartest way to go id you use the car alot. you can rotate for longer life and even keep a spare. good luck and post pics when your done my digital camera should arrive this week and i will post as well

stingry

Cosmic,

My Vette gets here next week (Canberra). I have 17x8 TTIIs with 4" backspace. No rubbing or mods to car. I have 245/45/17s. Profile is low so I lowered rear a little. I will put on the 255s on the back when I am due for new tyres as it will look better for sure.

Pics below.

cosmicvette

Thanks for the replies, pics, and the details re suspension and car setup that really helps when deciding what sizes to go for. Plus I just can't get enough of looking at C3's with TTII's.

I totally agree with the need to fill out the guards, my car currently has 225/70R15's all round so they are even bigger than standard (27.4" compared to 27.0") and I like the way they fill them.

Stingry, glad to hear your car is almost here, it certainly looks very nice, I would love to catch up sometime. I am actually about to head off to the 'All American Car Day' at Castle Hill here in Sydney today, there should be a nice turn out of cars (hopefully including a few vettes)

Jughead, thanks for the details, I love your car, I have flicked through your photo gallery countless times...

Cheers,
cosmic

Jason Staley

Not really on the TT2 topic, but if you want to keep with 15 inch rims (instead up going to 17+ sizes) and need a good tire, Nitto just came out with some new sizes in its 555R performance tire: 325/50R15 and 275/60R15.

Thats the first true high performance tire I've seen for 15" rims in years. I think you could make the 275/60R15's work pretty easy on our cars.

71coupe

One thing to keep in mind if install a 15" model - the brake calipers are super close to the wheel, at least they are on the new Torq-Thrust D models. The older D models from the late 60's-70's had more clearance.

Back in the early 60's the America Racing "Torq Thrust" wheel was the choice for early mid years. When the '65 model came out with disc brakes, the original Torq Thrust no longer fit, so they came out with the "D" model specificly for Vettes. The back & front side were curved for clearance.

IMO they look great on midyears & early C-3's

Jughead

You can now get grey powder coated center TTII's....Zwede is running them. I think they're available in 16's & 17's.

Cosmicvette....don't forget about the ton's of pictures at my site too. http://www.corvetteforum.net/c3/themoneypit/

stingry

Cosmic,

Will send you an IM once we get the car rego'd. May go for a cruise to Sydney. My Brother and Sister both live in Sydney. Don't know how I will like keeping it LHD. May have to convert to RHD in a few years.

Cheers,

Pete

72on18s

Yes, I have 18" x 8" TTII's on my '72. I like the low profile tyre/big wheel look. I have seen a C3 with 20" TTII's on it , but even I thought that looked a bit much.
Anyway, I have 255/45 ZR18 Avon ZZ1 tyres and it's almost exactly the right diameter compared to 255/60 R15 (Although 45's don't crush down as much as 60's, so it would actually be very slightly taller in practice). I have confirmed with GPS that my speedometer is extremely accurate.To calculate diameter easily, try this link : Tyre/Wheel diameter
I do get a slight amount of rubbing against the chassis on full steering lock but it's no problem - just go to full lock then back off slightly - easy . I bought my wheels from another UK Corvette Club member who obviously had done all the measurments, but 4" backspacing looks about right. Absolutely no problems at all with handbrake etc., and the brackets have not been moved. They also clear the calipers fine. I just need to lower the back slightly, which I plan to sort this year.
A few pictures of my car are here if you are interested : Mike's '72 Corvette on TTII's

cosmicvette

Cool 18x8's all round haven't seen that before!

Does anyone have pics of 255/45's on 17x8's all round?

Also, does anyone with TTII's have VB&P's "Street & Slalom System" installed (550 front springs and 360 lb/in monospring rear click here to see the kit I mean ) as I will probably be installing that kit at the same time I put the wheels and it will probably alter my ride height considerably.

Cheers,
cosmic

Gordonm

I currently have 255 45 17s all around but am going to 275 40 18s in the rear on 18X10 rims.
Here is a picture of the 255 45 17s

gator79

is your suspension lowered any?

Gordonm

Yes the front coils are 550s and the rear has 8 inch bolts at the lowest they can go.

Grinchia

I followed Jughead's lead and went with the 16"x8" for my '68, with Kumho tires (I wanted to get tire height as close as possible to stock to avoid undue inaccuracies with my speedometer, and Kumho and Pirelli were the only two options for this rim size...17" rims have many more tire options available). I initially had a little rubbing on my (poorly fitting) Kustom headers up front, but that disappeared with the Jet-Hot coated hookers I bought last year. I didn't have to move my E-brake and have no rubbing there. My fiberglass rear spring comes close enough to the rear tires to make me a little nervous, but I haven't taken the plunge and shortened it (yet...). They look great! I like having a little more tire showing, the modern "big rim skinny tire" look is out of place on a C3 IMHO. I can guarentee you won't be disappointed in the look once you remove the factory rallys and pop on these rims