It is a good question. 17's are made for older cars, so it's likely they would drop out of production first. Using Tirerack's listings as a guide to availability, there are 36 speed rated 235/55-17s (1% too small in diameter) and 30 235/55-18s (3% too large in diameter). Or, you could really go crazy and get some Porsche-sized 265/45-18s. They're almost exactly the right diameter and would just fit on a 9" wheel in the QP3 wheelwell, maybe the Bora rear one, too. Not cheap, except in comparison with the XWX, and there are only four types listed. The problem for me is that 18" wheels on either the QP3 or the Bora are obviously more modern than the car. In fact, I wonder if you could even do an 18" wheel that really looked like the original. If not, you might as well admit it and just find some nice looking modern wheels. I think 17s leave just enough sidewall to look "old", especially to eyes used to 20" wheels with rim protectors. I bought some 17x9 wheels from Ebay, right bolt pattern, wrong offset, in the hope that I could squeeze them in to see how the tire would look. Unfortunately the 16mm difference in offset is too much. There's no point in mounting a tire - I can see from just the bare rim that it would hit the lip in the rear. I think 9s will fit and they are just a little over the recommended width range for the 235, but they'd have to have the correct 40mm offset or near it. I've also looked at 5 x 115 and 5 x 112 OEM wheels. Apparently with centering rings and wobble nuts they'd work. I'll have to scrounge one and see. There are some Mercedes AMG staggered sets, 18x8 and 18x9 with nearly correct offsets that look right on big, imposing cars. The Bora is much tougher to play with. Maybe 4 x 130 was common as mud when they chose it, but other than certain VWs and the 914, I can't find any other users today.
Size Diameter Width Tread Depth Tread Width Rim Range Load Range Max Load Max psi Weight Revs Mile 205/50ZR17 25.1" 8.4" 10/32" 8.7" 5.5-7.5" XL 1433 lbs 50 psi 22 lbs 832 215/50ZR17 25.5" 8.9" 10/32" 7.5" 6-7.5" SL 1356 lbs 51 psi 23 lbs 819 225/45ZR17 25" 8.9" 10/32" 7.5" 7-8.5" SL 1356 lbs 51 psi 23 lbs 837 225/50ZR17 25.9" 9.2" 10/32" 7.5" 6-8" XL 1653 lbs 50 psi 25 lbs 807 225/55ZR17 26.8" 9.2" 10/32" 7.5" 6-8" XL 1819 lbs 50 psi 26 lbs 781 235/45ZR17 25.4" 9.3" 10/32" 7.7" 7.5-9" SL 1477 lbs 51 psi 24 lbs 824 235/55ZR17 27.2" 9.7" 10/32" 8.1" 6.5-8.5" SL 1709 lbs 51 psi 24 lbs 769 245/40ZR17 24.7" 9.8" 10/32" 8.5" 8-9.5" SL 1356 lbs 51 psi 25 lbs 846 255/40ZR17 25" 10.2" 10/32" 9" 8.5-10" XL 1653 lbs 50 psi 25 lbs 835 What I am finding in most tires is that there is an offering in the right size but not with the larger rear. We would either have to go to 18" rear like the Pantera guys do or stick with narrower tires. You could go with the 235/45 front and 255/40 rear which are both 25" but this is quite a drop over the 696mm stock size.
Watch that load rating carefully too. It drops off quickly once you take the car up to the higher speeds so if you are going to drive it at 130+ mph which one is apt to do with all that extra power, say on the autobahn, you need to recalculate the load rating. Contact the tire manufacturer for their guidance on that for the specific tire in question. In any event a diameter of 25" versus the the originals is not a trivial change but you can deal with that except that it may look kind of small in the wheel opening.
265's won't fit the Bora and the 255's I had on were unique at that time in that they were actually narrower than most other 255's. There are vintage race tires in some of these sizes for the original rims.
Bob (or Art, or other)-- my Bora re-shod lately and I'd tried to go wide in the rear with some 255s (I think I recall) that were about 9" tread. As choices were limited then to interim mfr (being Radial T/As) I found they had a wide selection of the sizes that seemed relevant to my car. Had to send back the wider tires and limit myself to the 15" 225x70 -- owing to anything larger rubbing the INSIDE of the rear wheel well UNavoidably. Until learning more about spacing for use of the outside space, limited myself to your suggested quarter inch spacers to move everything outboard. OK so far. However, still interested in performance level tyres, but only after resolving 15" wheel issue and whether up +n or more is really advisable. BUT, this is a serious limitation. A VERY high performance wheelmaker I know closely said Backspace/offset is frequently overlooked in these plans. PS: I'll never allow welded anything on my wheels. Over, NE PS: on other fronts--looking to do the upgrade for best/easy modern Alternator. 90amp or more, likely. Can you recall the thread to follow for that, or otherwise direct my search??
245's with a .25" spacer work without issue. 255's I wouldn't try with the stock wheels. Besides, other than a few vintage race tires there is nothing in those sizes. 225's are too tall and the weak sidewalls will make the car handle poorly if it's just an inexpensive passenger car tire. XWX's are plenty stiff enough though. I just don't think much of them as a tire when compared to what we used to be able to get for thes cars. Someone should check these out CR6ZZ | Avon Motorsport they have a 245/60 but no 235 ... so 215/70 or 226/65 for the front. They're also at least $425 each.
Tomorrow I am going to get a first look at a 17" x 8" reproduction of the Bora wheel commissioned by my friend Bob. He decided he likes the hubcaps from the earlier wheels so new ones are going to be made. After I inspect a prototype, I'll see if I can figure out how to post a picture on Ferrarichat so everyone can look at it. Wish me luck on both the new wheel and trying to get a picture posted.
Hi I have been continuing my search for the right unit. I did see on the QPIII thread the 440 which fit in the engine bay but to me looked a little old and I am told it is a heavy unit. The QP III is 70s and 80s not 60s. So someone on the QP III thread mentioned the Kaase P38 unit and to my mind this really does look the business. It is reminiscent of the Maserati unit as it has the flat top and the trumpets. I do think this is the type of unit to build a car around. Does it have enough power (over 500bhp), sound right etc. It would be mated with a Tremec 6 speed. I will load up some pics. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Just for the record, these are all pensioners. The small block Ford hiding under the billet stuff came out in 1962 and the Chrysler RB in '59. The grandaddy is the Maserati V8. Depending on which iteration you choose as the start, it was designed in either 1954 or a few years later. These days you can build both the Ford and Chrysler engines (and old Chevies) using only aftermarket parts, including aluminum blocks, heads and accessories. I don't follow drag racing, but apparently Jon Kaase has a good reputation in that field. Those engines are optimized for wide open throttle runs, 1/4 mile at a time. They might be good for daily use, but I doubt it was a design priority. My son's business built a 510 cu in (8.4L) Ford with Kaase heads for a customer. It isn't very practical, but he uses it only to cruise Sonic and impress his friends. It seems the more modern an engine is, the less interesting it looks. Part of that is due to the mass of wiring and sensors required, but I think a part is that it's easier to slap on some molded plastic than to style the engine parts themselves. I don't know why they bother - those of us who understand and like the mechanical bits will be turned off and those who don't will never look under the hood!
Hi Good point on the motors. The thing is that the Kaase looks like a work of art and has styling details similar. Flat top and trumpets. The fiddly plastic top on some of the modern motors is boring and does not really "fit". They say they have a street version as well so we will see what they say. I am not settled yet of course the LSA is a good bet. Edelbrock has a version also. Anyway, I thought I would post this early picture. I think this is a different wheel from the production versions and more similar to the schematic picture I posted earlier. PS It looks a bit like the E Type wheel with 10 holes. I think the production version has 12 holes. See pic Image Unavailable, Please Login Image Unavailable, Please Login
I think those are DeTomaso Deauville wheels. The suspension and possibly some of the body structure of the QP3 came from that car. I like those early simple alloys, too. They mimic the steel wheels that came before. Ferrari 300 GTCs and 275GTBs sometimes used a style like that. Are those from Realm Engineering?
I think you are right. Keen eye. The early QP III rode on the DeTomaso Deauville wheels. Image Unavailable, Please Login
Here is the picture of the QP IV Evolutzione wheels. PS I prefer the style with the holes around the rim. Image Unavailable, Please Login
Gents Take a look at Bundas 18 X8 Lexus wheels. They seem to fit and look OK . What if we just got replicated originals in 18". This would give us the originals for show and a modern full range of tires
I don't know if this has already been mentioned so sorry if this is a repeat question. You guys are focused on the QPIII even though this is a thread about a restomod Ghibli correct? As a Bora owner I'm somewhat interested in what you're doing as I think a custom cast wheel like the original can be done so that both the 4 bolt and 5 bolt configuration can be accommodated. What's not so clear once you get into a much lower profile tire as would be necessary for an 18 rim is the idea that rim width would now HAVE to be different for front vs rear because if you're going to have wider tires on the rear these are no longer 70, 65 or 60 series tires which can be fit to a variety of rim widths but the 35->45 series tires cannot. Or are you thinking one size on all four corners? Then there's the backspace issue if you're running much wider tires all around. If you could come up with a set of front & rear rims that would accommodate all of this and only the centers would be machined differently that would be terrific! Three piece wheels are a popular solution for these exact reasons but I haven't seen a mockup of a three piece design that looks like the original, seems impossible?
I had a long boring post ready and lost it, so here's the short version: an appropriate 18x8.5 wheel for, and from, a Maserati. The rears are 10.5" and probably won't fit, but use four fronts. William might have mentioned this before - sorry if it's a duplicate. Image Unavailable, Please Login
Hi Looks nice. What is the source and costs. Do you know the dimensions? Is this a road set up or racing?
Hi Not sure if I posted this but I did have an earlier posts. He was right in that Ghibli resto mod has become just resto mod. Do you have a source for these or just ebay of wrecked cars? Best
Just Ebay. The bolt pattern is right. The offset is 50.5 instead of 40, but that can be corrected with spacers if need be (3,2,1... George?). I don't know about the center bore, but that can be fixed too, either direction. There are a lot of V and above 245/50-18 tires available and that would provide a diameter almost exactly correct (about 27.6 vs 27.44). There are even more 255/45-18s. They're slightly shorter at 27", but also slightly wider. That must be a more common size because the prices are lower also. As for the Ghibli restomod, I think post #27 pretty definitively answered that one! That leaves the tough nut to crack, the Bora, but in my case it isn't urgent. That car has fairly new Pirelli 235/60 tires. The QP3, on the other hand, has ancient Michelins; the spare is the original XWX. I need to do something just to drive it in the neighborhood.