I have a '77 Triumph Spitfire on which I put some mag rims so I could put wider tires on it. I have a problem with the studs breaking–the last time I had one stud left before I got it stoped. I have been told that vintage racers have an stud from an American car that has harder metal that they use to prevent this problem. Does anybody know what kind of car/stud they were talking about–or other suggestions?
Arelated question is when I rebuilt the engine the timing sprocket had 3 punch marks on it. I picked the wrong one. Can anybody tell me how to pick the right one?
Thanks for all help.
Didn’t you have a manual when you rebuilt the engine? I would think that the timing would be covered in the manual. Rocketman
Steel products from CHINA are sub-standard strength, and hardness. Those may be what was put on your car. Dorman brand is a reputable source of wheel studs. Get them from NON-CHAIN store auto parts stores.
Your extra-wide rims may have the wrong ‘offset’, putting extra stress on the studs. Do you know if they have the correct offset?
The wheel bearings will be the next thing to go. The wheels must not be a correct fit. The studs aren’t supposed to support the weight of the car. The wheels aren’t fitting correctly on the hubs.
This sounds extremely hazardous to me.
I hadn’t thought of that - sounds like these rims don’t fit correctly to the brake drum/hub, too. Not good.
The only bonafide wheels I know of that fit the Spit correctly are Wolfrace, Minilites or the correct pattern spoke wheels. Wolfrace & Minilite were the campaign weapon of choice due to inherent weaknesses in spoked wheels at the time.
Large wheel offsets won’t work on a spit unless you drastically re-engineer the rear end. I’d advise talking to a Spit specialist or one of the clubs, you can’t just stick any old wheel on the car and expect it to stay on during dramatic moments.
As far as the timing marks are concerned, you don’t say which engine but for a 1300 - Set the #1 cylinder at TDC and with .050 clearance on both intake and exhaust valves of #4 cylinder, with your engine’s 1,3,4,2 firing order the intake should just be starting to open at the correct timing. The .050" clearance is just starting to close that gap.
You should be able to determine the correct timing mark when the engine is set up thus - a blob of paint should prevent future confusion.
yes, I used the manual. It said “line up “THE” puch mark.” My problem was that there were 3 punch marks by the time it got to me.
My ignorance. I not only don’t know if they have the correct “offset” I don’t even know what an offset is.
Google ‘wheel offset’, it’ll tell you it’s the distance from the center of the rim’s width to the mating surface between the wheel and hub, I believe.
http://www.tirerack.com/images/wheels/tech/offset.gif
thanks to all for help/advise
The engine started as a 1500. It was ported, honed, balanced etc. and then the shop where I was having the work done went belly up and I had a large basket of parts to put back together. A steep learning curve for me. Will this same thing work on the 1500?
Yes, the same. The gap measurement itself isn’t critical when re-assembling an engine, it’s more important to ensure the gaps for both valves are the same.
- Referring to your original post regarding wheels, if you are planning on campaigning this car I’d suggest replacing the timing gears and chain with the GT6 duplex unit. It’s a direct replacement and is a much sturdier option for race work.
Many performance aftermarket timing sets have a sprocket gear with 3 notches for setting the valve timing depending on desired performance. The timing chain and sprocket set should have come with instructions to set the proper timing to the desired performance. Each keyway should have a different mark to line up the timing to distinguish between neutral setting, advanced, or retard. Here’s a typical installation sheet from Edelbrock, the manufacturer of your timing set should have something similar: http://www.edelbrock.com/automotive_new/misc/tech_center/install/7000/7800.pdf