1958 MGA, unleaded?: Classic Cars forum: Classic Motorsports

Forums » Classic Cars » 1958 MGA, unleaded?

Dec. 3, 2009 4:12 p.m. mr2peak New Reader

My dad just bought a '58 MGA, getting here tomorrow from Hawaii. Beautiful car...

Does an all-original '58 MGA need leaded fuel? The head has never been replaced/rebuilt.

Thanks James
Dec. 3, 2009 5:36 p.m. Karl La Follette HalfDork

http://www.mgexperience.net/ great for mg advice
Dec. 3, 2009 6:06 p.m. DeadSkunk New Reader

You'll get some valve seat recession over time, but you can simply put in hardened valve seats, when the time comes to rebuild the head. You'll be OK for a while.
Dec. 4, 2009 4:16 a.m. aeronca65t HalfDork

Yeah, over time you might see some valve seat wear, but only if you drive that car real hard and run up lots of miles.

Assuming it's more of a street toy than a high-mileage daily driver, my guess is that you'll run for many, many years before even seeing a little recession.

My '69 MGB has run for years on unleaded with no measurable seat wear. I'm also racing a vintage Sprite on mostly Sunoco GT unleaded (100 octane). With over 50 weekends of racing, the valve seats show no excess wear.
Dec. 4, 2009 12:29 p.m. Leo Basile Reader

Yeah, what he said!
Dec. 4, 2009 3:49 p.m. mr2peak New Reader

Cool guys, thanks, just got it home to my dad's.

We had the car running with my dad in the front seat, I told my mom to come up to the road. She took it pretty well... Think she's getting a vacation soon. I'll post pics when I have them.
Dec. 4, 2009 6:34 p.m. kreb Dork

Love the looks of MGA's. Been afraid to drive one, because I've been told that they're dynamically disappointing.

This one's been out there for months. There must be something terribly wrong for it not to sell at that price.

http://sfbay.craigslist.org/pen/cto/1491761206.html
Dec. 4, 2009 8:51 p.m. aeronca65t HalfDork

Gackk! That one is a terrible colour!

I race against them all the time. In terms of handling and speed, a race-prepped, stock-ish MGA is similar in performance to a similarly set-up 1275 Sprite. In other words, decent.

My first street car was an MGA. Not as comfy as my MGB, but nice to drive. Very "pure" and "direct", sort of like an old Lotus 7.
Dec. 6, 2009 6:11 p.m. ronbros Reader

i suppose they were good cars ,, but i had a new 1957 Fuellie corvette ,4spd. at that time!

never was much intimidated by many cars back then.

in 1958 added LSD and traction bars, that took care of most shortcomins.

like any old dude,(shoulda kept it)
Dec. 8, 2009 9:44 p.m. dougie Reader

Hey James - Maybe when your dad gets tried of the new/old MGA he'll let you take it to the track. We have some of the fastest MGA's in the country here on the West Coast. I always enjoy running with them, when prepared right they can run away from a lot of higher HPer cars. http://www.youtube.com/watch?v=4zVTq-9VMws

Dougie
Dec. 13, 2009 12:18 p.m. wspohn New Reader

If you use the car for highway use - long periods at high speed, you'll need to redo the head much sooner than you will if you just use it for driving around town once in awhile.

I have a couple of MGs (MGA, MGC) with original seats that are holding up well, and one V8 I use for highway work that isn't.
June 7, 2011 8:01 a.m. masterjohnson New Reader

what will happen to my car if use different fuel with high octane? what will be damage inside my engine?
June 8, 2011 8:49 p.m. wspohn Reader

masterjohnson wrote: what will happen to my car if use different fuel with high octane? what will be damage inside my engine?

You'll just waste a lot of money. There isn't a stock MGA built that won't run on 89 octane, and often 87, unless the head gets carbonned up in which case the solution isn't to switch to premium to temporarily cure the ping, it is to remove the head and decoke it.
June 8, 2011 8:51 p.m. wspohn Reader

ronbros wrote: i suppose they were good cars ,, but i had a new 1957 Fuellie corvette ,4spd. at that time! never was much intimidated by many cars back then.

One of my favourite opponents on the track was a 1957 injected Corvette.

I used to turn a half second a lap faster times than he could (I had handling and brakes, he had acceleration) but if he ever got out front, there was almost no way I could pass him (Corvettes can be very wide in the corners!)
June 9, 2011 11:30 p.m. speedygonzales

one the first place why would you force your car to run on high octane fuel. it is always written on the manual so just follow what is in your manual. it will not damage your auto parts that much but it will surely hurt your wallet because of bad mileage.
June 10, 2011 6:24 a.m. AndreGT6 Dork

High octane. My GT6 calls for 100 in the manual.

With reg she was just plan mad. So its Sunoco 94 when I can or Shell 91.

I do have a digital ignition setup which I can dual load timing maps. So right now my timing is optimized for high oct, but if for some reason I had to use reg 87 I can flick a switch and retard the timing.

Gotta love that.

A.
June 12, 2011 4:54 p.m. wspohn Reader

AndreGT6 wrote: High octane. My GT6 calls for 100 in the manual.

Indeed it does - but they mean 100 RON, not the North American system which rates R+M/2.

You've been wasting your money all these years due to a misunderstanding of a British manual. There is about a 5 point difference - all your engine needs is 93 to run without ping. The GT6 has 9.25-9.5 compression and will normally run just fine on 91. My MGC, for example, runs well on 87 or 89 without ping at stock timing.
June 15, 2011 3:40 p.m. Basil Exposition Reader

As others have said, it is not that big a deal unless you plan to put a lot of higher rpm miles on the car.

Although you can buy a lead additive substitute at most auto parts to help reduce any valve recession. It is what I do with my MGA.
June 15, 2011 5:25 p.m. willie

if you want,( go to wal-mart get a lead additive]........lead was used with all brit engines in the 50's......maybe it is the one elvis used......good luck james w shane
June 15, 2011 9:03 p.m. ronbros Reader

just run it , maybe in 5yrs you may do some valve seat work.

cant hurt much you will replace the valves and seats anyway.