Non hardened valve seats. Do I need a additive?

cdnpont · Canadian Poncho Superstar!

Non hardened valve seats. Do I need a additive?

87 player bird · Poncho Master!

I used to run S.T.P lead additive in my 69 GTO. If you don't, you run the risk of distorting the valve seats.

03cts sport · Uber Guru

is that common. Does anyone/everyone else us an additive in their pre-70's?

seventy2plus2 · Canadian Poncho Superstar!

There are various schools of thought re the use of unleaded fuel in our old engines. At one of the POCI shows John Sawruck indicated the use of lead substitute is like throwing money out the window. I bought a number of STP bottles on sale at Liquidation World a number of years ago, and used it in my hardtop. I still have quite a few bottles left. Basically, keep you money and don't waste it on lead substitute.

As for your choice of octane for your 10:1 motor, give mid-grade a try. If it pings move up to premium. My 10.25:1 motor needs premium.

87 player bird · Poncho Master!

Lead was a lubricant, so if it's not there without hardened valve seats.......

norontcan · Canadian Poncho Superstar!

I use a lead substitute. Whether its absolutely needed or not has always been a contentious point and the subject of many magazine articles and blogs.
If your running her hard then its probably a good idea.
The one I use is about $10US for a bottle which does up to 320US gallons. Pretty cheap insurance. Have a bottle in each car. Don't put a lot of miles on any of my cars so at less than $10US/yr total it gives piece of mind and if it doesn't help I'll be a long time finding out.

With modern gasolines you're probably best to experiment with mid grade and hi-test and see which performs best for your application. By that I mean if you're doing casual driving you may not need hi-test but if you're pounding it...well.

Canadian Poncho · A Poncho Legend!

What I've heard is lead substitute is only required if you drive the hell out of the car- high revs, run it hot etc. I've had old cars since forever and never ran an additive. For the amount you'll drive your car Mark I'd go with Sunoco Gold. Get a points card and at least over time you'll earn some free gas. That's what I run in the Park Ave since it requires premium. Even with Gold my knock gauge still shows some pinging on heavy acceleration..

Todd

2drpost · Uber Guru

same here, the limited amount you'll be using the car, you don't need an additive.

59poncho · Poncho Master!

i was thinking about this very question today, and what about on a 59 283? I just put regular unleaded and it seems to drive fine and i dont drive it hard, but i really dont want to hurt the engine. Should i just put a premium in and not worry about a lead supp.?

59poncho · Poncho Master!

should i look into diiferent heads with hardened valve seats?

Canadian Poncho · A Poncho Legend!

I'm not sure what compression ratio they ran in 59. Mid grade might be fine. Don't worry about an additive IMHO.

Todd

carnut70ls4 · Addicted!

Back in the early 1970s, I ran a 1968 Mercury Taxi, part time for extra money. It had a 302 V8, with about 300,000 miles. When we filled up each and everytime, we added a cup of transmission fluid, before we put the gas in. If my old memory serves me correctly, never had an ounce of problems with that old merc and I drove it hard. Have often thought of that mixture, did try it once or twice in an old big block 72 vette years ago, seemed okay, but my buddies thought I was crazy. Anyone heard of that??

Elroy · Poncho Master!

I definitely hear of many applications using tranny oil in the gas or diesel for that matter. Reason being, ATF has the most additive( detergents) of any oil because of its high tech nature. In that, you will clean your engine like a fuel cleaner, or oil additive as well to degum or clean the varnish out of an engine thats been sitting. Otherwise, i would not use it continually. THe Fuel Lead additives R&D tests that I have seen have all claimed that you are better off without it as many members are saying. The additive seems to deposit itself everywhere but on the valve seat causing way more issues down the road. Burnt valves or valve seats just don't seem to be a big common problem out there either ??? my 2bits...

Astro Jet · Poncho Master!

With respect to lead additive, it is only really needed if you are putting a heavy load on the engine, either through trailer towing or racing. I stocked up on real lead in gallon jugs several years ago. Bought it at a speed shop in Buffalo.

What everyone should really be worried about is the lack of zinc and phosphorus in all current regular motor oils you can buy. If you run off the shelf stuff from Crappy Tire or Wally-Mart, you are guaranteed to ruin any pre-1990s engine with flat tappet lifters. You need to use either something like Brad Penn motor oil or an additive like ZDDPlus or Cam-Shield.

-- Edited by Astro Jet on Tuesday 22nd of September 2009 12:14:24 PM

Canadian Poncho · A Poncho Legend!

Someone was telling me motor oil for diesel engines was best for our cars. Anyone else hear this?

Astro Jet · Poncho Master!

Up until recently Shell Rotella diesel oil had a relatively high zinc content, but not any more. If you want to educate yourself on this subject, just go this site:
Bob is the oil guy, yes, a site completely dedicated to motor oils!

There have also been articles on this subject in magazines like High Performance Pontiac and Muscle Car Review, maybe others, in the last year or so.

http://www.highperformancepontiac.com/tech/hppp_0606_understanding_motor_oil/index.html

http://www.highperformancepontiac.com/tech/hppp_0802_pontiac_performance_engine_oil/index.html

dualquadpete · Canadian Poncho Superstar!

I was running Shell Rottella 15/40 up till now, yes, they took the zinc additive out, will have to use the aftermarket stuff now. I also put lead additive in every 3rd. tank. On long hauls at highway speeds, the "hammering" of the valves against the seats, can make the seats recede into head. This doesn't show up right away, but over time it will, I put between 4000 to 6000 on the Catalina per summer, have to use Sunoco "94" as comp. ratio is somewhere around 10:50 to 10:75 it will run on mid grade if I "dump" in some booster!!!! Pete

SGS Welding · Guru

I realize this thread is 7 years old But could a fella not go to your local airport and purchase some avgas And mix a little in the tank with every fillip? Gets you a little lead and some higher octane Have heard this is helpful

427carl · A Poncho Legend!

SGS Welding wrote:
I realize this thread is 7 years old But could a fella not go to your local airport and purchase some avgas And mix a little in the tank with every fillip? Gets you a little lead and some higher octane Have heard this is helpful

you soon get tired of running to Goderich for Av gas... just add some additive once in a while

cdnpont · Canadian Poncho Superstar!

cdnpont wrote:
Just wondering,

With the 327 in my GP being a leaded fuel engine, will I need any kind of fuel additive to compensate?

Also, it's a 10:1 engine. Will mid grade fuel suffice?

Mark.

Moderator, please delete the above thread.

long stroke · Canadian Poncho Superstar!

Astro Jet wrote:
With respect to lead additive, it is only really needed if you are putting a heavy load on the engine, either through trailer towing or racing. I stocked up on real lead in gallon jugs several years ago. Bought it at a speed shop in Buffalo.

What everyone should really be worried about is the lack of zinc and phosphorus in all current regular motor oils you can buy. If you run off the shelf stuff from Crappy Tire or Wally-Mart, you are guaranteed to ruin any pre-1990s engine with flat tappet lifters. You need to use either something like Brad Penn motor oil or an additive like ZDDPlus or Cam-Shield.

-- Edited by Astro Jet on Tuesday 22nd of September 2009 12:14:24 PM

X 2 !!!!!! Right on the mark.

SGS Welding · Guru

Good point 427 In my situation my neighbor is a pilot and has a plane in Huron Park He brings avgas home whenever requested But your right may not be handy for everyone...

dcneric · Poncho Master!

I think I posted this in the past.

www.gnttype.org/techarea/misc/octanebooster.html

The author Richard Lassiter is the same fellow that took his 455 GS and whooped a hemi car reapeatidly in stock form back in the 80's that was documented in muscle car review. He went on to race GN turbo cars.

57 Pathfinder · Guru

Hot Rod article on the GS Stage 1 vs the GTX hemi with video...

www.hotrod.com/features/history/stories/1404-hemi-killer-buick-gs-vs-gtx/

An excerpt:

Neither man had any clue of the history they were making. Both of their cars were slightly modified with slicks, headers, and blueprinted street cams. Lasseters Buick also had an Edelbrock intake and Holley carb. Lasseter drove it 125 miles to the track and had a modicum of experience racing the automatic transmission car down the 1,320 (no NHRA stock class experience, as reported in the original article).

Badie trailered his car, was new to the dragstrip, and his 70 Plymouth GTX four-speed car was new to him. That and his arrogance (his words) were his downfall. The Buick creamed the Hemi in the quarter-mile: 12.30 to 13.03 seconds. The Mopar guys--and the world--were in shock.

The fallout was immediate. Accusations of Stage 2 parts or a full-honking Kenne-Bell-built motor in the Buick came from the Mopar camp. Other folks challenged Lasseter and his Buick to a race. He still owns the GS to this day. Meanwhile, Badie sold the GTX soon after.