Lead Substitute

[hemirr]

Anyone have any experience in using lead substitute?  I am having allot of trouble with knocking and preignition when motor is warm (live in South Florida so always hot).  I have backed off the timing back and it helped but not completely.  I have been using an octane booster with 93 gas but not enough.  I have access to 106 low lead and 110 gas with lead (over $6.00 gal) but trying to come up with a little cheaper option.

[Ghoste]

Have you tried just running a little bit of the high octane stuff mixed in?  6.00 a gallon hurts but maybe just mixing a gallon or so in would be enough to put it where you need?

[hemirr]

that is going to be my next choice.  But the problem is they wont pump it in your car,  its for "off road use only."  So its a real pain in the ass to haul gas cans across town to go get gas.  It the lead additive works it would be way easier.

[histoy]

I've used "CD2" lead substitute for off road vehicles.  It works well, is inexpensive, and can be purchased at Farm & Fleet stores.

[mikepmcs]

1 gallon toluene, hardware store. 114 octane. $18(price is going up cause they are on to us)

[hemirr]

toluene? 114 octane ?  Are you saying one gallon added to a tank (18-20 gallons) of 93 octans gas and it makes 114 octane ? Will just the octane boost eliminate the knocking?

[mikepmcs]

I gallon mixed will not make the gas all 114 octane.  One gallon of 114 octane toluene will raise your octane level way more than one of those off the shelf boosters in the store will.

check this article out and it has the formula in there as well so you can get an idea of what it will do.

http://www.elektro.com/~audi/audi/toluene.html

your scenario would go something like this.  based on 20 gallons capacity and 19 gallons put in + 1 gallon toluene.

(19x93)+(1x114)/20=94.05

[hemirr]

Do you recommend to runing a lead additive such as Octane Suppream 130 for added protection along with the toluene?

[mikepmcs]

Hemi, i'm out on that question.  I'm not that smart, sorry.  

It doesn't look all that bad though.  I wouldn't put too much faith in the raising the octane point system they are touting though. I'd be interested to see what all the ingredients are in the 130 stuff compared to other octane boosters on the shelf.  Looks like I'll be stopping at the auto store tomorrow to do a little consumer report action.

http://www.batterystuff.com/fuel-treatments/OS2q.html

[hemirr]

The Octans 130 is actually a full lead additive.  Been reading allot on it and it is design for engine that need the lead.  It isn't a substitute but the real stuff.  I have been thinking about giving it a try.  Anyway I WILL be giving the toluene a try.  Read allot tonight after your advise and everything I read says it works great.  I think the two together would be a great combo.

[c00nhunterjoe]

i think we may all be jumping the gun on this concern, first off what all is done to your engine ie- compression ratio, heads, cam etc etc etc. next how much timing are you currently running that you are getting detonation with 93 and octane booster?  i run an 11:1 motor on 93 with no additive and i can get away with a good bit of timing and no detonation.

[hemirr]

440 block zero decked with stock HP pistons not sure of final compression ratio. little hotter cam than stock HP cam.  906 heads with mild port job. Holley 4160 carb 750 CFM.  Anywhere from 5 to 10 degrees BTC on base timing ( been changing it allot) with about 34 total.  Here in South FLorida it has been real hot this summer  and the engine does run a little hotter than normal, but when running on highway temps are fine 180-185.  Still changing timing helps but not fully.  Ran a bottle of Lucas octane bost to a total of 10 gallons of gas tonight for local crusie in and seemed to run good  but engine was running cool, so.....?

[green69rt]

This engine probably should not knock and certainly not detonate so...a couple of questions and a couple of suggestions. 

This sounds like a very mild build but a couple of things come to mind from your description.  First you decked the heads but don't know the compression...find out!  Second the cam has been changed, was it degreed in or just put in and run.  I know this sounds like basic stuff but sometimes you just need to go back to the beginning.

[hemirr]

block was decked not heads.  Block was newer (74) and decked to match stock 68 HP pistons. Cam was degreed.  Stock 68 pistons, crank, intake.  This motor is not coming out or coming apart so how can I check compression now?

The thing runs like a scalded cat when it is cooler, just knocks when it gets hot which is not hard to do when its 96-98 degrees outside

[Sublime69]

Lead isn't going to solve your detonation, it's basically an upper cylinder lubricant. If you've installed hardened seats and valve guides you really don't need it and you can just throw in some Marvel Mystery oil to give your motor a little more protection.

I lived in S FL too (WPB area) before I moved here. There used to be a Sunoco off Okeechobee blvd that sold 110 for $3 a gallan back in the earlier 90's. I remember me dad having to get gas for his car there.

My Charger has the same problem now, I backed the timing off just a tad, and I mix 2-2.5 gallons of 110 Sunoco, 4 oz of Marvel Mystery oil MIXED with Lucas fuel stabalizer and fill up with Sunoco 93. It's not as bad as it sounds to do all that. I keep a little bottle that I have my mixed stuff in and throw in the 110 before I head to the Sunoco about 10 miles up the road. You just bring a 5 gallon can with you and fill it up, or bring a couple, or just pull your car out of site and dump it in there, just carry a funnel with you.   

[Ghoste]

I thought tetraethyl lead was added to raise fuel octane and the "lubricating" qualities were something they discovered by chance after the fact?

[b5blue]

I read somewhere that Oct. boost goes in reg. fuel only....as in lowers Oct. of super! Try adding it to reg. fuel.

[hemirr]

no mention on their web site but I will check.  Thanks

[green69rt]

block was decked not heads.  Block was newer (74) and decked to match stock 68 HP pistons. Cam was degreed.  Stock 68 pistons, crank, intake.  This motor is not coming out or coming apart so how can I check compression now?

The thing runs like a scalded cat when it is cooler, just knocks when it gets hot which is not hard to do when its 96-98 degrees outside

Yeah, sorry, I meant block was decked.

Sounds like it should work, can you rig a cold air feed to the carb so you don't run underhood air to it.  Also think about insulating the gas line inside the engine compartment.  I saw another thread about a similiar hot running engine knock.  May want to search it and see what they have to offer.

[hemirr]

Sublime - I live in the acerage and I am aware of the place off Skee's road.  SUNOCO 110 Leaded is now $8.09 /gallon and 100 unleaded is $10.00/gal, went there today.  I plan on running 2-3 gallons of 110 mixed with 93 and give that a try.  Hopefully timing plus new gas mix will calm it down.

[hemirr]

Ghoste - You are correct  Lead was added as an "antiknock agent" by increasing octane.  The lube qualities are small but important for order engines.  I had harden seats put in so not so important but the lead will help.

Check out this link - www.batterystuff.com/fuel-treatments/OS6q.html

[resq302]

Holy crap!  $60 for 6 qts?!?!?!

[Ghoste]

Yeah, but if I'm reading it right wouldn't that be enough to treat 10 to 15 tankfuls depending on how high you were raising your octane?

[hemirr]

Thats correct- it dosent take much.  I think the ticket would be toluene with a little of this would be real good.

[Ghoste]

If I could get it here I don't think I'd even bother with the tolulene personally but that's just my opinion, no science.