Gasoline of choice
 

I have been seeing advertisements with valve from a car which had been using brand "x" gas, typically built up with gummy deposits, verses advertised gas w/ nitrogen additive (Shell) or Techron (Chevron and Texaco), which is deposit free.

For those who takes motor apart as a hobby or professionally, is it common to see so much gummy deposits in internal components? Does choice of gas (obviously staying away from non-major brand) make difference or are these ads just b.s. marketing?

My personal choice had been Amoco and Mobil. Of course, Mobil got absorbed by Exxon and Amoco, by BP. Recently I have been running Exxon but had been considering switching to Shell.

Re: Gasoline of choice
 

As long as your valve seals and rings are in good shape, it dont matter. Late model efi motors run lean and clean.

Re: Gasoline of choice
 

When I pulled my injector housings for porting, the secondary intake valve stem was totally crusted up. I doubt it had to do with gasoline choice so much as oil through the intake, leaky injectors, and a lack of using the secondary system often enough.

I think premium octane and frequent exercise is the best way to keep the engine running clean.

Re: Gasoline of choice
 

There was a thread a while back about this what's the best gasolines e.g. "top tier" gasolines. (C-link to Keith's post reference to Marc Hiabeck's info page).

http://www.zr1netregistry.com/forum/...ines#post53838

I recently pulled my plenum and injectors for porting and had a chance to look at the nozzles. They were spotless, as were the valves of the primary valves. The secondary valves had a thin layer of a tar-like (oil) goo on them.

NOT on the top tier list, but the fact that the injector nozzles were spotlessly clean was a :thumbsup: vote to the BP/Amoco. The fact that the primary valve was also spotless might suggest there was some good cleaning going on there. There is "some" oil that gets back into the plenum of the LT5s, and I figure the fact that the secondary throttle plates are open relatively rarely in normal driving/cruising was probably the reason the valve didn't get cleaned as well as the primary.

That has all changed now, now that I've opted to pull the secondaries and run on all 16. We'll see. Who knows...Mebby no throttle plates or even rods and a clean valve might be worth another 3-5 hp! Or, mebby not:rolleyes::mrgreen: But! It can't hoit!:thumbsup:

P.

FWIW,

P.

Re: Gasoline of choice
 

I generally get BP/Amoco as well, mainly because they are close, and they always print a receipt. The local Shell station is closer, but almost never has paper in the reciept printer, which pisses me off to no end.

FYI, but "Top Tier" is really more important when running regular or 87 octane. Most premium fuels have good additives, it's in the base stuff that some places cheap out. Top Tier is a rating of the whole fuel lineup, not just premium. BP/Amoco's premium would certainly meet the Top Tier criteria, presumably their base grade stuff does not, which is why they are not certified.

Re: Gasoline of choice
 

Makes sense. I guess this is why there are a lot of discussion over oil catch can. It is tough to dig into secondaries without drawing a lot of attention.

Thanks to all for your thoughts.:cheers:

Re: Gasoline of choice
 

Marc H had mentioned once to me that the threshold for de-activating the secondaries was pretty low, something like 4-5% throttle. So if you hammer it in say 4th gear to get them open, you can let off and cruise with the secondaries flowing to clean things out.

It's probably helpful to have a scan tool or something on the car to ensure they are still activated.

Re: Gasoline of choice
 

I only put name brand high octane premium into the ZR-1.

I have tried off name regular for other cars, and at times have gotten a check engine light pop on. When I go back to a name brand, the dummy light goes off.

I seek out Mobil/Exxon whenever possible.

:cheers:

Re: Gasoline of choice
 

Usunally BP, but I have a $15 gift card to burn for Shell

I also use the local grocery store Gasoline, they get theirs form the same refinery BP does and our Grocery store offers 'reward' ($ off up to 15 Gal) for purchases at the store

when i filled the family car on Friday, I got $.45 off per gallon

Re: Gasoline of choice
 

Tear an engine apart that has been running on race gas, and then the same motor with regular pump gas, and the difference will astound you.