What octane gas are you putting in your Solara?

by **bkp_duke** » Wed Jun 23, 2004 4:21 am

I don't know about the gen2s, but the manual for the V6 gen1's says nothing below 91 octane or you run the risk of knocking. Not sure what it says about the I4s.

I've got a buddy who works at ford in auto design and I asked her if the whole gas octane thing was a rip and she said no, it's actually pretty important for newer cars. Higher octane numbers are required in today's higher compression-ratio engines. The extra heat produced in the combustion chamber from higher octanes is necessary to push the pistons of engines w/ longer stokes (which is all high-compression engines). At lower temps (like when the car is started cold and when lower octane gas is used) the engine's computer attemps to compensate (this is what causes knocking, when the computer notices the bore-stroke is below the expected value at idle RPMs and pushes it up 50-250 rpm to prevent stalling). Lower compression engines (I think the cut-off is below 10.0-9.5:1) don't have these issues because their bore-stroke is shorter and they can use regular unleaded just fine.

Just my 0.02. Each to their own, but my baby never gets anything below 93 octane.

by **Jewls** » Wed Jun 23, 2004 5:34 am

According to the manual for the 2004's, the I4 takes 87 and the V6 takes 91 or 93. I just read it the other day.

by **bkp_duke** » Wed Jun 23, 2004 6:53 am

Yes, they can USE it, but it is not what thg V6 is DESIGNED for. And I bet if you put a diagnostic machine up to the engine it would record several misfires when running on 87/89.

by **angelo** » Wed Jun 23, 2004 8:20 am

TW85 wrote:Use what the engine was designed for.

I use 87, have tried 89 and 93 and have not noticed any increase in performance.

the V6 engine is designed for premium

by **dabuda** » Wed Jun 23, 2004 8:50 am

i use 87...the manual doesnt specify premium

by **erasat** » Wed Jun 23, 2004 8:55 am

It doesn't say that is required, they just mention that is RECOMMENDED, for now I'm using just 87, when prices go down then I maybe go back to 93.

by **alan8888** » Wed Jun 23, 2004 11:36 pm

no matter hows the price go 91 +

I lived in CA some newspaper said the price will reach 3 in summer

by **Jaimster** » Thu Jun 24, 2004 6:00 pm

angelo wrote:
TW85 wrote:Use what the engine was designed for.

I use 87, have tried 89 and 93 and have not noticed any increase in performance.

the V6 engine is designed for premium

Who told you that? Have you ever read your manual?

by **Blacker** » Sun Jul 04, 2004 10:59 pm

My 1998TA has a compression ratio of 10.1:1 and if I use anything under 91 octane, I get knock. The Solara SE Sport is 10.8:1 and I am not risking KR for a few cents more.

by **pythonjosh** » Tue Jul 06, 2004 11:16 am

I've got the V6 and I only use premium 92oct 76 gas. When I got fired from my job I used 87 to save some $$ boy did my Solara get noticeably slower. Never doing that again. Octane is a combustion rating, so the higher octane, the more horsepower (maybe a 1-2hp variation). And since it does cost more, I believe it is cleaner and better too. Sure 87 is good enough, but no way is it better for your car than premium.

by **gogeta** » Tue Jul 06, 2004 4:14 pm

i usually use 89...but last week i used 93 and there was no difference what so ever....

by **Blacker** » Tue Jul 06, 2004 4:55 pm

You may not feel any power difference but, higher octane is more detonation resistant. With higher compression motors and heat of summer, it is easy to detonate. Just because you can hear it, doesn't mean it is not happening. I am nort sure if Toyota is similar to GM but, if the car detects lower octane fuel, it use a less aggressive timing table.

by **Astro** » Wed Jul 07, 2004 10:00 am

I prefer 91. I mostly like the idea of cleaner burning. Isn't it better for your motor in the long run?

What octane gas are you putting in your Solara?

What octane gas are you putting in your Solara?

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