octane rating for sr20

[SET240SX]

Any of you guys run high octane (110+) or know how the sr would react to octane #'s this high?

I would not think it would be harmful since higher octane ratings help prevent detonations.

[SET240SX]

Come on help me out here. I am serious. I know somebody in here knows where to get high octane gas besides me. I just need to know how the sr20 will handle it.

The more i think about it, I am think 20psi boost 10.5-1 pistons 115 octane should make some good power without getting into det troubles.

I know alot of you are going know way anybody could buy that kind of octane gas but yes it is available. If i learn that it is indeed not harmful to the sr i can let everyone know where to get it. I will not do so until then. I don't want to be responsible for a lot of people cratering engines or turbos because of one of my posts.

THXany info will be appreciated

[BuudWeizErr]

I don't really understand your second post, but maybe this will help.

In Vegas, all the 76's have 100 octane, and it's like 3.99/gallon. At the drag strip in Vegas, one of my friends got leaded 107, but he was running a testpipe. I think that cost him like 5.00/gallon.

SR's C/R is 8.5:1, I don't know where you got that 10.5:1 number, maybe I'm not understanding.

[Nathan]

I think he might be talking about building a more race oriented motor (ie: building it with high compression pistons) Personally, I dont think anyone on here has a need to do such things, just upgrade the turbo and run higher boost (well and do all the accompanying modifications) Also, you will not see any boost in hp unless you are allready encountering detonation and the ECU is retarding timing because of it...if you arent having detonation issues then the higher octane rating is just costing you money and is pointless. The higher octane is not going to hurt the engine to the best of my knowledge, just make sure you actually NEED to run octane this high...there are SR's making over 400hp on pumpgas so it can be done without 110 octane gasoline

[SET240SX]

Thx for the posts.And yes nathan i am building a race motor. Changeing pistons anyway so why not up the compression as long as i dont get into detonation trouble. Therefore was wondering if anybody had any info.

[ItzGenX]

10.5:1 is rather high, even for a race motor. Most run anywhere between 8.5-9.5:1 compression. I am personally leaning towards 9:1. Its not too much where there motor will explode and not too little. Stock compression is actually closer to 8.3:1 then 8.5:1.

[Nathan]

Set240sx...thats what I was kinda thinking you were doing I guess you wont have to run as much boost, I'll be interested to see how it works out for you! I would never build an engine like that for daily driving but for racing well now I understand. I notice your from Texas, what part?

[solid]

what is the minium requirment for a sr?

[pampadori]

The sr20det can be run with 89 octane safely. it can also be run with 110 octane. btw, the jdm sr20de had 10:1. the usdm had 9.5:1. we have run 15psi on a jdm motor in a b13 with good results. you should feel the b13 we have with high compression and just a t25 turbo. no lag what so ever.and it runs 7.7 1/8th miles! cool little car.shaun

[SET240SX]

Nathan I am from south east texas Beaumont area. Also i was thinking the same way less boost but more compression to make the power. Comes from my mustang building days.

Genx I ended up with 9:1 pistons. They were available and through my research i didnt find a alot about sr's running high compression. But then again i didnt find a lot of people running high octane to control any detonation problems. In other words i chickened-out this time. lol

After i get this engine tuned and some #'s i may play around with different compressions.