My track opens Sunday and I'm wondering if I should run some race gas with my new JWT ECU. I found out a local Citgo gas station has 100 octane unleaded at a credit card pump (how cool). I'm debating on running my typical 92 octane (best you can do in Kansas City) and then some 100 octane. I'm figuring about 4 gallons of 92 and 2 gallons of 100 which should put me around 95 octane overall. I just figured since the ECU uses advanced timing, maybe it could take some advantage of a slightly higher fuel grade. I'd think anything over 95 would probably be worthless and possibly detrimental to performance.

Yay or nay?


Dave

 

I would also like to know...bump

 

The reason for using a higher octane fuel is to reduce or eliminate pre-ignition, detonation or engine knock, whichever you choose to call it.

Unless you have some indication that you are experiencing knock then you would be wasting you money and could even reduce performance by running higher octane fuel.

If you can advance your timing more until the point you get pre-ignition or you can see you timing being pulled back by the knock-sensor then the higher octane would show a performance gain.

Race fuel is mainly used for boosted vehicles which are much more prone to pre-igniton.

 

The new 350z in SCC was tested with 91 and 100 .oct 02 it gained 5rwh 2rwt from just using 100.Our cars will gain from this to,when our cars were made they were meant to run 95 - 100.Its not that the Z gained it just got back the power it was meant to have. USE IT.

 

but i would run all that regular gas out and have a 5-10 gallon gas can full of 100 octane ...and then i would fill up and have it only in the car.. or just fill the car up with it ..and then race ..

 

I doubt JWT advances the timing enough to cause detonation problems. I would think its a waste of money. If anything I'd try to find 94 octane or so...

I used racing gas last year at the track (I think 108 octane) when I was using nitrous, but mainly because I was going to run out of gas otherwise. I did notice the car was quite a bit lighter...oh...wait...that was my wallet. $5/gallon!

 

You won't know until you try it! the worst thing that can happen is you waste a few bucks if it doesn't work. I say go for it

 

Yeah yeah, I know all about octane ratings. Definately good info for those that don't know. I was just concerned since at my track you usually have to wait 1 hour in the lanes to get a run in and the engine and intake manifold usually become baking hot. Seeing how the VQ has reverse-flow cooling (not a great thing), high compression, a sensitive knock sensor, plus I've got advanced timing now, I just wonder if the extra octane might safe guard against any knock and ignition retard. I might give it a shot. JWT requires at least 92 octane.


Dave

 

Rice Gas

 

I'd say don't even bother. Just run 93 if its available.

 

Try going to a hotter plug and running 100 octane. It is known that going to a colder plug would reduce overall power by 5-15hp, so maybe going to a hotter plug with higher octane gas would help? Next time I goto the track I'm going to try out a hotter plug, if it doesn't detonate it might make more power.

 

wont hurt to try, I say give it a shot

 

I think you are going about it the right way trying that. Most people think that higher octane means it burns faster but its just the opposite it burns slower, longer and hotter.

You may come up with a winner for people who want to run N/A and get a bit more HP.

 

interesting on the hotter plug idea...also i concur on what was said earlier about the 350z...they tried race gas and it increaed horsepower, but only for the last 1000rpm or so...

i would say go for it b/c the ecu advances the timing right? i know on the VE brian h said to try race gas when advancing the timing on the VE...maybe itll do u sum good...

 

when i had the Gforce ECU, i always tried to run with octane boosted 91. since in cali, we only have 91 octane...

but yea. the 'leaner' fuel curve at cruise speed takes advantage of the fuel octane and the timing advance..



i take it you went with the JWT ecu over the Gforce ecu out of spite? ha. as long as you're happy with it.. you could have gotten a slightly more aggressive program with GForce..

 

It's all about the raised rev limiter.

I wonder if you could send a G-force ECU into JWT for the raised rev limiter only. Then you would have best of both worlds.

 

I don't know if that would work, it all depends on how they do their programming. If it's just a program flashed onto the ROM then it wouldn't work, because one would overwrite the other. If someone manually goes in and sets the parameters then it would probably work. I think it's probably the former though.

 

The raised rev-limiter was why I went with JWT. That extra 500rpms means everything with the MEVI. I now hit 2nd at 4700rpms and 3rd at 5100rpms. It's just about as ideal as you can get. Talk about no lag in acceleration between the gears (the MEVI without the ECU does this).

Even from 2000-4000rpms, the gains of the ECU are quite apparent. My MEVI 4th gen now drives like it did with the US-spec manifold from 2000-5000rpms (ie very torquey). I especially like the turbo-like surge from 3000-4000rpms


Dave