Can't seem to get enough power out of built RB25DET?

[radianation]

Yes, the local station I fill up at has E85 and that is an option. I seem to have the fuel system and injectors to make it an easy upgrade. It's definitely an option. I'm a little more reluctant to try the water/meth injection because it seems like more of a hassle? Not sure really.

I don't think the exhaust cam has been adjusted tbh, even though I purchased and installed an adjustable cam wheel. When we had some things apart on the dyno we were having spark blowout. This last Saturday when I went back we eliminated the spark blowout by the coilpack upgrade but didn't go back to review the exhaust cam wheel timing. Any tips on that? I would assume the tuner knows this but I'd like to know what we're trying to achieve with the exhaust cam wheel in general so I can better understand how it works. =)

I drive the car all the time. I don't want you guys to feel like it's sitting in the garage all year round for 3 years now. I've done lots of track days and drive it whenever the weather is nice. I just constantly keep tinkering with it because I want it to hit my goals. If the car ran great and was at the power goal I'd be bored and probably buy another car to build lol.

[flatrate]

Most RB's hold torque very well with the mods you have... mine made 412whp on 20psi i had a horrible boost leak so im sure its making a little more now since i fixed that, but it held torque flat as a strap out to 7800 and it horsepower was still climbing...

I have a 3076R

if you have access to E85 you could make a s*** ton of power... just switching to e85 would probably make you and 20-30whp at the same boost level..

I wish i had it here

[nelson8708]

Yes, the local station I fill up at has E85 and that is an option. I seem to have the fuel system and injectors to make it an easy upgrade. It's definitely an option. I'm a little more reluctant to try the water/meth injection because it seems like more of a hassle? Not sure really.

I just suggested meth in case you didn't have local access to e85. I'm not a huge fan of it because if it fails and the car is tuned for the meth then you'll have detonation without it. I would defintally look into making the switch to e85. You're getting to the boost level where you'll need meth inj., e85, or race gas. You will pick up a some power by making the switch and tuning just the fuel map but, once you start to throw some more timing at her is when she will really show her teeth. E85 burns cooler, cleaner, and when burned it creates more gas by volume so you can usually notice quicker spooling. The only down side is access to it but, if you have it local its hard to make a case against e85.

I've had my ka-t running on it and haven't noticed any corrosion...Even stored the car with e85 in the tank and when i went to fire her she fired right up. For fun on the ka-t i'm building right now, i'm going to put meth inj. on top of the e85 and see how much boost i can run on stock timing with out detonation....I'm guessing around 18psi ...If she goes it will give me a reason to put the forged goodies in.

[flatrate]

Meth works great if you spend the time and effort to set it up properly with a failsafe, im making 600 whp and 430wtq on 92 oct pump on my honda..

E85 is still a better option, full race made 750whp on straight e85 on a stock internal rb26

[radianation]

The local gas station not 5 minutes from my house that I fill up at has had E85 on pump for 2 years. It seems like a no brainer then.

Can you give me any tips on how much timing you all would throw at this setup, and if I make the switch to E85 would I need to get a second inline fuel pump or would the walbro 255lph I have support the extra fuel? I think my Denso 850cc injectors would handle the increase since they are only at 60% duty cycle.

[nelson8708]

From what i've read depending on how efficient your engine is a walbro 255 should max out right around 500whp on e85 (basing off honda builds). You might look into getting a twin walbro setup, bosch 044 or 040, and deatschwerks just came out with their own FP that is the size as the walbro 255 but, flows 300lph and is rated for e85. Your injectors should be good for around 600whp on e85 but, you will need a bigger pump. The deatschwerks pump would be the easiest and cheapest option.

As far as timing goes when the car is on the dyno the engine will tell you when its happy. Keep bumping the timing up until you are only seeing a minimal increase in power or hear knock (you would have to run a crap ton of timing to get it to knock though), then dial it back to where you are 3% (tq) below your best pull before you started to see minimal increases. This will leave a nice safe barrier while only giving up a small amount of power. Tuning for MTBT (minimum timing best torque) is the best way imho.

As far as fuel is concerned it seems that running a real rich afr is bad on e85. I've talked to crisspeed on a ethanol forum and he said that when afr's were in the 10:1 range (gas calibrated wideband) that he would see some knock when he first started to tune with it on evo's. The general afr to aim for from what i've read is 11.8:1 but this varies from engine to engine as far as what it will like.

Hope this helps,
-Nelson

[ItzGenX]

Just remember that ethanol has a lower energy value than gasoline. You may be able to get more power out of ethanol (e85 in this case), but you have to spray in higher volumes of it. If your injectors are at 60% duty, then to keep that same power with e85 will put you upwards in the 80%+. By BTU math, it's roughly 30-37% more fuel based on what season blend you use (e85 ethanol % actually ranges between 70-85% by volume depending on the season).

On another note, I been thinking about going E85 when I complete my project too. There has been a station about 7 miles away that's credit card only at an unmanned truck stop for over 5 years. The problem is, that's the only one and would rule out long trips in this ride. If I were ever to take this car on a road trip, the route will have to be adjusted to hit every E85 station on the way and carry filled spare gas jugs in the trunk lol. With the mileage of E85, I may not even make it to the next station.

[nelson8708]

yeah, the down side is access to e85 so if your going on a road trip i would throw the pump gas tune back on. I know a guy here in indy who's g35 is tuned on e85 and he wanted to have some fun at IA so he took a few jugs of e85 with him in case he found some action the pump gas tune couldn't handle. I figured he could up his fuel pressure a bit if his injector duty cycle was a bit high. His 850's should be enough for 500whp. I've seen 500whp with one walbro and 850's on a honda running e85. Thats a total of 3400cc of fuel vs the 6 850's he has which is 5100cc of fuel. The gap between spring and summer blend is 10% (dont think he'll be driving in the winter). That is one of the main reasons you need to leave that safe barrier in the tune. The afr wont change much but if you have the timing tuned on edge for e85 (that is actually 85% ethanol) and you fill up with a tank that is say e78 or so you might have some problems.

[l0nestar]

I used to run Sunoco 94 also, but they changed all of the pumps here as well to 93.
There are only 2 stations that sell E85 here (both Jiffy branded), and consistently MORE than Sunoco 93 or Shell 93 by 15-20c/gal. This is why I keep considering a water / meth kit: Lack of E85/73 stations. I wonder if I could set up a 2nd rom though.. hmm..

Nelson, did you make it down to ToTD?

Sorry for the Jack.

[radianation]

Great feedback. I don't think I would be taking any road trips for pleasure, but doing track events is something I had in mind and I don't currently have a trailer or a vehicle to pull a trailer. This is purely a hobby car at this point and not a daily driver. Are there any issues with doing road racing on E85 and do most tracks have it available like they do race fuel?

[flatrate]

putting in a walbro and a bosch inline 044 inline, yeilded enough fuel flow for a friends car to make 750whp and 575 tq with a 60psi base fuel pressure and 1100 FIC injectors... this was on c16 fuel... that setup should be enough for 650 on e85

[nelson8708]

I used to run Sunoco 94 also, but they changed all of the pumps here as well to 93.
There are only 2 stations that sell E85 here (both Jiffy branded), and consistently MORE than Sunoco 93 or Shell 93 by 15-20c/gal. This is why I keep considering a water / meth kit: Lack of E85/73 stations. I wonder if I could set up a 2nd rom though.. hmm..

Nelson, did you make it down to ToTD?

Sorry for the Jack.

I have 12 stations with in 15 miles of me here in indianapolis, so for me it was a easy choice. I did notice that one of the two sunoco stations around me shut down and the other doesn't offer 94 anymore. During the summer months e85 is on average 30-40c/gallon cheaper than premium around me. I did notice that the gap between e85 and gas prices are not very consistent from one city to another.

I made it to the dragon twice this year with friends but, not to the rb meet. Went a couple months before and then we went 3 weeks after the rb meet. How ever i am glad to say that my buddy i go with on the bikes to ride totd just traded his yukon for a rb25 swapped caged s14 ....The swap is very clean and all stock at the moment but we plan on changing that over winter. He isn't on the forums so i'll probably start a build thread for the car, i'm sure i'll have a few questions since the rb is a completely new route for me. We'll be at the next rb totd meet hopefully with his rb s14 and my kat s13

End thread jack/

[ItzGenX]

Yea hopefully my awd s14 will be on the ground and completely functional by the next totd meet.

Radianation, yea that's what I meant by road trip. I like to attend car and track meets far and wide without trailering my car around. I also would not feel comfortable swapping maps from gas93 to E85 and back to gas on the fly due to the first tank from the switch will be rather dilluted to some extent from what was previously left in the tank throwing numbers all over the place. The only way I would do this is to run a fuel cell with switched power for pump and inline shut off valve with the E85, and the stock tank would be Y-lined with it's own pump and inline shut off valve also. The problem here is that I would have excessive extra weight with all that fuel I carry around lol. The benefit is all I have to do is kill the switch running the current pump with the engine idling until it dies to prevent the fuel return from cross blending into the other tank. Once she stalls, flip the other switch, prime, and good to go. The odds of me using dual tanks is slim though, so I will probably just stick with one or the other full time. If I go E85, I will probably build a decent base map for 93 octane first just in case I find myself on the road without E85 in range. Then after that map is complete, I would drain the tank and refill with E85 and retune for it's own map. That way I can always use the gasoline map as a 'limp mode'.

On the bright side, Haltech is working and experiementing with GM ethanol sensors to work with Platinum Pro ECU's (what I have). If that goes through, then I can pump whatever I want on the fly without even touching the map on the ECU .

[radianation]

Looks like I might try a different turbo instead of upgrade to E85 just yet.

[flatrate]

what turbo?

[radianation]

Possibly Gtx3076R .82

[nelson8708]

that's not a huge jump over the S362 you have on there as far as peak power is concerned. To keep it simple i might just look into a race cover for the s362 and a re-tune. If you're trying to acquire quicker spool then the gtx30 is a good choice. Both the s362 and the gtx30 both flow about the same as a regular 35r.

[flatrate]

The torque was a lot less and was dropping off more gradually in the 388 pull from June. seems like we have more torque now, but the rate of dropoff was a bit quicker. Every dyno chart I've seen shows torque dropping off at higher RPM? I will make sure I degree the cams properly when I put the new valve springs in. Any other tips would be greatly appreciated.

You torque was dropping off in june because boost was dropping off... look at the graphs... those cams need to be degreed

[radianation]

I forgot to update this thread, but here are the dyno charts with GTX3076R .82 turbo:


534 rwhp RACE FUEL @ 25psi


455 rwhp PUMP GAS @ 20psi

[youtube]http://www.youtube.com/watch?v=DRkqY5_hkmE[/youtube]

[RRRRB]

alot more timing and more boost? looks good torque curve very flat

[Detroit.Tee.Tee]

You still here RAD? I have a question for you.