RHD RB30 Build - update 6/20/13

Discuss the RB20, RB25 and RB26 series engines.
RRRRB
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I have an RB25 with Rb26 head, I'm running a 6766


J2fast
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RRRRB wrote:I have an RB25 with Rb26 head, I'm running a 6766
Oh I was gonna say how u getting to rev so high. How is that combination? I was going to try it but never got around to it.

RRRRB
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It runs well, spools good and has really came to life over my previous tune at (17-18psi) and pump. Now on 26ish and Pump E85

I Rev it to 8800 to be exact, been solid.. i want to run more boost but it runs well the way it is, and im not anxious to put it on a dyno.

What kinda timing are you running on ethanol, im running 22 degree's at 26psi on pump e85.

J2fast
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RRRRB wrote:It runs well, spools good and has really came to life over my previous tune at (17-18psi) and pump. Now on 26ish and Pump E85

I Rev it to 8800 to be exact, been solid.. i want to run more boost but it runs well the way it is, and im not anxious to put it on a dyno.

What kinda timing are you running on ethanol, im running 22 degree's at 26psi on pump e85.
That's very good results. I'm running low 30 degrees of timing at WOT. What static compression rate are u working with? Aftermarket Hg? What about Pistons?

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chad b.
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30 degrees of timing and 30+pounds of boost........
:whistle:

J2fast
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chad b. wrote:Well that motor won't last long.
well its lasted 2 years before i redid everything. plus the customers cars i tune are very similar and have no issues. its all in how you set it up. if i were higher comp then i wouldn't be so high on timing. but when you have alcohol in you have to add timing b/c the flame is slower.

RRRRB
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I'm running about 7.8 compression ratio.. i have a Cometic .060 head gasket on ARP 11mm studs

Yes the motor is built with weisco shelf pistons and eagle rods.

And to Chad.. how do you know it won't live long... I'm amazed at how much timing my motor wanted.. and I know it wants more.. probably another 3-5 degrees.. OP is running E98 too not E85 like me so the timing isn't unbelievable.. seems aggressive but not unbelievable.. i was originally running 13 degrees at 25psi.. my car wouldn't even Rev out on e85.. it just got to be normal and no knock on 22 degrees.. low timing on ethanol creates high egts and makes for a pre ignition supseptable tune.. E85 is very sensation to preignition.

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chad b.
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Yea man I forgot dude said he was on E98. It's just crazy to hear that much timing with that amount of boost, but it's alcohol, so. We don't have that here, so the tuning methods used with it sound very radical.

RRRRB
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yeah E85 is awesome, turbo spools a bit faster and makes power like or better than C16 for a fraction of the cost. The amount of timing my engine wanted definatly different.. Ive talked to a couple other high powered RB owners that are running around 25-28 degrees of timing on setups simular to mine.. But im not going to push the envelope until its on the dyno and i can see exactly whats going on.

J2fast
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RRRRB wrote:yeah E85 is awesome, turbo spools a bit faster and makes power like or better than C16 for a fraction of the cost. The amount of timing my engine wanted definatly different.. Ive talked to a couple other high powered RB owners that are running around 25-28 degrees of timing on setups simular to mine.. But im not going to push the envelope until its on the dyno and i can see exactly whats going on.
Yea e85 is something else. I love it never use anything else. There's not a lot of pro tuners that really understand how to tune ethanol based fuels.

RRRRB
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What do you mean . I've tuned it like I've tuned everything else..

J2fast
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RRRRB wrote:What do you mean . I've tuned it like I've tuned everything else..
What afr's do you aim for on WOT? Do you have a ethanol content displsy?

RRRRB
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My wot Afr is same as it is for gas.. 12.0 ish I have a full flex fuel setup in my car so yes it will read and compensate for ethanol content.

J2fast
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RRRRB wrote:My wot Afr is same as it is for gas.. 12.0 ish I have a full flex fuel setup in my car so yes it will read and compensate for ethanol content.
Ok so my guide lines are 80-85% 10.2 afr
70-80%= 10.3afr
60-70%= 10.5afr
Below 60-50= 10.8afr

But my rule of thumb is 10.2-10.5 on ethanol winter time 10.5-10.8
Please note you will prob need to add timing. This will also increase tq more than hp so u should feel a diff

RRRRB
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Why so Rich?

J2fast
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RRRRB wrote:Why so Rich?
10.2-10.5 is the range for max hp for e85

RRRRB
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10.2-10.6 I'm assuming your using a gasoline scale.. that's way rich and your just diluting the oil even more than it already gets from ethanol.. from what I've read nobody tunes that rich and going that rich can Induce knock.. explain your reasoning

J2fast
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RRRRB wrote:10.2-10.6 I'm assuming your using a gasoline scale.. that's way rich and your just diluting the oil even more than it already gets from ethanol.. from what I've read nobody tunes that rich and going that rich can Induce knock.. explain your reasoning
well know you getting into my secrets of my success. everything im going to talk about i have already did the conversion of Lambda to gas but from E85. But i must apologize but the AFR i gave was for E98. but E85 is from 10.8 to 11.2. more fuel will not increase knock tho as long as timing is set properly. but the reason why i run that rich on ethanol is in order to obtain or pass the energy level of gas you have to add more fuel (30% more) which in then you will have more energy in the fuel than gas. E85 rich max power is at 10.5 afr with gas is 12.5 afr. both are very different chemicals and should be treated differently as they act differently as well. thats the reason i tune the way i do. i have great success. but like i said i dont believe in treating it like any other fuel. if you ask any tuner does he tune same target on any fuel i would run like hell from him. for instance in one my fuel mixes i have nitro mixed in it, gets very great power i love that stuff but you diff dont want to run that lean are you going to be longing for a new long block.

RRRRB
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The AFR is going to be the same as it would be for gas, as the wideband reads LAMBDA and converts to Gasoline if you have it setup that way, so rich for Gasoline is going to read the same as Rich for E50 E85 or anything inbetween. That being said ive read alot about this fuel and it seems guys are getting results from being a hair leaner on E85 due to the cooler nature of the fuel..

J2fast
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RRRRB wrote:The AFR is going to be the same as it would be for gas, as the wideband reads LAMBDA and converts to Gasoline if you have it setup that way, so rich for Gasoline is going to read the same as Rich for E50 E85 or anything inbetween. That being said ive read alot about this fuel and it seems guys are getting results from being a hair leaner on E85 due to the cooler nature of the fuel..
That's not a true statement. What's rich to gas is not what's rich to ethanol nor e85 nor methanol. It's all diff. Lambda 1. Is 14.7 to gas 1. Lambda to e85 is 9.7 1.lambda is 9.0 for ethanol. But the kicker is each of those has a limit on what is lean/rich and they are all diff.

To be honest I keep my little secrets to myself but I have done nunberous studying and testing on the dyno to see diff on power to see if people that tune like u really right or the chemist that I hired to come up with blends for my business were right. Guess what, the chemist were right.

RRRRB
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what wideband are you using? what are the settings?

J2fast
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RRRRB wrote:what wideband are you using? what are the settings?
Image

so from the chart look at the lambda values, you see stoichiometric for all is 1 that's idle for all 3 fuels, but if you notice they all have different AFR. now look at max rich power for all 3, you notice how they all are different? they are not the same. by nature alcohol is tuned to be richer, that's how it makes that crazy tq. im not saying you cant make good power tuning the normal gas way but you robbing yourself from hidden power b/c its not tuned the way you get the full benefit from using the fuel. that's where that 30% of extra fuel comes into play. 30% more gives ethanol more energy than gas without that its not as powerful as gas.

RRRRB
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30% is already in play even around a gas ratio of 12.0 at 10.5 that's got to be 40%+..

I doubt the torque difference your getting is worthwhile I'm sure other people have tried your method of a ton of fuel and more timing.. but washing down the cylinders and polluting the oil that quickly in a street car isn't worth it..

If it was such a great way it would be done that way.. E85 has been around a while and lots of tuners have played with it surely you and you're chemist haven't reinvented the wheel.

J2fast
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RRRRB wrote:30% is already in play even around a gas ratio of 12.0 at 10.5 that's got to be 40%+..

I doubt the torque difference your getting is worthwhile I'm sure other people have tried your method of a ton of fuel and more timing.. but washing down the cylinders and polluting the oil that quickly in a street car isn't worth it..

If it was such a great way it would be done that way.. E85 has been around a while and lots of tuners have played with it surely you and you're chemist haven't reinvented the wheel.
I'm not reinventing the wheel just going about it the scientific way. But u are washing the walls bc it's getting burned. I have taken my motor apart and inspected it looks very clean. I don't have really bad issues with oil contamination. I did my first go around fix that issue after I took it apart now I'm good.

RRRRB
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Haha ok.. goodluck

RRRRB
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This car still around??

J2fast
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Yes. I'll do an update on it.

I had to find another RB30 block and rebuild all over. I'm waiting for the head to come back then put it back together and see what happens. But I have changed up somethings in the engine setup. Like high compression 11.5:1.

RRRRB
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what happened to the block?

J2fast
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Well I was doing some tuning for a shop and I was needing to upgrade a few things like intercooler and piping. So we exchange some of that for some money off my tuning services and then I ask could change the oil while they are at it. Sure enough before I got home the oil filter came off and the block where the thrust bearing is is unrepairable. So I had to wait to find a block and buy all parts again.

RRRRB
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Man you have had some bad luck with this car! Hopefully it gets back up and running.


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