wide band 02 and egt

[fuzzydoodle]

I didnt find really anything on this exactly. I'm looking to get and egt gauge to help tune but I hear somewhere that you dont need one with wideband 02. That true or no? Or is that only true for 1g's cause they can monitor knock? Also I had different feedback on weather to get a 190 or a 255 fuel pump and rewire. I'm running a fpbt28 with 660's and looking for 21-22 psi...
Thanks for the help.

 

[Talesin]

No, you don't need an EGT if you have a wideband O2. An EGT just tells you if the exhaust gasses are getting too hot... which is usually a sign of too lean or drastically too rich an air/fuel mix. It's a crude way to tune, and leaves you guessing, sometimes with catastrophic results. It also only shows you one cylinder... the only real use for an EGT after you have a WBO2 is if you had one installed on each runner, so you could see if a particular cylinder was having a problem.

You'll likely want larger injectors to handle that boost level, as well as a rewired 255 to give yourself breathing room. The pumps cost the same, and many 2G FPRs can actually handle the higher flow without being overrun. If it does overrun though, an AFPR and install kit can be found for around $200.

 

[fuzzydoodle]

Cool thanks thats what I thought on the egt. Bigger injectors for 22 psi? I hear 550's can handle that no problem... Thats another thing I hear on the fuel pumps people say a 190 with a re-wire could handle 400 hp...? Does anyone know exactly? I just didnt wanna havo to deal with a fpr an the problems of making sure its set right, if a 190 would be more than enough. Thanks again.

 

[Talesin]

I keep forgetting that some people are lucky enough to live in an area with better than 91 craptane. :b
Still, even 94 won't give you too much breathing room though with 550s at 22psi, if it's a decently-flowing turbo. The 660s could do all right, but I would personally be comfortable somewhere around 750 or north.

Some people will outflow their stock FPR with a rewired 190, some people can run their stock FPR on a rewired 255-HP. It's luck of the draw a lot of times, if you got a part manufactured to-spec or if the batch yours came from was slightly off one way or the other. Again, in my mind having more is not a bad thing, and replacing OEM parts (manufactured on the cheap) with race-worthy aftermarket components is never a bad thing.

 

[fuzzydoodle]

Ok. Thats wierd I wonder why a lesser flowing pump would out flow the fpr over a larger one?

 

[Eastwood95]

Think about it. How can EVO's run 20psi all day on a 14v 190 pump and 550's on the 16g and still be rich in the top end? 660's and a 190 rewired is more than enough to run 22psi on a T28.

Get the wideband and forget about the EGT.....

 

[fuzzydoodle]

Cool yeah I was just wondering about the egt cause I was reading somewhere and it mentioned watching the egt's. Already got the uego coming should have been here today...maybe tomorrow. So you think I should just go ahead and get the 190 adn rewire it? I suppose thats true with the evo's but I didnt know they ran that much boost stock.

 

[Talesin]

Differences in OEM part batches, quality control misses, aging, how firmly it's been used, how close it is to failing... there's a lot that can affect the total flow capacity of an FPR. Some people have fluke good-capacity ones (not overruning on a 255HP rewired), some have fluke bad ones (overruning on a 190 non-rewire).

As to Evos, far as I know they don't run 20psi stock. :b And they don't run a 16g, they use a modified turbo with a titanium wheel or some crap to sell it to over-rich individuals.

Yeah, just go with the 190 rewired. Shouldn't be a problem, and you won't get the whiny noise that the 255 puts out. I wanted the 255 so I could be absolutely, positively CERTAIN that I wouldn't have a low injector, or have to re-buy later if I decided to build up much bigger than my current goals. In my opinion, when it comes to your fuel system, there's no harm in having extra unused capacity available.

 

[Eastwood95]

I agree that it's better safe than sorry with the fuel system, but on the other hand, why go that big when you don't need to. Evo's run like 18psi stock, but I've seen a ton of them on the stock fuel system running 20-21psi with a MBC.

Fuzzy, what A/F ratio will you be looking to tune for?

 

[hottboost]

I would get the afpr no matter what pump you use. It will make tuning easier if you ever grow out of the T28. Remember that if you build for the future now then should you decide to go with a bigger turbo you have all of the supporting mods. Also go with the wideband and forget the EGT gauge. Once you master the wideband you should always be able to tune your own car effectively. Everything is a building block for the future. Good luck


Carl

 

[fuzzydoodle]

Thanks, Hottboost. That was the whole reason to pose the question about the fuel pump, I did'nt know if I would wanna go bigger down the line. I suppose i'll push this T28 to the limit then see how it feels. And the question about the egt is cause I just ran across someone talking about it when I was researching afc tuning, an it threw up a red flag... Eastwood, well that was my next question on the tune, I have not had alot of experience with tuning. I got an s-afc2 and started to fiddle. Originally I was gonna take it somewhere and just have them do it, but I think with everything set up and a little experimenting I should be able to handle it. I think i'll do it them take it to a dyno to see how I did. I read your suppose to go by the voltage of the 02...? What should I be watching for? I got it right now to where it seems to run good, don't know the exact mix (still waiting for the damn wideband from map perf.) but I got it set at 17 psi, and I can get up there but I back off @ about 15 or so cause it starts to pull hella timing ( from 33* to about 7-9*)

 

[hottboost]

Thanks, Hottboost. That was the whole reason to pose the question about the fuel pump, I did'nt know if I would wanna go bigger down the line. I suppose i'll push this T28 to the limit then see how it feels. And the question about the egt is cause I just ran across someone talking about it when I was researching afc tuning, an it threw up a red flag... Eastwood, well that was my next question on the tune, I have not had alot of experience with tuning. I got an s-afc2 and started to fiddle. Originally I was gonna take it somewhere and just have them do it, but I think with everything set up and a little experimenting I should be able to handle it. I think i'll do it them take it to a dyno to see how I did. I read your suppose to go by the voltage of the 02...? What should I be watching for? I got it right now to where it seems to run good, don't know the exact mix (still waiting for the damn wideband from map perf.) but I got it set at 17 psi, and I can get up there but I back off @ about 15 or so cause it starts to pull hella timing ( from 33* to about 7-9*)

Here is some helpfull information. Try reading and understanding this material befor you start to tune. http://www.dsmtuners.com/forums/showthread.php?t=58403&highlight=Tuning+guide! Here is another good link. http://www.dsmtuners.com/forums/showthread.php?t=103469&highlight=Tuning+guide. And here is another, http://www.roadraceengineering.com/newafc.htm! I hope these will help you. Let me know how it turns out.

Carl