I've been told by a dyno tuner, that he can not tune this motor because of too much over lap, do you guys think that there is anything wrong with this port?

Any comments that are usefull would be

Im wasnt sure where to post this, so mods can move it if they like.

 

Looks great to me. I've seen reputable shops do port work with WAY more overlap than that.

Personally, I close my exhaust pretty much stock, but I do open my intake ports about 10-15* earlier than stock.

 

they couldnt tune it safely because the intake charge was blowing right out the exaust the fuel charge would go by the 02 sensor then ignite so the fuel map was rich but the o2 sensor would show it was lean and there would be a giant cloud of black smoke coming out of the exaust, so they couldnt dyno it safely, then a engine builder stopped by and just by listening to the engine run could tell that there was too much overlap for a turbocharged motor, they said with that kind of port job with that much overlap it optimum for a high output NA motor. so i was pretty much told to build a new motor and that they could pull just as much power out of street port motor as they could a 1/2 bridge and have better idle and it would last longer. So in conclusion if any body has any questions you can contact
1. Ralph at ground zero motorsports (503)256-3278 he dyno tuned or attemted too.
2. Rob at pineapple racing(503)233-3878.He stopped by and listend to the motor. and gave his opinion on it.

I dont consider myself a expert but i consider these two these guys to know what they are talking about and i would HIGHLY reccomend these two. and is where i will be taking my future work to.

 

People run half bridge ported engines in turbocharged apps all day long

 

they said that this paticular motor has to much overlap call them im sure they could explain it to you better then i would be able to

 

Yo dan, did he say how many 1/2 bridge ported motors hes tuned?

Did you make sure to set on the PFC that u installed larger injectors?

 

Dan I don’t disbelieve that you were told any of this stuff but Honestly this is the biggest crock of sh*t I think I have heard in my entire life.... None of what I have read makes any sense to me whatsoever...

I am only a kid but Tuning is the field that I am hoping to go into and have devoted quite a bit of research to, although I am limited in my experiance compared to alot of other people that I hope will post in this thread, maybe at Least I can raise a few Questions that others can answer.

1.) About the motor: Like others that have read this post I have looked at that picture, but I was also present during 90%+ of the build of the motor at Justins and met, spoke with, worked with, and asked questions to the builder. He's a guy with a HUGE amount of experiance & at least at the time worked for Atkins porting motors on a VERY regular basis. There is no Mystery to the ports on that motor that you cannot see from the picture, I think it is very clear to everyone that it is a VERY MILD bridgeport.

2.) If, in the almost non-existant possibility that this motor somehow has way too much overlap, that it was actually dumping a lot of unburnt fuel+air directly into the exhaust, and then igniting, the car would run incredibly poorly, if at all. This is not the case. When the car was running a VERY mildly modified base map on the Power FC (despite all my please to have Justin, aka RX7WEEE get the car tuned), the car ran extremely well. It was very fast and did not have many smoking issues: it smoked a bit on start-up and also a little bit when lifting throttle after heavy throttle, IIRC. If the car is now puffing lots of smoke, then either A) the modifications recently made to the car, such as the fuel pump, fuel pressure settings, or injectors, have been done incorrectly, B) the tuners are somehow either incompetent or being dishonest, because C) there is less then a 00.1% chance that it is a bad motor:

3.) Since it is clear that the engine is a mildly built motor with less overlap then a lot of other motors, it should be able to be tuned easily.

4.) Ground Zero has a good reputation. It makes no sense for them to not be able to tune this motor. I was told that the guy who was going to tune the car has some crazy FD that he tuned and runs a Power FC???? Did the tuner just not want to mess with a unfamiliar motor (somehow he'd never tuned a half bridge or bridgeported motor???) but didn't want to come out and say it??

5.) Is the O2 sensor in question the Wideband 02 sensor that the tuner was using, or the 02 sensor that is stock, in-car?

6.) I am curious as to what type of base mapping that your Tuner did, if any. Justin told me that you installed the injectors and had the fuel system upgraded. Had the Power FC been programmed for the new hardware? Specifically, did the EFI tuner look either on his laptop or the FC commander to see whether the injector type had been correctly set? Did he change the injector pulse width? The FC COMMANDER instruction manual covers how to correctly calculate and set injector data on pages 23-26. If you don’t have a copy, it is available on A’PEXi’s website at http://www.apexi-usa.com/pdfInstallation/12.pdf. One of the possibilities I'm guessing at is due to the recently-installed fuel sys. upgrades the car was running insanely rich and THAT's why there was unburnt fuel in the exhaust.

Even though I don't have answers to alot of the situation going on I hope we can get a good discussion going about this, I'd love to see the car working properly, had a lot of fun & Put a lot of blood (literally) sweat and tears into it, and ever since the motor was rebuilt was screaming "GET IT TUNED" at the top of my lungs....

 

bump for any help??

 

call steve kahn at gotham racing

 

Bump!

 

hey buddy i dont know to much about bridge ports but i know in puerto rico there is a lot of people with turbo bridge ported motors and they are runing hard so you better get a better tuner thats what i said ,go to gotham racing to see if they could help,

 

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<----- port from my commuter car.

10.8:1 under boost, 15:1 under 15" vacuum cruising @ 3500 rpm.
~16-17 mpg, 386 rwhp @12 psi, 400+ (est. undynod) @ 14 psi.
62-1 turbo, 1.15 p-trim
3" exhaust

depending on what your definition of "streetable" is...

 

oh yea, the point....

the port has nothing to do with their inability to tune it. either whoever was trying to tune it didn't know what he was doing, or there was an issue with equipment.

what o2 sensor was being used? the 7057 (vw sensor) seriously doesn't like rotaries and tends to read lean when it gets hot.

maybe it was a problem with your setup?
problem with fuel pump/injectors, etc
maybe the timing wasn't right

there's a zillion things it COULD be, but the port isn't one of them.

 

The port is tunable since I'm making around 700rwhp w/ my 1/2 bridge with a T80 turbo. The only thing you have to know is that a/f ratio won't be as accurate because of the overlap. You usually tune it .5 richer than a SP.