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-   -   BBC 509cid tunnel ram efi build. (https://www.offshoreonly.com/forums/general-q/381984-bbc-509cid-tunnel-ram-efi-build.html)

JaniH 04-27-2024 11:41 AM


Originally Posted by Rookie (Post 4896669)
Yes, that is JimV's old intake. It was on his old 27' Fountain. He now runs Single plane throttle body injection on his 38' Fountain.

Did you use IAC for idle correction?

Rookie 04-27-2024 06:18 PM


Originally Posted by JaniH (Post 4896672)
Did you use IAC for idle correction?

Yes, I use IAC in conjunction with timing. I found that timing is faster than what the IAC can react. In gear I would stall often until I redid my idle timing tables.

JaniH 04-28-2024 06:11 AM


Originally Posted by Rookie (Post 4896693)
Yes, I use IAC in conjunction with timing. I found that timing is faster than what the IAC can react. In gear I would stall often until I redid my idle timing tables.

Would be awsome to get base tables for ignition and fuel, but at this point i have a long way to tuning 🙂. My ecu does not have the driver for gm style 4pin stepper motor, so i am going to use the bosch 2pin fir 19mm hose.

JaniH 04-28-2024 06:18 AM

36-1 Trigger wheel is ready for some paint.
Trying to find cost effective Bbc bracket for crank sensor, cherry Hall sensor.

https://cimg8.ibsrv.net/gimg/www.off...522b7485cf.jpg
https://cimg9.ibsrv.net/gimg/www.off...1f87a06803.jpg

Rookie 04-28-2024 09:19 PM


Originally Posted by JaniH (Post 4896712)
Would be awsome to get base tables for ignition and fuel, but at this point i have a long way to tuning 🙂. My ecu does not have the driver for gm style 4pin stepper motor, so i am going to use the bosch 2pin fir 19mm hose.

I Didn't do much with my fuel at idle. I believe I'm around 13.5 AFR target. When warm my IAC runs at about 0-2%. The key is adjust the throttle blades so it does not need to use IAC at idle. (calibrate TPS after adjusting blades) I have my timing at 36° from 0-1000 RPM (target idle 800 RPM) and I allow idle stabilization timing to throw +/-8° timing to catch the engine at in gear transition with the help of the IAC to open +98% if need to stabilize the idle. I also have the IAC set to fast react.

JaniH 04-29-2024 04:04 PM

What you think about the valve stem clearances for N/A, closed cooling, is 0.0017" int, 0.002" exh ok?

Rookie 05-03-2024 11:09 PM


Originally Posted by GPM (Post 4894361)
In my opinion and from trial and error, less than 8 degrees of split didn't work that well on N/A or blown BBC


Originally Posted by sutphen 30 (Post 4894872)
will be interesting to see how that 5° split does for power.

Look what just appeared in my Youtube suggestions...


JaniH 05-04-2024 12:12 AM


Originally Posted by Rookie (Post 4897222)
Look what just appeared in my Youtube suggestions...

https://www.youtube.com/watch?v=nEoGwr90SPk&t=646s

Interesting, i quess the results would be different with marine exhaust manifolds vs those good flowing headers. I would never add 16 degrees duratiton to gain 10hp, when reversion and valvetrain stability is a concern. I think that the marine manifolds benefits more from the larger duration split.

sutphen 30 05-04-2024 01:04 PM


Originally Posted by JaniH (Post 4896845)
What you think about the valve stem clearances for N/A, closed cooling, is 0.0017" int, 0.002" exh ok?

thats fine,good valve seals will control the oil

GPM 05-04-2024 02:39 PM


Originally Posted by Rookie (Post 4897222)
Look what just appeared in my Youtube suggestions...

https://www.youtube.com/watch?v=nEoGwr90SPk&t=646s

I would bet different engine combinations would react differently, but it was a good video.


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