SBC TPI 0411 24X conversioin

[Fast355]

Hi Fast355 Your Marine 395 cam has somewhat similar duration to my cam. I had to remove my intake manifold to swap out the HEI over to the L31 distributor to provide the CPS. the intake ports were heavily stained with fuel/carbon deposits al the way up to the TPI runners. I thought this to be excessive. This past summer, the engine had done a lot of idle tweaking with the OBDI set up. I understand big cammed engines have no business sitting at idle for extended periods of time. I do have a few questions regarding your set-up. - What vehicle is this engine in ? -or going in? - What RPM did you get the idle to settle at? - What have you done to the idle tables to compensate for the false lean condition the O2 sensors would read at idle ? - Are you running open or closed loop when idling? - Does the sequential injection and COP offer any help with a high overlapped cam at idle ? If there are any others who have comments to offer - please do. Thanks in advance. Cheers. Mikey G

It is in a 1997 G1500 Express van.Idle is set at 700 rpm. I only idle it that high because of the 25% underdrive pulleys. Very few changes to the 02 sensor tables. I did have to make some minor changes to the proportional gains due to the long tube tri-y headers. It actually runs slightly lean when you monitor it with a wideband. The plugs stay clean and with the COP running stock .060" plug gaps I have tun it as lean as 17:1 without misfire.Closed loop at idle (I am in closed loop in about 45 seconds)Sequential injection does help because you can set end of injection timing to correspond with cam timing.My cam is relatively small and has no problem idling for long periods of time. I let it idle for about 4 hours straight last winter on a roadtrip to Ohio. Got into a storm and it was crazy cold, pulled off for a few hours and slept a while.

[Mikey G]

Hi Fast355,

Thanks for your responses - well appreciated.

What changes - if any, would you consider if you were using aluminum heads ? like AFR Street 65cc 195s....
Is your WBO2 wired to your PCM ?

I should have the engine/wiring all buttoned up this weekend. I'm not qualified (yet) to do the tuning myself so, I have made arrangements with a local, very well known tuner to remove the VATS and flash in another program. I'm hoping to start the car up and drive over to his shop where he will proceed with the fine tuning on his chassis dyno. This will also include some road tuning time as well. Would you be able to offer any advise for the initial tune so I could expect a start up and limp to his shop?

Thanks in advance

Mikey G

[Mikey G]

Hello All,
Small update. I finished buttoning things up last night. After fixing a pin out issue on the crank sensor it fired up immediately and idled quite well. as soon as the snow dissipates some more, I will go for a road test. IMG_5162[1].jpgIMG_5161[1].jpg

[dave w]

Thanks for the update.

dave w

[Mikey G]

https://www.youtube.com/watch?v=lqdPT1PGZUI

Hello Everyone.

Start-up done went well dyno day was Monday. RWHP was 330hp and RWT was 392ft/lbs

If the link did load

see Youtube - V8 RWD Z24 Dyno Day https://www.youtube.com/watch?v=lqdPT1PGZUI

[evilstuie]

https://www.youtube.com/watch?v=lqdPT1PGZUI

Hello Everyone.

Start-up done went well dyno day was Monday. RWHP was 330hp and RWT was 392ft/lbs

If the link did load

see Youtube - V8 RWD Z24 Dyno Day https://www.youtube.com/watch?v=lqdPT1PGZUI

Did you post the BIN file here?

[Mikey G]

Did you post the BIN file here?

No I didn't.

Purchasing the software and credits was more expensive than having it tuned at my local shop. He had it done in 3 pulls I would still be fiddling with it today... They did load it up in a spare 0411 so I have somewhat of a back-up. There is a wiring issue and only one O2 sensor working. The tuner (BOB), did his best to tune around it for now - idles very low (450rpm) when cold. Fine when warmed up. I had to put the car in storage soon after to take care of moving and some massive renos at the new place. I'm to trouble shoot this wiring issue this winter and return for the balance of the tune in the spring. I hope to leave with a copy of the BIN File.

[evilstuie]

No I didn't.

Purchasing the software and credits was more expensive than having it tuned at my local shop. He had it done in 3 pulls I would still be fiddling with it today... They did load it up in a spare 0411 so I have somewhat of a back-up. There is a wiring issue and only one O2 sensor working. The tuner (BOB), did his best to tune around it for now - idles very low (450rpm) when cold. Fine when warmed up. I had to put the car in storage soon after to take care of moving and some massive renos at the new place. I'm to trouble shoot this wiring issue this winter and return for the balance of the tune in the spring. I hope to leave with a copy of the BIN File.

Oh ok.
I've got a similar issue with mine I think. Left bank O2 sensor goes up and down as it should, the right bank only moves from 0.445 to 0.455, but both fuel trims are working. Let me know if you find a solution to yours. :)

[Mikey G]

Oh ok.
I've got a similar issue with mine I think. Left bank O2 sensor goes up and down as it should, the right bank only moves from 0.445 to 0.455, but both fuel trims are working. Let me know if you find a solution to yours. :)

Interesting. My issue is with the right bank. We swapped the O2 sensors for other known working units and also the wiring from right to left to bank to confirm it was the wiring. We tested the right bank wiring for the usual Gnd, 12v+, signal to the ECM. All were checking our good (???) However, like you, only moving from 0.445 to 0.455 ish.... I wonder if there is something with the ECM..

I will definitely post my findings... Thanks evilstuie :)