G20 Van with RV Cam no power on acceleration, where to start?

Hello, I looking for help on where I should&nbsp; start. I am new to tuning and have burned some Bins with adjusted VE and Spark advance tables, but have not yet been able to resolve the issue. I started with Advance Spark table, but did not get any improvement. Then moved to VE and did see improvement when I leaned them out, but still not where it should be.&nbsp;<br><br>I replaced a 350 motor on a 95 G20 Van, with one that was built for by someone else for a pickup project that fell through. 350 bore .060 over with a RV cam ( I don't know the specs) everything is standard 1995 TBI from the van (intake, exhaust, etc).. it starts and idles ok, but starts to cut out around 1600 RPM, and has very little power when driving.&nbsp;<br><ul><li>Vacuum pressure at idle when warm is 16 Pounds</li><li>Fuel Pressure is 12 PSI</li><li>7427 ECU</li><li>PBSA Bin</li><li>$OD XDF&nbsp;(thanks 93V8S10) and ADX (thanks Mark Eagle)</li></ul><br>Any help is appreciated!!<br><br>

base timing set correct? should be zero
possible bad ignition module!

Thanks for the response tririder!!

I have redone the base timing quite a few times, set it at zero, 10 advanced, and currently have it at 5 degrees advanced where it seemed to run the best. Ignition module replaced, still bogs/spits at that 1500 rpm range

Just a thought, with only 12 PSI fuel pressure (and that cam) maybe you're starving it? See if you can get it up higher, maybe 15 plus or, adjust your VE and/or AE tables higher?

The most common thing I have seen over the years is the EGR is still active in the bin file and there is no actual EGR.

Thanks, I appreciate the information.

I have been adjusting the VE, but I did not adjust the AE tables (or turn them off), which could be part of my issues. I have been using this tutorial from EagleMark (excellent stuff!!)when I run the BLM calculator, and update, I think the PE is adding fuel, which is leaning out my BLM data, as the numbers are getting leaner after using the calculator. http://www.gearhead-efi.com/Fuel-Inj...data-Tutorial!

Can a stock pump get more that 13 PSI? Do you recommend updating the pump and the Spring? I will play some more with the VE tables tonight, but am not against upgrading the pump and spring, as they are both orginal as far as I can tell.

Thanks Carl, I set the temp high enough that the EGR should not turn on, but I will double check it.

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Originally Posted by Raymo86

Can a stock pump get more that 13 PSI? Do you recommend updating the pump and the Spring? I will play some more with the VE tables tonight, but am not against upgrading the pump and spring, as they are both orginal as far as I can tell.

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An ACDelco EP381 from a 96 Vortec works well. I have an 18 LB spring that I can run between 15 - 20 LBS. I ordered it with my bored 46mm TB but, I'm sure you can find one on FleaBay or Amazon :thumbsup:
https://www.ebay.com/itm/26451283730...wAAOSw2xRYWVJj

did you set timing with bypass connected or disconnected ?

I didn’t view your log but Make sure your bpw is appropriate for the engine size and injectors used. I’m no expert but as i understand it you need to get the bpw in the ballpark first then start messing with ve and spark.

I Changed the AE so it would not come on and it runs better, still lacks power but better. I have not ordered a new Pump or spring yet. I want to do some more data logging to see if it gets better.

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Originally Posted by WASyL

did you set timing with bypass connected or disconnected ?

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yes, current set at 5 degrees advance.

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Originally Posted by joegreen

I didn’t view your log but Make sure your bpw is appropriate for the engine size and injectors used. I’m no expert but as i understand it you need to get the bpw in the ballpark first then start messing with ve and spark.

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stock 350 with TBI heads, RV cam is the only change.

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Originally Posted by Raymo86

yes, current set at 5 degrees advance.

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Yes for connected or disconnected? Did you changed this in tune also to match?

What are the Air Fuel Ratios from the data log?

dave w

Attachment 17326

Attachment 17327

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Originally Posted by WASyL

Yes for connected or disconnected? Did you changed this in tune also to match?

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My bad. Yes, I disconnected the brown set timing wire (lot easier in the Van then in my 89 pickup) and I did change the tune to match 5 Degrees advanced as well. We are going to get Snow tonight, so not sure I will get the Gvan on the road anytime soon to data log again. I did purchase a new fuel pump like suggested by PlayingWithTBI, and plan to adjust the fuel pressure by following these direction, found link on this site!!. https://www.thirdgen.org/tbi-afpr/ My plan is set it at 14/15 PSI, which should be good for the stock TBI heads the cam, or so I have read.. :geek:

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Originally Posted by dave w

What are the Air Fuel Ratios from the data log?

dave w

Attachment 17326

Attachment 17327

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Dave, I am not sure. I don't currently have Wide band sensor, can I do it without? if not needed, I will do it this afternoon, when I get access to my laptop at home. Thank you for Looking at it!!

I bought a kit from RV Morse Machine, unfortunately he passed away in August, but you s/b able to find one elsewhere. You have to bend down the MAP vacuum tube a little to make it work. The installed pic was when I had a 28LB spring running at 28 PSI :happy:

Edit: I think I had ~$130 all in on this setup.

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Originally Posted by Raymo86

Dave, I am not sure. I don't currently have Wide band sensor, can I do it without? if not needed, I will do it this afternoon, when I get access to my laptop at home. Thank you for Looking at it!!

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Wide Band (AFR) tuning is Optional. Knowing the AFR's for Choke, Warm Up, Acceleration Enrichment, and Power Enrichment is very useful data.

I consider Wide Band tuning more accurate than BLM' tuning.

I posted Wide Band tuning information here: Wide Band O2 (WBO2 Tuning) Spreadsheet (gearhead-efi.com)

dave w

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Originally Posted by PlayingWithTBI

I bought a kit from RV Morse Machine, unfortunately he passed away in August, but you s/b able to find one elsewhere. You have to bend down the MAP vacuum tube a little to make it work. The installed pic was when I had a 28LB spring running at 28 PSI :happy:

Edit: I think I had ~$130 all in on this setup.

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Looks great.. I really like your setup. I purchase a Fuel pressure Adapter I plan on install when I take off the TBI. I thought I would just leave in place. I like adding the gauge like you did however, might go that route as well.

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Originally Posted by dave w

Wide Band (AFR) tuning is Optional. Knowing the AFR's for Choke, Warm Up, Acceleration Enrichment, and Power Enrichment is very useful data.

I consider Wide Band tuning more accurate than BLM' tuning.

I posted Wide Band tuning information here: Wide Band O2 (WBO2 Tuning) Spreadsheet (gearhead-efi.com)

dave w

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Thank Dave. I have downloaded the zip and will study it this week!! I have a Moates AutoProm, is there a O2 Sensor that you recommend using?

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Originally Posted by Raymo86

Thank Dave. I have downloaded the zip and will study it this week!! I have a Moates AutoProm, is there a O2 Sensor that you recommend using?

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I recommend the AEM 30-4110: https://www.aemelectronics.com/produ...uego-afr-gauge

The "WBO2 HACK" for the 16197427 Does Not require the Moates.net AutoProm.

dave w

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Originally Posted by dave w

I recommend the AEM 30-4110: https://www.aemelectronics.com/produ...uego-afr-gauge

The "WBO2 HACK" for the 16197427 Does Not require the Moates.net AutoProm.

dave w

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Thanks Dave! I have read through the documents and have my wire installed in the ECM for the data logging and updated the BIN by changing the EGR as described. Waiting on the Sensor\gauges to arrive. I plan on leaving the original 3 wire O2 sensor connected, as that is what runs the spark advance, unless there is a reason to remove it.

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Originally Posted by Raymo86

Thanks Dave! I have read through the documents and have my wire installed in the ECM for the data logging and updated the BIN by changing the EGR as described. Waiting on the Sensor\gauges to arrive. I plan on leaving the original 3 wire O2 sensor connected, as that is what runs the spark advance, unless there is a reason to remove it.

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Tuning with WBO2 will still require using the original factory 1 Wire or 3 Wire O2 sensor.

WBO2 is basically a measuring tool, like an engine compression tester . . . very useful tools.

dave w

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Originally Posted by dave w

Tuning with WBO2 will still require using the original factory 1 Wire or 3 Wire O2 sensor.

WBO2 is basically a measuring tool, like an engine compression tester . . . very useful tools.

dave w

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Thanks Dave, that makes sense. I need all the tools I can get!! The AEM wide band kit I order came in yesterday. Planning to install this afternoon. I should have everything ready to data log next weekend (weather permitting)!!

Hello, I am missing something, I have been reading this post with focus on installing a wide bad O2 for tuning.

A little more info, I am playing with 95 Chevy truck, so I am pretty sure pin 16 will be the same (for O2 data signal) as van and the zip file calls out. Now if I recall the o2 sensor is a 3 wire? 1 is power and the other ground? does the power need to plug into keyed power source? and ground just to body or is it as simple as run wires to battery with eyelets and disconnect when done?

What is benefit of AEM gauge assembly? does the gauge come with O2 sensor? why not just buy the O2 sensor, seeing the plan is to data log?

I am learning thus my questions.

I tried to edit my post, system would just clock.

So I found the install paper work for the O2 Gauge and it is 4 wire, I have the wiring info, but again why gauge and not just the O2 sensor?

Here's a link to summit for one of the widebands I use. It is Bosch 4.9 sensor(very good) and has a nice 0-5v linear output. Like you I don't use a slow ass gauge but rely on my data acquisition. When tuning I still use the narrow band sensors and weld an extra bung in the exhaust for my wide band, then cap it when done tuning. I generally don't pipe the wideband back to the ecu and use my own datalogging equipment, however, I just did an LT-1 94/95 Lt-1 and piped it through the EGR feedback pin for my 0-5v wideband and it worked nicely without having to hook up all my crapola. Gauges are wayyyyy too slow to do any kind of AE so datalogging is key for most. I do have a super fast analog gauge that I used to use, but shite, just the gauge without and enclosure was over $500 20 years ago and not sure you can even buy it anymore.
For AE tuning you need at least a 25hz sample rate.

I use dataq.com for inexpensive data acquisition. Shoot my first couple units were db9 serial and I want to say only about $25 ea back then. Now they have a nice USB version for $59 and the software is AWESOME. You can tailor it to whatever and name the channels accordingly. It takes a bit of time to set up, but you will never look back :)

Yep, can't edit, new server has big issues :(

Here's a link to summit for one of the widebands I use. https://www.summitracing.com/parts/avm-30-0310 It is Bosch 4.9 sensor(very good) and has a nice 0-5v linear output. Like you I don't use a slow ass gauge but rely on my data acquisition. When tuning I still use the narrow band sensors and weld an extra bung in the exhaust for my wide band, then cap it when done tuning. I generally don't pipe the wideband back to the ecu and use my own datalogging equipment, however, I just did an LT-1 94/95 Lt-1 and piped it through the EGR feedback pin for my 0-5v wideband and it worked nicely without having to hook up all my crapola. Gauges are wayyyyy too slow to do any kind of AE so datalogging is key for most. I do have a super fast analog gauge that I used to use, but shite, just the gauge without and enclosure was over $500 20 years ago and not sure you can even buy it anymore.
For AE tuning you need at least a 25hz sample rate.

I use dataq.com for inexpensive data acquisition. Shoot my first couple units were db9 serial and I want to say only about $25 ea back then. Now they have a nice USB version for $59 and the software is AWESOME. You can tailor it to whatever and name the channels accordingly. It takes a bit of time to set up, but you will never look back :)

I did not double click, has happened twice now. Doesn't bother me, just noting for the admins.

Ok, one more edit :laugh:

Here's a link to summit for one of the widebands I use. https://www.summitracing.com/parts/avm-30-0310 It is Bosch 4.9 sensor(very good) and has a nice 0-5v linear output. Like you I don't use a slow ass gauge but rely on my data acquisition. When tuning I still use the narrow band sensors and weld an extra bung in the exhaust for my wide band, then cap it when done tuning. I generally don't pipe the wideband back to the ecu and use my own datalogging equipment, however, I just did a 94/95 Lt-1 and piped it through the EGR feedback pin for my 0-5v wideband and it worked nicely without having to hook up all my crapola. Gauges are wayyyyy too slow to do any kind of AE so datalogging is key for most. I do have a super fast analog gauge that I used to use, but shite, just the gauge without an enclosure was over $500 20 years ago and not sure you can even buy it anymore.
For AE tuning you need at least a 25hz sample rate.

I use dataq.com for inexpensive data acquisition. Shoot, my first couple units were db9 serial and I want to say only about $25 ea back then. Now they have a nice USB version for $59 and the software is AWESOME. You can tailor it to whatever and name the channels accordingly. Real-time AE with an emulator and watching the wideband and TPS is the shiznit. It takes a bit of time to set up, but you will never look back :)

Well after spending sometime reading and clicking, I think I answered my own question.
The gauge setup Dave reference's seems to be a simple system and the gauge itself is the controller and will convert it as needed to send it to datalogging program in my case TunerPro. Selling with O2 Sensor for about 150 (on Amazon) you can by just the Gauge/controller for about 140 (on Amazon).

The system In-tech referenced looks to offer many additional interface options to provide data to other systems, it sells for about 180 on Amazon.

I think for my basic OBD 1 system best way to go is like Dave calls out, bad part is I will only use this set up while tuning this truck and then don't plan on using it again.

Raymo86 what are your plans with yours when done tuning?

I have no personal experience but seem to read those gauge thingys with external 0-5v do work well. Like you just asked, seems buying one and then re-sell when finished and pay forward kinda. Use it and re-sell...I think we have a buy/sell/trade forum here :D

Sorry to the delay in response. I plan on keeping the 02 Sensor in the Van for awhile anyway. At least until it warms up enough to do some datalogging!!

Quick update: I installed the AEM Wideband a few weeks ago, but it has been too cold here in to do any data logging. I was bored so I updated the fuel pump as suggested by PlayingwithTBI to a ACDelco EP381. Changed the Spring to 14 PSI and modified the TBI to allow more Air. None of this made it run any better, but no worse.. :rolleye: . At Idle it the Air/Fuel is around 10.51, but I haven't had it running much either, as I don't want to open the doors to air it out.

Doesn't look good for any data logging this week as the temps don't look great, but hopefully soon!!!

Thanks,
Ray

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Originally Posted by Raymo86

stock 350 with TBI heads, RV cam is the only change.

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The term RV cam means different things to different folks these days, and for all intent and purposes can be a very large range.
I still crack up every time some one says they have a "3/4 race cam", what is that? LOL
The massive range of camshaft designs in lift and duration, rocket ratios, cam timing offset, etc. make the term "RV cam" obsolete for all intent and purpose when it comes to tuning efi engines.
Just a odd thought that came to mind re-reading this post.
Have a great week. It will be wet, then wet in cold in our neighborhood this week.