Here are my Pumpshot values:

TPS:
0.0 - 61
3.1 - 549
6.3 - 732
9.4 - 976
12.5 - 1220
15.6 - 1342
18.8 - 1708
21.9 - 2196
25.0 - 2989

MAP:
0 - 122
20 - 366
40 - 610
60 - 793
80 - 976

I can't really tell if this is too much or too little. Is there a good way to tell. Check my sig for the mods. I also have an open element air cleaner that is not listed.

 

I added in the tables slowly until I felt no hesitation upon pushing the throttle and also monitored the Edelbrock AF meter looking for leaness upon throttle stabs. Too much is no good, I don't think that is too much. Email me at HOTMAIL and I'll email you what I am using. Much more taht that, I think, and I have higher FP.. BUT, engine combo makes a large difference here!!!!!! Especially intake and plenum size.

 

Id avoid messing with the MAP pump shot if i were you. Look at it like the power valve on a carb. In my experience you can get it to where you want with just TPS, with map you add a few variables that can make the car act funny especially if you have a manual tranny like I do

 

Ok

 

You need tto change the "MAP" table if your engine changes make the effect of TPS changes bigger on the MAP levels than they were before the changes, ie, adding 2" TB unit, open plenums/big runners with lots of area compared to OEM.

ie, a change in TPS will create larger MAP changes than before with a 2" TB from the opening that the engine sees being MUCH larger per TPS movement, causeing quicker MAP rises. Both tables work in harmony and both need to be played with.

ie, the tables are ADDED together to get the appropriate pump shot. example, at almost WOT, a 5% tps change wil produce almost no MAP change while at 13% throttle, a 5% tps change will produce a much more pronounced MAP change, needing the extra shot.

A Holley power valve only controls the decision to run the enrichment circuit of the carb, akin to the PE AFR enrichment "circuit" of our TB ECU's. The power valve is vacuum controlled and has NOTHING to do with accelerator pump shot whatsoever in a Holley carb.

 

i didnt say a powervalve had anything to do with a pump shot
like you said a powervalve adds fuel depending on vacuum like uh.. map pump shot maybe and obviously they arent exactly the same if they were i wouldnt have said LIKE i would have said THE SAME THING AS.
Im not in the mood for a whole dissertation on the subject so this time you can take or leave my word for it, you are going to change the TPS pump shot a hell of alot more than the map pump shot to fix his percieved problem otherwise it will still be soggy but make alot of new hissing sounds at low speeds (provided you have an open element)

 

I agree, Pablo. Nice to have you back...

I agree that the MAP table changes will be smaller and more refined but if they are not made and only the TPS change table is used for extra pump shot, you may be severly rich under high TPS and higher %TPS chnage areas, and replacing your rings a lot sooner. Not much, if any, extra pump shot is needed for TPS% changes at the higher Throttle opening settings, ie, small MAP changes. But, If you only changed the one %tps change table, it is a band-aid for the correct fix and you will have VERY rich conditions. You will have as much enrichment fuel pumped at idle stab as at a 75% throttle stab. Not good. That's why GM put in two tables and takes them BOTH into cinsideration when adding pump shot.


I live through it in my trials. Everyone should try this. you'll be MUCH happier with drivability if you spend the time.

 

Could you expand on that? Yes it does make a lot of hissing sounds at low RPM, high load situations.

 

theres always gonna be some and its gonna vary on what you run under the hood, but that hissing sound is the sound of fuel being introduced into the motor for the most part. Like try putting in the numbers from a 454 into your map and tps pump shot tables, there will be a whooooole lot of hisssssssssssssssss sounds as the car stalls itself out on the slightest touch of throttle

 

It's the IAC. Plug it's passage with some High Temp modeling clay OR disconnect it at a low IAC count while warm and idling then, go for a drive, and it will have disappeared. Don't leave it that way, though. Connect it or when it gets cold out, like starting a carbed motor without choke on a below freezing day.

It's the IAC acting like a dashpot. Worse if your VSS is not working. Worse with bigger manifolds. worse with bigger cams... Fun stuff we got.