Has anyone else heard of Thompson Performance? I came across them on Facebook a year ago and I've seen almost all of there videos on YouTube. Today I bit the bullet and bought one of there products for my Edelbrock 500. Towards the end of last year my eddy starting have a hiccup when you go full throttle and it's always ran rich. I've never messed with the metering rod or jets. Anyone know the sweet spots to this carb. When I bought it I just adjusted it called it good and left it on there ever since.

 

unfortuately there is no "cookie cutter" group of setting for what your particular engine will like. air/fuel mix needs to be monitored by some form of afr guage. i prefer widebands, myself....but to each their own. A decent vacuum gauge will also help you visually understand what is going on inside your manifold...which will help you see the correlation between vacuum signal, and what the engine needs from your carb. finding the sweet spot will require several test drives and tanks of gas, as well as good, gapped plugs, and the gauges mentioned above.
Having said that, if mileage isn't a huge concern, and you're not too worried about really dialing it all in, follow the adjustment instructions that came with the carb. they'll get a fella close. it will take some time though. also...its not a "set it and forget it" type deal. your tune will need to change with the seasons/weather. the engine will have diffferent demands 5 or 6 months from now, so keep that in mind as well.

I have heard of thompson performance. i really dig the name, as i share the same last name haha! anyhow...i run a plate on one of my quickfuel 450s in a daily driven 4wd truck in NW Montana. I've had it on there for nearly a year...and it DOES make a diffference. My mileage went up 1-2 mpg, and there is little to zero lean bog at tip in, off the line. Was it worth what they charge? I'm still on the fence about that...but the gains definitely are noticeable. There's hundreds, if not thousands, of snake oil/ unicorn teardrop gimmicks for the diy mechanic to make their vehicle the "cat's pajamas," but in my experience, the plate from thompson does work.

 

Yeah I do want to get it dialed in pretty good. I dont drive the truck much anymore it turned from my daily driver to just a summer time truck. Everytime I start it up it smells like fuel and I cant keep it in the garage without the garage having a cloud (not exaggerating) of smoke in there. It fouls up the plugs every year, I checked them yesterday 1,4,5, and 6 were all black with carbon deposits number 4 was by far the worst. Way back when I had a Holley I used wideband to kinda dial it in didn't know the concept of using the wideband and I was 21 years old. Young and dumb. 5 years later I matured up a little bit and know how the things work but dont own one lol! Luckily my brother in law does.

I'm glad it's working for you I was very hesitant on buying the plate. I thought to myself "Well 40 bucks isn't to bad I hope this works for me." Haha!

 

i prefer to use sp435 motorcraft plugs, gapped to 0.055" they seem to do the trick and burn well. just a suggestion.

if you're having hesitations, rough idle, and fouled plugs on only certain cylinders...there may be another issue perhaps. do yourself a favor and perform a dry compression test as a start to get an idea on the internal health of the engine. manual oil pressure checks (other than the guage/light in the cab) in addition to a leakdown test aren't bad ideas either.
certainly not trying to worry you by any means...but its always good to cover the basics first when possible.
how does your timing stack up? how much base timing are you running? do you know how much vacuum it pulls at idle once its warmed up? might there be any vacuum leaks? How long have you ran the eddie 500? are you running a coolant plate under the intake? (may not be a bad idea.)

sorry for the shotgun blast of questions haha. running diagnostics can be good in that you get a much more vivid idea as to what you're dealing with...but it can be a pain too. either way, it's absolutely critical to get things moving in the right direction and really get it running proper.

feel free to post up further findings and/or expand on your predicament. there's a lot of folks here with a collective wealth of knowledge that are willing to provide input.

 

Thanks buddy. No worries I completely understand. I have not done a compression test since I've rebuilt the engine 6 years ago I would love too. I could tell you it pulls 18 to 21 HG at idle when warmed up. I'm not sure what timing is set at either I barely bought the DUI unit and had my friends shop do the work. He said he set at just stock base timing. When it comes to setting timing and adjusting carburetors I usually have a friend that knows help me out because I'm very hesitant to those things but I rebuilt the engine myself how does that work I dont know Haha! I'm just glad it hasn't blown up on me lol. Oh I forgot it idles as smooth as a sewing machine. Really I am surprised on how good it runs.

 

well thats good to hear. certainly a great start!
i'd make sure it has some good fuel, plugs, set the timing, put your gauges in...and run it for a week. try to write down and log afr's during different driving conditions when possible. it'll make carb adjustments easier to track. also keep track of the adjustments that you do make along the way (only one at a time.)
also glad to hear you have some fellas locally to lend a hand. sure does simplify things when starting to tinker on things.
looking forward to hear how things progress!

 

UPDATE: today I installed the powerblast plate and I notice the crisp throttle response 1st and 2nd gear phenomenal 3rd it still coughing a bit but it made it a little better. Cruising it does great with or without the plate but the throttle response is there. I was having a little fun and at stop sign I wound her up and tried launching the truck but she wasnt having it, she fell flat on her face. I immediately pushed the clutch and continued on home.

I have yet to adjust the fuel/air screws.

 

I googled "powerblast plate". I do not understand how they can claim a 5 - 10 hp increase from an accelerator pump accessory. And 15 - 21 from two? What am I missing?

 

The grain of salt...?

 

I dont hold much stock in those numbers either but, it does make a noticeable difference...in my truck. Its a daily driver, so it doesn't spend any time on a dyno or track. it does have better acceleration manners all around though.