I removed my old phenolic 4 hole spacer and installed the “Super Sucker” it’s aluminum, pretty heavy compared to the old one. Anyhow driving the car to work this morning I noticed my A/F ratio went from 13.8 or so at 3200 rpm down to 12.2 to 12.8 this is on the highway, engine fully warm, is this typical, running richer with this type of spacer? Throttle response is MUCH better, very sensitive, also the idle lowered to 600 in gear, idle is still Lopey but more stable when cold.
I used to run a 2" with the Dual plane. Had to change to a 1" with the SP3 because of the added height. Mine is a Wilson style. I like them.... Don't you have the qjet style plenum?
Guessing better optimized flow, less turbulence might have left you fat. Did you compare vacuum numbers before and after? Some changes change affect in specific points of operation, and others can affect across the board. (and help explain why two people make the same change on similar builds with very different results. It does not take a big change to do that, but often very small differences, that manifest themselves with greater impact) You may have a stronger vacuum in some places, more efficiency in other places and pulsing that you may or may not have had before. And you may be transferring heat to the carb now, that you did not have before.
I ran 1 on my 455.....I didn't pick up anything over my open.......I also played around and flipped it over one time still no difference in et... But maybe combo didn't need the help it provided
mark, you are a one lucky guy. why, because you are the only one that has to find out how to make this work. nobody else has stepped up to the 350 plate with this issue. damn... you are a lucky guy. lol if you keep progressing with the 350 n/a, you will find out there is nobody to talk to about your thinking. blame keyboard racers. me...been there, done that and continue to fly alone with my 350 builds. i have people tell me i'm wrong and they haven't done what i've done. right now, you are in good company. mart, grumpy fox and me. keep it up, keep looking for the next edge.
That's soerta what Im thinking too, 'course most of my theories don't hold water I AM surprised it made a NOTICEABLE difference, primarily in response, and low end, don't know if it will affect top end at all, the track will tell I did pick up maybe an inch of vacuum.
HAHAHA I checked in the Race 350 section but nothing there. This is like back in the mid 80's when all there was was Kenne Bell and the telephone, or you wrote a letter to them. Oh well, I'll get 'er figured out. Im driving it to work again for the second week, this week with the new spacer, I wanna get some kinda baseline to see if I should lean it out a tad or which way I should go, it is interesting tho!
WOT, I've been wanting to test that BUT, Im having an issue where the secondary pump cam excerts pressure on the pump arm causing the secondaries to stick WOT, they will close, but theres a definite click or snap as the pump arm comes off the cam. If I loosen or remove the secondary cam, they're smooth as silk. So Im not going WOT right now I wanna remedy this issue first.
I've had severally Holley do that try some lubes on cam......I think they make a specific stuff for it......I've use a touch of white lithium
Is the pump arm bent or not riding parallel to the cam o.d.? Bend it slightly to follow the cam. It shouldn't fall off cam.
Mark, here are my 830hp a/f specs for you to compare. jets77/90 idle in park-13.2/13.5 idle in gear-12.2/12.5 cruise-13.9/14.0 wot-12.9/13.1 50cc frt pump-brown cam on #1 30cc rear- pink cam on #1 35 squirters frt & rr Still need more fine tune....
AWESOME! Thanks Ben, Its good to here someone else had this issue and resolved it, I thought it was just me, HAHA. I considered some lube on the cam, but thought " gee, never heard of anybody else with this issue, its just me" Again, this is where us Performance/Race 350 guys need a separate forum
Excellent Mart! Again, if we had a separate forum, blah blah blah Appreciate the numbers for comparison! Right now Im at 80 front 82 rear. My idle in park/drive numbers are similar to yours, maybe a bit fatter now. Cruise is mid 12 high 11's (numbers were similar to yours) tho I NEVER hit 14.0 at cruise. WOT WAS 12.2 to 12.9, haven't gone WOT yet since I discovered the sticking issue, Im afraid too, HAHAHA My idle has dropped to 600 in drive but its stable, meaning it still lopes, but no desire to stall, yah don't have to two foot it. With the lower idle my oil pressure dropped to 10 lbs hot idle, that's cool too it jumps right up so I don't care.