I just need some one to tell me...should i go 625 demon or a 600 holley dp??? the demon is starting to frustrate me becuse dialing it in is seeming to take way to long and it seems like we are moving backwards! So i need some one to tell me what to do???
Although it may seen this is the easy way out, it's not. Work with what you've got. Tuning a carb takes all of an hour at best. I don't know what you've got now as far as the engine build or the carb you're frustrated with, but buying another carb more than likely isn't going to satisfy your thirst for results.
Return your existing carb to base line settings(this is why you should keep notes of changes)Or at least put it back to where it was before it started to make you crazy.make one change at a time once you determine what is causing what to happen.Diagnostics can be a bear if you cant get it back to base line.What kind of combo are you running??? Cam/intake/Timing etc...Definitely work with what you have.You will be ahead in the long run.Whats wrong with it anywhoo???
sorry on the delay on the return.......i have a 289 with aluminum gt 40 racing heads, edelbrock torquer intake, new msd ignition, clay smith 302b cam, 36 degrees of timing......the problem was bogging of the line....i have been switching out the jets regularly to see if i was going to find a combo there where i could eliminate the bog, but in the last few days we have found the problem....the secondary spring was way to light. this caused some inconsistency and we all know bracket racing is all about consistentcy. We had one extra spring at the house, so we put that one in and it was alot stiffer and now the secondaries hardly open while going down the strip....i slowed down to 13.20's from the inconsistent 12.55-12.70. I already have the 600 double pumper at my house soo its not an issue of the money. Its more of the issue of what might work better. i keep getting remarks like "why are you still running a vac secondary carb?" so i am unsure of what to do? My next points race isnt for a lil over a month and i need to have car running smoothly by then.
First: bogging off the line will not be cured by a jet change. You need to go up or down on the shooter size to cure that problem. Does the car just bog or does it sneeze? If it just bogs then you need a bigger shooter. You might also need to adjust the pump cam in order to obtain the best transition phase. If it sneezes back through the carb then you need to go to a smaller shooter. Sounds like you need a bigger shooter though. Return the jets to the as-delivered size and work on the shooters. Second: Go back to the lighter spring since secondary opening is not your problem. Third: If you switch to the double pumper you will likely end up with this problem again. However, switching carbs will be determined by your intended usage of this car. Is it a street/strip car or a dedicated race car? Also, what are the numbers on the shooters?
Tweaking the accellerator pump combined with the lighter sec spring will allow the 600 to work.Might just be easier to swap the 50cc pump off the 600DP to the 600VS instead of monkeying around with pump cams and shooters. I always did that mod with a 750VS on my big blocks. But if you're going to just use it as a strip car or weekend cruiser, and aren't worried about fuel consumption, the 600 DP will be the ticket.
alright i think we have decided to give both carbs a shot....i am willing to try the demon out for a race or two more to see if we can get to where we want and if we do i will still switch them out and then get the 600dp running on it and after some trial runs ill see what works the best
I have just set up and put on the 600dp....it seems to be running strong...we were rained out yesterday .....cant wait till next week and then we will decide what one we will conthue with
We got 7 passes last night with the 600dp dropped the 60 from 1.81 to 1.718; 1.715; 1.716; 1.715; 1.710; 1.714; 1.713 tires did not spin a little wrinkle/ and air underneath the front tires... We were running into a stiff headwind but the Goose ran ok 12.62; .60;.59; .58; elims 12.94 on brakes; 12.645 off gas; 12.60 MPH down from previous 107 to 103 (headwind?) the head wind was real extreme we had it set up 37/35 squirters and 74/72 as jetting any more suggestions?? i still think we could get more out of it......without the wind i might have been able to pick up a tenth or a lil more
Wind resistence plays a big part, especially above about 50 mph. I've had a head wind shut down a 400+ hp Peterbuilt truck that would normally top 100 mph, but with a sstiff 20 mph head wind keep it limited to 55 mph. Mavericks aren't the best at this either. Not exactly designed with an aerodynamic front end.
