basic idea that's helped several members and may help more

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
its almost always a good idea to post the city and state you live in, and
don,t be afraid to ask questions or post pictures,

as there,s at least some chance someone reading about your problem,
or question, that has skills and a desire to help might read these posts that lives near you
!:thumbsup:
one mistake frequently made, is not posting your approximate physical location, someone local to you may know a good shop to suggest or be willing to help personally, someone might have recently had similar issues , so you should at least post the city your located in, when asking advice.
you might luck out and find a helpful mentor within easy driving range willing to help you out or at least get tips on local knowledgeable shops that work on similar cars are reasonable hourly rates, and what dealerships , repair shops, or machine shops in your area, to AVOID LIKE THE PLAGUE:thumbsup:
If you have pictures of your car or project please post those as it helps other members get to see what your working on and get to know you
what might look like a huge insurmountable issue to most newer guys might be something far less complicated to fix by a member with a great deal more experience, and there's lots of things that might take a great deal of typing to explain on the site that take far less effort to show you how to fix or adjust in person, or problems that require use of a tool you might not have or even know exists
I've seen younger guys spend all weekend trying to get some older muscle car up and running, and the problem was basically a lack of experience working on a car that won,t have trouble codes to download and a carburetor vs computer controlled injection, they were familiar with, just knowing how to adjust valves, set timing and use a dwell meter, and tune a carburetor or trouble shoot in general is something that takes time to learn (experience) and a bit of hands on time watching some old geezer can do wonders.
most of us learn from our mistakes, but you get to bye-pass a great deal of aggravation, if you learn from an older mechanic if hes willing to teach or help, some guy who already knows how to avoid making those mistakes because he has the experience, and believe me most of us older geezers made our share, but learned in the process
.\
thats what I started the site for!
to have the more experienced members help as many people learn,
the skills it took most of us decades to acquire,
without needing to spend all that wasted time and AVOID the long expensive process,
of dealing with all the crappy machine shops ,
wasting money on parts and modifications that don,t work,
and waste all that time & money in the process.
I was lucky at times that I had several skilled mentors,
but I also remember making hundreds of stupid mistakes ,
mistakes made simply because I didn,t know better at that time!
and wasting a great deal of my limited cash on junk parts, simply learning what was important and what was trash.
the best bit of advice I can give , is if your in the process of assembling an engine,
or doing some mods to the car,
and you see ANYTHING that looks odd, out of place ,
makes you doubt you did something correctly ,
or you find something does not quite fit,
or you see something just not something you expected,
STOP AND ASK QUESTIONS..,
,,
think things through.... but don't proceed until you know your 100% correct.
DO THE REQUIRED RESEARCH and
don't GO ANY FURTHER UNTIL YOUR CERTAIN YOUR CORRECT

There is a reason why you are asking this question,
ASK YOUR MACHINIST AND VERIFY HIS ANSWERS
the just get a bigger hammer approach is surely the fastest way to get in serious trouble that will cost your a ton of cash and time wasted
http://garage.grumpysperformance.co...ber-of-people-that-don-t-use-resources.12125/


http://garage.grumpysperformance.com/index.php?threads/taking-and-posting-clear-photos.5595/

http://garage.grumpysperformance.co...-the-rabbit-hole-with-alice.10933/#post-66925

 
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Good call! I'm trying to locate my own "old geezers" nearby at the moment, by joining a couple of clubs and trying to make friends... (not as simple as it seems... while my 6 and 4 year olds can make a friend with anyone at the park in a couple of minutes...) :rolleyes:
 
Yes, I've also found that you need to be rather selective in acquiring new "friends", at car shows or the local race track, etc.
its unfortunate but a fact that there's seems to be a small but significant percentage of people that are simply either looking for Help, on their car, and are not likely to return the effort you might spend on their car. and of course the even less pleasant prospect of the few thieves that are just looking to gain access to property they might otherwise never get access too!
I did make several valid , trusted and knowledgeable, older friends at a local monthly car show, over the years,
that dealt, and deals in older muscle car restorations, where the members show off the cars they work on, by joining a club that sponsored the show
 
Hi Grumpy Grease Monkey and members , I like what you're saying about helping other less experienced members. I will be reading a lot of other threads as I go through the site to get a idea of what's what. I'm going to enjoy talking with members on many topics. I'm new at this so I'll do my best to pick up my slack.
Steve from Ottawa,Canada.
 
yes, ideally we can make the personal connections so vital in making this hobby an informative and,interesting spare time pursuit, where we can all benefit from each others skills and experiences, without having to deal with the very few rotten apples in the barrel!
I know only too well from long experience that guys who are ready and willing,
to provide time and effort working on a friends car in exchange for similar time,
spent on their car are (unfortunately) not the majority of people you deal with.
while your never going to find an example of exactly equal time effort and difficulty being exchanged, that's never been the object, the idea is that its supposed to be an on-going mutual exchange of skill's instruction,physical help, and a second opinion or perspective on how to do things, diagnose problems ,time spent, planing changes,upgrades,and solving problems gaining experience, where both members increase skills, time and effort benefiting both members.
one member may be far better at brake jobs and electrical work, those skills can be very valuable one guy might be an experienced welder , body sheet metal worker or milling machine operator, one guy may do paint or upholstery, theres always going to be areas we all are better at and areas we flat out are better off leaving to a more skilled and experience member.
in short finding a dependable and knowledgeable friend in this hobby, you can help and depend on for help, is a huge plus!
 
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  • Welcome new guys! Grumpy is very right bout good friends, there are many times I wish I lived closer to Rick, or he lived closer to me. Both of us would have help on a more consistent basis.
 
Hello I'm new here i live near tampa and have a sbc 350 with an edelbrock xc8 and dual holley 4160-9776 450cfm quad barrel carbs.... i am having a hard time getting this tuned with any reliability at all. Originally sluggish coming off idle and no power really at wot. It was running #48 primary jets with #42 nozzles and standard 30cc accel pump. It now has #70 primary jets and #37 nozzle. No longer sluggish comming off idle but still no power through rpm range advanced timing is set at 36 deg @2500rpm. Any help is appreciated.
 
pictures of your car and engine and throttle linkage will help,
having a return style fuel pressure regulator and testing its working is mandatory,
ALWAYS START WITH THE BASICS AND VERIFY THERES A CONSISTENT
5 PSI FUEL PRESSURE, verify the damper and timing tabs marks your using to set the timing, REFLECT TRUE TDC
THE FLOAT LEVELS IN BOTH CARBS ARE CORRECTLY SET UP, Keep in mind that your effectively dealing with two linked but separate 4 cylinder engines using the same block and crank shaft.
theres no vacuum leaks , and the ignition advance curve starts at about 10 degrees BTDC at idle,verify the linkage must be set up to progressively open ALL the throttle blades fully with both sides being duplicated and timed to open equally ,but consistency from side to side is mandatory, obviously the intake is basically two seperate 4 cylinder intakes melded into one, so each side gfeeds the oposite banks cylinders so everything you do must be consistent,side to side as described in detail in the threads will help, posting a plenum vacuum reading at idle, at 3000rpm and at wide open throttle will help
and smoothly advances to about 36 degrees by about 3200rpm as a start point
XC-8.jpg

posting several sets of clear detailed pictures of your spark plugs, labeled as to cylinder # will help diagnose the tuning issues


read these threads and sub linked info

http://garage.grumpysperformance.com/index.php?threads/dual-quads.444/

http://garage.grumpysperformance.com/index.php?threads/setting-up-your-fuel-system.211/

http://garage.grumpysperformance.com/index.php?threads/carb-tuning-info-and-links.109/

http://garage.grumpysperformance.com/index.php?threads/tuning-a-tunnel-ram-intake.5175/

http://garage.grumpysperformance.com/index.php?threads/holley-carb-power-valves.1639/

http://garage.grumpysperformance.com/index.php?threads/thinking-of-swapping-to-dual-quads.11709/
 
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Floats are set ,barely a trickle out of the bowl when you take the screw out of the side ( carb does not have window)fuel pump has built in 7 psi regulator. its all the way advanced at 2500 now. I had originally just set the intial timing to 10 deg and it didnt want to move at low rpm or wot.vaccum at idle is a hard one to figure out as the xc8 has no manifold vac ports and these particular carbs only have the tuned port for vac advance from the distributor. On that port each carb reads 10psi at idle.i am not sure of the cam that is in it, but it must not be too big if those vac readings are accurate
 
it sounds like the carbs throttle blades are held partly open at idle, I'd suggest you temporarily remove the linkage and adjust each carb separately to verify they carbs are fully close at idle and get each idle air screw consistent at only 1 -1.5 full turns out, if the cars cam is installed correctly and not worn and valves adjusted correctly,the engines idle plenum vacuum should improve.
you can,t assume anything, you verify the basics and work up step by step.
one carburetor feeds each cylinder bank., so each carb must be set up as a duplicate of the other, and it must supply a consistent fuel/air ratio in the correct range over the whole rpm range
Stoich.gif

XC-8.jpg
 
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It did not apear as though they were open. However I failed to mention that it appears as though the previous owner has drilled and tapped for a vacuum port for the brake booster on the drivers side. Im thinking this may be creating an issue during operation as i can get them both to the same pressure at idle but the mixture settings are different on each carb and quite possibly making the a/f ratio off during throttling.On the pic you have as well as anything else ive been able to find on this manifold they all have the throttle spacers with a vac port in them and i cant find any good info on wheter or not that port is original.perhaps you may know
 
If i do that and block off that port i think it will even out the a/f ratio more consistently im going to try that next see how it goes...i'll let you know. Thanks
 
I wish I could be on-location to help tune and diagnose but I'm sure we can help even on only this site answering questions
it always helps if you post your basic location, IE city & state as there is likely to be an experienced member located close to you that can help clear this up!
I know Ive helped several dozen local guys over the years and I'm sure I'm not the only guy willing to help newer guys out either
 
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Ive said this repeatedly, its a damn good idea to post your city and state in your log in info , simply because,
most problems can be found the the cause corrected rather quickly if you don,t assume, anything!
,ALWAYS, drop back to the basics, assume NOTHING, think logoically, test and isolate, and youll very quickly find the problem.
you will likely need to verify ignition timing, verify TDC on the damper and timing tab are correct, verift your getting 13.5 volts or better from the alternator,verify your ignition, advance curve, verify consistent fuel pressure, change the air and fuel filters, verify oil pressure, do a compression test, verify exhaust back pressure at WOT, and post pictures of your spark plugs as a start point
 
Man good advice. I got lucky and found an old grumpy person to help me learn. Learning is a constant ongoing process so new guys if your blessed with having an elder with a lot of knowledge Pay Attention!! Now if my my older mentor could could only show me how to post pictures to this site been trying for 5 yrs!!lol
 
I had a recent email, concerning this thread, it seems that two members who seldom post,
but read the sites posts constantly,(who want to remain anonymous)
recently read a thread where a third younger member was having issues and because,
they found he was located close too their location,
(he was smart enough to list his town & state name)
(they contacted him on facebook, ask a few questions,)
then, they stopped by and helped him install a master cylinder he was having issues with.
a problem that he thought might be major was cleared up in minutes , by experienced members.
Ive constantly seen guys post links too this web-site , so while we may not get the recognition we might deserve , I'm certain the web sites being used, regularly.
you might be amazed at how often someone reading the threads ,
thinks I know how to fix that!I could easily fix that!
but if they have no idea where your located,
they obviously have no idea they might be able to help you out,
or that your local.
(and theres a very good chance you might be great at something that someone else sucks at!
but they might be great at something YOU can,t do worth crap...
thus swapping efforts benefits both parties)


if you check the usage states we generally have less than 15 members on line at any given time but 350-450 non member, visitors and 15-25 robot links in use at any given minute.
 
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