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Hey guys, I've got a 1976 Camaro and I was wondering who would be the best person to take my car to so I can get it tuned on a chassis dyno. I live about an hour southwest of downtown Milwaukee, so I would like to keep it in southern Milwaukee area. If you guys have any opinions or know who has the best reputation around, please let me know.
Thanks.
Welcome, I am not too sure about a dyno in your area but do you have any pics?
What's your combo (engine, mods, etc) and level of performance? How's it running right now? IMO, you'll get different answers based on the above answers.
I know bourchardts (south side of milwaukee) has a dyno and will rent out time to let you or a friend or other professional dyno tune it....I'd imagine they'd dyno tune it as well for a fee.
The car has a 350 with a mild cam aftermarket intake, carb, and headers. It runs pretty good now, but I have rebuilt the carb and I have had the distributor out and I'm sure it is not running up to its full potential. Another guy has told me about Borchardts before. Is it a good shop? Yooformula, pics can be seen here:http://www.cardomain.com/id/nasstyz28
Thanks, guys.
Good looking car! I love clean 2nd gen f-bods.
What carb are you running?
What makes you think it's not running up to full potential? What have you done thus far to tune it?
Boarchardt's has a good and bad reputation depending on who you ask. I've never personally had a problem with their work, but then again, I've never asked much from them...and they always have done exactly what I've asked which is what I like. Fast times are also pretty decent for tune ups of the older carbed powered cars. I've always like Kilpatricks' shop based on what others have told me and experienced with their tune-ups, but they tend to be a little pricey.
Of those three, only bourchart's has a dyno though...give them a call and see. Based on your answers above though, maybe I can point you in a different direction to tune it at home.
Thanks for the compliment. I am using a Holley 650 double pumper. The reason I don't think it is running as well as it could is because I can take things apart and put them back together so that it works, but I don't know enough about tuning and I really don't have the tools like an air/fuel guage to check it. Plus I figured on the dyno, there is no question as to whether or not it is making more power.
Wow nice SS too! First LT1 SS I've seen :thumbsup
Well, in all honesty, if you know how to do that, then tunning is cake walk.Quote:
Originally Posted by nasstyz28
Not that I am not saying a trip to the dyno won't prove benifical...but the ideal thing would be to get the car as close as possible and ready for max power tunning....that plus some things about tunning a double pumper can't really be done on a dyno.
The procedure below is the gist of it...it'll give you an idea as to if this is something that you think you can tackle, then go for it...there are more specific reccomendations to which I can help with for getting the max power and driveability.
First things first.
First get the car warmed up, and set the idle speed to it's lowest rpm while maintaining a stable idle.
Grab a vacuum gauge and hook it up to the port at the base of the carb...
With the car warmed up and idling well with the air cleaner on, begin by turning the right front idle mixture screw, while paying attention to the vacuum guage. If the vacuum drops, then turn the other way. If it increases, then keep turning in that direction until it peaks, and then turn it counter clockwise a quarter turn.
You will repeat with the left front, then right rear, and finally left rear...once done, you'll reset the idle speed to as low as you can go while maintaining a stable idle again, then try the idle speed settings again...you shouldn't have any changes, if you do, just repeat the above.
Sometimes you may find that the idle mixture screws have no affect on vacuum, which means you may need to adjust the secondary idle speed screw under the carb base to crack them open a little and lean the mixture out. If this doesn't work, then drilling air bleed holes in the throttle plates is an option as well...these steps are normally only need for large carbs on small engines with big ol' cams...unlikely to be the case with you as a 650 is perfect with a mild 350.
Okay, now this should really make your car much more driveable...but you are not done yet.
The next thing is setting the timing...biggest thing though is to make sure you have the proper curve programed into your distributer. In general, it'll be diffierent for different engines...I am sure that if you know your cam specs and approximate compression ratio, I can find out the proper initial timing for you engine, and the likely ideal timing to, and at what rpm the timing should be advanced by. It's different for diferent CR ratio's, different cams, different heads...but once figured out, it's not hard to get the curve correct, the to set the initial timing.
So now you have the correct idle mixture set, and a properly curved distributer...now on to the jetting.
First off, don't screw up the jetting! Most people do, because they have no idea how the carb works...
1st thing is make sure you write down everything down so that you can put the carb back to stock with no problems...if you screw up, it'll just be easy to go back to what you had.
Then you also need to understand how the carb works...
First, you don't tune for power using the jets...you can, but this is a poor way to do it was the jets are your PRIMARY fuel metering source. This means as you put around, lightly on the throttle, you'll dump in FAR more fuel than is needed.
Instead, on your carb the two things you really want to richen are the power valves, and the jets on the secondary side. To richen the power valve, you need to have your metering block modified...not too difficult. On the secondary side, you MIGHT have a secondary power valve, but I doubt it and will just assume you don't.
So first thing, to tune the primary circut you want to do is to block off your power valve. Why? Well, you want to find out how lean you can go without surging or popping ( signs of running lean). Basically you can start with your current jets and keep going down four sizes. Just cruise around and maintain a steady speed....if there is no surging or popping, try smaller sizes. Once you get surging or popping, go up two jet sizes.
And now, you want to determine which powervalve you need to run...powervalves open at predetermined vacuum levels. For best performance you want the valve to open as soon as possible, so generally you look to have the valve speced to open at around 2-3mmhg below your typical vacuum reading while traveling down the road when reasonably level, or under light acceleration or up slight hills. So if your car sees 13.5mmhg while traveling under these conditions, then a #11.5 powervalve is right for you....
Once this is done, you should have a car that performs ideally...but you haven't gotten peak power yet. For that, then you'll need to either go to the dyno or go to the track. On a dyno, you'll basically want to keep richening the powervalve orifice and secondary jets until you see most power (typically at around a 12.0-12.5 AFR) and at the track, you'll want to keep richening until you see your highest mph, not ET.
With all the changes in the carb, it should run just fine with quick throttle response and effecient cruising...although there is a chance you may have to do some fine tunning with your accelerator pump if you notice any hesitation or stumble with sudden increases in throttle or if pulling away from a stop sign...
...if this feels like something you might want to untertake so as to learn, I'd be glad to lend a hand :thumbsup
Not to hijack, but prince, do ya think a 650dp is to small of a carb for my not as mild 350?
That's not a simple yes or no answer....in short, the 650DP is a good carb for the engine.Quote:
Originally Posted by slow90z
Basically, if this is a light car (3200lbs or less), with steep gearing (3.73 or more), with a manual trans, then a 650DP is a good carb, but you could probably get away with more carb, such as a 750. If it was an auto, a 700DP or 750 vacuum would work well.
But as you know, higher weight, less gearing, differnt trans or low stall converter would change the answer to your question...
If this was a big ol' impala with 3.42 gears and mild converter I'd say stick with a 650, but go with vacuum secondaries.
For the most part, I lean to vacuum secondaries with auto cars, but there are exceptions, again based on weight, gears, and converter.
I can't remeber what trans/gears your car has, but if fuel mileage isn't important, then a 650DP is most likely fine...at worst you are probably only giving up b/w 5 and 15hp. Again, that's at worst on your engine.
One thing I always get though, is the guys who read about dyno test of something like a 400hp 318 that had an 750 or even 850dp on it while on the dyno. They'll point out the good torque at lower and mid rpm's the engine made and what not and assume that the same carb would work fine for them. But the thing is, a dyno doesn't put demands on an engine the way a car, trans, and gears does...and the fact that once a carb throttle is fully open, they basically work well, no matter the size. It's the part throttle, the transition from part-full throttle, and idling that carb sizing becomes important, especially on a smaller engine (which a 350 fits the definition of imo).
Ah, good post. Yeah, the truck should weigh in at about 3500lbs, has a 700R4 being swapped in, and will have 4.56s in the rear with 30" tires.