Need to start using the MSD Box in this thing... but need some help setting up timing using the software or suggestions on overall settings... anything to be aware of ... I know I can go to MSD but they don't know much about Buicks and are reluctant to make suggestions. Car has a 462 cu (Scotty) very similar to John Jr's setup. .. Stage 2 heads (Gessler) ... CSU 850 blowthru.. liquid intercooler... makes about 8 lbs. of boost with current cog on a Vortech V7 YSi Supercharger. Distributor is locked... Timing set to 30..... Hooks well... 3.70 9" locker . Weighs 3850 w/o me.. full interior Has run 9.78 but needs to be dialed in... Set to shift at 6000 with airshifter = Th400 w/reverse man..VB .. has Trans Brake. Have 2-bar map sensor installed Spoke to MSD ... explained how to retard the timing by gear... Gear 1 all timing in Gear 2 took out 10 degrees .. straight line plot Gear 3 took out 5 more degrees .. straight line plot Didn't up load to MSD just playing at this point.... Set Max Rev to 6800 Anyone, familiar enough with the software....? Just want to set this car up for 10.0
Why not add a 2 Bar sensor to the intake manifold and use the Boost Retard Curve? Your manifold pressure varies with rpm and you would get a better result if you vary the timing accordingly. Paul
Hey Paul .... I do have a 2-bar map sensor installed.... can you explain a bit how I might set up the boost retard curve. Just trying to conceptualize how it works.... need a crash course .... where's the idiot book for tuning? LOL
It was 1 AM when I replied. Missed where you had already said you had a 2 bar map sensor. Sorry about that. Was at the track all day. We lost in the final round by .019 First question is: Is this car driven on the street or is it track only? Second question: When you hook your computor to the MSD box, in the upper left hand corner of the graph view screen under "Product Connected" what software version does it show? Paul
So close.... .019!!! darn! Let's just say it's a track car.... the block is half filled and oil temp goes to 240 in 15-20 minutes on the street.. I drive to the car show nearby but can't go much further without shutting down for at least an hour or so... The supercharger (HP) really limits the life of the block ... next step is to pick up the block from Mike at TA and have it built..... In the mean time I just want to have some fun, get used to the car, go to the track and bring it home in one piece.... but also learn a thing or two..... In the upper left hand corner the version number is... 7531 V09 M09
The Boost Retard Curve Graph should show 0-30 for manifold pressure across the top and 0-25 degrees of timing retard down the left side. MSD considers from 0 to 15 psi as manifold vacuum and from 15 to 30 psi as manifold pressure. 1 atmosphere of pressure at sea level is 14.7 psi or 15 psi rounded. So when we talk about boost pressure as 8 lbs, that is above the 14.7 already given to us by nature. We call that guage pressure or what a regular pressure guage would read when connected to the manifold. Typically for racing the graph stays at 0 degrees of retard from 0-15 psi and you begin your boost retard from 0 degrees at 15 psi to whatever you need at max boost. So lets say you need 28 degrees at 8 lbs of boost. You can set the locked timing at 34 degrees and make a straight line on the retard graph from 0 degrees at 15 psi down to 6 degrees at (15 + 8) or 23 psi. It is a good practice to continue the graph line beyond the max boost point to the end of the graph. The higher initial timing will help the engine run a little cooler during run time when the car is not racing and give a better response in first gear when racing. See 1st attached picture Just a side note for this next example: The graph editor will only let you graph from 2 psi and beyond. Now if you want to get creative for street use, the locked timing can be set at 40 degrees initial and you can slope the timing curve from 0 degrees at 2 psi down to 6 degrees at 15 psi, then start the above boost retard curve from that point at 15 psi. This will act as though there is vacuum advance. See 2nd attached picture As always the simpler the better and if if you can keep street driving to a minimum you may not need the last example to keep engine temps low. Paul
Ok...let me try that... seems simple to do... I'll set it up in a bit... Feel like I'm on the right track now.... I appreciate the Tuning 101 approach....helped me to wrap may brain around the idea... I'm sure I'll be back with some questions... Thanks... Chuck
Chuck Just wanted to add this for now: Whatever your final timing is at max boost, the distributor rotor must be phased to the cap at that point. Example: If the timing is 28 degrees at max boost, turn the crank to 28* BTDC and be sure the distributor rotor is pointing directly at the post on the cap. This gives maximum spark when the cylinder pressure is the highest. As you know there is a lot more to this unit including traction control which is why it can't be used in most NHRA sanctioned races. We also need to address using the Step Inputs to control additional timing as well as traction control. You will need to mount switches that are activated by second and third gear to accomplish this. Paul
Hey Paul... You have my attention..... tell me about the switches and where I can order them.... BTW what's under your hood? Chuck
Use an Omron V-15G6-1C26-K You can order from Digi-Key part number SW151-ND. Get some extra. Might as well use 3 switches so you have indication for all 3 gears. Will explain about cars later when I have more time. Paul
Hi chuck Sorry to change gears but I am interested to know about your oil temp. Do you have an oil cooler? Jim
Hey Jim, No oil cooler....half filled block...This is the first block... oil tends to get hot 240 degrees after 15-20 of 30 mph driving..... With a bung in the pan for a sending unit... Have you made any passes? What's your air/fuel ratio? Chuck
Hey Paul... I've attached a document with what's in the car.... couple of typos... I have a Precision Performance Shifter Power Shifter with neutral safety ACD Air Shifter with their programmable computer I'm getting ready to send you the boost curve that's in my MSD... it'll be up shortly.. Why do the curves go all the way to 30? Chuck
Here's the boost curve that's in the car already..... didn't know it was there. Right now the distributor is locked at 30 degrees...
Chuck I'm not sure that I have the whole story up to this point so please bear with me. Have you been running this setup or is this new? If it is new, what have you been using? The graph goes all the way to 30 psi or 15 lbs of boost in case the for some reason the boost increases or you increase the ratio on the supercharger drive. Looked over the build sheets for your car. Very nice job on making sure there are no weak links and lots of attention to looking good. We have used ACD controllers on 3 & 4 speed Lencos as well as TH400s and have never had a problem. I was going to suggest using ACD if you hadn't. I know, I still haven't said anything about what's under my hood. I mainly install all this good stuff on customer's cars and have spent most of my time working on 2000+ HP cars. Will give a longer version later. Paul
PM sent New setup...to some degree...added air shifter/controller.. shifts at 6000... Trans w/brake... new MagnaFuel reg with return line... had fuel pump rebuilt.... New Seat Covers...Rug....LOL! Here are some pix in April... http://www.flickr.com/photos/71buickgs/sets/72157627210152009/
Chuck, Thanks for the info.....we did a block fill too but I have yet to get my heep on the road. Everytime I turn around something takes threes times longer than it should. I hope to have it running in the next two weeks and will keep you posted on A/F readings.
