I just ran my personal best today at Dragway 42 in Ohio. 11.87@112. I also ran another best at this track going 13.31@99 on the motor. I was using a 125 shot of Nitrous on the first run. This also did not happen without some kind of failure though. No it was not the motor, as it ran fine considering all the trouble I had to get there today. What happened is that I ripped out the driveshaft and I mean Ripped it out. I tore the driveshaft in half, that's right in half and tore the universal apart in the back so I am not really sure what failed. What I would like to know is what are you using for a driveshaft, is there an aluminum one or just use what you have and use heavy duty universals which is what I think I was using at the time. I also had it balanced at one time. I checked the universals earlyer in the year and they seemed ok and I have not drove the car much this year. But that nitrous...well, it does add a lot of power. What do the big block boys do for this. Here are a few specks on this. 373 gear, No Hop bars, HO Racing set up which includes poly bushings, Higher rate springs, Lowered slightly, Boxed lower control arms, Large sway bar I think it is 1.25or1.50 inches, Adjustable shocks. The front of the car has the same set up also with Heavy springs, Adjustable shocks, large Sway bar, Poly bushings, But you use 1977 Camaro Spindles to get the Disc Brakes and this lowers the car and changes the center of gravity and it handles like a sob. I am also using Mickey Thompson Drag Radials which hook up very good, no, Excellant. But at this track they don't prep it very good so you do spin the wheels once in a while. Mine still tends to kind of hop a little bit when I don't get traction. Usually I just lower the tire pressure a little and that usually takes care of it, but not today. Does anybody have suggestions on this? I have the Shocks adjusted tight on the back and loose on the front of the car. I may need a better set up for the No Hop Bars or none and something else. Any opinions on this? Thanks, Guy.
Congrats on the new best! I am looking at building a similar setup and am also interested in options for strong driveshafts. It might be worth asking the question in the Racing BBB section, just a thought. Goodluck and keep us posted.
Go to Custom Clutch in Cleveland.They are at about 35th and St.Clair.They can build you a mean driveshaft.Look them up in the Yellow pages.
Thanks for the info I will check it out. Looks like the universal failed then the driveshaft must have got caught on the yoke and I think that is what tore it in half.
Shaft shop Henderson Driveline and Axle in Westlake 1-800-829-0411. Sorry I'm partial to them as I built a lot of shafts there from 1991 to 2004. The shop prides itself on building the best driveshafts for the money. :TU: Tim
Thanks for the info. You don't always find places right in your backyard but here's two of them. Yes, I did have a loop on but just on the front. It looks like having one on the back would help also.
Yeah, I put on the loops when my motor was bone stock. I like your combo, it's prety impressive. Looks like you've got the nitrous figuered out, and I'm curious about the nos configeration your using. I'm looking to build a similar combo. Sean.
I used Nitrous Works system. The jetting for my best run as follows. 62 Nitrous jet for the 125 shot, 62 for the Gas jet also. The carb is a 750 dbl pump, the jetting is 72f-80r. I use a 1 inch open plenum spacer. TA intake. I was using 7lbs fuel pressure, I also use a mallory 140 elec. pump with a return line. Bottle pressure-VERY IMPORTANT never over 1050 lbs. I try to hold it at 1000 lbs with a bottle heater. I also used R42T spark plugs. I took 5-6 degrees of timing out also.
Tnanks, I've saved that info in my performance Buick 350 text file. What ignition are you using again?
Great Job, Guy! One tip: Especially since you've installed no hop bars, Check Your Pinion Angle!! The incorrect angle will break parts - just like you've described. It will waste HP as well. What kind of No Hops are you using? If theu are the iron type that relocates the upper control arm up, then good. They are very effective, BUT there is a very good chance that your pinion angle is off. A nice pair of Edelbrock adjustable upper control arms would make the job of setting the angle really easy, and the car will handle even better!
I used to work in a machine shop and did all the drive shaft work there. If your shaft was a stock unit the tubing was .063", and probably 2 3/4" on the ends. I always upgraded a stock shaft to .083 tubing. For any performance use I used 3" tubing .083 wall thickness, for higher horse .095" wall tubing. Spicer u-joints were all that we used. Just a thought for you when you get a new shaft built. Mike
Congrats on the good numbers! How much compression are you running? What is your cranking compression? 5-6 out, what are you currently running for total on motor? How much fuel pressure? What do all the plugs look like? What nitrous kit? I would say you can bump the timing up some and take out some fuel pressure yet. Depends on what your running and the plugs. In some cases, you don't even need to take timing out for a 125 shot. I run my bottle pressure around 925-950. Under 1050 is good.
My comp. is 10.6 My total timing on the motor is 32, I think that I had the Timing at 27 total for the 11.87 run. I did run the fuel pres. @7lbs. My next run was with the fuel press. @6lbs but that is when the driveshaft broke. Maybe that was my 11.79 run. I did have the timing higher at the start of the day but I was having trouble with the motor missing which turned out to be something wrong with the bottle I got from a friend. I had intended to run 2 bottles that day. I put my original bottle on and was ok. I think that if I would have brought the timing back up to maybe to 30 total I may have gotten a 11.50 out of it. The air was the best that I have ever seen it, or lets say the engine breathed it. The plugs seemed to be ok. Comp is 180lbs. sbbuick, Thanks for the tip on the pinion angle, I was thinking about this but never messed with it I am not sure I know how or where to set it at. I do have those iron hop stop bars that mount the upper bars higher. I was looking at those Edelbrock upper bars, looks like a good idea. SS-TRUCK, Thanks for the info on the driveshaft. Do you know where I can find the thicker wall tubing, or would that is something that I can check out at the places that are mentioned in previous posts. :TU:
I would saythe final tuneup you end up with is 5 1/2 - 6 psi and at least 32 degrees timing. 350's have that open chamber that like a bit more timing. I'm surprised your only running 32 degrees on motor instead of 36-38. 180 psi is a good for nitrous in my book. Leaves extra room for extra "Squeezin". With a good hook/60ft :TU: and a little tuning, I would say you could get to 11.40's...as long as your exhaust doesn't hold you back. What are you running for exhaust?? Any carb spacer between the carb and nitrous plate?
1 5/8 TA headers with Jet Hot 2 1/2 exhaust with x pipe 17 inch Flowmasters. The spacer is a 1 inch. The Nitrous plate is 1/2 inch. The air cleaner is a K&N Flowcontrol air cleaner. It is 16 inches in dia. and is 4 inches high with drop base. I had to flip my Nitrous and Gas sylinoids upside down to get everything to fit do you think those being upside down will hurt anything? This engine never liked to go over 32 on the timing. We tried to get it to 36 on the dyno but couldn't so it ended up being at 32. What is really funny is that I had the timing at 27 for the 11.87 run, but before this I was having trouble so I decided to run on just the motor and went 13.31 on the motor with timing at 27 and not my normal 32 and this was the fastest the car went on the motor. o No:
The nitrous would like the 1 3/4" headers and a 3" x-pipe that drops to 2 1/2 after the crossover but you should be able to squeeze 11.60's out of it. The soleniods will be fine upside down. They work in any location. If it runs best with 27-32 degrees timing then something is wrong. Open chamber heads use more timing and your cylinder pressure isn't high enough to justify otherwise. Check TDC against what is shown on the balancer. You can use a piston stop thru the spark plug hole at mark the balancer before and after TDC then split the difference to find the middle which should be Zero degrees. Make sure the piston stop doesn't interfer with the valves. A 125HP shot usually does need much timing out. Or if you have another 350 balancer laying around, pull yours off and compair the 2. It is rare to see one advanced, usually they are retarded and you have to add extra timing. o No:
