Last month I had the privilege of putting my re-rebuilt engine (and the car around it) on the chassis dyno. (I'll update the story in the other thread about it). I wanted to share that with a stock Nailhead, with 93 pump gas, stock carb, stock exhaust manifolds, stock air cleaner, and Petronix ignition it made... drumroll... 200 HP/300 ft lbs of torque at the back tires. I'm super fine with that. It was more of the culmination of all the hard work than trying to set a record. I have NEVER had the car to 110 MPH, and it sounded wicked when they did it on the dyno! Please checkout the video:
Thanks for following up on this, Joe. I hate that you had to go through all you did. It makes me think twice about having my 64 Wildcat's engine rebuilt, which is still running strong. 200/300 ain't bad at the wheels, especially through a TH 400. I'm not an expert and every Dyno is different, but I am thinking that is about 270/370 at the crank bone stock.
203- 306 is close to 265 hp and 395 tq at the crank. never heard someone say hp and tq at mph always at rpms very interesting.
Nice! Dyno video's are a treat.. So glad you got it rebuilt and running again "Finger's Crossed!" and I know it was hard work and waiting.. I like that you did it all plugged up as it would come from the factory. This has a single exhaust if i'm correct? Are the transverse mufflers more restricted? The big TH400 and the double drive shafts I have read can rob 50 hp. and 50 TQ at the least? Wondering if it had true dual exhaust and the air cleaner off what the numbers would be, plus some more tuning.
I thought about all this on the way home. I should have taken my generic air cleaner that just has a filter element sandwich, which is open all the way around, but I was excited. Indeed, only a single exhaust. It has a commodity muffler on it because I literally blew the factory one up. And you are spot on that two driveshafts are pulling the HP/TQ down. Pucker factor was signing the release for the dyno. It literally states that the dyno will stress all parts, used or new, and if the engine/trans/differential blows up, congrats, that's on your dime.
Totally understand stress factor of the dyno.. Blowing up the factory muffler I had mentioned this a while ago to show just how exhaust flow sensitive Nailheads are. Way back in the early early 80's when I bought my 66 GS I also bought these "generic" cheapy mufflers from Autozone which was called something else back when they opened?? I kept putting the mufflers on with just some clamps and had no tail pipes. They kept popping off and dragging with the coat hanger wires I used to support them.. Saved enough money and went to Meineke when they first opened also and they were really cheap with their prices when they opened.. Long story, I got the mufflers tacked on and put 2 inch tail pipes on it.. Before the tail pipes with a posi out back I use to spin these really sticky recap tires maby 15 feet on a hot day. After the tail pipes were added I was lucky to get maby 5 feet. I'm sure the cheap mufflers didn't help.
When I had my 425 rebuilt, I wound up with the same issues as Joe. It just wouldn't make any power. I then had Tom Telesco rebuild it for the second time using his custom pistons and what may be the last factory new 091 cam in captivity. As an aside: many of these 091 cams were removed under warranty as the middle-aged owners didn't like the lumpy idle. It's sorta Buick's version of the old Duntov cams that were popular in the early small-block Chevys. I even heard one story which I cannot vouch for, that Zora Arkus Duntov had a little bit to do with it. In any event, Tom definitely cured the power issue, and years later it still runs great. Moral of the story: Don't let any shop that isn't very familiar with Nailheads do yours.
Cool story! The 091 cam is just used on the dual quad 425 and the high output 401 in the Skylark GS..? These owners had to know what those motors were about when they bought the cars..
