And really you could wait for budget later and put a new top end on the motor. Same cam and all with aluminum with smaller chambers that bump compression and will outflow the irons to get closer to 450 HP And 535 torque. So not to hard just a matter if ya want to or not. But over 500 ft lbs of torque will keep you grinning.
Well JW did a sbb 350/.030" over(355) with the TA 212 sbb version of that cam with ported heads that flowed about the same on the intake around 250 CFM, that build made 350HP/400lbs of torque! A 455/.030" over is a 462 if I recall correctly so 107 more cid should be a bit more than 367/450! I would say about 420 HP and 542lbs feet of torque is my guess. GL Derek
Not as bad as you might think. Yes, you will have less off-the-line acceleration, BUT since you will be staying in 1st gear longer (maybe 50MPH instead of 40MPH), you will get back almost all of the acceleration that you lost off the line. Same with your 2-3 shift (although you will probably finish the 1/4 mile in 2nd gear, which is an advantage IMO). I've driven tall gears forever and it's not nearly as bad as people will have you think... plus the car becomes a dream on the street/highway (where I put on 99% of my miles). If you get all worried about your 60' time, I think you'll be spending a lot of money on something with barely any gain and costing yourself a lot of drivability. In my opinion, the loss of about 0.15 seconds in the 1/4 mile is TOTALLY worth the rest of the driving experience to keep the tall gears. (And besides, if you are doing 70MPH down the freeway and see a Mustang, it's a thrill to be able to downshift into 2nd and blast into the 3-digit MPH range without thinking twice) [insert safety disclaimer here] Build for torque, not for HP. -Bob C.
Those pulls were with their house carb. They just installed my qjet to make sure it's working properly.
Congratulations!! You just put my dream together.. those figures in a 76 4 door. Beautiful. Hope she gives you years and years of joy! Really look forward to hearing your opinions once its in the car. You've literally doubled the hp!
Thanks!!! I'll keep things updated as the installation happens. I told the mechanic I'll be delivering the motor tomorrow. I have vids that I'll upload later as well.
Bob, Thank you for this post. It really helps keeps things in perspective. Can't wait to get back on the road!
That looks like the torque curve is nice and flat. That's the best way to go. BTW We're finishing up a '73 LeSabre, the big cars are tons of fun with so much torque. -BC
How many pulls did you make and was there any break in before the dyno? I am wondering if the gains are more because the rings are starting the break in? The BSFC's are real high on that last pull.
We did a total of 4 pulls. The cam break-in lasted for about 20 minutes. The engine ran with the RPMs held mainly around 2100, with some deliberate fluctuations. During that time, we/they monitored oil temps. When the oil temps plateaued, then dropped a few degrees, they shut the engine off. We/they drained the oil (Brad Penn, with extra zinc additive added), then inspected the filter. Everything looked normal, so the filter was cleaned, reinstalled, and the oil was added in prep for the dyno pulls. The first pulls were using their carb. They use their own carb for their initial dyno runs. I asked why, and they do this because they know it works, and reduces the chance of having problems getting the engine to run right during those first critical moments. The last two pulls were with my qjet. The first pull with my qjet showed a significant drop in power. It measured in around 363hp/4XX tq. We changed the rods in the carb to allow more fuel, then we were back in business.
Can you post all 4 dyno sheets? That last pull on your video is way too fat. I didn't look at your build to see what rings etc you used but as the rings start to seal the power will pick up.
I only kept the final dyno sheet. When I go up there today, I'll see if I can get a print out of the others. Can you help me understand your term "way too fat"? I looked up BSFC, and have a basic idea, but sometimes a "real world" paraphrase/explanation can clear things up so I can better understand...