Thanks to the awesome efforts of Mike Phillips and David Wink at Automotive Machine and Performance we got my Nailhead tested! First, I got kind of jealous of Wild Bill since he got his 455 dyno'd, so I asked Mike about testing and he had an opening last Friday 4/18. We got the thing set up by late Friday and broke the cam in...I was nervous as heck about the cam and rockers, but the Telesco's performed perfect and the valvetrain was fine, no serious leaks either :TU: This is a MR code 401- Stock pistons, 0.030 over stock rods, crank W-30-10 cam- installed 4* advanced intake and heads were extrude honed. Heads were prepped by Carmen with the 1.94" intake valve, distributor, flywheel, oil pump, oil pan and pickup all from Carmen. I had a set of GS Club headers with 2.5" collectors bolted on for the test. I left them there @ AMP so Mike is set for future Nailheads. Carb is an Edelbrock 750. had to do lots of carb tuning. best pull went torque 459 @ 3700, HP 373 @ 4700. Then we stuck the Buick X-code aluminum dual quad manifold on there with 2 4bbl Carters- stock dual quads rebuilt by Carmen... best pull went torque 446 @ 3800, HP 377 @ 4700 where it ended, it was leveling off there- stayed at 376.8 @ 5000 rpm. I can't wait to get this into the 65 GS. :laugh: Again, thanks Mike!
Very, very cool. Posting the final jet/rod combo's would be a good future resource for people as a starting point on new engines.
Interesting! Thanks for sharing:beers2: Your power levels are about 35 hp over what Glen's 401 made (that Mike posted last week). Torque is up 16 ft lbs. That looks like a realistic gain, considering your bigger cam, valves, and carburation. I'm still surprised to see peak power at only 4700 rpm. Which of your runs has more power over most of the RPM range, the 1x4 or the 2x4? Hope we get some results from Eriks Dyno run this week. It'll be cool to compare them.:TU: Maybe I'll hit the local chassis dyno this summer for some runs:Brow:
Walt, the torque was awesome. Single 4bbl 455 @ 3500 ( data began collecting at 3500) up to 459 @ 3700 minimal decline from there about 4/100 rpm- @ 4700 still at 417 with 373 hp Average 436lbft and 351 hp Dual quad the thing just sat with the torque @ 444 from 3700 to 4300, ended up @4800 412 and 377 hp. Avg 432 lbft and 349 hp Just a damn fine day:TU:
Thanks to all involved in getting the Nailhead Dyno'ed. It's a tough job and you stepped up to the plate. I do have a question though: You have great roller rockers, a cam, a single 4 BBL, and a 4X2, headers, had the heads and intake cleaned up. Is it me, or does this sound like the numbers are low? Especially going to a 2X4 and having the numbers go down. I guess I don't understand. Given the work and mods to the engine, I'm surprised that HP wasn't over 400, and Torque over 500. There were no pulleys to take away power, no air cleaner restrictions, no exhaust restrictions. Help me out here, what am I over looking? Thanks again for your great efforts this sure was eye opening. Ty
I suspect you will find the answer lies in the fact that the factory overstated the stock numbers. So Ted improved it a lot but he just started futher down than you think. This is not that unusual. You can work backwards from the real 455 stage 1 dyno tape and see that the 430 and 400 engines were likely overrated. 70 Riv 455s were overated while GS 455s and stage 1s were underated with respect to horsepower. Torque is another matter. JW says he has never seen a stock 455 meet the stock factory stock ratings of 510 ft ib. As for the 2 fours intake not doing as well as as single four barrel set up the conventional wisdom is this is not unusual. I think it has to do with the difficult problem of regulating the air fuel mixture among the cylinders due to the complex intake runner lengths.
Jim, I agree with you- I saw a Buick dynomometer test on a stock 401 and the HP was way lower than anybody would ever believe if I wrote it here. Its better to all drink the same kool aid and say the stock HP was 325... I am really happy with the results, plus the engine is ready to drop in and run now :TU:
Ted glad to see you getting closer with the new set up:TU: . I can't wait to see what our set up does on the Dynoo No: . How much was the bill for your dyno time if you don't mind me asking?
The X-Code is a Buick experimental aluminum manifold that Russ Martin had. He sold it on eBay, I was pretty determined to get it! X-Code refers to the number that Buick Engineering put on it- X for eXperimental- Wild Bill has one in his GS Wildcat too. W-30-10 Camshaft.. Carmen Faso Cam doctor analysis-- Buick -401-425 intake & exhaust Lobe center seperation --------------- 109.6 cam degrees valve overlap ------------------------- 13.4 crank degrees Intake valve opening ------------------------- 6.7 btdc lobe center ------------------------- 109.7 atdc Valve closure ------------------------ 45.7 abdc Duration @.050 --------------------- 232.4 crank degrees max cam lift ----------------------- .29149 inches net valve lift---------@ 1.6--------- .46633 inches Lobe area ---------------------------- 24.52 in * deg Exhaust valve opening ------------------------ 45.9 bbdc lobe center --------------------------109.4 btdc Valve closure -------------------------- 6.7 atdc Duration @.050 --------------------- 232.6 crank degrees max cam lift --------------------------- .29094 inches net valve lift---@ 1.6------------------- .46551 inches Lobe area --------------------------- 24.47 in *deg<!-- / message -->
So a stock 63-65 401 was rated 425lbs./ft. 325 HP. In reality it was more like 400/275- sound right?o No: So then getting above the "stock" #'s is a real good improvement.:TU:
Thanks for the great dyno data! I missed the specs on the head/intake clean-up work mentioned in the post above. Will you please provide some detail on the level of intake/head port work? Was the engine balanced and blueprinted (to what extent)? Thx and congrats on your new engine tests! :3gears:
Heads were Extrude honed, competition valve job, ss jet flow undercut valves, resurfaced, intake chamber unshrouded, additional bowl work, hardened ex. seats. Engine was balanced...not sure what contitutes blueprinting so i'll say not on that one.
I think what gives our Nailheads low peak hp numbers is they're maxing at a lower rpm....4700. If these things could breath well up to 6000 rpm, we'd be seeing much bigger numbers. There is a dyno run posted for a hot 350 here: http://www.v8buick.com/showthread.php?t=153248 Note that the 350 heads flow A LOT more air, and it peaked at 348 hp @ 5200. ....Ted still has 30hp on it with the additional 51 cubes. And the Nailheads torque was 60 ft lbs over the 350's ....not too shabby!!!:beers2: Ted, I hope you take this thing down the 1/4....I.m dyin' to see what it'll do!
Like I said, never sell a single 4 set up short. hehe. Cant wait to meet you Ted. Hey , pm your phone no to me and I will give you a call, If you dont mind.
with that 232 cam they moved there power range up 1000 rpm and lost it down low,like you said the nail heads do not make power in the upper rpms. I think you need to keep the power down low.am I wrong?
Using the same cam with a lobe separation of 112*-114* will not have produced much, if any, more Hp or torque, but would have kept the peak numbers for a longer amount of "Usable" RPM's. Gives the engine a much broader torque & HP band of usable RPM's & is more pleasurable to drive in city driving. This has been my experiences anyway.
