I would like to see some dyno results for any nailhead. Bill, I know you posted some from a chassis dyno. Is it like hooking up a nailhead to a ch*$# drivetrain? (impossible)(well, nothing is impossible) The only other way to figure power is 1/4 mile times. That is tricky too. Any Ideas?
Some Quarter Mile Nailhead Numbers Below are Bob Quigg's 66 GS Skylark quarter mile numbers and build. The numbers and build are from October 2000. I know he had it apart since then, but I have not heard any new quarter mile numbers. Note the Magnotti heads of Nailhead Porter thread fame. Anyway, here are the numbers: Best run To Date: 11.64 at 115.83 MPH Body: 1966 Gran Sport hardtop, full frame not cut or notched all stock, painted Teal with black interior, all factory glass and window tracks. Only body modifications are a fiberglass hood and front bumper. Race weight with driver is 3,325 pounds Suspension: Factory front suspension, Koni drag adjustable shocks front and rear. South Side Machine upper and lower rear control arms, air bags, factory drum brakes. Wheels/Tires: Weld Wheels all around with Moroso Front Runners and 15 x 9 Hoosier slicks Engine: Buick 401 bored .030 over fully prepped by Bob with blue printed factory oil pump and modified factory pan. Block decked .042, Factory cast crank, factory rod which were polished, stress relieved, piston are TRW forged aluminum 11.5 replacements with .990 tool steel wrist pins. The stroke remains at factory specs. Camshaft: Schneider hydraulic cam advertised intake lift .522 and .544 on the exhaust with 230 duration at .050 and a 108 lobe center. These specs are measure with a 1.6 rocker ratio as Bob is using a 1.4 so the lift is considerably less. Heads: Factory 401 heads cut .010 and extensively ported by Steve Magnotti of Yorktown, NY. 1.55 exhaust valves and 1.875 intake valves installed along with factory stock 1.4 rocker arms. Induction System: Factory gas tank with sump installed, Holley blue pump, all lines opened to 1/2". Edlebrock aluminum dual quad intake with (2) Edlebrock 750 cfm carbs. Ignition System: MSD 6al with HEI distributor. Headers: Custom made with 1 3/4" primary tubes by, "Headers by Ed" in Monroe Ct. Jet-Hot coated. Transmission: Richmond 5 speed manual transmission. Rear: Chevy 12 bolt with Richmond 4.10 and spool I hope to have some Nailhead quarter mile numbers of my own to share with you people this summer. Cheryl
To both, I appreciate the numbers.....but, I've often wondered what numbers would come out of an engine dyno from a freshly built "rock, stock" 401, and also one like this one you've outlined. Did anyone ever do that and publish it? And....I've gotta say this....Hey Specialwagon65....I can't tell you how many times I've accessed the pic's of your wagon and just shaken my head. It is, to me, just outstanding. Nice job.
Ted, My first chassis dyno run barely squeaked past 200 Rear wheel horsepower with a 725 vacuum secondary Holley. Then I added the 800 Q-Jet and played with the timing a little bit and managed to get it up to 220 Rear wheel horsepower. Since then I've added a B hanger and AX rods and a Small body HEI and a Crane PS40 coil and I now run .050 gap on my spark plugs. I expect it would be up around 230 by now - maybe more. I have an mpg of one dyno run which you can view here... http://www.buickstreet.com/video/66electra-dyno1.zip (1Mb) I also have an mpeg of a short burst from cruise down to first and wrenching into second if you want to hear a Nailhead right now. I also have an mp2 of the sound from that video. http://www.buickstreet.com/video/electra-1st-to-2nd-gear.mp2 (250kb) http://www.buickstreet.com/video/electra-1st-to-2nd-gear.mpeg (1.2Mb) A friend of mine just bought a G-Tech Competition meter so I'll be doing some runs (test and tune) this weekend on some deserted back roads outback of town. I'll post the results, I'm hoping for 16's (the car will weigh close to 5,000lbs with both of us in it).
With my stock rocker arms & 180,000+ miles on the motor in my '64 Riv. I had a best of 218.3 HP to the rear wheels. One thing you must keep in mind about rear wheel HP is how it gets there. There is a large loss of HP though a stock drivetrain. As an example, they say that on a turbo 400 you lose 48 HP between the flywheel & output shaft. This is for the '67 up 400's, not the older NailHead 400's which have some more massive parts in them being beginning years tranny's. How much, no one I know of knows. Next is the rear ends on our large cars. If you remove the 8 3/4 rear from lets say a Dodge Dart & install a "Dana 60" because of it's mass you lose 2 tenths. The rear in our large cars are bigger. Lastly, its stated that there is a 10HP loss for each u-joint using a 1 piece shaft. My Riv. has a 2 piece shaft, center support bearing, 2 CV Joints & FIVE U-JOINTS. So, taking this all into consideration 218.3 is not bad. Now with just the addition of my prototype Roller Tip Rockers the rear wheel HP went to 244.9. This is at the rear wheels. Taking into consideration all of the above, this 26.6 HP increase to the rear wheels is quite substantial. Now onto Bob's car. Most of the info is correct. All NailHead cranks are forged, the oil pan is stock, the valve lift is no where near the advertised, (this is what started the Roller Tip Rocker project) the interior is white, the car weighs more because of the addition of a roll bar, plus other little things. With a hurt bottom end, like a 70+ percent leakdown in 3 cylinders, numbers 4-6&8 & 27 percent in number one we had 336.8 HP to the rear wheels. We have been working on getting the bottom end to seal up but haven't gotten it done yet, but have it apart again & are working on it. Our goal is to be in the 10's with a 3400 pound plus car, using 40+ year old technology & still be street driveable to cruises. Well, maybe not as street driveable as some may expect, but you have to give up something.
Kepp us informed As I will be starting my build-up in a few weeks , I will be looking for EXTREME pergormance. Please let me know so that I may clone you.:Brow:
Hey Cheryl! What kind of car are you building? The pics you post look awesome, just wondered if we could get a look at the car all that good stuff is going into? Thanks,
Not What You Think! Well Ted, You asked for it, but it is not so pretty right now! Attached are a few shots of the 66 GS convertible that I am transforming into a four speed. It came with the Nailhead flywheel and bell housing, and that sparked the idea. The original engine was gone, the 65 401 in its place was almost spent, and the ST 300 was whining like a bad dog. I bought a T-10 with linkage, and had it rebuilt. I had a rebuilt 12 bolt with 3.55 gears laying around for the project, and it will receive the 425 in my avatar. Global West springs, front upper A-arms, rear lower control arms and 11" GM disc brakes are also here for the project. It also needed a trunk lid, fender, hood and door - more traipsing across the countryside. The body panels and trunk floor repairs are taking much more time then I thought. It will be a metal-flake burgundy with a black top when finished. The buckets and rear seats have been reupholstered in dove (off-white), and dove interior panels have also been purchased. The 425 started out as test short block for the Gessler heads that I had purchased as part of a package. I wound up buying new pistons, and having it machined and balanced. I talked with more then a few of the Nailhead Gurus, and got some great tips for machining. It has a moderate KB C114A camshaft since the heads and springs were only set up for .500" lift. I also found some good used 66 GS headers, a Quadrajet manifold and rebuilt Quadrajet. The intake set-up even perked up the ailing 401 before it was pulled, and the rest of a 2.5" exhaust system is here for the project. PS: Dont worry, I have long since sured up the back of the car with more support. I would not be under there with that much hanging over me. Cheryl
Cheryl - Does Kenne-Bell still sell Buick parts? Or is that cam something that has been laying around for a long time waiting for a project?
Kenne Bell They are still around! They are more into the V-6 turbo stuff now, but the catalog still has cams and pistons listed for the Nailhead. Phone 909 941-6646 Fax909 944 4883 TECH 909-941-0985 11-12, 1:00 to 4:00 They are in California.
66 Nailhead Dyno Results I had my 401 dyno'd at the shop near Englishtown New Jersey. They have a pretty big setup. At the time, the car was running in the 14.2 second range. Results were: max hp @ around 4750 = 258.7 Max torque @ around 3300 = 349.4 These were rear wheel numbers. As part of the dyno test, I saw that I was running way way way lean (hence detonation) at the high end. I didn't have the proper jets to change at the dyno so later I fattened the secondaries on both carbs from .092 to .098. The car ran happier, no detonation at all, and picked up a little over 3 tenths. I never got back to the dyno after that (about two and a half years ago. Tom Kelly
Excellent! Very good! Engine dyno results are impressive, but rear wheel HP is real to the ground results. I have to find a Chassis Dyno near here! Tom, how is Bob's car coming? Where can we see it race? Thanks for the replies on this thread.
Tom, Thanks for the dyno info! I was curious...what all have you done to yours? Fairly stock? I saw the dual quad note..
66 GS It's fairly stock, 1. Heads cleaned up around the bowls by Greg Gessler 2. Electronic Ignition 3. Dual Carter AFB's jetted for performance with dual K&N filters replacing stock restrictive breather 4. Precision stock exhaust by Eric and Tom Gardner 5. Upgraded gears from 2.93 open to 3.55 posi 6. Upgraded cam to one a little hotter. Still idles smoothly, even with dual quads. 7. BFG Drag Radials 8. Installed switch pitch manual override 9. Gasket matched stock exhaust manifolds That's about it. All of the above improved times from 15.6@89 to 13.82@98.75 Tom
You're right, not really anything radical....nice improvements though. How hard is it / was it to set up and maintain tune on the dual quads? I really like the look and in fact am likely headed that route with a chevy small block I'm building for my '55. And, thanks for the info!
Tuning dual quads It wasn't real hard to get the dual quads set up. I started with the stock rods and jets. I found during the dyno run that the car developed the best hp with the stock breather and the worst hp with the 3X6 inch K&N's with "no filter at all" falling somewhere in the middle. I would have gone with the stock breather (they are beauties) but I noted the A/F ratio with stock breather was normal (about 13.4) while the A/F ratio with the K&N's was 17.3 (way lean) I surmised that this meant that a lot more air was getting into the engine with the K&N's but the jetting couldn't match it. Sure enough, sticking with the K&N's but jumping up the secondary jets from .092 to .098 solved the problem, and eliminated the detonation and finally gave me the 1/4 mile improvement I had been hoping to get from the dual quads. Tom
Another burgundy '66 GS Cheryl, I think you picked some great colors for your convertible project. My thin pillar coupe is burgundy mist with dove interior. It gets a lot of good compliments on the color combo. I really like the looks of that 425 that you'll be putting in it. I've got one also that needs to be redone, along with an ST400 tranny. I will probably want to find another '66 GS to play with though; I don't want to start swapping out stuff on my numbers matching car! Looking forward to seeing the final results! Steve
Motivation Steve, Do you have any pictures of your car, inside and out, that you could post? I think I could use a little motivational therapy. I get tired just looking at it on some nights! Thanks Cheryl
pics for Cheryl Cheryl, Kinda hate to post these on this dyno thread, but since you asked I'll post a couple. However, it shows like your project is well planned and thought out. But I know execution does take time and money, often a lot slower process than we like somtimes. But the end result will be well worth it when you take the first ride in it! Here is an exterior pic. I'll have to post the interior pic separately since I can't seem to attach more that one pic at a time. If you want any other pics, just send me a PM so I can send them directly to you. Steve
