The good old days and 4.10's! You're going to need a fresh set of tires by now. Go with a set of M/T Drag Radials. They'll hook better than what you had and be worth a mph or so. That will solve a lot of traction problems. My '65 pulled strong to 5-5200 at the track and it had the stock cam. The stock cams were even dual pattern so that is the way to go. The cam you have deserves to be shifted higher but if you still have the stock unported heads they could be holding you back at a rpm much above 5200. The smaller dual pattern cams will pull much harder to 5000 just as shown in the curves and pack in more lowend and midrange punch. Your current cam only gets to shine for the few seconds it is pulling hard at the traps. I think Crower will make up custom Nailhead cams. The Comp 279 Thumpr cam might be worth looking into if you want a rougher idle. I'd stay conservative on the cam because as can be seen the milder cams are packing a larger punch down low. The bigger cam comes on strong at high rpm but then the heads cut it off so you don't pick up anything going bigger on the cam. The TA 25 might be the hot item if you are not going to hog out the heads. I'd say you could probably get away with less gear and run just as fast with that cam. If you stay with the current cam get the smaller converter, better tires, and consider some headwork to allow that baby to breathe at higher rpm. The rockers are an added expense right now that would only pay off at higher rpm which is what you don't need right now. If you can't/won't shift higher than 5200 a bigger effective cam with the rollers won't show anything. Whatever you do let's get that baby back out into the sunshine of a dragstrip! I think this is you at E-Town 1990:
Thanks for your insight Mike. You certainly know how to get the most out of a combo on the strip. What times did your '65 run with the Nailhead? When I first met you, you had already converted to a 455..... and that was what, 33 years ago?? LOL! When I bought my Isky cam in 1977, I told the Speed-shop guy I wanted to run 12's and this is what he gave me. It's amazing to see how technology has changed since then. Joe is using one of the dual profile 'hybrid' cams and is in the 12's.... proof that the newer tech works. Bob, those Comp grinds I used in the sims are on a 110 lobe center. I basically copied Comp's Olds (1.6 rocker ratio) Extreme grinds and stepped up to the next larger exhaust lobe. I call them 'hybrid' grinds since they combine lobes from different cams.
Walt, maybe advancing the cam 4* to give it a 104* center line, give you more bottom plus more cylinder pressure too and smoother idle. a better 60 ft time and higher shift points you will be closing in on the 12s. a set of roller rockers you would be there for sure. its for sure a healthy sounding motor.
I agree with GSGTX on trying advancing your cam if it isn't already for the same reasons. Back then there's a good chance that it isn't even degreed in. Maybe it is even retarded a bit. The higher shift point would help also but then the heads come into play. Do you have a carb spacer on it? I'd get a 1" 4-hole and open one and see what happens. If the traction is there I'd bet the closed spacer works better. That cam is a 12 second cam. It is just not the right 12 second cam for your setup at this time. The guy just forgot to tell you the rest of the stuff that you need to get into the 12's. Isky is big on the single pattern cams and the Buicks tend to like the dual pattern. Maybe if the heads were hogged out on the exhaust side it would be better. If I remember right the Nailheads like extra duration compared to the newer BBB but that is to make up for the lack of head flow. Extra compression never hurts. I'm sure the rockers would be worth something but they'd be worth more on the right cam and the cam is way cheaper to start with. When my '65 had the 401 they didn't know what a 60' time was. They were still handwriting the times on the slip. I'd say you 60' should be in the 1.8's a bit at least. The newer radial tires will do wonders. Try the easy stuff first along with tires and a higher stall if you have it.
I did a little playing with the carb spacers. not on the dyno though. even with a hoged out doc dual plane plenum, my nailhead for sure liked the 1/2 inch open better than the 4 hole. For me it seemed like the same lowend but for sure helped mid and top end. I dont have the same cam as Walt, but its worth a try. I might add, when I was testing intake manifolds on the flow bench my Doc dual plane I noticed that it was getting noisey so i slaped a 1 inch spacer on it and it quited down and gained 3 cfm through the head at .500 and .600 lift. I dont have to tell you where my 1 inch spacer is going this spring:Smarty: I bet that Cam Walt is running would love the doc dual plane and a spacer. Bob
Rhett, I have been Running a half inch open and it seemed to work better than the 4 hole half inch. On the bench the half inch gave 2 cfm, then I would put the one inch on and would get 3 or 4 cfm. I am going to try the 1 inch this late spring early summer, engine is apart againuzzled:. This is on the sq bore intake. The plenum is bigger on the q-jet, you will have to test it.
Good info, but with the carb pad of my DDP having so much surface area (as opposed to bringing the center divider to a knife edge on the top) I just wonder if an open spacer would cause too much turbulance allowing the unguided air to hit that flat surface - I'll try the 4 hole set up and see if I see any improvements, then chop it open and see if it changes anything....
I run a doc job with a 1/2 inch open spacer and it seemed to keep the low end and improved the mid and top. My 4 hole did not seem to have the same top end for some reason. I can only guess the 400 plus cubes wants all the air and fuel the heads and intake can give it. You will have to try it, Adding a carb to this mix might change things. I just know it loved the open spacer.:TU Rhett, I bought 2 four hole 1/2 inch spacers from summit for 12 dollars each. I then cut one open
I been reading these posts about the spacers with a lot of interest.... I have spacer/adapters on my intakes that still have the center divider in them.... and I have wondered,,, have you guys tried to test a spacer that is thicker but has the doc dual plane mod with the center divider still in .....??????? like the ones that I use but thicker......:Brow:
Spacers? what spacers? I don't run any spacers! My threads been hijacked!!ou: But, okay, I'll bite...anything for a tenth! Doc, I'm gonna throw this at you.... I'm thinking your Doc-modded intake is actually similar to adding an open spacer to HALF of the intake! To explain... cutting out the portion between the front/rear barrels out of the thin upper level of the intake probably doesn't do too much. But taking all that metal out between the carb and LOWER level of the intake adds a lot of volume to the plenum.... of those 4 cylinders. In effect, we may have 4 cylinders tuned for low/mid, and 4 cylinders tuned for mid/upper. ???? ....So I like your idea....it would keep the upper/lower levels separated for that 'dual tune'. BTW, I don't have the Doc modded intake on the blue car yet. It's on my milder red 66. I'll have to swap those intakes and see if there is a noticeable change. Cam advance....good idea Joe! But you know what's gonna happen.... I'll have the front of the engine apart to advance the cam, and I'll be looking at it.... and wonder why I don't just slide another cam in! I think that would be the best plan.
I totally take the blame for the hijack - even Bob (66GSConv) called me yesterday to talk about spacers and flow because we had to stop trampling the thread !!!! But it all leads back to the original topic in a real roundabout way.....better ET's, more MPH! Tom tried to get me to cut up my spread bore manifold just the way you described, but it was too late, I'd already taken both primary/secondary dividers out. He also taked about leaving the deep divider in, but kinda "knife edging" the bottom. Or maybe it was the shallow divider.... I cant remember. And sorry I couldnt call you back last night Doc...I actually to the DDP mod to all my base gaskets and plan to try that with my 4 hole gasket/spacer too. I flip you guys a picture when I'm done.. Now back to the original topic - Walt, your car runs awesome and I'm totally jealous of your 60 ft times! And since Mike posted the picture we can all see that the rest of the car looks as good as the LF headlight door! I hope we've got your wheels turning on some 2013 mods and subsequent videos! New tires, governor mods and cam timing and next thing you know the track will be making you weld a cage in it!!!
Dont know ,Walt,,, when I came up with the idea , all I was going for was to get more air to go thru the intake.... to eliminate it as a restrictor....I have actually thought about machining the whole top off of one and making a plate that would work with any carb, any carb... including the holley 4500... or using different plates........then while a man was in there he could smooth up all the passages real good.... box??? what box???? I did not even know there was a box.....:laugh::laugh:
Thank you very much for the nice ride Walt. I turn up the volume in my headphones to maximum watching this video! Maybe one day I can buy a helmet and drive my Riv to the strip and see what she can do. I love the clean look of the 66 and 67 Buick Skylarks and Gran Sports. Just one thing though, I can't figure out why Buick designed these cars with the small tail lights rather than the traditional long, narrow, and horizontal tail lights. Mind you, I am not complaining, but these Buicks look a little too similar to another General Motors A body car of those same years whose name I shall not mention in this Buick forum.
Thanks Craig. I've gotten addicted to the sound of a 5500 rpm Nailhead.... I think I'm going to make it my ring tone! I'm with you on the lame taillights. I love the full-width lights on the 65's. Wish they had kept that. I'm just busting on you guys about hijacks and carb spacers. I think it's funny how we (myself included) get carried away with our enthusiasm and can go off topic for pages and pages.....and pages!:grin: I honestly haven't grasped the concept why/how carb spacers work. It deserves it's own thread, it shouldn't be buried here in the Nailhead section where only about 5 people post! Doc, let's take it one step further:idea2:.... hog out the plenum of an intake, and make replaceable plenum inserts for different carbs and 4 hole/divided/open designs. We'll have Bob flow test them and Rhett can race test them!
Ditto, Walt; nice 'music'. Been a long time since mine saw anything north of 4000, and that was just to escape a drunk in an early Mustang that was weaving slowly left and right while slowing and then accelerating when he awoke and realized somebody (me) had passed him. We were the only cars on a fairly long stretch of five-ay-em freeway, and when he got in front of me, he would again gradually lose his own speed until he impeded my progress with his weaving. After four or five cycles, I had had enough and once he went 'right', I went to the floor. When the ST300 shifted at about 80mph indicated, I no longer shadowed a drifting Ford product; never got around to doing the math, though.....let's see, 2.78 rear, 1.82 low gear, converter slippage and speedometer accuracy uncertain.....I guess that's why I didn't complete the math. I, too, thought they missed the boat, and not just by eschewing the wall-to-wall lights. While the '66 taillamps have nice, sharp corners, the headlamp 'doors' (odd that they're called that, because they don't open) are rounded/radiused; the '67 is just the opposite. As I had designs on this car for a couple of years before I finally bought it, and it had a damaged front clip, I had seriously considered changing to a '67 clip so the front and rear treatments would 'match'. However, I eventually came to understand the concept of originality, and my '66 still looks like a '66 at both ends 34-1/2 years later. Gregg
Walt,the photo on right (fresh air) is good for at least 2-tenths and the photo on left is always good for 1-tenth.:grin:
Yup, already have a fresh air system thru the outside headlight openings. I like that setup on the red 66 tho.:TU: I know stickers 'make' it look faster, didn't realize it worked!p
