Nailheaders, I am new to your forum. I have recently purchased a 1966 Riviera with a 425 Super Wildcat dual quad. I would like all of you to share your experiences with this particular set up. Vulnerabilities, weaknesses, tricks, special tuning settings since the 1966 shop manual doesn't reference the settings for it. Also mine has been upgraded to hei with super coil. Yes, no points issues. I thank you in advance for assisting a new nailheader share the experience.
Welcome to the board!I've seen you engine's pic somewhere else,you've come to the right place,some of the guys here really know their stuff.The search feature on this site is very valuable.Good luck with the car.
Welcome to the board. What part of the country are you in and do you have any more pictures of the car? Rick
If any of you have a 1966 425 factory dual quad Please respond. I need some help validating the authenticity of the set up.
Where in Texas? I'm in Houston. '66 Rivi is my favorite car after the '65 Cat. I have a factory 2x4 in my cat. I'm sure someone with a '66 will chime in here. Rick
IMHO the nailhead engines are the best that was produced in thier time.... The cooling system is good as is.... the oiling system is good as is.... the block and heads are made of high nickel cast iron that doesnt wear much... the rods and crank are forged steel.... the factory cast pistons are good but also the weakest part of the engine... the other weak item is the key way in the harmonic balancer can crack in the thin part and ruin the crank if not caught quickly.... if the engine gets a high frequency viberation in it check the usual suspects [ water pump,fan clutch, ect. ] and the harmonic balancer key way.... prevention is the best cure... the crank bolt torques to a MINIMUM of 200 ft. lbs. that is not a typo... 200 min and 400 max.... the torque at 2800 rpm is the number on the air cleaner.... 445 for the 401 and 465 for the 425.... nailheads like big carbs.... they respond well to easy to do mods.... see my cheap tricks in the wrenching secrets section.... The term copperhead is a new one to me,,, cant elaborate on that... The 66 riv is one of the best,,,, worth keeping and will only be more valuable.... There is a lot of vintage and more modern speed equipment , like Toms roller rockers, cams, carbs like my favorite ,the 1050 holley 3 bbl, dress up stuff , headers ect. available for the car and the engine...... enjoy it...
Yes, I am familiar with it. Our club has been to it several times. You need to join the Houston Buick Club. www.houstonbuick.org There are several 2x4 cars in the group. I don't know the specific carb numbers, but your front carb should have no idle adjustment screws and no choke. I'd also look at the rear A/C mount. The correct ones are hard to find that provide clearance for the finned valve covers. If it looks like its been cut then it is not correct. Your engine code should be MZ to be correct for the 425 2x4 '66. Here is some specific engine ID information. LINK Also hit the link there that says "Click for more 425 identification" The engine coding basically goes as follows. For '64 "KT" is a 401, "KW" is a 425 single 4 bbl, "KX" is 425 2x4. The '65 is "LT" for 401, "LW" for 425 1x4, amd "LX" for the 425 2x4. See the pattern, first letter designates year and second designates displacement and carbs. For some reason '66 used MZ instead of MX for the 425 2x4. o No: Doc knows his stuff so check out his thread. Rick
Link to Docs cheap tricks. One of Doc's points reminded me...make sure your switch pitch is working properly. Most problems are at the carb linkage switch. Rick
I have gotten the engine codes and here ya go lx 332 5h924607 so, it looks to be a 65 2x4 complete set up in my 66 carbs front 3645sb cb5 back(primary)3925sa aa5 body tag says 06b second week of june. manifold 1370316b m 12 I have to figure out which way to go with the resto on this car. did the 65 have the switch pitch torq converter? for all intents of purpose this is a great start to a dual quad GS clone.
Didn't 64's have a SP400 too? I know it was a one year only design, but I'm pretty sure it was also a switch pitch.
My 64 Riv has a th 400 with no sw. pitch.... The 65-66 th 400 had sw. pitch. I think that I am remembering that Yaccy has a 64 riv that he swapped a sp into... it made a big difference,,, as I remember...
64's has a 3 speed ST400 trans, but no switch-pitch converter. They only had 2 forward positions on the shifter.... D and L. Your intake has the casting number of a '66. 64-65 intakes ended in 06, while the 66 ended in 16. Your front #3645 carb is for a 64, and the rear carb, #3925 is for a 65. Don't be concerned, other than the numbers, the carbs are pretty much the same. Only the 64 rear carb had different linkage than the other years. I wouldn't worry about the numbers thing, you have a cool car!:TU:
