View Full Version : dual quad 425

11-03-2004, 10:47 PM
i just pulled my 425 dual quad motor for a complete rebuild. my experience with the motor was that there was not enough cam in it. so far i've only been able to find a mild cam from compcams but no luck on roller rockers or roller lifters for the 425. all i am trying to do is get the motor to handle the quads without bogging. i'm not going to the races. any suggestions

11-04-2004, 07:46 AM
The problem with bog will not be in the fact that it is running a dual carb set up with the OE cam. The only reason for recaming it would be the same reasons you would use for any single carb system.

The likely places to look are in the accelerator pumps and linkages, or the vacuum pots that open the secondaries.

There currently are no roller rockers available for the the Nailhead. Dr. Frankenbuick did draw attention to a site where the fellow was developing some for it. I believe he was asking for preorders. I can't find the name or site right now.

Dr. Frankenbuick
11-04-2004, 08:20 PM
It was Tom Telesco that was working on the roller rockers. He is still working on the design with one of the Buick providers. There should be a very nice Nailhead roller rocker available shortly. That is all I will say for now.

11-05-2004, 09:21 AM

There are roller rockers available, at least in 2002 when I had mine installed. I have a 64 2x4 425 4-speed Wildcat coupe which I had a set of roller rockers installed on. I bought them from Earick Racing in Newark, Ohio, and I had them prep the heads and install the rockers for me. You might want to give them a call - 740-366-6672. I will tell you, though, they are not cheap, but if you really want a set, I believe they can help. As far as cams, I used a NH-400 cam from Postons with forged Ross 11.5:1 pistons. If you would like me to post a pic of the rockers on the motor, let me know and I will go get one.

Hope this helps and let us know what you find out,

Matt Menges

11-05-2004, 12:06 PM

Yes, I would like to see a picture of them! About how much was "not cheap" in 2004?

11-05-2004, 01:01 PM
Bob, what is your email address? I have a few digital pics I can email. Thanks,


By the way, Aaron Collins (bluewhale13) says hey, and his article should be ready this evening.

11-05-2004, 05:29 PM
You can email them to rcull graemlins/at_.gif buicks.net.

I look forward to reading Aarons article!

11-05-2004, 10:08 PM
tell me more about the 425 in your wildcat. did you use the stock intake and carbs? is the motor still well behaved with that cam? if you had to do it all again, would you change anything? thanks to everyone for all the input...this is a great site!!!!!

11-17-2004, 02:51 PM
My Dad had a Dual Quad back when it was new and he thought it was the worst Buick he ever had, and he traded every two years in the 60's and 70's, so he had some of the best Buick had to offer. He said that all it did was pour black smoke. Had a friend with the exact same car except with a single carb and he used to drive right past him. I am wondering if those carbs are to big for that engine, and that you can't get enough air into the engine to mix with all that fuel. One other thing to consider is that if the all those barrels open at once, where is the vacuum. Could be an issue. Wouldn't be with a blower on it.

Good Luck

11-17-2004, 05:58 PM
A buddy of mine is selling parts off a 65 wildcat convertible. if anyone has a need?




12-04-2004, 12:19 AM
Don't sell the dual-quad 425 short! I had a 64 Rivera with the factory set-up and had no problems with it except the secondary carb would sometimes stick open. A little mod on the linkage corrected that real quick. Other than keeping tires on it, it was very reliable in stock form and I beat many big-block Chevelles with it! Jim