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1966 Wildcat Sedan -- starting on the journey

General Information

Just bought this clean looking 1966 Wildcat. There is however a lot of work to be done, starting with the paint job -- a ugly pewter color over the original silver grey. First I'll need to treat rust spots to prevent further damages to the body (see below).

Next? Add a right windshield wiper (where do I get those?). The trunk door needs to be changed (rust on the lower panel, above the trim, following a parking accident by previous owner). The front bench is falling apart. Interior is original and otherwise well preserved but for missing parts. The AC has been removed, probably to gain some horsepower. Wheels are not original. The electrical system is messed up (either the radio or the road lights works--but not both at the same time :oops:). The air intake screw is too long and caused the hood to start rusting in the middle. Hood insulation must be added. All door joints replaced. Two doors won't open. Exhaust leaks. Etc.

Pretty much my alter ego -- looking good but missing a few bolts under the hood. I'd be done with that car when I retire, in 15 years, if ever. Ahahaha! 😅 But it is such a distinctive looking yet classy car.

Looking forward to connecting with other members in the Willamette Valley area in Oregon and to the broader community of Wildcat owners. In the meantime, I'd be thankful for any insights regarding my immediate tasks listed below. If you believe I should immediately focus on something else, please let me know.

First tasks -- damage control:
  1. Protect the body from rust where the paint has been chipped. Looking for the cheapest temporary stop-gap solution to buy me time to plan for permanent repair. What would you recommend?
  2. Get the engine and break inspected / fluids changed -- any recommendation for a knowledgeable shop in the Eugene, OR, area?
  3. Get a grip on routine maintenance (maintenance schedule, etc.), i.e. find an owner manual. Ebay?
  4. Add a right windshield wiper -- where do I get those?
Thank you in advance.



The no-crank-no-start continues to happen from time to time for no obvious reasons. But I now have a piece of electrical wire to start it from the power junction. Go figure...
For the weatherstrip of the trunk, I went with Steele. Don’t get Metro: not per original design. Be very careful there.

The Wildcat 1966 has a design defect: the channel is not tapered at the locking location to allow water to escape. If your rubber strip is not wide enough and well designed, water can accumulate in the channel and in time cause trunk door and strip channel to rust.

To prevent that from happening, the original weatherstrip was glued on bottom but also on the exterior wall of the channel. When you replace it, start first with glue on the bottom and place the strip as close as possible against exterior wall. Then the next day spray 3M weatherstrip glue between the strip and exterior wall to prevent water infiltration/accumulation in the channel.

The Steele weatherstrip is designed to expand laterally when compressed (initially the trunk door will be hard to close), thus filling the entire channel space. I would still add glue on the exterior side out of precaution.
For oil filter, I would go with Wix. They have an OEM model: 51049.

Website Link:

In the alternative, the best Wix racing filter might be the 51061R. The gasket diameter is larger (may experience some leaking) and it has no burst pressure rating (v. 260 PSI for the 51049). I am currently using a K&N Gold with an identical 3” gasket and experience no leaking.

The racing filter has a much higher flow 28 v. 11 GPM but lower filtration: 61 v. 21 micron rating. That’s the trade off: engine wear (less filtering) vs performance (more flow). I don’t believe this is an issue: tolerance of a 40 year old engine must be long past 21 micron. And a 61 nominal micron rating is still smaller/better than the original filters from 1966. Paradoxically, the 61051R is thus more likely to offer the same performance as an original 1966 filter in terms of flow rate and filtration for which the engine was originally designed.

A reduced flow rate / higher filtration could explain why some owners of 401 experience high engine temp. Synthetic oils have different viscosity and thermal qualities (they exchange more heat). With a modern, high filtration (low nominal micron rating) oil filter I would go with a synthetic oil like the Valvoline VR1. But thin synthetic oils tend to be hard on vintage gaskets. When I switched to Driven HR-5 10W-40 conventional hot rod oil, PSI went up a notch and so did engine temp — I bet GPM went down (I should have used Driven HR6 synthetic 10W-40 with the K&N filter). When I change the oil in 6 months I’ll switch to the Wix Racing 51061R oil filter and then re-assess.

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For all the fluids, including gas additive, I selected Driven.

For the oil: HR5 10W-40 Conventional Hot Rod. Link:
They also carry a synthetic version: the HR6 10W-40 — a better alternative to Valvoline’s VR1 if you decide to go the synthetic way. Note that Driven only sells (i.e. recommends) Wix racing oil filters. See above discussion re: oil filters.

Driven is a one-stop solution for all fluid needs. It is a time and thus money saver (even though their products are a bit pricier) — there are so many other things to deal with/worry about. Driven is convenient in addition to offering top products uniquely tailored to the hot rod / classic muscle car needs.

E.g. Defender+Booster fuel additive.
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Next is the issue of the radiator and shroud. I was about to snatch a reasonably priced radiator mounting panel on eBay.

The previous owner put in an undersized radiator, possibly from the like of O'Reilly. Inlet and outlet seem to be undersized -- 1 1/4 instead of 1 1/2 or 1" 3/4 in diameter. It is less than 1" 1/2 thick. No shroud -- a shroud drops the temp. by over 30 degrees. The combination of undersized radiator core and no shroud leads to spike in temperatures above 160 degrees -- up to 210 degrees when the sensor stop working.

For the radiator, I was told the original radiator had 4 rows. US Radiator seems the more knowledgeable supplier:
http://usradiator.com/buick-wildcat-1964-66-v8-401-425-radiator.html. They offer many model but the recommended models are either 005206AND (no factory air, cooler, 4 rows, 2" 5/8 core thickness) for the Standard Automotive ($816.88) or 005206ANDZ for high efficiency copper/brass construction ($981.25). With high efficient copper/brass, you can get the same thermal qualities with a 3 row model (005206ANHZ) as with the standard automotive model for about the same price ($825)--it will last longer. I think I will go with the 4 rows high efficiency model considering the small difference in price but large difference in cooling performance.

The other reputable radiator suppliers are reportedly Walker Radiator Works, Brassworks and AFCO -- but they do not have a Wildcat model on hand (AFCO does not even include the Wildcat on its list).

As for the fan shroud, I could not find anything, original, used or new. There is no direct reproduction available (e.g. Restoparts), so I am looking for the closest match I can use with mods.

Fan diameter is 20" (model with AC). The radiator core (17" x 28-3/8") is off-centered towards the passenger side by about 2.5" (the transmission cooler is on the driver side) so the shroud should be a bit longer on the passenger side. The core seats a little lower than the fan axle. I am looking for the closest match that I could use with a few mods, e.g. the Fan Shroud for the 1966-67 Chevelle/El Camino, Big Block might work (dimension?).

I'll post as a reply my final configuration and suppliers.

The air filter recommended by Wix for the Wildcat (No. 42084 - 2.36" height, 12" diameter) is only rated to 135 cfm, which is way too low to get the most of the 401 -- but it does fit in the air assembly:

From @1946holdenbody:
Is 135cfm a typo? To calculate air flow multiply cubic inch capacity of the engine x revs at peak power and divide by 3456.
350 x 5800 ÷ 3456 = 587cfm.
Adjust for volumetric efficiency (80% is a good rule of thumb number for a stock engine) and that will give you a fairly good cfm number to help choose your carburetor size. High performance heads and big cams will increase volumetric efficiency at higher rpm .
Hard to put in a filter higher than 2.4" without a dropped base. Clearance is non-existing, and in addition to limited CFM you don't want to suck the hot air that accumulates under the hood on back of the engine. You can't put an induction pan without cutting the hood and induction needs speed. So if you want to squeeze all horsepowers from the 401 for some urban burnouts, then you need another approach.

One solution is to go with a 14" K&N XStream Air Flow Assembly (66-3040) with a E-1650 3" filter and a 66-1401 air flow top -- stability of air flow coming direct from top instead of sides (less turbulence) is also apparently an important factor -- but instead of using the K&N base (1 1/4 drop) use a Speedmaster PCE101.1005 dropped base (1.5" drop) that gives you an additional 1/4" clearance.

In the alternative to the PCE dropped base, I would use an induction pan but turned towards the front to prevent the air cleaner from sucking the hot air from the back of the engine compartment. Something like: (1) Five Star Cowl Induction Cold Air System https://pitstopusa.com/i-5069534-fi...ass-for-a-14-element.html?ref=category:132346 (and add an insulation/weatherstrip band to get a seal with the hood) or (2) the Allstar Performance Lightweight Aluminum Air Pan https://pitstopusa.com/i-5066263-allstar-performance-lightweight-aluminum-air-pan.html (but I would basically cut the the flat panel and keep the round back).

And/or make a couple of holes in the hood and add hood vents: https://cheesebilt.com/products/universal-mount-vents

After I put the new radiator and get the transmission checked (and change the filter), I'll decide on final configuration for the air cleaner and reply with a photo and notes.

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Eugene, Oregon

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