How to Stuff A Tbird '66 428/C6 Combo Into A '59 TBird Engine Bay!
Terry Shannon ~ BEVS BIRD

The following is a step by step procedure, on how to replace a 352ci engine in a 1959 Squarebird with a Flairbird 1966 428/C6 combination. This information was presented for those who will need this information in the future. Thanks, Terry.

The good stuff ... WHAT A GREAT SWAP....

Beautiful upgrade on torque, and that C6, what a sweet upgrade from the COM.

Here is the short story.... or maybe not... No engine swap is easy, but this one was very straight forward.

Engine and transmission are from a 1966 Tbird. Rebuilt 428 by local Shop that is an FE expert shop, and rebuilt C6. Sat in the '66 since 2011, never fired up. Both the block and head casting support 1966-1970 428 castings.

Block Casting # C6ME { indicates '66-'70 428 block} located on right front lower block. Or could be possible C8ME {'68-'70 428 block}.

Head casting C8AE or _8AE hard to read.. Indicates 428 heads..

Towed car home and Fired er up.... Orig Ford carb {4v}, it had been rebuilt, but ran horrible. I installed a Edelbrock 1411.. 750 cfm, electric choke.. good right out of the box, 16 inches Vac.

I had the overhaul billing, but no cam specs, sounds non stock, and lower vac may support that.

60 psi cold oil pressure and 35 hot idle... no leaks.... good news on an FE!! Transmission filled and ran to check levels and leaks... good.

So, I first pulled the 352, and I left the transmission in as I worked on the floor, no problem, then pulled it. I had to drop drag link to get forward clearance to pull trans.... no problem...

I pulled the 428 and C6 same way. Easy job on the '66.

I pulled the 428 pan and checked Mains, good and end play .007" good.

I looked at the cam from the bottom, looks good, pulled plugs to rotate engine. I could see new pistons, which was supported by the overhaul paperwork. Everything new... OH YEAH!!

I pulled the rocker cover. All gear looks good. Heads were rebuilt with hardened inserts.

Reused the 428 water pump {shorter shaft} and 428 pulleys, 352 a/c fan and 428 spacer... This engine was balanced, but I didn't want to fool with unbalanced cam/shaft pulley etc..

Reused the '59 generator etc... Will possible upgrade to alternator later, but all is working good.

Reused the '59 speedometer gear and cable.. Reads very close..

Everything bolted on as if it was the 352... good news.

The 428 water pump had minimum casting clearance on the inlet leg between leg and generator belt, but no contact after 100 miles.. The 352 pump had a casting indent for more clearance, plus longer shaft.

Transmission and C/Member. 1966 T/Bird C6 had the same dimensions as the COM. It turned out to be an easy swap.

(Added Note): The 428 block had 2 sets of MOTOR MOUNT holes, I used the REAR SET. I had good radiator/fan clearance so the whole set up fit in nicely. I have good clearance on the expansion tank, and 1/2" between fan clutch and radiator center support strut. Now on the highway, there is no roaring fan. The fan picks up the idle speed, so no overheating at this point... I have used this set up on previous hot rods with good success. So I don't expect any trouble..

Reused the 1959 c/member... the main body support had an extra hole rearward of the COM mount position {standard transmission position?} but the floor was not drilled... The C6 mount position fit exactly this extra hole location... So I drilled thru the floor and moved the Factory double mount studs rearward one hole set... PERFECT FIT for the cross member and the C6 mount.

This also meant, near stock location of transmission and 4 degrees down at transmission tail shaft... Same as I measured on the '59.

I modified the '66 transmission mount slightly by trimming rubber, and using '66 transmission mount bracket. MUCH narrower then the '59. Fit good and same set up now as the '66.

The '66 drive shaft was SAME LENGTH as the '59.... I had to use a conversion U joint on the '59 shaft to install C6 yoke and it bolted right in.. Good spline depth, and seal clearance in transmission. Conversion U joint, Spicer TK 40720 .. [1310 x 1330}. 1.062 caps, 4 round Outside snap rings, 3 5/8 inches by 3 1/4 inches.

So if you wanted to put a C6 behind the 352 in a Squarebird, I think it looks like an easy swap.

Same shifter pattern as the COM, and used the '66 shifter linkage.... PERFECT.. Full range L to P and free pin at each detente.

I used a Lokar cable Kickdown and throttle kit and eliminated that Ford kickdown rod... works great.

Even the windshield wipers work with the standard 428 fuel pump {no Vac assist on pump}.

NO over heat with stock '59 Radiator. Weather is still cool here yet... I hate that fan noise, so will go to electric set up. (Added Note): To eliminate that awful fan roar, I decided to go with a clutch fan hub and 7 bladed fan. The original generator would be marginal at best to handle the extra load of an electric fan. I will upgrade to an Alternator at a later date. The clutch fan was IN STOCK at the local parts place, wow! I ordered a 1966 Thunderbird 428 clutch fan hub. [HAYDEN 2710 FAN CLUTCH] and under $50.. I sourced the 7 bladed fan at the wrecking yard for $10 bucks PLUS TAX PLEASE! the guy said. I have no idea what it came off. It was the first one I picked up and measured 18 Inches in diameter, and had the big center opening for the fan clutch. Note: Summit Racing has the Hayden 2710 Fan Clutch listed for the 1966 Ford Thunderbird 428ci at $30.99. Other auto parts stores also have it listed for about the same price.

Hayden 2710 Fan Clutch

The Emergency brake cable casing mount bracket on the c/member, was now 2 inches farther back. So I dissembled the casing from the upper mount, pulled the casing down, attched to the c/member, reworked and repositioned the forward casing bracket downward, and it works great. I had to re-thread the Emergency brake adjuster rod, about 1 1/2 inches, for the same reason {cross member 2 inches farther back}.

428 exhaust manifolds will fit, but have the tapered donuts, so used the 352 manifolds [ flat gaskets] to match the exhaust system.

The manifold ports and dimensions are almost exactly the same, which I found hard to believe.

What a treat to park without the puddle underneath, and VERY responsive performance!

I probably missed tons of good info, but a very good upgrade on the Ole Bird! Should you have any questions feel free to email or send me a Private Message.

Created: 29 June, 2019

Last Modified: 6 July, 2019

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