Streetmaster in a Thunderbird

[Riderjeff]

My (limited) understanding is that classic Thunderbirds with FE engines had a flat non-angled carburetor mounting pad. That may be a generalization, but my '65 came with an angled spacer/heater that "corrected" the mounting pad from a generic FE intake to allow for the lower engine position.

I've got a C4SE iron intake for reference, it measures 9/16" height from the forward carb holes to the valve cover rail, the rear measures 1 1/16" from the rear carb holes: 1/2" different front to rear.  With the C5 spacer sitting on the carb pad, the height is 1 13/16" at the front holes, 1 15/16" at the rear: 1/8" different front to rear.

My intent is to run a Streetmaster on my new engine.  the Streetmaster measures 1 9/16" at the front holes, 1 15/16" at the rear holes: 3/8" different front to rear.

My question is this: while it's in the shop, do you think it would be worth the effort to machine a 1/4" "wedge" off the carb pad on the Streetmaster to get the same mounting attitude as the stock setup?  That should leave me with a 1/8" difference.  The good news here is it appears the Streetmaster will fit well under the stock hood/air cleaner/etc.

Worth the effort?  Don't bother?  The carb isn't that picky or gotta fix this up front?  Your thoughts would be appreciated.

Thanks, Jeff

[chris401]

The only Thunderbird specific intake I am aware of is the factory aluminum 3 Deuce. The single 4 barrels had a wedge shaped spacer on top of a passenger car intake.

[Joe-JDC]

The Streetmaster should fit as is with a 1/4" spacer under the carb.  I would angle mill a spacer before modifying the intake manifold.  Joe-JDC

[shady]

I would just use your spacer and put some caps on the heater hose nipples and not run the coolant through it.

[frnkeore]

The reason that carb pad are angled is, specifically, to have the carb approx level, when installed in the car. The c/l of the crank, is higher than the low Hypoid type pinions. The engineers try to align the crank at a angle that lines up with the pinion. The pinion is also angled up to have a straight drive line.

Carbs are designed to allow some off levelness approx 3 to maybe as much as 5 deg. So, the actual way to know what you need, is to install the manifold and put a level on the pad.

[cammerfe]

If you mill the carb pad, the mounting studs will not be at 90 degrees to the surface. You'll either need to plug the holes and re-drill at the correct angle or modify the holes in the carb base.

KS

[TomP]

The small difference of angle isn't an issue for that but ideal would be the studs are reangled or the carb has wedge shaped washers. This is not exactly for the space shuttle and the studs being at an angle to the carb is "good enough" to work. Just watch for clearance at the back of the air cleaner.

[My427stang]

If you don’t have air filter clearance issues, I would run it with forward slope.  When you are on the throttle it doesn’t hurt to have a little extra angle to keep the rear jets covered

[MeanGene]

A couple years ago a guy with a 65 Bird drove by and saw my Q-code 66 in the driveway and stopped, and he had a Streetmaster on it with a thin aftermarket air cleaner, and it fit fine

[frnkeore]

For something like that, you should at least have a K&N type top.

[Riderjeff]

Thanks for the input, everyone.
I'm thinking that for now I'll not sweat it and just wait until it's installed to see what I'm up against.  If there's still clearance, I could machine down one of those phenolic spacers into a narrow wedge to correct the angle and get a little insulation.  Kinda doubt that there will be enough clearance for the factory spacer, but that way it'll be easy to check.

[chris401]

Thanks for the input, everyone.
I'm thinking that for now I'll not sweat it and just wait until it's installed to see what I'm up against.  If there's still clearance, I could machine down one of those phenolic spacers into a narrow wedge to correct the angle and get a little insulation.  Kinda doubt that there will be enough clearance for the factory spacer, but that way it'll be easy to check.

I have one of those phenolic spacers from a Q Code. P.M. me if you can use it, doubt I ever will.

[Falcon67]

Do not IMHO mill the intake.  That ruins it for any potential future resale.  Get everything in the car then lay a angle measure on the intake flange and decide from there.  Usually there is a 2~4 degree down angle in most cars.  Couple fo degrees won't make much difference.

>The pinion is also angled up to have a straight drive line.

Straight as is the tail of the trans is in line with the pinion in the horizontal plane.  They are offset in the vertical so that each u-joint is at an angle to the driveshaft.  Otherwise, the u-joints won't spin and then will self destruct. 

[Riderjeff]

I have one of those phenolic spacers from a Q Code. P.M. me if you can use it, doubt I ever will.

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