[steve25]

Yup, just one of the other joys of a worn out vehicle.

[rolling money pits]

I’m not at all familiar with X bodys….how did the factory detent cable function, was it incorporated with the throttle cable bracket or run off the accelerator pedal?

If it’s on the bracket, is the untapped boss on the intake in the right location? If so, couldn’t one just drill and tap it? The bracket isn’t a high stress piece, so no need for half inch of threads.

[Verdoro 68]

It's an addition to the throttle cable bracket. I don't think it's unique to X-bodies. The cable runs down to the transmission vs. a TH400 which has an electric switch at the pedal. I thought about tapping the '68 intake, but the boss is in a slightly different location that doesn't line up with the bracket.

[Shiny]

Have you considered using a 1968 bracket and using an earlier A-body gas pedal-actuated kickdown? I suspect a custom bracket sounds easier, and you'd need another hole in the firewall, but maybe it would all be bolt-in?

[Verdoro 68]

Did TH350s use a gas pedal kickdown? The boss on the '68 intake isn't too far off - maybe 3/8" or so. Looking at it closer, it wouldn't be too hard to lengthen the bracket and tap a hole in the intake. The carb mounted bracket gets here in the next couple of days. I'll try that first and see how it looks.

[Shiny]

Your carb-mounted bracket will hopefully work and save you some grief!

Here's the TH350 kickdown arrangement on my 70 LeMans.

Two cables on gas pedal:



On the firewall side, throttle cable to carb and kickdown cable to transmission:

[Verdoro 68]

This explains why I haven't been able to find a throttle bracket that works for the earlier manifold. I wonder how F-bodies with a TH350 did it between '68 and '70? I did pick up a kickdown switch bracket for a '68 Firebird without researching. I assumed it mounted to the manifold for the cable, but I'm not sure. It won't work for my case anyway since the kickdown cable clip is square.



Converting to the pedal style looks like it would require a good bit of work. The accelerator cable and pedal are mounted completely different. The pedal itself also has the bracketry on the left side instead of the right. Here's the x-body side of things...

[b-man]

I had my TH350 built without a kick down cable. Mostly because I didn’t want to mess around with the Tri-Power linkage on my 421.

I still have the original 2-speed ST-300 console shifter, the linkage rod hooked up directly with no mods. However I can’t manually select low gear, which helps to me behave behind the wheel.

The transmission is only in low when I’m stopped in traffic. At full throttle it automatically shifts out of low at around 4600 which is fine. With the torque produced by the 421 I don’t really miss not having the kick down feature.

[Shiny]

Agreed, trying to replicate the 68 setup is not worth it.

Sounds like worst case is you fabricate a bracket for your bracket. You'll make it work!

As many of us discover, Pontiac made swapping intake manifolds and carbs easy. Then they made actually using them a major hassle.

[Holeshot71]

Originally Posted by Verdoro 68

It's an addition to the throttle cable bracket. I don't think it's unique to X-bodies. The cable runs down to the transmission vs. a TH400 which has an electric switch at the pedal. I thought about tapping the '68 intake, but the boss is in a slightly different location that doesn't line up with the bracket.

If this bracket gets you full throttle and proper kick down, drill/tap the hole and tweak the bracket so the holes line up and you’re done.

[rolling money pits]

Originally Posted by Holeshot71

If this bracket gets you full throttle and proper kick down, drill/tap the hole and tweak the bracket so the holes line up and you’re done.

Yeah…if that’s the intake you plan to use, slot the holes in the bracket so it moves towards the carb, then drill/tap boss for 1/4” bolt.

As said above, providing the bracket/cable/carb position arrangement gives you full throttle.

[Verdoro 68]

Looks like that's the best approach. The Q-Jet bracket I bought won't work at all since it hits the intake.

[Verdoro 68]

I spent more time strategizing and talking about it than actually doing it. Easy fix - drilled and tapped a new hole. Done in 20 minutes.



Things are starting to come back together. New motor mounts installed after a battle. I installed a new '74 GTO 4bbl fuel pump. Did a quick paint job on the frame after lots of lots of degreasing. Brackets and pulleys have been cleaned and painted. I bought the wrong throttle cable for a Firebird that won't fit through the firewall, so I'm trying to source one from a '74 GTO.

I know Sirrotica said to use a piece of metal to cover the crossover gap between the early intake and late heads. Can I used a Felpro 1233 with the square crossover inserts?

[Tim Corcoran]

Since your son has been daily driving the car it has proven reliability. The only thing I would consider is changing the timing chain and nothing else. I would not use 50wt oil in that car. Not sure why people think thicker oil is better for a factory stock car designed for 30wt oil. I would put 10-30 oil in it.

[73_Lemans_350]

Originally Posted by Verdoro 68

I know Sirrotica said to use a piece of metal to cover the crossover gap between the early intake and late heads. Can I used a Felpro 1233 with the square crossover inserts?

When I went from the 2 barrel to the Quadrajet, I blocked the crossover with the piece that came with the gasket (with no hole in it at all), but I am not using a choke. It seems to start and run cold as well as it did with the 2 barrel and a choke.

[Verdoro 68]

Originally Posted by Tim Corcoran

Since your son has been daily driving the car it has proven reliability. The only thing I would consider is changing the timing chain and nothing else. I would not use 50wt oil in that car. Not sure why people think thicker oil is better for a factory stock car designed for 30wt oil. I would put 10-30 oil in it.

I put a new stock timing chain on and buttoned it back up. I ran 50wt when I didn't know what kind of oil pressure it was making. I may bump that down now that we know things are good.

We bolted up the front accessories, cleaned and repainted all the hardware and bracketry and installed the intake manifold. I mnade a list of stuff we want to get done before the road trip. Waiting on the '74 GTO throttle cable and a bunch of bits and pieces from Ames to put the carb on. I found a couple more things as I've been going over the car. When I dropped the starter to put the motor mounts in I found that the battery cable was really loose at the solenoid. The suspension had an annoying creak on the driver's side so we decided to dig in. Turns out the spring wasn't in the pocket and knocking really bad against the frame. I disassembled the suspension and found that the sway bar end link was missing a bushing. Both easy fixes. I'm glad I noticed the battery cable in particular - that could have bit us later.

[Verdoro 68]

Mocked up the carb yesterday. I discovered that the bosses for the throttle bracket are about 1/2 more outboard on a '74. Back to the drawing board for the linkage. I"m thinking about making a bracket that will offset the stock setup to where it needs to be. I also need a different throttle lever with a provision for the kickdown and a longer kickdown cable

[PontiacHO]

I used an adjustable Kickdown cable for my 68 Firebird. Although I still don’t have passing gear (valvebody issues) it fit well after the length was adjusted to fit. I had to get an accelerator cable pin to adapted to fit my Quadrajet (1977) to get the throttle cable to fit. Had to drill another hole in the linkage.

[Verdoro 68]

It turns out you can fire up an engine if the Q-Jet doesn't have any primary jets or rods and the needle isn't in the seat...it just doesn't like it. Stupidly, I didn't think to open up the carb and make sure it was all in order. In my mind I just took it off my '68 and packed it away. I clearly pillaged it for parts at some point. Didn't take me long to figure out something was up when fuel was spewing everywhere.

Fortunately I had a rebuild kit on hand and extra rods and jets so it didn't take long to get things fixed up. I put a 42B/73 combo in it for starters. Once I put all the pieces back in the carb it fired right up LOL. Got it timed in and idling smoothly no problem. I picked up an adjustable kickdown cable I'll swap that in later this week and figure out the whole linkage situation when the longer accelerator cable gets here.

It needs an oil change now after the carb debacle, but that's no big deal. I think we're in the home stretch. Once we get the seats back, we'll take it for a few long cruises to make sure it's good to go.

[steve25]

You’re now part of an elite few who did not have everything burn up in front of them!!

Lucy you are , as Yoda would say.