[eodcoduto]

This spot looks like it will get the most traction so here it goes. I recovered my '74 T/A after 23 years of sitting in a barn, I went in the Marines in 1998 and retired last year, and its been robbed of a ton of parts so I put it up for sale. But I got more calls from guys with parts to put it back together than I did anyone wanting to buy it so its time to get it back on the road. My daily driver is a 2014 VW Passat TDI and it is getting sold when it hits 118,000 miles as the dieselgate warranty is up at 120, its at 101,000 now. Then the T/A will be my commuter car. Its an 18 mile trip each way, 4 stop signs and 55-65mph zones the whole way.

Here is my plan and sanity check it as needed. This is an original 455 A/C car with black deluxe interior. The engine is long gone and I have a 1973 Y4 400 with 4x-4 heads and the original th400 to go in it. The plan is a 350hp range goal, keeping the 3.08 rear and probably adding an aftermarket fuel injection system. The goal is 15mpg on 91 and dead nuts reliability. I need quite a few body parts and the paint will be the last thing that gets addressed.

Unless a 455 falls in my lap this is the engine I have to work with. I have a thread for parts wanted in the 74-76 section and I have about 15 months to get this on the road.

Fire away.

[ta man]

Up your goal to 18 to 20 mpg on 87 octane.

[eodcoduto]

Challenge accepted. It still needs to be capable of a 13.04 quarter mile though.

[Brentco]

First, you made the right choice keeping and restoring the TA! Get that thing back on the road! Do you have another car to drive if the Pontiac is out of service? Even if you do everything possible to meet your goal of dead nuts reliability, I guarantee there will be times when the TA is down.

Are you doing a complete rebuild of the 400? If so, just drop in a stroker kit to get you your 455 (or larger) cubes. The 4x heads should put you at a good compression ratio with the longer stroke (but be sure to run the numbers before hand). You’re lucky to be in the South. You’re (relatively) close to a lot of the major players — Butler, all the Comp Cams brands, Edelbrock, Firebird Central, etc.

[25stevem]

My info shows that 400 to be 2 bbl motor out of a B body car and as such the TB400 will be a long tail shaft model so you will need to have your driveshaft shortened.

Those heads are 98 CCs so you will need to mill them at least .030” and run 2 valve notch pistons and zero deck the motor to get to a decent 9 to 1 compression.

[eodcoduto]

I have the original Th400 in my Trans Am, and I will either mill the heads or find a better set with smaller chambers. I had #62’s on my ‘69 400, with a set of those and the stock 400 pistons I might be able to get close.

[kingbuzzo]

What a great project.

I'm looking for another engine for mine so I'll be watching your progress on the build.

Good Luck and thank you for your service.

[JLMounce]

I wouldn’t try to reinvent the wheel with the engine. Rebuild if necessary, keep it close to stick with some minor improvements and an eye toward serviceability and reliability.

Given this will be a daily, I would be looking to make sure drive comfort is a priority. Comfortable and functional interior, properly functioning gauge package, sorted steering and brakes.

Good luck with the project!

[Formulabruce]

Try running the engine as is first Add a HEI for reliability.
Milling the block and heads and all the higher compression talk will cost you a LOT of money, and a LOT of time for
a commuter car.
That 2bbl motor will get you 18 with an auto and 3.08 if not stomped on.

[dataway]

If it's truly going to be a DRIVER ... make it a driver. Go real easy on the performance options. If you want the car to really end up being your friend, make it RELIABLE first, economical second, performance third.

Others may have had different experiences but ... on a limited budget ... performance and street reliability don't mix. Not saying it can't be done, many people have, but it's not cheap. Reliability AND performance requires the very best machine work, assembly, parts and huge amount of thought put into how you get your performance. And only the most experienced builders can pull it off in one try.

What a great car to turn into a 17-18 mpg, reliable head turner. Just remember how much 100 extra HP can cost you in money and frustration.

To me .. Fast Car or Daily Driver ... and never the twain shall meet

[1965gp]

I agree with what others have said. 13.0 is fast for a mild second gen. Damn fast in my opinion. Fast car or daily- you will be much happier and have better results choosing one to focus on.

Is there a budget for this project and what is included in that budget? For example do you want new shiny paint or as is with everything operational?

This would be my plan for that car:

-high quality wiring harness for the entire car, I would probably go stock but some may choose something like Painless.
- replace rear seal in transmission, add slightly higher than stock converter
-add HEI to the 400 and detail the motor/hope it runs
-long tube headers/exhaust of your choice
-cold case radiator, stock clutch fan and shroud
-vintage air/heat
-add subframe connectors
-replace front suspension bushings/ add tubular upper/lower control arms if $$ allows
-keep factory brakes for now
-lots of dynamat or similar sound deadening (but remember this add weight)
-if it’s a daily I might consider aftermarket seats, or at least put new foam and covers on existing seats.
-aftermarket gauges/ I am a huge fan of www.speedhut.com and have these in my 72 bird
-17/18” wheels and modern tires
-hid/led headlights and taillights

I think you will be surprised how well a 400 with long tubes and a loose converter can move that car. If you convert to a 4bbl I would suggest a high quality quadrajet for economy, however my quick fuel carbs have been amazingly reliable so I might look at their entry level carbs (600 cfm- they come jetted a little heavy). My 69 bird has a quick fuel on it and it can sit for weeks and fire up on the first shot.

The seats, subframe connectors and suspension are going to make it so much more enjoyable to drive. You may look into aftermarket seat belts as well.


Keep us posted- seems like a very cool project!

[eodcoduto]

I agree with you all, the engine needs to be close to stock and there will be modern sound deadening material used. Wheels will be 17 or 18” and I can’t decide on ralley II’s or Honeycomb yet. The heads will get shaved and rebuild unless another set with bigger valves pops up cheap. I’d rather spend the money on a real 455 than making a stroker if I go that route, only for historical purposes and not performance.

[ta man]

I like the plan of rebuilding the heads and milling them to increase compression. For the cost involved well worth the benefits.

[android 211]

IMHO: Quadrajet, '72 cast intake, your 4X heads rebuilt as is, your 400 block zero decked with cast flat top pistons. Summit 2801 cam. RA exhaust manifolds with a 2 1/2" system. HEI recurved, windage tray, baffled 73 up oil pan, no taller than 3.08 rear gears, 225/70R15 tires. I had an early TA with headers, they scraped the ground too many times and I went back to RA manifolds. This engine will get high teens mpg on 87 and still have decent power. Stick with stock converter for efficiency. My '72 455HO got 16-17 on long trips, it had 2.73s in back.

[OCMDGTO]

Really cool project! I think you're going to need more than 350hp to go 13.0. I wonder if out of the box aluminum heads would help with efficiency? I would have a back up vehicle and with your short commute you could go wilder. Thanks for your service and keep updating.

[track73]

I believe those 73 400 pistons are chamfered and will get you around 9:1 compression with number 62 heads. My advice is to re ring the pistons, get a good valve job and put in hardened seats on the heads. Then get an RV type cam. That should get you there. A good q-jet will be more reliable than an after market FI. Good luck.

[Formulabruce]

Originally Posted by ta man

I like the plan of rebuilding the heads and milling them to increase compression. For the cost involved well worth the benefits.

Just WHO spends $1500 to Correctly update and rebuild 4X-4 heads?

[Formulabruce]

Originally Posted by eodcoduto

I agree with you all, the engine needs to be close to stock and there will be modern sound deadening material used. Wheels will be 17 or 18” and I can’t decide on ralley II’s or Honeycomb yet. The heads will get shaved and rebuild unless another set with bigger valves pops up cheap. I’d rather spend the money on a real 455 than making a stroker if I go that route, only for historical purposes and not performance.

Based on what ya like here, you have an unlimited budget, dont care about fuel economy, and want it all.... You can have it, even WITHOUT Zero decking, and milling heads, it just costs lots of money. With the backlog at most machine shops and the high cost, Im betting your driver, will be that, a good driver.
99% of folks in this "street" section either drag their cars or do NOT Daily them.
Easy to get suckered into making a 1 off engine you cant swap stuff on without having it "milled to match".
>> A STOCK 1970 L-65 400 2bbl makes 400 ft-lbs of TORQUE
at ONLY 2400 rpm ( long before any Dyno place even starts graphing power)
With exhaust "LOGS".
SO Your motor will sit you back in your seat and have TORQUE in your driving RPM range...
.. rant off..

[lugnutx2]

It being an original 455 car, that's what I'd put back in.

[ta man]

Originally Posted by Formulabruce

Just WHO spends $1500 to Correctly update and rebuild 4X-4 heads?

If they are in good shape it won't even be a third of that cost..