About to rebuild a 400, looking for advice, all opinions welcome

OK, I am taking a 67 GS400 engine to be rebuilt next week that I will put in my 67 SportWagon as I am making it a GS400 clone. I am putting a GS400 hood on the car and when you raise that hood you will see the GS400 set up, Star Wars AC and all. This wagon is intended to be my weekly driver, not daily but a lot more use than my other car toys. My wife and I plan to drive it from Texas to Wisconsin for the BCA National Meet this coming July and enjoy not only the car but sights and scenery on the way.

I had one GS400 engine rebuilt for my hardtop two years ago by a local machine shop and other than new pistons and rings since we bored the engine 0.30 over, the rest of the engine used the original parts which were in good shape. I want the engine in the wagon to be the best value I can get for the dollars spent. I have been monitoring discussions on this site about cams, pistons, etc. trying to understand what I could do that would boost horsepower maybe 10-20% but this will not be a car going to the strip on weekends or ever. I just want a super running car with significant power when I need it. The 340 in the car is tired and not numbers matching but it moves the car along nicely. the car is loaded with options including factory air, power steering and power brakes, so we lose some power pushing those options.

I don't know yet what shape the internals of the engine to be rebuildt are in yet but heads have been removed, pulleys, water pump, intake, are off so it will be further dismantled in about a week and measurements taken. I am anticipating a .30 overbore from wear and tear so new pistons/rings are in order along with all the bearings etc. I am thinking I will spring for new valves, springs, etc. so the valve train is new. I am assuming the heads are OK but will be checked for cracks and then if good prepared for the new valve train perhaps including hardened seats since I will drive this car on a weekly basis.

From reading the recent posts on cams it appears the TA 112 cam would give an additional 20 hp and the 212 gives 40 hp. All other parts IE: carb, distributor, water pump will be OEM although the distributor may be upgraded with electronics. I have the correct carb for the 400/auto trans that has been completely rebuilt so we will go with that to start.

So, I am wide open to receive advice as if this engine was yours and you know I am looking for a really nice driver with a little more HP than stock. I will evaluate all recommendations and try to come together with a package that I tell the engine rebuilder I want but I need to be ready to do this by the end of next week before the engine goes off to the machine shop,

Thanks in advance for thoughts and recommendations. I intend to start a post on the engine swap and conversion to a SportWagon GS400 clone, which was not an option in 1967. This should be a fun project with a great car to with.

 

On your last 400 rebuild, what brand or company did the pistons come from?

 

I cannot tell you since I gave the machine shop the green light to use their suppliers. It might be listed on the invoice but not sure I can lay my hands on it quickly. I was not really into that engine like I am going to be on this rebuild.

 

The reason I'm asking is the only Buick 400 piston that I know of is the Egge L2273 and the TA 1603 which appears to be the Egge piston also.
The problem with that piston is it has a compression height (Pin Height) of 1.953" which puts the piston about .060" from the top at TDC.
It is also just a cast piston.

Ideal case for maximum quench is to have the piston at zero deck height to minimize detonation and allow the most efficient fuel burn.

The second option is to have Autotec make a 4032 alloy forged piston with a CH near 2.00" so the piston will be at zero deck after a clean-up cut to the block deck.
The piston will come with the correct volume in the dish for the compression ratio needed to go along with your cam choice.
The pistons will be set up for the modern thinner rings for less piston drag.
This is what their 455 piston looks like.

http://www.buyracingparts.com/blog/wp-content/uploads/2011/10/AT455BT.jpg

Just something to consider.

 

It's not the original engine, so numbers-matching isn't an issue.

You're crazy to rebuild a 400 when a 455 gives you more torque and is easier to source parts for.

 

If the OP already has the 400, I suppose that is a cost consideration.

Otherwise, ditto what you said. If you aren't original, why spend the exact same amount of money on a less desirable motor? Gas mileage won't be that much different and if it was an issue, you'd be better off with a solid 350 SBB.

A SBB 350 will be a near drop in. Add headers, a small cam, turbo 350, a matching torque converter and you will have a great little combo that handles well and be more fun than what you have now.

Your motor and your money though. Good luck with it.

 

67/8/9 heads were prone to crack external between the valve spring area. If using them, they need to be checked out for cracks. Tale tail signs are washed clean areas between the valve springs with the rest of the inside gummed up, and condensation in the valve cover.

 

There are quite a few casting numbers for 67-69 400-430 heads and not all are as prone to cracking as the rest. I'd bet Jim W or Greg G could shed some light on that subject. Here is a list of head casting numbers by year that I found. * denotes Big Port and 69cc chambers.

1231109 68-69 430
1231786 69 400/430
1231786 70 455
1237661 71 455
1238148 70-72? 455
1238529 70-76 455
1238530 72 455 Stage 1
1245713 69 400/430
1240144 70-71 455
1240145 71 455
1240146 71 455
1240149 70-71 455
1240150 70 455
1241860 73-74 455
1242001 73-74 455
1242445 70-72 455
1242449 72 455
1246322 75-76 455
1246332 75-76 455
1248922 72-76 455
1250489 75 455
1372963* 67 430
1372985* 67 430
1372986* 67 430
1377979 67 400
1377980* 67 400
1382091 68 400,430
1382720 67 400
1382983* 67-68 430
1382985* 68 430
1382986 68 430
1384720* 68 400,430
1385649 68 400/430

 

Great comments guys. As to the 400 vs 455 it probably sounds corny but my intent was to upgrade the SportWagon with all 1967 parts and therefore the concept of the 67 400 engine. I already have then engine dismantled ready to go to the machine shop for magnafluxing and wear and tear checking. If for some reason it has problems, I have another 67 400 I could send them. Now if for some reason both 400's are not rebuildable then I will re-think the engine choice and perhaps consider a 455.

The numbers on the heads on the engine I intend to rebuild are 1377979 H 30 which show up on the extensive list shown. We will check them carefully for cracking once they are off the block and at the machine shop.

Sounds like piston and cam choice is something to focus on now so there will not be a delay once we get the block done and know the overbore if any.

Any comments on the cam choice? I intend to talk with TA next week for their recommendation for an excellent driver without ever going to the track. Seems like the 112 or at most the 212 makes sense.

Thanks again for the comments and keep them coming when you have a few minutes on the Forum.

 

Love that Sporty Chuck! Here's a car with similar intentions as yours..........................http://www.cars-on-line.com/87219.html

Of course it looks much better in black.

 

Nick, I too saw the silver 67 SportWagon when it was first listed and corresponded with the seller with a question. His response could not answer my question since it sounded as if he was a car broker or had bought the car as is and then was trying to sell it. It is extremely nice but goes beyond my intention of keeping mine as stock/OEM as possible.

I do love the conversion to bucket seats and console which I have considered but it is quite an investment to do it correctly. Also my front bench seat was recovered just before I bought the car 3 years ago. The original embossed trim that is also on the door panels was cut out of the original seat cover and sewn into the new material so it looks very nice and original. Sort of a unique detail for the SportWagon 400 loaded car. I would loose that detail if I went to buckets. The detail is also on the second and third seats. I want to get the rebuilt GS400 engine in the car and running great and then weigh the option to convert to buckets and console.

 

The 112 offers more low end torque than the 212 but it also requires 1/2 point less compression ratio than the 212 because of the earlier closing intake valve.
What octane fuel do you want to run?

 

I'll be following this thread as I've been looking at 400 piston options with little luck.

 

You should also be able to bore that 400 out to 430 CID. Cheap easy hp. I'm running the TA 212 cam and very happy with it. I just had to open up the idle tubes to eliminate the off idle stumble. Lots of power now...

 

I would put the higher octane gas in the car. Won't be driving it all that much and what ever works best is what I will use. I like the idea of the low end torque of the 112. Once in a great while I may pull my 4 x 8 aluminum trailer here and there and could use the low end torque.

 

I am getting good advice offline from the Forum so I will keep the thread active when I make the final decisions in the next week or so.

 

I recommend using the Crower 52239 cam.
It is a good low end torque cam with .050" intake duration specs just 2 degrees more than the TA 112 for a little additional horsepower.
The main advantage is that has 16 degrees more advertised duration which will allow a higher static compression ratio to benefit torque and fuel economy.
The longer opening and closing ramps are also easier on the valve train and valve seats in the head.

TA 112:.......... 210*/215* @ .050", 260*/262*. advertised, .455"/.468 (1.55 ratio valve lift), LSA 112*
Crower 52239: 212*/216* @ .050", 276*/281*. advertised, .460"/.471 (1.55 ratio valve lift), LSA 112*

I would run a 9.5 to 9.7 compression ratio.
For maximum quench velocity at low cruising rpm, the piston should have a "D" dish with the piston set at Zero Deck height @ TDC.
No piston valve pockets are needed with a stock valve size 400 head.

If you can get away with just a .020" over bore the piston would be 4.060" which gives you a large variety SBC piston rings to choose from.

Depending on the final combustion chamber volume (assuming 69 cc) the piston dish will need about 16 to 18 ccs
The piston pin compression height will be near 2.00" to get zero deck.

 

If the plans include the AutoTec pistons anyway, then a bit of extra stroke will help get your goals of more power than a stock '67 400 had back in the day.

With a bore of 4.060" and a .160" extra stroke you can gain an extra 19.97, basically 20 more cubes so a 420 cid. You can use aftermarket Ford 5.4L rods to do this, they're 6.658" long so you can get your compression distance down .058"(factory rod is 6.600") + half of the extra stroke .08", so .058" + .080" = .138" less compression distance for a piston that would be 1.862 if before stroking 2" is what you needed. The pistons would need to be ordered with .866" wristpins as well for the rods. The big end width will need to be machined down from .940" to .928" around .012" removed from thickness to make them fit. Should be no problem to use the 5.4L bearings and with the .160" extra stroke you would need the .25mm under bearings to get the full .160" extra staring with an unground crank with the nominal 2.250" rod journal size.

Something like these;

http://www.ebay.com/itm/CXRacing-H-...ash=item2578e03cab:g:cDEAAMXQVERS4Kg7&vxp=mtr

These Ford factory rods would work at your power level too and a bit more budget friendly;

http://www.ebay.com/itm/2003-LIGHTN...ash=item2826afffc6:g:KhUAAOSwnHZYQPLg&vxp=mtr


Or with the bore at 4.125" where there are plenty of good rings as well, with the extra stroke with the above rods you would have a 433 cid. Dealers choice. GL




Derek

 

If those factory 5.4 rods are PM, I would strongly caution people about using them in a performance application.
Unlike reglar ol forged rods, PM's let go without warning rather than bend or distort.
They also don't show much indicating the end is near during inspection.

 

OK, I am learning a bunch with the great advice coming. I will chat with my machine shop/rebuilder and show him all the recommendations so we can arrive at an optimum combo for the 400.
I want to have the block checked so we know if there is an overbore and if so how much at a minimum. May get back to you guys once I know more on the engine condition. Keep those comments coming and thanks!