According to the 67 tech drivetrain list, Pontiac didn't make a 400 HO in 1967. Is that correct?? I met someone that claims that he has a 1967 400 HO car with a motor code YT, which is only 400. So, is it only a 400 motor or did they make a 400 Ho in 1967??

Thanks!!!

My understanding is that in 67 the only HO offered was the standard 326 engine, but with a 4 barrel instead of a 2 barrel. That made extra horse (285 vs. 250) and was called the HO.

The 400 was a standard 400 rated at 325.

The 400HO did not come out until 68.

Does he have the PHS and has he verified the motor is original? I think he might be in for a surprise.

To my knowledge, in 1967 there was a 326, 326 HO and a 400. No 400 HO
In addition to the two 6*s
Cal

PS - I gleaned this info from the 1967 link at the top of the page which contains copies of ads...

Tall tale. Think of a car with several previous owners as one of those experiments when you tell a story to a person at the beginning of a line and become amazed how twisted the story is at the end.

There is of course, the handful of Ram Air I cars for '67

There was no 400 HO in 67. First one was 68. There is a guy in IL or MI that has a 67 400 with HO stripes and claims he has one too.

Harold, its probably the guy you refered to. His dad had a 67 400 HO with supposedly orig. HO stripes. He has a doc that shows engine code - H, and claims that means 400 HO. He is now getting PHS docs. His engine code is YT for 400 only.

Thank you everyone!!

There were also Ram Air 400's in 1967. They had a different engine code. The 68 400 HO's were Ram Air cars without the ram air

You could get rally stripes as an option on any bird but the stripes with HO call-outs were reserved for the 67 326HO and 68 350HO cars only. That could be causing the confusion.

Not true for the 68s. The 68 400HO and RAI were quite different. Like the 67 RA cars, the 68 RAIs had different carbs, dists, cams, and 3.90 rear gear standard (AC was not available). Your comment is true of the 69 birds however (in standard form).

But what is the difference between a 68 400 HO and a RA1 besides the air intake?

Carb numbers, head casting numbers. All most the same things listed above.

the 68 RA1x had different Numbers for the carbs, dists, cams, and functional ram air parts, but the HP stayed the same.
As far as HP, they still were the same motor. In 69, the HP Also changed between the 400, HO, and RAs motors.

Those are factory ratings, not real HP. But to your point, and to be honest, I don't think there is a lot of real HP difference between any of the D-port 400s (std, HO, RAI, or RAIII) by themselves. The difference is really the entire package. The 67 RA and 68 RAI were purpose built packages set up for the track with 3.90 gears, cammed and tuned for higher RPM performance. The 69 RAIII was really just the functional ram air scoop option added on to the 400HO. The small HP bump was probably more an attempt at marketing that option than a real HP difference.

The RA supposedly has a slightly more radical cam, and different carb numbers which I would think would mean different jetting.

Mine has the 3:90 gears and close ratio Muncie 4sp as well.

I am curious as to how different the jetting and cam really are on the RA1 motors from the HO.

From what I recall, the 68 400HO 4-speeds used the 068 cam (212/225 @ 050, 116 LSA) while the RAI 4-speeds used the 744 cam (224/236 @ 050, 115.5 LSA).

As you note, tranny selection plays a factor. I believe the RA II autos came with 068s, not sure about the RA Is.

Thanks for the info guys, mine has a pronounced lope over other 400's that I have heard run and I imagine the RA1's are even more so.

I would think that the 224/336 would provide a little more low end torque than the 212/225. (Not that any Pontiac lacks torque)

Duration is the amount of time in crankshaft degrees that the valve is off the seat (open). Generally the power band moves up the rpm curve as the duration gets larger, and you lose low end.