[besserspat]

In one of my various attempts to save old Pontiac stuff to get melted and end up as walmart chinese toasters.

I have those two Pontiac 400s those seem to be just garden variety 400s but they have Odd Suffix codes.

One is a 1971 (A251) 988 block, with matching 99 heads 068 intake and 4813 N crank.

But the suffix code looks like a WT but also theres a X ( in reality seems like VV T then X)....
Maybe the first Variable Valve Timing Poncho HA!

The second engine is a 1976 (F046) 557 block with 6X-8 and its stock 4 barrel intake.

The suffix code is XS which is odd since.the only XS 400 blocks Ive ever seen were 67 GTO and 69 350 tempest.

Anyway Ive posted pictures let me know what you guess they.are.

Peter

[242177P]

71 looks like a bad restamp by someone that only
had a chisel and wanted a WT. But it kinda looks
like there's a YX hiding under it. Wallace shows a
1971 400 (265 hp), with that code.

The XS was 66-68 RamAir, the 69 350, and a late
1976 400 (170 hp)

[besserspat]

Originally Posted by 242177P

71 looks like a bad restamp by someone that only
had a chisel and wanted a WT. But it kinda looks
like there's a YX hiding under it. Wallace shows a
1971 400 (265 hp), with that code.

The XS was 66-68 RamAir, the 69 350, and a late
1976 400 (170 hp)

I cant find any XS for a 400 in the later years , 301 yes but not 400.

As for the re-stamp on the 71, I am wondering if if the original code for it isnt YT which that 400 seems to have found its way in numerous cars in 72 including GTO and Firebird.

Peter

[Baron Von Zeppelin]

The 71 400 was a 2bbl engine with #99 heads
400 4bbl heads were #96
The 068 Intake should be a 1970 dated 4bbl Intake.
Was originally one of these codes

1971 400 265 HP XX A 8.2 555 99 1-2 7041160 Block Casting # 481988
1971 400 265 HP YX A 8.2 555 99 1-2 7041160 Block Casting # 481988

-------------------------
The 76 400 XS was also a 2bbl engine , with 6X heads

1976 400 170 HP (Late) XS A 7.6 255 6X 1-2 17056160/64 Block Casting # 500557

-------------------------
Both engines were from fullsize cars.
You "might" could get someone interested in the XS block as a poser in an earlier GTO
The 66 389 version would only have 2 freeze plugs on each side.
But a 67 or 68 guy might bite on it.

[Baron Von Zeppelin]

You could cross check the date on the "76" 4bbl intake and see if it falls right in line with the dates on the heads and the block.
But it shows to be 2bbl originally.

[besserspat]

Originally Posted by Baron Von Zeppelin

You could cross check the date on the "76" 4bbl intake and see if it falls right in line with the dates on the heads and the block.
But it shows to be 2bbl originally.

H159 for the intake
A251 for the block
B161 for the heads

[Baron Von Zeppelin]

Yes, that's a very early 1970 model year intake.
Not factory issue with that 71 engine.
Expected that.

But you mentioned the other engine came with a 4bbl intake also.
By the XS code in 1976 it was 2bbl also.
Wondered if that intake was flush with the block and head dates ?
Sometimes those listings have small errors, here or there.

[besserspat]

Originally Posted by Baron Von Zeppelin

Y

But you mentioned the other engine came with a 4bbl intake also.
By the XS code in 1976 it was 2bbl also.
Wondered if that intake was flush with the block and head dates ?
Sometimes those listings have small errors, here or there.

The XS 76 400 557 block in a F046 and the intake is D076

Peter

[Baron Von Zeppelin]

Too much date stretch on a very common engine application like that.
I was just curious. Thankyou