[jnnyg65]

i have a decision to make. I am in the process of buying an older project 68 hardtop that comes with a 73 XC 455 and 96 heads. Heads are off and have been rebuilt, block has all the parts and is assembled but not rebuilt. I have the opportunity to buy a 68 YS 400 bare block with a crank and 16 heads not rebuilt. I am looking for opinions about what you would do in this scenario and why. I should let you know that I am not rich by any means and dont have $$$ to spend building some crazy motor that makes more HP than I got on my SAT's. My goal is to reassemble the car drop in the motor and drive it for years to come. I know that since the original motor is long gone the car's resale value is toast. SOnce it's a 68 HT auto it is not gonna be worth all that much anyways. Still, part of me would like to keep the car close to stock just in case. What would you do?

[jnnyg65]

1968 Hardtop

VIN# 24237 8Z 124786

Body Tag#
03D**** 043393************ 490287
68-24237**** BFO8664-B
19* B80****** D5

[grrr421]

the 96 heads are a good start on the 455 if its just a driver i would go with the 455 . Over bore the block and you have a 9.5 set up .

[screamingchief]

If you really wanted the engine to appear to be the more "correct" '68 400 engine,yet still have the cubes,that could easily be done all the same,but yeah there would be a cost penalty to doing such no doubt.

You certainly can get a cast 3" main 4.21" stroke crank for that '68 YS 400 block.

Add a set of PPR forged 5140 I beam rods,and some dished pistons to match the #16 heads cc's and you would have an undercover 455 disguised as your "correct" 400.

The pistons would be the most expensive piece for this,as it would need a custom dish piston,it would probably cost $500.00 to $600.00 for a set of these give or take a few $$$$.

I'd cc the #16 heads first to get an idea how big a dish I'd need,but I'd expect it to be 20 to 25 cc dish to get somewhere under 10.0:1 for pump gas use.

That is the "have your cake,and eat it too" approach.

Now,if your on a strict budget,and you really dont care all that much about the engine appearing "correct",I'd say go ahead and build the 455 cid ~ #96 head combo and dont look back,that combo has plenty of potential,it just does'nt have the "look" of the other deal.

That 455 cid ~ #96 combo will pass most folks visual inspections and appear completely at home in a '68 GTO engine bay no doubt,but as far as the pontiac "numbers" crowd,well you wont be fooling them for a second,not like that '68 engine might have them guessing.

[71 Ventura II]

Go with the CID! Yes a smaller engine can be made to run strong but why "swim up stream" build the biggest CID you can afford. Do yourself another favor, take advantage of the relatively inexpensive cost of aftermarket rods as they are now considered SOP. Good luck! JD