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View Full Version : Quick! I need an opinion: 455 or not?



Ishmael
09-02-2004, 06:23 PM
I have the chance to buy a pontiac 455 and th400 for my 68 Firebird convertible for $750 Canadian (think about $600 American). My car currently has a sbc350/th350 combo that needs freshening. I would love to get this engine and they are getting really scarce around here. What I'm wondering is: 1) is it worth it for go fast parts? 2) What kind of changes will I have to make (other than trans mount location, engine mounts and springs) ie: drive shaft length etc? 3) Is the weight so much more that it would effect handling badly? 4) How hard is it to find an R4 tranny to mate up with it? 5) Would you do it? Lots of questions I know but this engine will be gone probably by tomorrow night.
Thanks
Scott

gmachinz
09-02-2004, 06:33 PM
Scott, about the only slight drawback would be the added weight of it. It will throw off the balance some without compensating with stiffer rate springs for example. You can easily get a hold of an adapter plate to go from BOP to a 700R4. And big-block Pontiac performance stuff is more expensive since it is the odd man out in terms of popularity but that does not mean it isn't worth the money! I'd say grab it and stuff it! Besides, anything big-block is going to cost you anyway so you might as well dare to be different! I had SERIOUS thoughts a few years back of ordering a 572 Blackbird special form Larry Kruzick-the Cadillac Man and stuffing it into my '70 Monte! It was basically a stroked 500 cu motor that was approaching 800 hp! Then reality set in. :candle: -G

Ishmael
09-02-2004, 06:46 PM
Thanks for the quick reply! I'm thinking the gobs of tork and the "455" on the hood would be worth it but I don't know if the cost (I'm on a serious budget) and changes to be made outweigh the wow factor .

cjhutch
09-02-2004, 09:08 PM
Scott, I'm a pontiac man myself and currently building a 440. I say go for it. The amount of torque that you can get from a LARGE JOURNAL (notice I didn't say big block) pontiac is amazing. Just remember the weakest link is going to be the rods. What I mean is the stock rods have limitations as far as how high it's going to rev and how much power it can handle. True the parts are more expensive, but hey it goes with the territory. Living up there in Canada you have one of the best in the game to communicate with in SD Performance. I've had a set of heads ported by them and they did a great job. Good luck with the purchase.

spanky the wondermuffin
09-03-2004, 06:26 AM
i'm working on a 68 bird and would grab it in a heartbeat.just for cool.

Ishmael
09-03-2004, 09:02 AM
I'll see if I can get it home even if just to sit on the stand and look at. Thanks guys. Sometimes cool outweighs common sense. If it isn't sold I'll pick it up and figure out how to put it all together. That's the point of this hobby.

Drewhelm
09-03-2004, 01:23 PM
To answer a few more questions. the Pontiac TH400 combo will require a different front yoke on the driveshaft and having the driveshaft shortened about 1/2 - 3/4 inch.

Oh, and the Pontiac is not as heavy as a BB Chevy.

I did the same swap within the last 2 years and have NEVER questioned my decision. There is nothing like standing on the go pedal of your Pontiac 455 at about 30 mph and feeling the rear wheels break loose.

My name is Drew and I'm hooked on Pontiac......469 cubic inches. :help: