PDA

View Full Version : Help with my new rat box



wendell
01-17-2005, 08:29 AM
I call it a rat box only because when I first started it up yesterday it shot mouse nesting and rat poison out of the tail pipes.

I'm the proud owner of a 67RS w/ a box stock 210hp 327. The plugs all looked good and there wasn't any valve noise so I'm going to leave it be. I'd like to add a 4barrel, intake, headers and exhaust. Any suggestions would be appriciated for this very mild motor.

I plan to fab the exhaust system from SS and would like to beable to support a sort of serious 406 next year. What would a 3inch X-piped exhaust do to such a mild motor?

Thanks for your time,
Jensen

Fuelie Fan
01-17-2005, 04:25 PM
Nice find!

If you are really serious about a 406 and are on a budget, why even invest in those items for your 327? If you buy parts that are right for your 327,they'll be too small for the 406. If you buy parts anticipating the 406, the 327 may become a dog. If I were you, I might go ahead and start fabricating the exhaust, as that alone wouldn't completely kill performance. I'd build it assuming headers for the 406, but then build short adapter pipes that will run from the header flange up to the stock manifolds on your 327.

If you're like me in that 1 year always seems to become three, then a comp XE262 or 268, performer RPM, 650 carb, and 1 5/8 headers into 2 1/4 or 2 1/2 exhaust would make a decent combo on that engine. The stock heads won't really tolerate much more I wouldn't think.

ProdigyCustoms
01-17-2005, 05:21 PM
If it is original, it has 291 double hump heads, which are killer factory torque heads. Not as good as new aluminum heads readily available, but pretty good for a small cube motor.
I would look at the Performer RPM air Gap, A Holley 750DP, some 1 5/8 Hookers. The headers are pretty universal, and will work good on both.
The 268 is a good choice for the 327, but is a throw away for the 406. The intake and carb will be a bit big for the 327, but will still make good power and will be perfect for a nice 406.

wendell
01-18-2005, 06:02 AM
Fuelly Fan may have hit the nail on the head. One year could be a few more. My thinking is that a Perfromer or Air gap SBC manifold will always be worth something to some one, especially if I get in off Ebay. The same might may be true for a 600cfm carb.

I don't think I'll bother to swap a cam. 1 5/8-2 1/2collector headers are cheap enough. The thing I'd like to invest some time and money into is the exhaust. Does it make sense to fab a 3 inch SS exhaust and step it down to 2 1/2 for the present set up? Good source for SS tubing and bends?

P.S. I posted some pics in the Welcome Forum: "just what this site needs"

boodlefoof
01-18-2005, 07:35 AM
Hey Wendell, I started with the same foundation you've got in my '68.

First thing I did was an intake/carb change. I went with the regular Edelbrock Performer intake and a Performer 600cfm electric choke carb. Gave the car a bit of a wake up. I later found a magazine article in which they performed the same swap on the same LF7 engine (except theirs was a Holley 600cfm). Got them 25 horses and 20 pounds of torque.

I also changed the ignition system to an MSD 6A. Can't say I really noticed any kick in the pants there, but the car ran more smoothly.

Toss on some cheapie 1 & 5/8'' headers and an exhaust... will get you some more power.

For cams... I never changed mine... but there are a few considerations...

First, the heads you have will make lots of torque with a small cam, but they probably aren't going to support a lot of high end power. They have little intake runners (around 140cc) and tiny 1.72'' intake valves (1.50'' exhaust).

Second, the original cam is tiny. I forget the exact specs but it is something around 192/198 degrees duration @.050'' lift.

That said, If I were to have swapped cams (before swapping engines) I would have gone with something in the 210-220 degree range @.050''. Perhaps the XE256, or at most the 262. And be sure to get some new valvesprings to match!

Good luck! Have fun!