Cam and Valvetrain

[87 V20]

Ok last question for the 400....Its a 400 sbc out of a 72 impala. Ive got vortec heads, Comp 12-304-4 cam(if its worth it please let me know) and dual plane carb with my modded tbi set up, with a chip....can i run that cam with the stock valve train, push rods, lifters.

[rich weyand]

That's a good cam for that setup, I think.  Torquey, good mileage (late-ish exhaust valve opening), good dynamic compression (early-ish intake valve closure), and not too much lift for the Vortec heads.  You'll have .044 clearance from the retainers to the seals, which is almost half again the .030 minimum.  Not a high winder, but it's a nice choice for your truck.  The torque in the bottom half of the rpm range will be awesome.

Stock everything should work fine.  One note: ALWAYS USE NEW LIFTERS WHEN CHANGING A CAM.

Assuming long-tube headers and a decent dual-plane manifold, you should have about 345 lbft @ 1000, hitting 420 lbft @ 2000 and peaking at 430 lbft @ 3000, with a 300 hp peak at 4000.  Very nice.

[87 V20]

Ok thanks alot rich, I was hopin to be closer to 500 ft lbs but I was still wantin to stay at a decent fuel mileage but not to bad considerin it did just fine when stock it came out with 300 ft lbs at 4 grand haha...also thanks to everyone else thats helped with this build...as soon as the cam and lifters come in ill be throwin her all together....and just for the heck of it a guy I know has a dyno set up so ill post numbers sometime down the road for anybody else that might wanna do a build like mine...but the best part is ive got round 1100 in the whole motor...

(completely rebuilt or new) 400 with vortec heads, rv cam, longtube headman headers, modded tbi set up, dual plane aluminum intake, 5 blade aluminum fan, 4 core aluminum radiator, and all the chrome stuff(t-stat housin, alternator bracket, timin cover, block off plates,) gotta love good ole craigslist...haha.

[rich weyand]

The stoplight-to-stoplight monster, the 1970 Buick GSX 455, got 510 lbft of torque, but it would burn exhaust valves.  Hard to match that with a normally-aspirated 400.  The 1968-69 Buick GS400 got 440 lbft with the 400 cid engine, and you're definitely in that ballpark.

[454Man]

Rich you talk good about Buick... What you know about them?I've got one in my garage :-)

[rich weyand]

No, not just Buicks.  I've been studying muscle car history.  The Buicks were the torque monsters.  Wouldn't circle race with the mopar hemis, but they would blow their doors off stoplight to stoplight.  Meanest factory ride on the street back in the day.  Even the 500+ hp 1970 Chevelle SS 455 LS6 didn't have the torque of the GSX.  Nothing would touch the Baldwin Motion cars, of course, but those were not factory cars.

Actually, I should say that I'm *reviewing* muscle car history, because I was there.  I got my driver's license in, of all years, 1969.  When I was in grad school, we were buying these used muscle cars for pennies on the dollar.  Imagine how disappointed the sellers were when they got their new, de-tuned boat anchors.  1978, the year of my truck, was the worst year.  The stock C/K 350s made all of 170 hp and 275 lbft, and even the L82 Corvette only made 225 hp and 265 lbft in 1978.

The current engine in my 1978 K10 betters the original numbers by over 100 in both horsepower and torque, with the stock heads, just by cleaning up the induction and exhaust systems.  Oh, and a cam change, to the 12-300-4, the carb-oriented version of the 12-304-4 that 87V20 is putting in.

So what Buick you got in the garage?  Anything interesting?

[rich weyand]

Speaking of the Buick GS400, this car was a steal at Mecum Monterey this weekend at $14000:
http://www.mecum.com/auctions/lot_detail.cfm?LOT_ID=CA0813-160941&entryRow=42&lottype=&startRow=37

[454Man]

Ah it's just a lark I have torn down to rebuild. it's got ah 350/350 Combo that will end up being torque monster 355/ 200-4r after the heads for it hit the market.

[rich weyand]

Yes, yes, but what CAR is it?

[454Man]

72 Skylark

[VileZambonie]

You have 3 separate threads (at least that I've seen anyway) on your engine. It would suit you best to keep it in one thread.

[rich weyand]

72 Skylark

Oooo.  I *love* 1968-1972 A bodies. <sigh> That would be so fun to cram a hood full of pound-feet into.

[454Man]

Ya not to thread jack. A user somewhere named kenbetts is working on making a street strip head for the Buick 350. It should b better than just a cast ported head. Mean while I may just port my heads (I have 4 to practice on) and run it :-) the 455 will be a swap for 5 years down the line when I'm tired of the 350 :-).

[454Man]

Btw I bought my lark running and burning rubber for $900 compare that to A chevelle (that I really wanted) and you get just a body... A rusty one.

[87 V20]

haha yeah I know, I aint very good with these thangs sorry. Only time im ever on internet is craigslist and youtube