It's not the looks of the stock manifold I'm concerned with, it's the weight of it mostly...the stock 2 barrel manifold that came off my motor weighed a ton compared to the Weiand that went onto it...I'm gonna keep the Weiand for now, in the next year or two I might be making the switch to mechanical injection, and possibly build up an entirely different motor for the car in that time...I think I'm set for now with everything guys, thanks a TON for all of the advice and input...it was well appreciated...
Ok, so I found a Howards cam for $65 shipped, here's the specs... # howards 410011 Intake lift .422 ...Duration 204 @ .050.... Exhaust lift .444... Duration 214 @.050 Lobe separation 112 ... intake lobe centerline 108 Seems a little odd compared to the Melling 068 specs, I'm gonna look into it some more and see what I come up with...I'd like to give it a shot unless you guys see something wrong with it...
You made mention earlier on that these parts are all you have. Then just use em. A different intake (that you have to buy) won't make a difference that you'll actually feel in the seat of your pants. Just rock the stuff you have. The 400 has plenty of low RPM "grunt" to pull that 3.23 gear too. 268H Comp if I had to suggest a cam other than a RA III. I think the IV might be a taste weaker at the lower RPM's
my turn!!! What this guy says because he has already done the work for you. So what manifold should you run? Unless you can safely run your engine to at least 6000 RPM and develop some power in the upper RPM ranges, and your car weighs no more than 3400#, and you have a four speed or a converter that stalls to at least 3000 RPM, and you are running 3.90 or slower gears, your vehicle will run better with a stock cast iron or a Performer manifold. (A Torquer II may run as well but will lose low speed throttle feel). Go here. http://www.dingdongtx.org/1968/jharticles/jharticles14.htm Serious, when I bought the TA this engine came out of that is now in my wagon my friend came over and slept on the lawn until I removed the Edelbrock that was on there. He breathes Pontiac. Youre going to have the intake off anyway for your head change.
Ok, so I might lose miniscule amounts on my ET and MPH...big deal, I already have an intake and I'm not shopping for another one right now...this isn't a drag car, and even if it was it's not going to be a compe***ive one...EVER...so unless my Weiand intake somehow makes me run 4 seconds slower then I'm not changing it for now...like I said, eventually I'll probably be running injection, so until then this intake will get me by...and if it seems like I'm a little pissy right now it's because I can't find a single ****ing place online that sells a cam and lifter kit with what little money I have right now...and if it is in my price range, they **** you on shipping and handling...I'm gonna go get some food...
I am cracking up!!! you are here for our entertainment. Serious, sorry, I should have read more. I did think you were going after whatever performance gains you could achieve for the best value.
It's no problem...I just want this motor to run healthy without falling flat on its face like most poser g***er lopey cammed cars out there these days...I found a S***mit 2801 kit for cheap...thanks
Ruiner, Dad has lot of good stuff in his book and I suspect he can give you some more good advice to go along with the HAMB info from above. If you are interested, email me thand@kc.rr.com and I'll do what I can for you. Tom Hand
Thanks Tom, I'll drop you a line tomorrow...here's a quick question...what compression will 8.2 350 heads be on my 400...I'm guessing with the extra stroke on the 400 it'll be somewhere around 8.7, is that correct?
Ok, I feel dumb after finding out the 350 and 400 stroke is the same, but I did calculate the C/R will be 9:1...are the 350 and 400 crank and rods interchangable?...if so I'll keep that '71 short block and build it up to a 400 as a replacement full on drag motor when the '76 motor pukes out...
The 350 and 400 rods are interchangable, but you wont be able to bore the 350 out to get a 400 unless you get a stroker kit from Butler or somebody, hardly worth the effort for the cost involved IMO. With all the good aftermarket rods available now, especially if your going to build a drag engine , I wouldn't think of reusing the old rods . If the 350 heads are small valve, I would get the intake upgraded to a 2:11 valve for more flow.
The heads are #94's, I thought the blocks were all the same for 350, 400 and 455? Is the crank from the 350 not interchangable with a 400?...If the 350 block won't bore out to 400 then it's useless to me...
You can run nitrous with ANY cam. It's performance will differ with each grind. More importantly is HOW MUCH nitrous, and what pistons and head gaskets.
Id be getting with Tom Hand, if his Dad is Jim, he's my hero! Im following his HO Racing Speciaties Book to build a motor for my 71 lemans Wagon.....making a 71 lemans wagon with a GTO nose & full inerior run mid 12s with all GM Parts, and a Q jet on pump gas should get some respect. He knows his ****!
Why are people so obsessed with the RAIV cam? They were suggesting it to me with my low compression smog motor...I think half of them just want to have something to say rather than knowledge of the right cam to suggest...
the ram air iv cam runs great usually with gears and compression and cubes. when it came out in 68 it was in 4 speeds with 4:33s. don't think 3:90 was an option. jim hand has made it work in his wagon, 455 low compression and 3:31 or 3:55s i forget. get his book, he's the pontiac guru along with tom.
Because of the bad*** idle and known performance on an upper rpm level, of course if thats all you want to do is idle around than your ok. You get away with the 041 (RaIV)with more cubes like a 421,428 or 455 than a smaller cube 400 especially low compression. The 041 is also Edelbrocks Performer RPM camshaft. Although they list this cam starting at 1500 rpm for some reason.
I dont get it either. Having been a Pontiac guy for 27+ years and had at least 15 Pontiacs, one with 536,000 miles on it now and 3 engines later, having a non ported 400 doing mid 12s in a 3810 lb car and being president of a 200 member Pontiac club for two years and being alot of their go to guy to fix their cars, I just dont get it. I have heard and witnessed the infamous RA IV cam in a smog 400 more than once. It sounds good but wont do **** on a low compression motor. I still have 4 Pontiacs but am concentrating on my 1929 Whippet with a Hemi now.
Agree with the last posters. The RA IV cam is ONLY a good cam for big cubes, high revs and usually low gears. Nasty idle for anything else, but will fall on its feet.
this is an old thread but worth reviving. With that combination you want a mild street cam. The original Pontiac 068 cam would be a good choice, or the Comp Cams 268 which has a little more duration at .050" and slightly more lift. The RA IV cam would be too big for those gears and low compression and stock converter.
that is correct, the RA IV cam is dead below 3000 rpm, I ran one for years in a 400 with casting #12 heads, factory iron intake/Qjet, with headers, in a Firebird w/3.70 rear gears, and TH350 trans/stock converter. It had 9.6 CR and was bored .030" That combination would run good but was on the ragged edge for pump gas, would ping sometimes depending on where I bought the fuel, and absolutely had to have premium. It ran 14.10's at 100 mph and weighed 3650 lbs. at the track. I also put a RA IV cam in a 350 with only 8:1 CR, and had bone stock '71 455 HO round port heads, with the factory cast iron exhaust manifolds, and the factory aluminum 2 piece intake, which I ran without the intake heat crossover. That was a finicky combination and done for schitts and giggles with a used worn 350 Pontiac block I had laying around. The heads were done though, with new valves/springs/valve job, and Qjet carb again. With a Muncie M20 and 4.88 gears it also ran a 14.10 but at 96 mph- in a heavier 1970 GTO. But I would not recommend that RA IV cam in a low CR application. The RA IV grind would be a good one if you had it ground as a SOLID FLAT TAPPET CAM like the #10 McKellar 421 Super Duty cam was, but tighten up the lobe separation to 110 instead of 114. After driving that cam around for many years in a 400, 3.70 rear gears were "barely" enough, and it really should have 3.90 gears, which is what Pontiac put behind it in the Firebird RA II 400 cars w/stick shift. In the heavier GTO's they used 4.10's or 4.33's with the RA IV cam, but if memory serves if you ordered A/C they gave it 3.90's- but as you said, the IV cam is dead below 3000 rpm, then it comes in like gangbusters up to around 5500 rpm. It would be an ok cam for a 9.25 CR engine but today there are better cams out there, and actually an 068 or Comp 268 cam would be a better choice, if you have mild gears like 3.23 or 3.55 back when I was a kid just started driving, I had a Catalina with 389-2bbl and 066 cam, and that thing was a torque rocket in that heavy car, so you are correct in stating, you don't need a big cam- it would not burn the tires because it had such high rear gears, but that actually helped it because it would hook and GO like hell
I went to a solid cam in my 455 and would never put a hydraulic in a street motor again, but that's just my preference- you have to be willing to set valve lash on a regular basis, and limit oil to the top end with the correct lifters or pushrods with small feed holes, but the engines do make more power with a solid lifter cam, because then you are getting the true valve action, not dampened down by the hydraulic lifter.
I ran all 3 of the Summit brand cams, 2800-2801-2802 in Pontiac 400 and 455 engines. The 2800 is way too small and runs out of breath too soon. the 2802 is bigger and lopey but lacks torque- and actually the 2801 would smoke either one of them. The 2801 in a 455 was a real tire burner and ripped your head off but ran out of breath at 5200 rpm as if it had a rev limiter on it- this was with unported D-port big valve 2.11/1.77 heads. If I had to choose for a 400 it would be a 2801, but truth be told the 2801 is not a "clone" of a Pontiac cam, the duration seat to seat, and at .050" is changed, it's a more modern cam design, and also seems to have a tighter powerband- because mild stock GM Pontiac cams typically had a very wide power band, even the mild ones would rev high and keep pulling. I'd run a stock 068 instead of a Summit 2801 to be honest. If I went to aftermarket it would be a Comp 268. The 2801 was a good cam but was kind of generic compared to the other 2. Keep in mind the McKellar was a brilliant engineer and those cam specs came about after many days, months, years, hours on the dyno testing engines. He knew his schitt, and he was so good that there isn't much you can do to improve over his cams, even with modern technology- for a street driven Pontiac. Now race is another story, the newer race cams whip the old stuff. On the RA IV cam, John DeLorean thought it was a "piece of junk" (quote his words) because it killed torque below 3000 rpm- but it was basically a WOT drag racing cam developed for the 421 Super Duty with very low gears, and high rpm, and was first a solid cam #10, before they made it a hydraulic cam IV. So that tells you what the IV cam was really made for, drag racing with low gears and high 5000-6000 rpm peak.
I agree with this. The RA IV cam is a little on the aggressive side IMO for a A.T. car. I always use the 9779068 equilivent camshaft. Remember Pontiacs are not a high RPM motor, maximum on a stock bottom end is aroud 5500. The 541000 conn rods are cast and known for breakage at high revs even though they were used in the Ram Air motors. You can run them higher, but not a good idea in stock configuration. Seen too many Pontiacs with the side of the block blown out when people think they can run them like a Chevy. I'm running one in a 4000 lb big car with a Muncie wide ratio, 3.42 gears with 235/70-15 tires
We ran a stock bore 455 with #12 heads and the RA IV cam on the street back in 1992. This was a heavy 1971 Lemans Sport that weighed 4000 lb. w/driver and aftermarket wheels, stereo, etc. It had a Qjet, iron intake, 3 tube headers, stock converter on a TH350 trans, w/3.70 gears. It ran 13.80's at 98 mph on pump gas with pistons that had the 8 valve reliefs, but it was still touch and go with compression and unleaded pump gas- we had to back off timing to 27 degree total or it would ping- yes it was a tire burner, but actually even a RA IV cam is too small for a 455. That engine starts to wake up at 240-250 degrees duration @ .050" and prefers a solid flat tappet lifter or solid roller cam. We then lowered the CR with 6X heads, installed a roller cam, and it ran 13.40's We then put Edelbrock heads on it and a Victor intake and BG 950 cfm carb and it ran 12.30's at 110 mph on pump gas, with 9.9 compression- car also weighed 4000 lbs. but you could drive it to work every day- it had a relatively mild 242 duration cam @ .050" Comp solid roller- this car had a Richmond 6-speed and 3.70 gears We also put another Comp solid roller in a 1976 T/A that weighed 3900 lb. w/driver and 3.70 gears, and ST-10 stick trans, it ran 12.30's at 114 mph- this car also had Edelbrock heads but only 9.25 compression, but a better driver and more aerodynamic car. Also ran on pump gas 93 octane without pinging. Once you put a solid cam in a Pontiac, the hydraulic cams look like child's toys in comparison. Yes sure there's guys that run 11's with a RA IV cam but they have to tweak the combination for years to get it to run that time- we were running stock cars with stereos, full interior, etc. in them, stock springs, heavy mag wheels, heaters, etc. in them. Bone stock cars, just souped engines. I did see a 1970 Lemans at the track running 11.90's with a 455, casting #16 heads, Edelbrock Torker I, Holley 850 DP, 3000 stall converter, TH400, and 4.11 gears- gutted interior, slicks, but the heads were heavily ported, and it was towed in and had to run on race gas 110 octane. He was hooking better but his mph was actually around the same as our street cars. He had air bags, 90/10 front shocks, no sway bars, no heater, etc. and was a few hundred lbs. lighter- and was running a spool.
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