[venomcoupe]

Restoring my 71 455HO Trans Am. Auto/Air Car. Freshening up the original motor and going to add Dougs Coated Headers and looking for a Cam recommendation. is the RAIV still about the best choice? Not looking for anything crazy at all. Just a little bump above stock as this car will be driven often. Thanks for the recommendations.

[2manyT/A'S]

I don't think the RA IV cam is a good choice for a street driven car with auto & AC.....

The stock cam is really not that BAD,,,but the 69 Ram Air III (744) will wake it up nicely...

Headers on a Pontiac V8 just create extra underhood heat & maintenance issues...and unless you spend most of your time at the track,you won't really see much performance gains over the factoy cast iron Ram Air manifolds..GOOD reproductions are available from our host & are likely LESS $$$ than a set of coated headers...JMO

It's what's behind the headers that really make the difference.

[weranc55]

Agree with 2 many.

[Norwood]

I always agree with the two guys above me.....

[necdb3]

Every one I know that installs a RAIV cam on a street car is disappointed. A friend of mine had one in a 70 RAIII 4spd formula and it was a slug of the line. Once it's wound up it runs great and pulled hard but just not a nice streetable cam.

It sure does sound nice at idle though.

Dave

[Rocky Rotella]

Have some extra funds? Go with an hydraulic roller. It'll give you better performance and improved drivability. Something like a 224/236 will complement the combination nicely. It'll idle well and snap your neck off with the bottom end and midrange torque it will make!

[takid455]

Depends on several factors. Most do not install the 'old RA4 grind today. Most install some modern design with similar specs. There is a difference in drivability. XE274 comes to mind as a popular choice. Ran one in a 400 for years and had no issues. It does need compression so you would need to address that. This cam in low CR engines will have less than desirable results.

A 455 will act tamer than the 400 w/ same cam. Why? More volume to compensate for 'vacuum leak' cause by the cam's overlap.

Yes, any of the RA4 style cams kick in around 2800-3k rpm and pull hard from there.

That being said, I wouldnt have an issue as long as your trans/torque converter and rear end are gears/ valved accordingly. An OD trans may be your friend here.

[REFORMULATED]

It works well in my 455, decent idle vacuum, 14-15 Hg and great low end and mid range torque, pulls hard to 5500 RPM, nice sound at idle. It was in my car when I bought it, if I was going to install one again I would defiantly go with a roller hydro.
http://www.compcams.com/Company/CC/c...csid=1203&sb=2

[Formulajones]

Roller is the way to go. I don't even consider a flat tappet anymore unless class racing.

The original ram air IV isn't a bad camshaft, but I prefer to install them advanced about 4 degrees to help the low end and cut down on some of the "peakyness" that cam has. Especially helpfull to advance it in a low compression 455. But it's really a bandaid to compensate for what are better grinds out in the market today.

[Todd Mullin]

I posed this question not so long ago on the forum when I was rebuilding my 71 455 HO.If you are just looking for a "little bump" as stated in your post the overwhelming response that I got was to go with Summits 2802 cam. I have never heard anyone say they where dissapointed with the results of that cam or the price for that matter. Todd

[rexs73gto]

I run the RAIV cam in my 73 GTO, & I love it . I don't have any of the problems you guys are trying to put out there. My 73 runs 11:60's , it's a 462 w/ E-heads. I have RAIV maniflods Performer intake, 1:65 rockers & a Q-jet that I tricked out. I run an M-22 4 spd. I get 16 mpgs to boot. The amount of grunt I have will put you back in the seat & you have to hold on tight. The cam is set streight up with no cam advance. I have run the same cam in my 73 T/A that was basicly stock & it had great idle & it was a 4spd with A/C. I think if your haveing problems with your car & the IV cam you have not spent any time doing the proper tuning it needed.

[Formulabruce]

I have run both a comp 262H and a 268H in a STOCK CR ( 8:41) 455 HO with the correct ratio rocker arms. Great TQ and not bad economy, perfect for a driver with crappy gas. Thats the cheap way out.
Other than that I will differ, after MUCH questioning I may add, to Rocky's suggestion of a HYD. Roller cam listed above.
The "Cam Question" is always going to get the "what I use works" answer. Try to look for a build same as yours ( Stock) first, and you can throw out a bunch of Answers posted. ( no offense to posting what works for you)
Not many folks run a Stock CR engine. Rockys Idea was tested on a Stock engine and published. Mine, well you can drive it if you like ..Idles at 550 in drive.. listen to it /see it here>>http://www.youtube.com/watch?v=3F1-1...bRXwNNMl6Gjnag

[LeighP]

2802 in a +.040" 455 with headers.

Very streetable, nice mid range. I like it. Car was not built to race, so it has 3.08 gears.

http://www.youtube.com/watch?v=7nrgZ6nF2Bk

[70RAlll]

Originally Posted by Rocky Rotella

Have some extra funds? Go with an hydraulic roller. It'll give you better performance and improved drivability. Something like a 224/236 will complement the combination nicely. It'll idle well and snap your neck off with the bottom end and midrange torque it will make!

Rocky has it dead on. Had comp cams(there are located here in Memphis) make me a 224-236 roller on my 467 and it was like a new engine. The 400 was just a dissapointment , at least to me. With the roller it will light up tires rolling at 20-30 mph and slide sideways just about as long as you dare hold it.. I think CC now offers that cam, but 5-6 yrs ago, you just had to choose int/exh from their offerings. And I will have to check, it may be 224/230.. either it had good idle, great vacuum and quick response..

[70RAlll]

Originally Posted by rexs73gto

I run the RAIV cam in my 73 GTO, & I love it . I don't have any of the problems you guys are trying to put out there. My 73 runs 11:60's , it's a 462 w/ E-heads. I have RAIV maniflods Performer intake, 1:65 rockers & a Q-jet that I tricked out. I run an M-22 4 spd. I get 16 mpgs to boot. The amount of grunt I have will put you back in the seat & you have to hold on tight. The cam is set streight up with no cam advance. I have run the same cam in my 73 T/A that was basicly stock & it had great idle & it was a 4spd with A/C. I think if your haveing problems with your car & the IV cam you have not spent any time doing the proper tuning it needed.

One thing to recognize in your situation.. a 462(455 or larger) can handle the additional cam offered by the RAIV. The IV was always a bit much for a 400 ci engine. rule of thumb, every 50 CI's a wild cam in a 400 will be perfect in a =/> 450 ci engine.

[Formulajones]

I don't necessarily consider any of it a problem either. Each situation is unique but what I find in more cases than not is that the issue isn't related to a camshaft but more to the lack of tuning ability or tuning knowledge that causes most drivability issues.

The ram air IV is a cam that works, however with it's wide LSA and little to no advance ground in, and old ramp profiles, there are dozens of better choices out there.

[LeighP]

Ref my 2802 cammed 455 in an above post (actually 464)...just bumped back the timing a couple of degrees yesterday (had a little bit of detonation I could just hear). Took it out for a drive.....just rolling at about 10-15mph, nailed the pedal and it will spin just as long as you want to keep on it. Plenty of go for me, nice crisp response, too.
PS, love the Powertrax locker centre, too...works real well, hardly notice its there when you're driving.

[1971WARBIRD]

i would not be afraid to run either of these cams. also, the RAIII manifolds are great for a street car. i would go up to the 2.5 inch outlet size.
I used a crane blazer cam several years ago in a 71 HO build. been awhile, but think the specs were; 218-230. .450-465 on a 114 cl. 4speed, 3.31 gears. great runner, idled nice and great torque. 71 firebird.
used the 2802 in a 73 455 build, small chamber 4X heads, performer intake, q-jet, auto, 3.08 gears. 73 TA.
now, just to tell you what i am doing: 71 GTO body,71 455HO, ported heads, ported intake, 2.5 inch RA HO manifolds, roller cam.

[1971455HO]

I recommend reading this:

http://www.bafb.org/1968firebird.org...harticles5.htm

Everyone that has posted up is correct in their views based upon their expectations. It's true that a RA IV cam doesn't wake up until 2800-3000 and pulls like a Banshee up to 5500. If your gears put you crusin at 2400-2500 at highway speed, it ain't but a heartbeat to hit that 2800 mark when you hammer it. From a standstill, it's true, unless you have 3.90 or numerically higher gears it's not going to be at it's optimum. If you can live with a little less than stellar performance for the first half a second from a stop then it's a good choice. You have a 455HO engine, it's inherently stout from a cubes standpoint alone. I myself am running a RA IV in my 455HO, I have for years, but if I had it to do over, I would run a hydraulic roller. They give you what you want with no issues. Best of all there's no initial break in and no special additives to buy to keep your camshaft alive and well now that the oil has been reformulated.

Bottom line, there are better cam choices for daily drivers. The 068 cam is hard to beat.

just my $0.02.

Eddie

[bird72]

my last set up (now on my garage floor) was 455 with RAIV cam. D Port, 2.11 / 1.77, 9.5 to 1, headers, etc..... Based on my experience, that cam really shines in the window it should be run within.

For automatic, this is what I recommend (what I ran):

Full built T400 (aka very hard shift) with 2600-2800 stall.
9.5 to 1 preferred over 8.5
Big Valves both sides
NO Air Conditioning
3.55 gears ideal. (4.11 are carnival ride, I tried.....)
This cam begs for header type flow to run its potential... this kind of engine gets 40-50 hp with quality headers on top of rest done right.....



What you have with a well built 455 RAIV is a very cold blooded initially, marginally streetable, full romp machine. if fun is desired result, it does work. The car vibrates at a stop sign idling, the side windows shake blurring vision, and it either sits there or snaps when you gas it and it launches, which basically is mostly what you are tempted to do, is Launch...... that is what that cam is designed for really....

so it is all what you are trying to do with the car...

this same engine when I put in the white bird eventually will be de-cammed a notch and no high stall set up, more a stock tranny set up. Totally different goals now..... (Cruise vs Max)