Cam Question for 455 SUM2801 or 2802
 

Not to start a cam war here, but have a specific questions about 2 different scenarios regarding the summit cams in a street car.

Currently have a 455 in my 68 Firebird. 7K3 heads around 9:1 CR. Headers, Perf RPM Intake, 800 cfm carb, 3.55 gears. TH400 w/ stock converter.

Eventually will have 9.5:1 CR, ported heads and a TKO manual trans. But life is real and not sure when I'll get around to this.

So my question is, in reference to the Summit cams is this:

Assuming the 2802 is an appropriate cam for the eventual configuration, will the motor be best suited for the 2801 initially and then upgrade to the 2802 when the other work is done, or is it close enough that I'll be able to drive on the street with the 2802 in the current config and just get the additional benefit with the rest of the mods.

Thanks in advance.

I n a low compression 400 the 2801 idled like a stocker. A 455 I'd use the 2802.

You can easily run the 2802 in your current combo without any problems. It will still be a mild cam in a 455 and should perform well with your upgrades. Make sure you have correct valve springs for it though.

I had the 2802 in relatively stock 400. I would definitely go with the 2802 over the 2801 in 455.

Use Rhoads lifters, with the 2802. Will work great in both engines. Plenty of low end torque, smooth idle, lots of vac.

But, most here will agree that the 2802 is quite small for a 455 with 9.5 CR & ported heads.

Some larger cams might be a Crower 60243, a Howard's 410051-14, or an 041 clone/Rhoads lifter combo. And some like the Voodoo cams. Some like bigger cams in 455's.

But, as most know, there was a very long 455 cam thread here, not too long ago, with many differing opinions. Actually lots of threads dealing with 455 cams. So, that's all I'll say for now.

Here's a couple of the longer threads.

http://forums.maxperformanceinc.com/...light=455+cams

http://forums.maxperformanceinc.com/...light=455+cams

There is absolutely no reason to run Rhoads lifters on a 455 w/2802 cam. I run one on a 9:1 455 with A/C. There is no lope at all. Plenty of vacume to run power brakes. I can idle it down really low if I want. All the Rhoads will do is make noise with that cam.

Yeah, that's the deal with cam threads. Everybody has a different opinion.

I love Rhoads lifters. The ticking does not bother me at all. Besides reducing lift & duration at lower rpm, they have a real snap ring retainer, and are said to use Hylift Johnson cores. They are also available with the Super Lube option.

Nobody is forced to run 'em. But, they are just one option, among many.

https://www.summitracing.com/parts/r...w/make/pontiac

For me the least I want to run in a 455 is 230-236 ish at 50 on like a 112-113.The CI eats up duration.Jmo,Tom

I posted a similar opinion Tom, but retracted it.
:bolt:

Yeah, a 2802 would not be my personal choice either, UNLESS price is the main concern.

"...have a specific questions about 2 different scenarios regarding the summit cams...my question is, in reference to the Summit cams..."


Not sure how many HFT shelf cams fit into the " 230-236 ish at 50 on like a 112-113 " category, besides the 041 grinds.

This Crane fits.

https://www.summitracing.com/parts/crn-284281

The Crower 60243 only misses by 2°.

https://www.crower.com/camshafts/pon...m-284-hdp.html

There are some with a 110 LSA, and the Howards 410051-14 & Erson E310031 have a 114 LSA.

https://www.summitracing.com/parts/h...w/make/pontiac

http://www.pbm-erson.com/Catalog/Ers...t_E/ERSE310031

I run the Crane Blueprint RA IV cam & love it. I have run it in both 400's & 455's & in the 455 I use the 1:65 rockers & get lots of low end TQ & it has a snap that will break you in two.

I ran the Wolverine 1096 which has the same duration as the 2802 in a 9:1 455 w/ 1.52 rockers for 10 years. Idled fine at 700-750 rpm with 15-17 in-Hg depending on the timing. Plenty of bottom end.

I have a 2802 in a low compression 400 (a little lopey idle) and a crane blueprint RAIV in a high compression 400 (very lopey idle).
I also have a .030 455 with ported 6X heads, HO intake & carb with a CC 292 magnum duration is 244 I & E @ .50 & .501 lift. Most say it's a bit too much, it idles high and I have to get the brakes sorted (a soft pedal) but that stuff doesn't bother me in the least. It's not my DD.
I have video's in my phone PM me your cell if you want them.......

Cam Question for 455 SUM2801 or 2802
 

X2, but I had a 2802. I did struggle a little with ping on hot days, but I also ran non-coated headers with no cold air intake setup.

Compression check showed 185-190ish

I would not run anything smaller


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Thank you for the responses so far. Looks like i'll drop the 2801 from consideration.

Now I'll dig a little deeper. I've always pegged the 9:1 CR to be a tweener in terms of being between cans for low compression or high compression motors. Although with the larger displacement that should aid in cylinder pressure. I guess I could back the math out to see what tight cr on a 400 would be to equal cylinder pressure. I'd assume that would make the engine lean to the higher end of the can selection (I assume these requirements in the catalogs are probably based on a 400)

I asked my original specific question between the summit cams. But if I was opening the question up, what would the recommendation be for the specs given in the original post? I'll add that I have a full 2.5"exhaust. This is a street car that needs to have good brakes. Stock bottom end so won't really see past 5000RPM. Street tires only. Probably could use to shed some of the bottom end torque. Lord knows this engine makes gobs off it. Don't mind a lumpy idle, but not too extreme. Would like it to sound meaner than stock.

Thank you for the responses so far. Looks like i'll drop the 2801 from consideration.

Now I'll dig a little deeper. I've always pegged the 9:1 CR to be a tweener in terms of being between cans for low compression or high compression motors. Although with the larger displacement that should aid in cylinder pressure. I guess I could back the math out to see what tight cr on a 400 would be to equal cylinder pressure. I'd assume that would make the engine lean to the higher end of the can selection (I assume these requirements in the catalogs are probably based on a 400)

I asked my original specific question between the summit cams. But if I was opening the question up, what would the recommendation be for the specs given in the original post? I'll add that I have a full 2.5"exhaust. This is a street car that needs to have good brakes. Stock bottom end so won't really see past 5000RPM. Street tires only. Probably could use to shed some of the bottom end torque. Lord knows this engine makes gobs off it. Don't mind a lumpy idle, but not too extreme. Would like it to sound meaner than stock. Should also add budget only allows for HFT cams. Is the RAIV too much cam for this scenario?

"...This is a street car that needs to have good brakes. Stock bottom end so won't really see past 5000RPM. Street tires only. Probably could use to shed some of the bottom end torque. Lord knows this engine makes gobs off it. Don't mind a lumpy idle, but not too extreme. Would like it to sound meaner than stock..."


Now that makes it interesting. You wanna lose some low end torque, have a slightly lumpy idle, but don't plan to go over 5000rpm. And, you need plenty of vac, for brakes.

I'm gonna guess that a 110 LSA might lose a slight amount of low end torque, and not have quite as smooth an idle. Probably need around 230 dur @ .050 lift, but no more than around 236.

Here's a Lunati 228/235 with a 110 LSA.

https://www.lunatipower.com/Product....d=1761&gid=280

Here's a 231/239 with 110 LSA

http://www.lunatipower.com/Product.aspx?id=1764&gid=279

Some on this site have recommended a 108 LSA. The Crower 60210 has 229/239 with 108 LSA.

https://www.crower.com/camshafts/pon...m-278-hdp.html

The Howards 410051-08 has 231/241 with 108 LSA.

https://www.summitracing.com/parts/hrs-410051-08

But, I'm no expert. I'm really interested in what the pros recommend for less low end torque, a lumpy idle, but plenty of vac.

Yes, I understand how that sounds where I say shed torque, but not spin much past 5000 RPM. I'm figuring that just means short shifting a cam to not use it's full potential.

At the end of the day, it's probably too much motor for the car. But it's what I have to work with. And I understand anything will be a compromise of all of the above requirements.

"...I'm figuring that just means short shifting a cam to not use it's full potential."


Yeah, you don't have to run it up to 6000, just because the cam will make power that high. I reckin it's sorta like not driving 100mph plus, just because your car will go that fast.

You DONT have to buy a box cam!You can get a cam,even flat tappet ground to what you want.Get with the right shop and if you know the lobe numbers you want you can order it the way you want it.Box or shelf cams are usually ground on 110s.Tom

"..Box or shelf cams are usually ground on 110s."

This is not for the sake of argument, at all. But, I just looked at the Crower Pontiac HFT cams. Most of them have a 112 LSA.

http://ronspontiacpage.com/reference-pages/crower.htm

Most Cranes have either 112 or 114.

Lunati cams are mixed, but have several with a 112.

None of the 3 popular Summit cams have a 110.

Comp Cams seems to be the only major cam company that grinds most of their HFT Pontiac cams on a 110.

http://ronspontiacpage.com/reference-pages/comp.htm

I dont know why dont pay more attention to Crower as I have one in my 389,just the last cam co I look at.Tom

If you want to lose low end torque, you don't want a Voodoo cam. They will make gobs of low end, mid range, and higher end power. The 227/233 Voodoo HFT on a 110° LSA, made a flat 400-402 HP from 4500-5200 RPM, in a similar 455[9.2:1]. It still made 380 HP at 5700, and 500 ft. lbs, at like 2800 RPM. The 233/241 Voodoo runs real good in a 455, and can be ground on a 112 LSA if you want.

I think that would be a great cam for the 455 Paul.Tom

It is, I was being sarcastic! BTW, the 227/233 made 14" of vacuum at 5000 ft. elevation.

I like the 233/241 better myself.Tom

From personal experience with the Summit 2802 in my 428, pretty much stock but with 6 x 4 heads : Plenty of vacuum for power brakes and AC controls. On the dyno max. 288 ft. lbs. of torque at 3600-3800
rpm at the wheels.

I ran a Crower 60916 in one of my my 455s. Nice low end and mid range, done by 5000. I prefer a mid 230's cam in a 455.

I love that cam in 455's. It really runs good. I've put it in several 455's.