Taking a cam poll...

[turbov6joe]

Ok fellas, I'm on a tall fence as to what new cam to put in my motor this winter when I yank the heads off. Here are what the mods will be, or are already. Assume if it's not listed below it's original eqiptment:

TE45a with a PTE .63 housing
Race ported TTA heads with stock size valves and 90lb springs
THDP
PAC Alky
Walbro 340
50's
Powerplate
Magnaflow muffler
Precision Industries 3800 rpm 5 disc converter (6 pump)

My TTA sees VERY little street use, most miles are a 1/4 mile at a time, so streetability is not really an issue.

I'd like you to vote on a cam and would really appreciate your opinion as to why you chose that cam. If you don't see a grind listed, throw that cam into the pot.
Thanks, I really need to **** or get off the pot ASAP!

 

[trading t/a]

are these gonna be straight up2* adv or 2* retarded etc. I vote for the 210/205 lunati 2* retarded

 

[Razor]

I'll throw this in your pot. That converter will flash to 5200-5400+ rpms easily. I would pick a cam that makes power in the 5600-5800 RPM range.

I have a 3600 and cant get my RPM's under 5500 unlocked. My 210/205 drops off in power past 5300.

So i'd be looking at the 212/212, or 218/218

BTW.. i'm cam hunting as I write this. Let ya know what I find and why.

 

[91Bird305]

I went with the 208/208 cam (not listed). From what everyone tells me, this cam is good enough for 10's and thats fast enough for my street car.

 

[turbov6joe]

I had a 218-218 in my Buick and liked it a bunch. The only downside I noticed was the low vacume which might be a problem with the TTA. One of my concerns in picking a cam is a one that needs to spin real high in the RPM range (5500+) to make power while having a stock bottom end. I agree with ya Julio, that converter on mine will make some RPM when you want it to! I had a 212-212 in the TTA until I lost those lobes. That cam pulled real hard in the higher RPM range and had GREAT idle and vacume! I've been leaning towards going back to that cam, but have a bad tast in my mouth since loosing 3 lobes last winter. Anyhow, keep the opinions comming I need to make my mind up soon.

 

[Razor]

Joe, maybe you ran too much seat pressure cuasing the cam to go south?

80-90lbs should be fine.

 

[turbov6joe]

Ya know, I was wonder the same thing as I had just put new 100lb springs on the heads when I did the 212-212 cam swap. One other hypothesis I have is that I went straight to Mobil 1 after the cam break in. I'm 99.9% convinced that full synthetic oil is TOO slick, thus not alowing the lifter(s) (mainly #3) to spin properly in their bore. Never while using dino oil did I had a problem with lobes going South! I took a poll a while back questioning those that had lost lobes and what oil they were using when the lobes wiped. If I remember correctly, something like 77% of those that lost lobes on a low mile cam were using full synthetic??? What I am doing this time around is using those 100lb springs that are WELL broke in and should be less than 100lbs by now. I'm also going to use some kind of a non-detergeant HD30w oil for an extended period of time. I usually break the motor in with that stuff and go right to Castrol dino, but this time I'm trying something different. Every motor I did a cam swap in, and that's MANY motors, I used the HD30w and NEVER had a cam lobe go bad. This last swap with the syn Mobil 1 was the first......and the LAST! Now if I could make my mind up on what cam to use. I was talking to Eric M. yesterday and he's liking that 204-214 thus far.....can't be too bad of a cam, Red's Hot air went something like 130+ mph with it!

BTW, did you have to take the Stage Right completely out of the tranny or just quit using it to get your MPH back? Two days ago I went out on my "private" 1/4 mile and made at least 12 full passes (used a full tank of alky) without using the T brake. Every one of the passes was between 119.8 amd 122.7mph according to my G-Tech Pro which is typically is pretty close to the track's MPH. The ET's were not that great due to wheel spin, however on the track it's within a tenth or two. I've been chasing down some KR that always seems to occur around the 100mph mark, can't seem to put my finger on it??? No matter how much alky I throw at it, or how little, it's still there??? I've almost convinced that it's some kind of false KR of some sorts. EM says he sees a lot of this KR around the same speed with most TTA's that send him DS files....hmmm, harmonics maybe?

 

[89ICBM]

Ya know, I was wonder the same thing as I had just put new 100lb springs on the heads when I did the 212-212 cam swap. One other hypothesis I have is that I went straight to Mobil 1 after the cam break in. I'm 99.9% convinced that full synthetic oil is TOO slick, thus not alowing the lifter(s) (mainly #3) to spin properly in their bore.


Howdy turbov6joe,

I have stated my opposition to the use of synthetic oil and given the reasons in length before on this forum and on the TTA mail list to no avail. It is unfortunate that you have had this problem but your statement of "TOO slick" is right on the money. The synthetic molecule is so slick that the additives added to the oil does not bind to the molecules. The additive package in a good 'dyno' oil as you put it, I use the term 'mineral' oil, is the same, with just 1 or 2 miner differences, as that of synthetic but, I won't get on my soap box here. Since you asked for a poll on cams, I thought I would go ahead and add my $.02. I run a D. Elgin Racing Cams 230/224 cam. It has a 280/270 duration at 4000 with a 51° overlap. The lift at the lobes is .324 intake/.314 exhaust. This is a true billet steel cam unlike all the other after market cams which are actually a cast with a hard coating, which is one of the reasons folks have lobe problems.

 

[Razor]

Joe,
I havent had any time to search down the cam.. Send me the DS file showing the KR at 100MPH. Just curious.

If your IAT are low, then the alky is doing its job. Ever considered an IAT sensor in the plenum? Just a thought.. that way you can see the IAT going down the track. Now I think your chip is using that input??? So that may not be feasable at this time.

When I get a handle on the cam selection.. will let ya know.

Same can be said of the stocker. Got guys saying they've gone 126-128 on it. But I rather go a little large than sell myself short. And use GM lifters.. Guess at 35 PSI boost any cam will work

Frank, thats a roller cam? Becuase of the drive gear on the cam snout?

 

[89ICBM]

Frank, thats a roller cam? Becuase of the drive gear on the cam snout?

Hi Julio,

No, it's not a roller cam it's a flat tapet. D. Elgin can probably make the same profile in a roller though. In fact, I talked to Craig G. at GTP about doing that and he didn't think it would help much because of the added weight to the valve train due to the size of the lifters needed. Dunno!

 

[Razor]

How bout a 224/216 112 LS rpm range 2300-6000

Will work with 90 lb springs

 

[Lunkan]

So, a 212/212 and 115lb springs is a bad selection That´s what John suggested for me.

 

[Razor]

My buddy at Reynolds ran a 212/212 on his T-type. Car ran 10.80 at 126.

Recheck the spring pressure setting. Low spring rates can cuase theyre issues as high ones can also.

I'm doing my own investigation See what I come up with.

The 224/216 is a custom grind from Crane.

.327 LL intake, .302 LL exhuast

 

[turbov6joe]

Speaking of spring rate, when I put the new cam in last time, I also installed new springs I bought from John Pearcy...which I believe he says are 100lbs. Where I might have went wrong was putting the cups back on the new springs. IMO the cups might have shimmed up the springs just enough to cause the spring pressure to be over 100lbs, and that on a pretty steep fast ramp profile cam means certain death if 1 thing goes wrong....in my case that 1 thing might have been the coolant seeping into the valley from the headgaskets. The lobes that wasted were discolored like they got hot, as well as the associated lifters. I'm going to use those springs again as they should be good and broke in by now. I never had any valve float problems so I'm assuming they're good to go. Now I sort out a tranny shifting problem that seems to have reared its ugly head recently. Anyone know what causes the tranny to delay between shifts? The car nose dives between gears and damn near hits the rev limiter???

 

[Razor]

I just went with a 212/212 112LS flat tappet.

If in the next few months I pull the motor.. i'll do a roller with the engine on a stand.

Tranny, more than likely a pressure issue. Hook a guage up to the port on its side.. take it from there. Watch the guage as it goes through shifts.

Be its losing pressure. If so.. time to drop the pan and have a lookie. Tranny fluid bath coming your way

 

[turbov6joe]

I adjusted the TV cable and went to the track today. Tranny seemed to shift firmer/quicker, but I really need to pay more attention to it to determine if the TV adjustment fixed it. On a more pleseant note I went 122mph then backed it up with a 121mph pass (not using the T brake).....1/8 mile was only at the high 92mph mark though??? I was playing with the WB and alky and gathered some good data to work off of next season.
I'm also pretty sure I will go back to the 212-212 with the 112º LS, it had great vacume and smooth as silk idle....pulled hard as well.

 

[turbov6joe]

Thanks for the input fellas, I opted to go back with the 212-212 with a 112º LS. I had this cam in my motor last year and loved the smoof idle and great vacume...not to mention it pulled HARD well up to 6000 rpm. I spoke with the guy doing my heads and got some flow numbers from him. Looks like there is not much CFM to gain past .500", and with the 212-212 and 1.67 ratio rockers, the lift will be real close to .500". The porter said that for whatever reason(s), the TTA heads gained BIG flow numbers especially in the mid lift area. He was comparing his flow numbers to the few sets of GN heads he's done and said that for whatever reasons, the TTA heads gained a lot more CFM??? He was also of the opinion that the larger intake valves would be a waste as they would actually lower the velocity with the lift I'm going to be using. Looks like the larger valves would be better suited to a roller cam. Thanks again fellas. As a side note, last Sunday at the track I ripped off a 122 mph pass and backed it with a 121....stock cam and heads....gotta make you wonder how much homework GM put into developing those motors!

 

[Quick6'n'-K.C.]

Joe-
once you bolt on those heads from maynard, you will go from 122 to 127MPH

glad you went with the 212/212 112°, it seemed to make alot of power before

take it easy

BW

 

[turbov6joe]

You know, having tried all of the grinds above except for the 204-214, I fingered I'd go back with what I know works. The 218-218 was a great cam but really needs to be spun pretty hard to make the most of its power band....and that I'm not willing to do with the TTA untill I get a girdle on the bottom end. Eric seems to like that Speedpro cam but there isn't enough trial and error out there to satisfy my need to know. The others didn't have enough lift to make the most of the new heads, so now you know how I came back to the 212-212. I can't wait to see what it will do come spring!! Once I get it back up and running I'm making a day trip to MC Racing for some dyno pulls to see where the meat of the power band is. I'd like to see a solid 4-5 mph improvement with the heads and cam, but will be happy with 2-4 mph gain; time will tell the entire story. Later skater and have a good turkey day!