Which cam do you have, & how do you like it? I'm trying to pick a cam for my GTA, & I've gotten to the point where I would appreciate some "real-world" feedback.

Ideally, those that respond would include a quick rundown of their entire pkg (i.e. which intake, heads, tranny, gears, etc. you're running) so I can see what works well with what, but any practical/pragmatic feedback would be appreciated.

Thanks guys.

 

How much HP are you looking for N/A ?

 

I'm actually not looking for a "number" - I think that the main thing I'll be looking for is the flattest torque curve possible, and the most torque "under the curve" that I can manage...
And it's not an LTR setup, I'll be using my HSR intake with AFR 195 heads.

Also, part of the reason I'm posting this is to ask "How do you like the cam you have?" & "What are it's driveability characteristics?"

Thanks again!

 

I'm running the ZZ9 which is 212 on the intake and 226 on the exhaust. I have maxed out at the 400hp mark. The cam works great. The car behaves like a stocker cam wise. However the cam is outdated and there are a lot better cams on the market these days.

I have already bought the Comp Cams XFI218 cam so I will use that on my next build up. If I were you I would get a custom cam for your set up. You might be able to get close with an off the shelf cam but you will leave power on the table.

 

Thanks 89TramsAmGTA, I appreciate that. I was thinking of something along the lines of the Comp XR270HR (218/224, .495/.502 except on a 112 LSA), but, after a little more research, I'm giving serious thought to going just a little bit bigger... <evil laugh>

Currently, I'm looking at a single-pattern cam with the following specs:

219/219 w/ a total of either .525 or .560 lift, depending on if I use 1.5 or 1.6 rockers...

I've been told that this could be the perfect cam for what I'm trying to do, which is to have a "pool-table-flat" torque curve (for predictable power application on the salt), and still pass emissions without putting in a cam so small that I may as well have left the stocker in there.

Unfortunately, I don't have one of those programs that iterates through various combinations & spits out the perfect combo for you, so I have to do this "the hard way" - by doing a bunch of research & seeing what works for other people.

Thanks again for the reply!

 

When I modified my TPI intake system it flattend out the torque curve. It looks like and LS1 on the dyno graph. My peak torque is now around 4700rpm and extends a lot higher instead of falling off. IMHO the intake design has a lot to say about the flat torque curve.

By the way that 219/219 cam is also of an old design and although it will work I think you can do better. My ZZ9 is way lazy for the duration and was developed about the same time as the 219/219.

 

Thanks for the reply. It's actually a Lingenfelter cam (LPE-74219), I don't know if it's outdated or not, but I know that the guy knew a little bit about GM's EFI engines, so I figured that I could do worse than to pick that one... I do know that I needed to find out the LSA on that cam, I think that now I'll ask them about the specs at .050", & the timing of the valve events as well.

I've tried getting dyno charts/graphs from those with HSR intakes & relatively similar combos, but haven't gotten a whole lot of replies...

*sigh* It's starting to look like I'm going to have no choice but to buy the darn $200 simulation software, despite it's limitations...

 

Yep, I was in the same boat as you. I went ahead and bought the DynoSim software. It has a feature that you can put in the acceleration lift rates of the lobes. That way you can tell the difference from lazy cams and fast acceleration rate cams.

 

I have HSR, 383, AFR heads and a 218/224....it has a mild/noticeable idle and has great power from 1300 to about 5500. Low end torque is still retained and it really wakes up about 3000. My next cam will be a 230/236 just cause it won't be my DD then.

 

That sounds pretty good, especially since I've all but decided to go the 383 route. What else can you tell me - brand, lift, LSA, etc. Do you have to go through emissions testing (like I do)? Also, is your car an L98, or something else?

Thanks for the reply!

 

I have a 1990 C1500 so its not a L98. No I don't have to go through emissions but it will pass...I don't have a doubt as long as it ain't CA. Brand is Comp Cams, LSA-112, lift-.480. Its mild but its nice for DD.

 

I bought a custom grind 230/236 112 LSA before Comp came out with that profile and I like it a lot. It's a 385 with TPIS Miniram and competition ported AFR195's. The engine makes 19 MPG with the 3.73 gears and the T56 transmission. It has 12 inches of vacuum. It overpowers the tires at 3800 RPM in first gear. It can idle in traffic all day and I really mean that: I've done the length of the Woodward dream cruise: five hours of idling in traffic. That very same day we put it on the chassis dyno in front of 150 people and made 396 RWHP.

There's a dyno sheet embedded in my SIG. It's a good cam, and I have it installed on a 108 ICL.

 

That's some excellent performance from the TBI there, Gunny!

 

Thanks for the feedback guys, it definitely helps.

Dan, I don't think you mentioned how much lift that cam has - is my guess of "somewhere in the .535 - .545" range" close?

Gunny, I continue to be impressed with your car (looks & performance-wise), & I've told other TBI owners to study what you've done...

Yenko, that's exactly the kind of thing I was looking for, thank you.

89TramsAmGTA, I just can't make myself get that software - realistically, I just don't think that I'd use it frequently enough to justify it. I think that maybe I'll call Comp again within the next 2 or 3 days, & see what it would take to get a reasonable facsimile of the 219 cam we talked about above, or what their suggestions would be for the flat torque curve I'm wanting.

Especially since the LPE salesman hasn't responded to the query I sent last week!

Thanks again all!

 

My 377 has the following solid roller in it:

262/266@.050, .665/.625 w/ 1.5's, 106*LSA