kilrb

I am ruthlessly consuming information on cam/head combinations, and I am really beginning to lean towards sticking with stock exhaust manifolds on my 99 FRC Vette (or going to Z06 manifolds). I have seen a ton of info on this board regarding the Cheatr package, and the GT2-3 cam, both of which run well through stock manifolds. The question I have is this... From what I have seen, the smaller GT2-3 seems to run just about as well as the Cheatr cam, and I wonder why. I have seen Patrick G's dyno graphs, a GT2-3 cam only dyno graph, and a GT2-3 with Lingenfelter heads. For whatever reason, the GT2-3 seems to be pushing out just as much, if not more hp than the Cheatr with, or without heads. Can anyone help explain this phenomenon? The two Vettes I saw with the GT2-3 had Z06 manifolds; would this be the deciding factor? I also saw a dyno graph of a Vette with the Cheatr and Patriot heads, which was identical to the GT2-3 cam up to about 4.5k, and then was only maybe 5-10ft/lb more than the GT2 to redline.

Cam specs are Cheatr: 214/230 .601/.578 117 LSA
GT2-3: 207/220 571/.578

Here's a link to the Z06 clone with the GT2-3 cam and Lingenfelter heads.
http://www.z06vette.com/forums/showt...t=83571&page=5

Here's a link to Patrick G's dyno graph with the Cheatr/AFR heads.
http://guerragroup.com/2000TA_dyno1.jpg

YankeeVert.

Andy (the guy in the link you posted) was using high flow cats on his setup. He also mentioned that he got 421 HP out of his project before he finished.

kilrb

Yeah, I had seen that he used high flow cats. I don't know for sure what they are worth, but I would guess not more than 5 or 10hp. I actually sent Andy a PM at Z06vette.com, but hadn't heard back from him.

Matt D

iTrader: (49)

I am looking at those two as well as LPE's GT-11 (215/231 .631/.644 w 1.7 rocker 118.0 CL)

The GT2-3 has the least amount of overlap of the three, so I assume it would sound the closest to stock. I want to throw one in my car with true duals dumped before the axle.

Steve Bryant

iTrader: (1)

Both cams are in the same ballpark regarding lift, duration and LSA. It's very reasonable to expect them to have similar power bands. The GT2-3 is probably more streetable. What are your goals for your car? What kind of setup do you have now and what to want to migrate toward?

Steve

silver01z06

sticking stock manifolds is not the way to go. get yourself a good header be happy.

SSmoky01

Either one of those will benefit from headers. Is there a certain reason why you are not wanting headers? Your factory cam will benefit from that mod.

mullenh

iTrader: (1)

the vette manifolds are better than the f-body, they do flow pretty well. The cams selected were designed to work with stock exhaust manifolds (cheater)

kilrb

I have toyed back and forth between a larger cam with headers, and a sleeper cam through manifolds, and I'm leaning more towards the stealth effect. If I go with headers, I really like LG's G5X1-E cam 228/232 57x lift on a 115LSA. I have heard a clip of that cam idling and revving on a Z06 with stock Titanium exhuast, and it sounds pretty good. That, and it puts out some wicked numbers, with a broad torque curve. I don't like lope, and it is surprisingly tame for its size.

That said, I'm not all about peak horsepower, and I'm not really that in to loud cars. My FRC had B&B Bullets on it when I bought it, and I didn't care for the volume, or drone. My car feels great stock, so I'm not concerned about going overboard in adding power. I would love to be able to hit 400whp with a Cheatr or GT2-3 through stock manifolds with a good set of AFR or Lingenfelter heads. That would be close to 100 additional whp, which should be plenty (I know, it's like an addiction, and it's never enough). I may even go with a cam only, and add heads down the road...

I know it's not a popular opinion on this website, but I don't want my car to be all that loud. I dig it, and all, but not for this car. I am well aware that I am giving up 30whp by not going headers, and I'm ok with it. I'll put on the flame-proof suit and wait for the name calling.

I have a 99, and I believe they have a more restrictive manifold than the 2001 and above, but it still may be less restrictive than the F-bodies.

PA Z06

Sent u a PM

kilrb

bump

Steve Bryant

iTrader: (1)

I think the cam is a coin toss. If you want headers and a broader torque band, go for tri-Y. They improve performance over exhaust manifolds and are better than shorty headers, but they are not as peaky as long tubes.

Steve

Bob25thTA

This is my dyno chart on my 03 vette, CheatR cam and Patriot assembled 243 ported heads. The only MODS are MAF screen removed and holes drilled in intake cover with WIX paper air filter.

Signal7

Don't worry, I've been doing some serious thinking lately about this as well...I think I've also made up my mind not to get caught up in a horsepower frenzy...I don't want to be another guy breaking his "weak" transmission and rear end every year...I love going to the track and downloading videos on the internet of crazy F-Bodies but that's just not what I want out of my own car...I got the Pacesetters with ORY-pipe last summer and am thinking of swapping them for stock manifolds/shorty headers in the future...And when I get the money a nice GT2-3 or CheaTR cam sounds like it'd be a good mate with a Yank TC and the bolt-ons I have!

These are such nice cars from the factory...For me, a few appearance mods, a few bolt-ons and maybe a mild heads/cam combo are perfect way to top off these cars!...

mullenh

iTrader: (1)

i agree it is what you want that counts

Fire-formula 93

iTrader: (1)

I like they way you think. I had longtubes also and recently switched back to stock manifolds and gutted cats with TSP rumbler. I love the sound know, couldnt be happier but I want to increase the power to 350 or more without anymore exhaust modifications. I am considering the cams mentioned, I still need to so some research on the gt2-3 cam but the cheatr requires the dual valve springs. I am on a real budget so I would like to try to get a cam that doesnt require the duals, but makes great power with stock manifolds.

kilrb

It's funny, but after all this mental masturbation, I wound up ordering a 224/224 on a 112 with a set of 5.3 liter heads. I'll be going the route of non-sleeper with headers after all. I just couldn't live without the low-end torque you give up with exhaust manifolds.

Check with a member named Ragtop 99. He has a stealthy, yet torquey cam that works well with manifolds. He dyno'd 344 on a Mustang dyno, which would be well over 350 on a dynojet. I imagine it's a fun cam. Here's his post... https://ls1tech.com/forums/showthrea...=440051&page=3

Ragtop 99

iTrader: (7)

With a quiet catback and stock manifolds & cats, there will not be a significant change in loudness between a -15 cam and a -5 overlap cam. If your car is too loud, stick extra bullets in the ehaust and enjoy the power from the higher overalp cam.

kilrb

Hey, ragtop, I guess you see I went to the darkside... I appreciate your help with the cam specs. In the end, the power left on the table just got to me. I'll be installing the 224R and 5.3L heads in the next few weeks. I'll be sure to post my results.