Third Generation F-Body Message Boards

Third Generation F-Body Message Boards (https://www.thirdgen.org/forums/)

- Tech / General Engine (https://www.thirdgen.org/forums/tech-general-engine/)

- - Cam Choice (https://www.thirdgen.org/forums/tech-general-engine/711524-cam-choice.html)

Have an 1989 Gta trans with a 350 tpi. looking for hydraulic roller camshaft Cam idle has to be rough.

Pull 2 plug wires. All of your declared goals will be accomplished.

Could you please be a bit more specific about what you want. A rough idle might sound cool but what do you really want out of a cam swap?

A "rough" idle means a high overlap camshaft. And thats power lost. The cam will want to make power where a stock TPI system doesn't want to make power. I don't know that I'd go much higher than 215° duration @ .050" on a stock intake/head TPI car. The intake just don't breath well enough.

A Tight LSA can produce a rougher idle, but rough idle for the sake of rough idle is useless. My cam has 66° of overlap. Its 231/239 @.050" lift with a 110LSA.

Peak torque is probably going to be in the 4300-4700rpm range, and peak power will likely be around 6500rpm with usable power until 6800 or so. That kind of cam gives me a decently rough idle, but its way out of the power band where TPI likes to live. You are going to handicap your setup if you want that "rough" idle.

I have heavily ported stock LT1 heads along with the intake, exhaust, and compression to support that cam.

Quote:

Originally Posted by Red_1989_GTA (Post 5844538)

Have an 1989 Gta trans with a 350 tpi. looking for hydraulic roller camshaft Cam idle has to be rough.

You would be better off putting a full exhaust system on the car. Save your money to buy all the parts to work with the cam plus you will need a tune.

Thumper cam or create your own custom one. Something like a 218/230 on a 107-108 should hit hard and run half decent to be honest.

Also if you are good with tuning, you can get a cam to "lope" by having timing fluctuate to force rpms to randomly jump up, and fall down

Comp Cams has XFI for Tune Port specific cams, but they are high lift, so if using stock heads / springs, may have to choose something else...
I'm looking at the XFI 260, again complimenting the TPI intake, not trying to fight it.... if you had better heads / intake (ported / aftermarket), XFI 268 moves the power up the RPM (peak HP at 5000 instead of 4500 with 260) range and still good enough for happy idle (so the computer doesn't get mad, but could still use a tune...)

Create your own thumpr cam

Comp high energy 3168/3163 lobes. Drop in on stock heads just freshen up springs
215/240 on a 107 .428" lift. Mild cam should have great spring life and give you that sound. Sorta like a zz4 cam with less lift, slightly more duration and tighter lca

Or 3168/3162. 215/230. 107-108 lca. Not as much exhaust duration, bit less overlap. May run abit better power wise

I Want more top end power. I have Dart S/S heads 2.02 intake 1.60 exhaust

Stock tpi is not gonna help top end with any heads. You need intake mods but if you want performance, something like a 218/224 deg cam on a 110 would work well

Quote:

Originally Posted by Red_1989_GTA (Post 5844807)

I Want more top end power. I have Dart S/S heads 2.02 intake 1.60 exhaust

Time to ditch your TPI system. I would read around the forums there is a lot of information already answered on these questions.

chinese stealth ram is a good choice.

Quote:

Originally Posted by big hammer (Post 5845040)

chinese stealth ram is a good choice.

Oh god please not!

Buy a real stealth-ram, its not that expensive. That Chinese knock-off looks like utter crap. This is like those cheap turbo headers you find on E-bay.

Quote:

Originally Posted by Thirdgen89GTA (Post 5845042)

Oh god please not!

Buy a real stealth-ram, its not that expensive. That Chinese knock-off looks like utter crap. This is like those cheap turbo headers you find on E-bay.

lol no. that's completely incorrect.

Quote:

Originally Posted by big hammer (Post 5845044)

lol no. that's completely incorrect.

No, its entirely correct. I've been following that thread since it started. The work that went into the ports was horrid.

The real HSR I bought looks 100x better. I know, I had one on my old L98.

Quote:

Originally Posted by Thirdgen89GTA (Post 5845046)

No, its entirely correct. I've been following that thread since it started. The work that went into the ports was horrid.

The real HSR I bought looks 100x better. I know, I had one on my old L98.

nope, sorry.

Attachment 330504

it's not even cheap aluminum. it's a very nice piece.

I'm wanting to build a383 vortec heads scat crank flat top pistons roller rockers what would be a good cam I want about a good 400 hp on pumpgas

I see you won't post pics of the ports. qc is a big problem with that intake and why I'd never choose it. I paid $500
Total for My stealth ram. That includes every little bit I needed to install it.

As for the 383 vortecs question?

400 hp is easy with vortecs. 400whp is not.

If you want 400 to the wheels porting or forced induction is the only way. The runners are too small, and it just doesn't flow enough to make serious power.

Forget the 383. Buy better heads instead. You'll make more power.

Quote:

Originally Posted by Thirdgen89GTA (Post 5845114)

I see you won't post pics of the ports. qc is a big problem with that intake and why I'd never choose it. I paid $500
Total for My stealth ram. That includes every little bit I needed to install it.

As for the 383 vortecs question?

400 hp is easy with vortecs. 400whp is not.

If you want 400 to the wheels porting or forced induction is the only way. The runners are too small, and it just doesn't flow enough to make serious power.

Forget the 383. Buy better heads instead. You'll make more power.

or that's just the only picture of it that i had. and they say that the ching chang HSR has more meat for porting.

Anyone using XR276HR Cam? Like to hear some feedback on it.

Quote:

Originally Posted by big hammer (Post 5845175)

or that's just the only picture of it that i had. and they say that the ching chang HSR has more meat for porting.

I have seen 3 different HSR like intakes. The Chinese knock off, a Holley version and a Weiand version. I would take the two american cast ones over the china junk. Port alignment was horribly off on the Ching Chang unit.

Just noticed that the Holley Stealth Ram is now the Weiand Stealth Ram, explains why they looked the same.

http://www.summitracing.com/parts/wn...make/chevrolet

Quote:

Originally Posted by Fast355 (Post 5845304)

Just noticed that the Holley Stealth Ram is now the Weiand Stealth Ram, explains why they looked the same.

http://www.summitracing.com/parts/wn...make/chevrolet

Getting off the OP's topic I suppose.

But for some lesson about cheap knock-offs is hard to learn. I followed that thread, I saw the pictures of the examples people purchased. As Fast wrote, the port alignment and quality is JUNK. Can it be fixed? Yes.

Does the average person who's only used to bolting parts together have the skill to fix it? No. There is a learning curve. So if you can't fix it, you have two choices. Pay someone to fix it, or live with it.

Better to spend the money on the HSR. Its legitimately the best bang for the buck intake that will support larger heads and cams. Its very similar to a LT1 intake in its flow.

Quote:

Originally Posted by Thirdgen89GTA (Post 5845426)

it's seems as though you're confusing port alignment with port matching. something you should and will be doing whether or not you buy an authentic or imitation HSR.

the thread in question is obvious that the OP had every intention of porting the snot out of the intake in question. in fact, he contacted the vendor prior to buying it to ensure that the ports were sufficient, and superior to the original HSR.

i'm not defending wang chung junk. i've seen a lot of it. but this piece is good. i am content with it 100%.

I'm not confusing the two. The port alignment is junk. it's not even consistent port to port. Some ports are cast twisted.

Holley and Weiand are the same company; have been for decades, since Holley bought out Weiand.

https://www.holley.com/brands/

For whatever reason, Holley originally assigned the Stealth Ram to the Holley brand, then swapped it over to the Weiand brand. Just a matter of the name printed on the label; nothing about the part is any different.

If you talk to old-timers whose brains aren't all ate up with old-timer's disease yet, you'll learn that the Stealth Ram is an old Holley product from around 1980 - 82 range, called the Street Ram. It wasn't a "go fast" product at all; more of a "looks" deal, for people engaged in those strange "square inches of chrome" contests you see in parking lots sometimes. It was a sort of mini-tunnel-ram, with 2 small bolt-on plenums that each held a 4-bbl carb. They intended it for use with something like 450 4-bbl carbs. It wasn't very popular; people figured out REAL QUICK that it was slower than a well-engineered single 4-bbl setup, and caused WAY MORE problems than it was worth (linkage synchronization and so forth, as well as overall poor low-RPM performance). It tanked in the marketplace. I thought Holley discontinued it sometime in the late 80s to 90 range but I'm not sure.

Here's a picture of one, unfortunately without the plenums. The guy that bought it specifically said that the 4-bbl plenums had come with it, but his forum post (not this forum) was about the base, so that was all he showed in his picture. All the same, it should look REAL familiar, except strangely enough, it doesn't have the EFI "features from the future" on it.

Imagine our surprise when THE EXACT SAME CASTING we all knew from 35 years ago showed up with a single horizontal-draft plenum on top and fuel rail bungs & attachment points!!! Of course since it's a single plenum, without all the problems of a wet flow system that the design would obviously be subject to, it works AHELLUVALOT better for FI than it did for carbs.

All that aside: a "rough idle" cam and TPI don't go together. TPI has NO high-RPM potential WHATSOEVER. Its design deliberately trades that away, in exchange for the "Mount Everest" of torque at 3600 RPM, as determined by the length of the runners. Nothing you can do to it will significantly alter that inherent characteristic. If you choose "rough idle" and run TPI, be prepared to go even slower than stock, as has been demonstrated time and again over the years. The LT4 HOT cam being the favorite example of this; slide that cam in your TPI motor, and go about a quarter-second slower. Over and over and over and over. People just refuse to learn from the experience of others.