I'm sure many have seen some of the comparison pictures on the ZZP website, or else where, but I wanted to make my own here for Fiero owners, by Fiero owners!
Here I have a stock cast manifold, nothing has been done to this manifold, 100% stock. Next to it is the ZZP Power-log. The difference is this is one of the older P-logs, as it is not made of stainless-steel. I got it used for cheap. I think the shape was changed as well, but it fits exactly the same. The welds are great and show no signs of any cracking. Now, take a look at the differences. Pretty crazy how bad the stock cast manifold is, compared to the P-log. There is a very noticeable weight difference just by picking each one up. I don't even need to talk about the ports on each of them...
Next, I decided to cut the cast manifold in half to show really how bad it is. Even though I knew what I was going to find, i was still surprised to see exactly how thick that manifold is in person after it's cut. This is why they are so restrictive! It looks "OK" on the outside, until you find out how small the volume really is due too how thick that wall is. You can see in the pictures too, is it very rough on the inside. The ID of this cast manifold was around 1.6 inches, with an average wall thickness of .180 inches! ZZP claims theirs to be 2 1/4". ZZP also clamied a loss of 5lbs from the cast manifold, I believe it!
This is pretty bad as well, very odd shape on the cast manifold.
I painted the ZZP manifold after this comparison, so It looks MUCH better now.
I highly recommend getting...something! Anything is better then that stock manifold if you are looking for performance, P-logs or headers. The p-log is really good for a Turbo, just make sure you get the stainless steel version. IMO, rarely do you see a log style manifold that has more flow AND weighs less.
[This message has been edited by mattwa (edited 03-05-2012).]
IP: Logged
05:01 PM
PFF
System Bot
fieroall Member
Posts: 403 From: Great White North Registered: Feb 2008
Yes headers like ZZP's or TOG's are better then the Powerlog, but they really don't fit well in a Fiero, and of course forget about having the lower half of your trunk. I know several don't care about that, but I do for the time being.
If/when I go turbo like you and Justin did, yea I will be keeping my stock rear manifold, but keeping the front cast manifold is just a horrible idea for flow.
[This message has been edited by mattwa (edited 03-05-2012).]
IP: Logged
07:42 PM
Fierobsessed Member
Posts: 4782 From: Las Vegas, NV Registered: Dec 2001
I bought the normal front power log, and the "turbo" rear power log. I plan on using them to make a Fiero style routed exhaust. It really looks great on the engine too.
I bought the normal front power log, and the "turbo" rear power log. I plan on using them to make a Fiero style routed exhaust. It really looks great on the engine too.
I wanted those until I saw the claimed 10hp increase was like above 5k rpm. Now I see in their website that it doesn't seal good and cracks. Not sure I want to go there.
IP: Logged
08:38 AM
PFF
System Bot
raljep Member
Posts: 20 From: Westminster, Colorado Registered: Aug 2011
I wanted those until I saw the claimed 10hp increase was like above 5k rpm. Now I see in their website that it doesn't seal good and cracks. Not sure I want to go there.
The stainless steel ones don't have nearly as many crack problems as the steel ones did. In my case, it's easier to go past 5k rpm, being a manual with a 3.94 final drive.
IP: Logged
12:45 PM
Mar 10th, 2012
Francis T Member
Posts: 6620 From: spotsylvania va. usa Registered: Oct 2003
With this application I'd rather use the stock cast headers whereas they may be a bit smaller inside but the junction between the runners and the log is much smoother with the stock cast units; thus, I think you will lose some velocity with ZZP.
BTW you can port runner flanges a little with the stock units.
That's true, but did you see how rough it was inside?? It's like touching 60 grit sandpaper! That would reduce velocity right there. Even with the porting, it still "necks" pretty bad into each runner.
Plus like I said you lose 5lbs.
And a "bit" smaller? The ID is 1.6xx inches compared to 2.25 inches.
[This message has been edited by mattwa (edited 03-10-2012).]
IP: Logged
12:29 PM
darkhorizon Member
Posts: 12279 From: Flint Michigan Registered: Jan 2006
With this application I'd rather use the stock cast headers whereas they may be a bit smaller inside but the junction between the runners and the log is much smoother with the stock cast units; thus, I think you will lose some velocity with ZZP.
BTW you can port runner flanges a little with the stock units.
Right
quote
That's true, but did you see how rough it was inside?? It's like touching 60 grit sandpaper! That would reduce velocity right there. Even with the porting, it still "necks" pretty bad into each runner.
Plus like I said you lose 5lbs.
And a "bit" smaller? The ID is 1.6xx inches compared to 2.25 inches.
The Fiero 2.8L has powerlog type manifolds on it and when you port them they do improve performance.
As for the cracks; that was mostly a problem on the early manifolds. ZZ Performance has some pretty impressive dyno data about the powerlog from a customer on their website. It looks like the powerlog adds both horsepower and reduces KR numbers. Do they work? I have yet to install mine so we shall see. The ports are bigger that the stock manifold so why shouldn't they work? They give a 30% increase in ID size. Check this out: http://shop.zzperformance.c...nless-Power-Log.aspx
One other point. On a turbo application I don't know how much the powerlogs would help as the main restriction becomes the turbo itself not always the manifolds. I have always been of the opinion that for fast turbo spooling you can't go hog wild on exhaust pipe/crossover pipe diameters as it slows down the exhaust flow.
------------------ " THE BLACK PARALYZER" -87GT 3800SC Series III engine, custom ZZP Intercooler setup, 3.4" Pulley, Northstar TB, LS1 MAF, 3" Flotech Afterburner Exhaust, Autolite 104's, MSD wires, Custom CAI, 4T65eHD w. custom axles, HP Tuners VCM Suite. "THE COLUSSUS" 87GT - ALL OUT 3.4L Turbocharged engine, Garrett Hybrid Turbo, MSD ign., modified TH125H " ON THE LOOSE WITHOUT THE JUICE "
[This message has been edited by Dennis LaGrua (edited 03-19-2012).]
+ Some ER Rockers. Good post man.
