Friday, February 18, 2011

Clearance Measurements

I was talking to a fellow member about the mid-muffler and the discussion ended up around how much the muffler actually 'sticks out' and how much clearance I have. It's been going on almost 2 weeks now since my mid-muffler install and keeping away from known trouble areas (e.g. part of my driveway with a tree root under it ) i haven't had any major scrapes (just one teensy tiny one). So it was time to crawl under the car and see exactly what's going.

At first I did the super-duper-scientific method: I stood a small piece of wood up under the car and marked the level of the lowest point on my cats (my previous lowest point). Then I moved the block to the mid muffler and did the same. Looking at the marks they were within basically a few millimeters of each other right around 3". So officially I have 3 inches of clearance. Of course that is with how much my car is lowered which is who knows exactly how much...  The discussion then circled back to 'but how much does the muffler stick out' etc because every one's car is different as far as how much it's lowered. And really stuff like "651 mm" as described by Pedders (measured to the bottom of the rim) never made any sense to me since i'm running 20's.I know there's probably an easy conversion i'm missing (add/minus 1 inch probably?) but I figured I'd measure on the body instead.

Some quick measurements came up with the following points
Front Driver Side wheel - Straight up through center from Ground to Fender : 27"
Rear Driver Side Wheel - Straight up through center from Ground to Fender : 27"
Front Door Line - Eyeballing while standing from the edge to the ground: 6"
Between Front/Rear Door Line - Again eyeballing while standing; 7.5"
In front of rear Wheel well - again eyeballing; 9"

Now the Line I was following was the 'upper' line (if you paid attention while washing your car you know it slants up while it curves under. I've made the following photoshop to make this a little clearer:

So that at least gives a baseline for how much my car is lowered etc. which if someone else were to measure their car would give a possible indicator how the muffler would sit. (e.g. say that mid part is 9" instead of 7.5 it'd be safe to assume they'd get at least 4.5" of clearance depending on fitment etc.)

For the final measurement I went back under the car and measured from where the cross-member used to sit to the ground. The actual Measuring Tape is about 2.5" tall when it sits up like in this image:

 So the total clearance from the ground to the crossmember is about 5" inches (the angle of the camera makes it look a little larger, but when measured from the side it was 5 inches).If we take that with the 3" of actual clearance that we found earlier it would mean that my muffler sticks out 2" past the body line where the cross-member used to sit. Seems a lot - but so far I am quite happy I installed this because the car sounds a LOT more refined and not having had any scraping issues really so far makes for 1 happy camper!

Sunday, February 6, 2011

GTS = GT Stealth?

In the past I've made the (cheezy) pun of my GTS Badges meaning "GT Stroker".. After my most recent mod I guess now I can call it "GT Stealth" or perhaps I should get some of the Holden 'SS' badges for a GT SS / 'Stealth Stroker'. What is it you ask? It's the - at this point - infamous Patrick G Drone Killer Mod, aka the Magnaflow 12468 Muffler in the tunnel brace as discussed over here on

Back in September Patrick G had posted that people with long tube headers could install a magnaflow 12468 right in the location where the tunnel brace is to really get rid of some of the drone some people had. With my stroker build I had already switched back to Stock mufflers since the sound was basically unbearable... I guess i'm starting to get a few gray hairs here and there because loud just doesn't do anything for me.. Smooth & Quiet is the way to go  ( & it keeps the family happy!). However , even with the stock mufflers I had a metallic sound I was never happy about, and a NASTY ass rattle.

The rattle was because my exhaust was laying on the tunnel brace. Several shops that looked at it in the past could NOT do anything about this which was a little frustrating. I still think my ARH must've gotten tweaked in shipment or something since I notice other peoples systems don't seem to sit as low as mine, hence my dented cats etc and why I keep raising my car to avoid scraping issues! Pretty frustrating and I guess point of continual pain....

I've had the muffler since December 2010 and one day last week after work I swung by the local Bucky's  - yeah I know right.. Not a super 'speed shop', but I know some of the guys there and they're always very nice! Thanks again Marvin & Randy! - and they were able to get me in after I showed them some of the pictures and how it would be an easy install. At first I was thinking to keep the original pipes so I could swap back to non-muffler, but with Dyno runs by Patrick G showing there's no loss except in the 'nasty sound' department I figured what the hell and just had them stick it in. Took them about an hour roughly so it was a fairly straight forward job!

The Magnaflow 12468 Fits snuggly in the tunnel.

Bolting things up
 The drive home - wow, what a difference.. my car I swear sounded almost stock on the inside - no drone, no rattling, just humming along! From the outside it still rumbles but very refinedly so. I figured i'd give it a quick wash since I hadn't in ages. As I start hosing it down the guy over at the vacuums comes over and says "Hey is that a G8?" and starts a conversation about it. Doesn't happen often (read: at all) to me so I was pleasantly surprised!
After a quick wash - my car was FILTHY!

In the end I am REALLY happy with how it sounds right now. It still has a rumble etc, but the raspyness is gone and it seems to have a little more bass to it - in one word (ok two...) "Classy Muscle"... My only concern right now is STILL the clearance on the bottom.. I put a block under the car and put marks on it to measure how far my cats and this new muffler now sit from the ground. As you can tell from the picture it sticks out quite a bit and it turns out from either the cats or muffler I basically only have 3 measly inches for clearance...

Yeah that sticks out by quite a bit.. 1" i'd guess?
I don't know about you guys, but I'm already hearing the scraping sounds in my head unless I raise it a whole inch or so.. (which would put me back at what... stock height???... Oh well.. guess I'm getting too old for some of this stuff and when picking between lowered or stealth sound I'm going to have to give the win to stealth sound. (i've had my car practically slammed when I first got my Pedders... while it looks AWESOME , driveability & road conditions around where I live & work just make it impossible..).

In review here's a quick history of my exhaust:

Stock = Is this thing even on??
Stock + H-Pipe = Hey if I stick my head in my muffler I hear a nice rumble
Stock + H-Pipe + Axle-Backs = Nice rumble
ARH + Axle-Backs = even more rumbly (but always a little metallic)
ARH + Axle-Backs + Stroker Setup 1 = Holy crap - LOUD!
ARH + Axle-Backs + Stroker Setup 2 = Animals fleeing, Small Children crying
ARH + Stock Mufflers + Stroker Setup 2 = NOT Bad,  LOUD on startup, but very passable when warmed up - though a bit metallic still
ARH + Stock Mufflers + Stroker Setup 2 + 12468 Muffler = VERY Clean  & Deep - just about perfect!