Exhaust gasses in Cabin-cough, cough, cough splutter. bleurgh :-(
- Thread starter Andrew
- Start date
Chuffer
CCCUK Member
Probably because the heater fan is sucking contaminated air into the cabin rather than just free flow of air through various gaps and cable holes etc from engine bay .
Mr. Cricket
Committee Member
Roscobbc
Moderator
Later C3's with 'turn-down' exhaust tips exiting just short of the rear bumber are an interesting 'development', especially if the car is a big block with 'rumpity-rumpity' old school cam. Best make sure you arrive at any venue with loose gravelled/singled surface before the 'cammed' Vette arrives, (and never park near or follow the car when leaving the venue). The combination of downward facing exhausts and cam will blow dust, shingle and chippings all over the place (and your own car if following!)
CaptainK
CCCUK Member
I have it on my wedding video where the photographer parked next to my C3 during the ceremony. Afterwards we had photos & videos of wife and I getting into the C3 and driving off. The video is funny as the car park is dusty / leafy and on startup my C3's sidepipes just cover the photographer's car with dust and dirt. You can hear him commenting on the video about it. Thankfully he's a mate, so I just laughed at him as I drove off. 
Extra amusingly, the videographer at the time decided to start off filming the other side's sidepipes. Probably to try and catch the sound at startup. BUT they soon changed their mind and moved away before I started up. They still got a slight covering of dust, but could have been much worse.
Extra amusingly, the videographer at the time decided to start off filming the other side's sidepipes. Probably to try and catch the sound at startup. BUT they soon changed their mind and moved away before I started up. They still got a slight covering of dust, but could have been much worse.
Roscobbc
Moderator
Many moons ago when I owned a rare 7 litre Galaxie coupe.........it was fitted with a 'silly' cam and the old school Thrush glass pack mufflers. Gutless below 1500 rpm - 2500 rpm and all hell would break out. Got stopped by a 'rookie' cop for excessive noise. Whilst it was idling he was standing behind it in shirt-sleeves trying to figure it all out........it was really amusing to see his shirt and trousers blowing all over the place (due to the exhaust pulses from the twin 3" diameter tailpipes) - truth was the exhaust wasn't excessively noisy at idle although when visting my then girlfriend (now wife) at her Victorian terrace house in East London she (and the neighbours) would always 'feel' (not hear) the car coming from up the road with window frame, crockery and ornaments vibrating around once outside (due to the extreme resonance created by the 'silly' cam). The young copper really was out of his depth, he didn't understand anything other than it had a 7 litre engine and reluctantly sent me on my way............
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Mr. Cricket
Committee Member
When I had the Cherry Bombs on the '71 it was very loud. Two conversations stand out. The first was a dog walker passing my gate as I was putting the Corvette away after a Sunday trip out. Ahh so this is where the Corvettes live he said, you woke me up this morning at 7 windows and bed shaking! Hmm sorry I said. No it was the best wake up call I've ever had mate
The other took be by surprise. Waiting at lights to turn right on a red hot day, window down, arm resting on the door a young purple haired lady pulled up on my left level with me. Gosh she said visibly shaking I need to go sit on a towel now
I did go back to stock and miss them sometimes but the others are plenty loud
The other took be by surprise. Waiting at lights to turn right on a red hot day, window down, arm resting on the door a young purple haired lady pulled up on my left level with me. Gosh she said visibly shaking I need to go sit on a towel now
I did go back to stock and miss them sometimes but the others are plenty loud
Chuffer
CCCUK Member
Nothing like spreading a little joy is there ?When I had the Cherry Bombs on the '71 it was very loud. Two conversations stand out. The first was a dog walker passing my gate as I was putting the Corvette away after a Sunday trip out. Ahh so this is where the Corvettes live he said, you woke me up this morning at 7 windows and bed shaking! Hmm sorry I said. No it was the best wake up call I've ever had mate
The other took be by surprise. Waiting at lights to turn right on a red hot day, window down, arm resting on the door a young purple haired lady pulled up on my left level with me. Gosh she said visibly shaking I need to go sit on a towel now
I did go back to stock and miss them sometimes but the others are plenty loud
My neighbour usually comes out into his drive before I have even pulled up on our drive when ever I bring the Vette home . He loves the sound emitted from the Supertrapps and sniffs the aroma of high octane fuel wafting up from the carbs !!!
teamzr1
Supporting vendor
When I designed the exhaust system for my 1999 C5 in 2009 I used these, and they still are about the same Dba level now
Roscobbc
Moderator
These were the real business back in the day. Various tube diameters. Two lengths, short case ('kin loud) - long case (not quite so loud). Packing may have been steel wool, perhaps glass fibre. They had clever system called 'Turn 'O' Lock' or something similar where the end plates were convex. The ideal being that if you needed the inlet or outlet stub to be at as slight angle to help line the pipes and muffler up you could insert a short lengthof exhaust pipe in either (or both) stubs and lever it over a few degrees. The convex end plate would effective 'lock' and permanently 'set' the stubs at the required angles.......great bit of kit!
Roscobbc
Moderator
There are several things you need to consider.
A. Length of bolt in relation to depth of tapped hole in bolt (could bottom-out in the cylinder head) - bolts can make fitting headers far easier than using studs.
Avoid using bolts too short - risk of stripping thread/vibrating loose
B. Access with ring/open ender spanner/socket on even these reduced head bolts can be challenging - consider 12 point headed bolt (if you have 12 point socket set)
C. Consider use of flat washers, perhaps spring washers.
D. Always use copper grease on threads to 'ease' future removal of bolts, especially if using ally heads.
E. Choose header gaskets carefully - carbon inpregnated core ones tend to break-up and leak. Solid copper gaskets are good and can be annealed and re-used. Over the years I've found the best gaskets so far seem to be multi-layer aluminium header gaskets - they seem to seal far better than alternative and can be re-used.
A. Length of bolt in relation to depth of tapped hole in bolt (could bottom-out in the cylinder head) - bolts can make fitting headers far easier than using studs.
Avoid using bolts too short - risk of stripping thread/vibrating loose
B. Access with ring/open ender spanner/socket on even these reduced head bolts can be challenging - consider 12 point headed bolt (if you have 12 point socket set)
C. Consider use of flat washers, perhaps spring washers.
D. Always use copper grease on threads to 'ease' future removal of bolts, especially if using ally heads.
E. Choose header gaskets carefully - carbon inpregnated core ones tend to break-up and leak. Solid copper gaskets are good and can be annealed and re-used. Over the years I've found the best gaskets so far seem to be multi-layer aluminium header gaskets - they seem to seal far better than alternative and can be re-used.
teamzr1
Supporting vendor
One other point is assuring the flange exhaust manifold gasket has the correct shape of the exhaust ports of heads
I have found command of a badly running engine where the port opening are vertical rectangular
where gasket ports are round
This causes leaks at the 12 and 6 o'clock positions and owners cannot figure what is causing poor running engine
I have found command of a badly running engine where the port opening are vertical rectangular
where gasket ports are round
This causes leaks at the 12 and 6 o'clock positions and owners cannot figure what is causing poor running engine