Mod To Stock Mufflers - ZR-1 Net Registry Forums

Paddy_SP · 03-09-2014

This is my first post for some years, so please be nice to me! Anyway - my '90 ZR1 got parked for various domestic reasons (my wife got the Big C amongst other things - she's well now though). Over the last couple of weeks I've managed to clear a space in the dedicated 'smart' garage bay, and following the fitment of a new battery, fired the Z up and moved her out of the machine-shop/car storage area (it was one of 4 cars and 2 motorcycles in there) and across the yard to the new building.

She's sitting in there looking gorgeous, and I've done various things to get her roadworthy. Although she's only done just over 31,000 from new, I discovered that at some stage the left headlight must have been broken and replaced, as there were small fragments of lens glass in the well behind. That wouldn't have been a problem except for the fact that the idiot who replaced the lamp, didn't bother to fit a new cross-pin - the remains of the sheared-off one were still in the spindle. Consequently, the headlight could be pushed back and forth with little effort. Why it didn't do this before, I don't know.

After about four hours of cursing, I finally got it all sorted out - I had to machine up a new pin partly because trying to find one over here in the UK would be a non-starter, but mainly because I live miles from anywhere and I'm used to doing such things. The biggest problem by far though was that whoever was 'responsible' for designing the headlight assembly needs a good kicking. Several of the main securing screws were obscured by other parts- all it needed was for them to have been moved to one side - there's plenty of room, and it'd have been a simple job. As it was I busted a gut and several knuckles trying to strip it all apart.

Still - all that aside, I'd now like to modify the stock mufflers a little. Partly to ensure that all four outlets actually act as exhausts (I'm an engineer, and I'm funny about such things) and partly to make it sound a bit closer to a proper sports car. I've searched high and low - both on this site and elsewhere, but haven't found any reference to anyone doing this. Possibly it's because I'm using the wrong search terms, or maybe it's because picking up replacement exhausts for a ZR is an easy thing to do in other parts of the world. Releasing extra power isn't really an issue, as I live in a place where it's not hard to have the hedges scraping both sides of the car at the same time...

It would seem to me that I have two choices - a) I use a hole saw and cut out the blanking plates in the two inner pipes, or b) I remove the mufflers, cut the tops off, do whatever I have to inside, and then TIG-weld them back on again.

I would therefore be most grateful to hear from anyone who has any constructive comment on this!

03-09-2014	#1
Paddy_SP Join Date: Aug 2007 Location: SW England Posts: 22	Mod To Stock Mufflers This is my first post for some years, so please be nice to me! Anyway - my '90 ZR1 got parked for various domestic reasons (my wife got the Big C amongst other things - she's well now though). Over the last couple of weeks I've managed to clear a space in the dedicated 'smart' garage bay, and following the fitment of a new battery, fired the Z up and moved her out of the machine-shop/car storage area (it was one of 4 cars and 2 motorcycles in there) and across the yard to the new building. She's sitting in there looking gorgeous, and I've done various things to get her roadworthy. Although she's only done just over 31,000 from new, I discovered that at some stage the left headlight must have been broken and replaced, as there were small fragments of lens glass in the well behind. That wouldn't have been a problem except for the fact that the idiot who replaced the lamp, didn't bother to fit a new cross-pin - the remains of the sheared-off one were still in the spindle. Consequently, the headlight could be pushed back and forth with little effort. Why it didn't do this before, I don't know. After about four hours of cursing, I finally got it all sorted out - I had to machine up a new pin partly because trying to find one over here in the UK would be a non-starter, but mainly because I live miles from anywhere and I'm used to doing such things. The biggest problem by far though was that whoever was 'responsible' for designing the headlight assembly needs a good kicking. Several of the main securing screws were obscured by other parts- all it needed was for them to have been moved to one side - there's plenty of room, and it'd have been a simple job. As it was I busted a gut and several knuckles trying to strip it all apart. Still - all that aside, I'd now like to modify the stock mufflers a little. Partly to ensure that all four outlets actually act as exhausts (I'm an engineer, and I'm funny about such things) and partly to make it sound a bit closer to a proper sports car. I've searched high and low - both on this site and elsewhere, but haven't found any reference to anyone doing this. Possibly it's because I'm using the wrong search terms, or maybe it's because picking up replacement exhausts for a ZR is an easy thing to do in other parts of the world. Releasing extra power isn't really an issue, as I live in a place where it's not hard to have the hedges scraping both sides of the car at the same time... It would seem to me that I have two choices - a) I use a hole saw and cut out the blanking plates in the two inner pipes, or b) I remove the mufflers, cut the tops off, do whatever I have to inside, and then TIG-weld them back on again. I would therefore be most grateful to hear from anyone who has any constructive comment on this!