Going to make an X-pipe exhaust

[Howard Jones]

Went looking for the original exhaust systems as run on the race cars. I found these. Then the others seam to be trying to keep collector length correct. The problem is obviously packaging verse esthetics. The fast and easy way is usually a two in and two out single muffler or two single round mufflers, your choice.

As far as low end power goes, 400Hp in these cars will spin the tires at will in 1st and 2nd gear in slow corners. The BEST advise I can give you is to install a Quaife TBD as well as the best tires you can find if you are worried about low speed performance. Maximum torque from a perfect exhaust system will not help you if the tires can't stop spinning.

 

[mark b.]

You guys might find this interesting.

Tuned exhaust questions • Speed Talk

 

[Keith]

Went looking for the original exhaust systems as run on the race cars. I found these. Then the others seam to be trying to keep collector length correct. The problem is obviously packaging verse esthetics. The fast and easy way is usually a two in and two out single muffler or two single round mufflers, your choice.

As far as low end power goes, 400Hp in these cars will spin the tires at will in 1st and 2nd gear in slow corners. The BEST advise I can give you is to install a Quaife TBD as well as the best tires you can find if you are worried about low speed performance. Maximum torque from a perfect exhaust system will not help you if the tires can't stop spinning.

Interesting finds Howard. That's a bit of a risky set up in pic 1 though isn't it? Scavenging directly from header to rocker cover without a Reed valve would be asking for a catastrophic backfire calamity!

 

[Darrin]

....The BEST advise I can give you is to install a Quaife TBD as well as the best tires you can find if you are worried about low speed performance. Maximum torque from a perfect exhaust system will not help you if the tires can't stop spinning.

I'm running a limited slip with 305 Nitto NT01 tires. They should hook up very well, but I understand what you are saying.

 

[Howard Jones]

Ya, Col, I was wondering what the hell that was. It has to be something like this.............right?


Vibrant Performance E-VAC Scavenger Kits 1189 - Free Shipping on Orders Over $99 at Summit Racing

 

[Ron McCall]

How about this?

 

[Darrin]

How about this?

I'm thinking, based on the tests I have seen, it would be best if the X-pipe was placed further down allowing the collector to be extended. This MIGHT be OK as is, but none of the tests I saw used this configuration. It was always lengthening the collector before any bends.

Note that the collector need not be over 18" it seems. For whatever reason, that length tended to be the magic number although anything over 9" or so seemed to work fairly well. One thing I noted was that there was no downside at any RPM range for running a collector so it was all gain.