I have a 65 Mustang, original 289 & transmission. I am now running traditional dual exhaust with Flowmasters. Nice sound but I now want to add two Granatelli electronic exhaust cut-outs. Whereas I am tearing out the entire exhaust I would like to get advise/opinions on what type of mufflers to install to have a quiet tone (low rumble) with the cut outs closed. I am doing this changeover to keep the neighbors and wife happy but to get the open sound on the road. If anyone has installed dual cutouts, what exhaust would you recommend and I would appreciate and advise you could pass on.
Thanks I appreciate your time and advise.
I've seen a lot of complaints about various exhaust cutouts in the past. I don't know if they apply to Granatelli or not. Consensus seemed to be that QTP were the best out there when I was doing the digging. I put them on my car and have been very happy. I'm just suggesting you look into your Granatelli's before you take the plunge.
Regarding mufflers, a lot of guys will say that Super Turbos will do the trick for you. I had them on a dual 2.5" system and they were indeed VERY quiet. However, they're not doing enough for my taste on my dual 3" system. So, I'm looking for a stock muffler to put on, next. I want a very docile car until I open the cutout.
FastDriver, can I conclude from your reply that you recommend a stock set of mufflers, or a set of Super Turbos with a pair of QTP cutouts. I will be ordering this week an just want to be sure I have it right.
Well, you didn't mention the size of your exhaust. If you're running a 2.5" system, then I think you'll be happy with the Super Turbos. There are different sizes available. So make sure you use the biggest muffler that will fit in the muffler area under your car. Yes, full recommendation on the QTP cutouts.
Not sure what size exhaust you are running...but if you want a quiet exhaust...choose a muffler from a FACTORY application in the appropriate size...after all, you are running cutouts...why in the world would you chose something that is going to be louder than stock? Chances are your cutouts are going to leak and increase volume anyway...they often do.
My QTPs don't leak, but I've only had 'em for 2 years. I've heard that others will leak straight out of the gate. Also, I think a lot of people prefer the sound of different mufflers, and their goal may not be to totally eliminate that nice rumble. And, it's not just about volume to some. That's why people prefer Corsa vs. Borla vs. Flowmaster, etc... X's vs. H's, etc... They all have their own unique note.
True enough...but mufflers like Flowmaster 40s/50s, and Super Turbos are NOT quiet mufflers...that was my point...it defeats the hole point of the exercise if to OP chooses a muffler that the wife thinks is loud....besides, there are plenty of nice sounding stock application mufflers...vintage mustangs have a good amount of room to work with, so must v8 mufflers will fit without issue.