Which is better, X pipe or H pipe?

[Injectedcutty]

Years ago, I modified my stock crossmember for duals. Last winter, I ran across a GForce on Craigslist, and replaced it. It's much better! Not sure about the jegs crosmembers, they might be ok also.

The g force member is legit....i put one on my cutlass and that thing is overbuilt! Supposedly the jegs crossmember won't work in a cutlass supreme???? Never got a good explanation as to why, but their site (jegs.com) excludes the supreme model in the applications.

 

[vanrah]

Good Morning Green87 & all;

Is it possible to run the pipes with the stock trans crossmember, or is the double hump crossmember absolutely required?

If you're looking for a cheep cross member I've got one. In 1980 when I went to duals my buddy just heated mine up & beat it with BFH! It ain't pretty but it works. If your interested I'll take any offer & you pay the shipping. It will still take a TH-350 (remove tap) as it has a tab welded on for a 700R4. Take care, Ol'e Bob.

 

[GreenRegal87]

Good Morning Green87 & all;
If you're looking for a cheep cross member I've got one. In 1980 when I went to duals my buddy just heated mine up & beat it with BFH! It ain't pretty but it works. If your interested I'll take any offer & you pay the shipping. It will still take a TH-350 (remove tap) as it has a tab welded on for a 700R4. Take care, Ol'e Bob.

What would you take for it? and how much to ship to 12901?

 

[ttype]

well... i'm not a muffler expert. as most though, have been around piles of cars. i've had piles of cars. i've had 2 sets of 3" duals. 1 was true dual with "welded" mufflers, all crush bent including 2.5" tails. if i had to describe the sound, i'd call it an 8 cylinder HD "barhopper". i like those rides as well, but they aren't for me... the drone was unbearable at cruising speed. i now have a homemade 3" x-piped dual exhaust running into 3" dynomax vt's(17957) with behind the wheel exits.(same engine) like most say, the straight dual 3" with "welded"s" would compare to an L88, whereas the 3" x-piped duals with dynmax vt and behind rear wheel exits are more like Z06. apples to oranges. they're both sweet depending on your palate. highway running is so much more comfortable with the vt's, standing beside the car with the hood open, i can hear the injectors pulsing, standing in front of the car with the welded's i couldn't hear the fan. i am waiting on new parts to come in right now. as soon as i can move the car to a good spot for recording, i ill record the symphony of sounds in several settings and share them here. i looked high and low for camparison videos, and they are few and far between. if you like Z06 style compared to L88, dynomax vt's compliment an x-pipe well..

 

[Kennybill]

About 20 years ago this was the big debate. One of the car magazines, Popular Hot Rodding, maybe, did an article about a well known Oldsmobile racer from New York city, Nick ?. At that time him and a Chicago guy were having a pissing match about who's Oldsmobile was faster. They were up Norwalk Dick Miller Oldsmobile meet for a couple years. Both cars were fast but lots of head gaskets issues back then when pushed hard. Anyhow Nick was a designer of the X pipe and with Kooks headers. His test mule was a healthy diesel blocked 1970 442 (Cutlass). The car was tricked out underneath, everything tied together. They ran the car open headers, H pipe with mufflers and X pipe with mufflers and regular pipes and mufflers. X pipe with mufflers was the fastest, open headers next, then H pipe with mufflers then regular. I noticed lots of Oldsmobiles with Nicks X pipe and mufflers next year at the Miller meet. Being a cheap *ss I always put an H pipe on everything. Nick was a good guy. I think he was an ironworker and between getting injured and building decline after 9/11 he got out of Oldsmobiles. Jmo.

 

[olds307 and 403]

With the right mufflers both sound good. The X pipe has been proven to make more power, the H makes low end torque and helps quite it down some. My 88 with 2.5" crush bent, shorty 1 5/8" headers, compact X pipe and Aerochamber mufflers sounds just plain awesome wide open and tolerable at cruise. After having an unpadded interior with 2.25" exhaust, long tube headers and glass packs, it was dam loud. I added as H pipe, helped a tiny bit, then Summit turbo mufflers, what a difference in noise.

 

[Plain Jane]

Reviving an old thread here, but I need some opinions. I'm thinking about getting a custom catback built for my 231. After a bit of research, I've decided a dual H-pipe style would be ideal for my application. Now, would the crossmember have to be modified to accept a dual exhaust, what diameter piping should I run and what would be good muffler options for me?

Car is a bone stock '86 Bonneville, looking to pick up a nice deep throaty sound and maybe a few ponies too if I could

 

[fleming442]

H's are old school tech. While functional, they don't have the scavenging properties of an X. In reality, a y-pipe would do just fine as opposed to the factory crossover pipe arrangement. I don't know if Series 2 manifolds would bolt up to the heads, but if they did, 4th gen F-bodies have a 2" primary into 3" Y.
I like the sounds of Magnaflow and Pypes straight through designs, Pypes has been getting a bad rep/rap lately with their fitment and customer service or lackthereof.

 

[lilbowtie]

Reviving an old thread here, but I need some opinions. I'm thinking about getting a custom catback built for my 231. After a bit of research, I've decided a dual H-pipe style would be ideal for my application. Now, would the crossmember have to be modified to accept a dual exhaust, what diameter piping should I run and what would be good muffler options for me?

Car is a bone stock '86 Bonneville, looking to pick up a nice deep throaty sound and maybe a few ponies too if I could

I don't understand how you plan on doing this cat back. Now if you plan on true duals w/o cat you will be spending some money. The single exhaust is enough for that engine and a dual system might even hurt performance cause you won't have any exhaust velocity for savaging. If your setting up for a later engine change go for it.

 

[Local Hero]

The previous owner had custom exhaust done from the headers back on my wagon. It has an X pipe. It was all brand new when I got it. This is the only car I've owned with either an X or an H pipe and it has been a ROYAL PAIN IN THE *ss!!!!!! And is super unnecessary for the stock 350 that feeds it.

In the 18 months I've had the car, I've had to drop the TH 400 transmission twice. I didn't want to have to take loose the exhaust because I know I would only be dealing with leaks later on. I just barely had enough room to slide the G-Force crossmember back far enough to get the trans out and back in.

Getting the driveshaft in and out is almost as tricky. It's a crapshoot between raising and lowering the rear end to make room to slide the driveshaft out the back.

When this exhaust system rots away, and I know it will due to the harsh winters we have here on the Northcoast, and this is a daily/winter beater... it will get stock manifolds back on with true duals and no X or H pipe.