PontiacBonnevilleClub.com

Hello, been a lurker for quite some time but never registered. I have been into gtp’s for over thirteen years on and off but owning a Bonneville is new to me. I recently purchased an 02 Bonneville SSEI with only 115k on the odometer, I picked it up for only $1400 because the original owner thought it had a busted head gasket when really it was only the plastic coolant elbow. The original owner had performed a number of mods like ZZP 3.4 pulley, cam swap and springs, intense pcm and a set of high flow flomasters which really sound awful.

I have fixed the coolant elbows with the aluminum ones and flushed the heater core and coolant system and filled it with 50/50 green mix, did an oil change using Pennzoil platinum oil, I have all new ngk tr6 plugs for it, got a set of speed daddy headers in which I will be fully modifying and making them equal length and surfacing them. I also went ahead and got an intense fwi kit, hooker aerochamber one in duals out muffler and a ZZP resonator.

I have a lot more planned for this car and will make sure to keep the forum updated as I fix, replace and modify it.

Welcome. Thats a steal for what you got.

The header rework is probably not be worth it at the original primary length. Longtubes 30-35" would actually allow for scavenging and harmonic gains.

Thanks, yeah I thought so too. As for the headers I understand what your saying but I am not modifying the primary tubes, I am not even modifying the collector ether. The front header wraps around and goes to a cross over then into the rear down pipe. I am going to run that cross over down and underneath of the car. I am then going to run the rear down pipe under then run it in a big loop to equal the length of the front pipe. I have done this on a few gtp’s and it works beautifully. It actually makes the car sound like a gtr.

Now I got ya. I agree, equal length secondaries actually make 3800s sound decent.

Yeah I should of worded that better. But absolutely, 3800’s with equal length (secondaries) sound absolutely amazing and if more 3800 owners heard it up close they would understand why it’s worth the extra work.

I see that you have a RD250, I just got done restoring a 73 rd250, still waiting on the new seat which was $450 and still have to paint the tins, but it’s a quick ride for a 250. Have a set of 350 cylinders for it as well.

RDs are a lot of fun.

Mine is a DS7, just before the R5 and DS7 were updated and rebranded as RD350/250 respectively. I swapped in the 74 RD250 drivetrain but kept the DS7 clutch/generator covers. The DS7 didn't have reed valves like the RDs and that's the only easy way to tell it's swapped. I tried a high comp/quench ported 350 top end but failed on getting it tuned correctly twice which melted pistons. It was accidental power wheelie city.. I ended up just staying with the RD250 top end because I can literally beat the crap out of it all day and it loves me for it. It still lifts the front tire and will get up over 100mph. Here are some pics.

Welcome to the forums!

I love seeing videos of the RWD Aussie 3800s, and they sound very pleasant. Haven't seen many people go to the trouble of doing true dual equal length headers on the FWD stuff. I believe there's a guy with a Grand Prix somewhere on Youtube doing it.

I think the first time I heard it was in a equal primary and secondary format in a Fiero. It basically sounded fake it was that good.

@nos4blood70 Thanks bud and I’m glad to be apart of the forum. Those Australian 3800’s sounds quite wicked. They do run true duals and have a very unique sound because of that.

@95naSTA absolutely, on my old gtp every time someone heard it they instantly said gtr, on my old gtp I had done hours and hours of research in flow rate and turbulence in the fwd 3800 design to figure out why they were so blah on the exhaust note, I have made hundreds of custom exhaust systems for Yamaha SXS and twostroke Yamaha banshees but this car gave me a run around. I had tried at least twelve different variations from true duals, larger diameter piping, multiple resonators and exhausts. At the end I landed on the equal length secondary into a two to one collector, then into a resonator then into a single into dual aerochamber muffler. I had tried the dual one into one aerochamber but it was way to noisy up top and had a very high pitch noise. With the single it has a very low squeal to it and when revved has a slight pop to it.