Hi, Rabin

I've been to your site in my searches for PRV performance. Thanks for joining up and thanks for your comments - it means a lot!

The engine has been quite fulfilling, and one can't expect miracles from 2.8 litres, especially when it's hauling around 3300 lbs of steel and sound deadening. The noise it makes (when the headers aren't barking) isn't exactly exciting but with the weak B280F cams I certainly don't expect it to sound like anything more than a delivery van.

The engine really ISN'T the problem in this car, to be perfectly honest. I've actually measured up the engine bay of my GT to see if it would fit - no hope, but that's probably a good thing. I had my doubts at first, thinking of about 100 other options that would surely deliver more power but I'm glad I stuck with the PRV because I now appreciate how good of an engine it is. Or how good it CAN be...

The problem is that the car doesn't move me. It's the most exciting 700/900 series chassis, at least it is to me, but I just can't bring myself to do anything with it. I can't really decide what kind of person will end up with this car but I suspect it will be someone who wants a 780, not someone who wants a half-finished performance car wannabe project. That's why I'm returning it to a more-or-less stock state.

Again with the compromises: I made the headers long and small diameter to maximise torque and scavenging, but I now believe that the tiny camshaft (especially on the exhaust side) isn't taking advantage of the scavenging properties. I don't anticipate much loss from the manifolds, aside from a lack of noise that is.

I will respond more when I get the chance to, and I will certainly report back on the difference in manifolds from the headers.

Well - I'm glad the engine itself isn't the issue.

20+ years ago the stock engine in my >2800lb beater 504 w/4-sp manual was quite quick and it would easily see off E28 528's on the highway no prob. The Aussiefrogs site has a really nice following for the PRV - but they all seam to like the odd fire and most all the build ups I've read there are with larger pistons and sleeves on the odd fire crank. The sound of a odd fire at full chat makes your spine tingle. (I've heard descriptions like "unholy howl" to describe it) The even fire I only spent a little time with before parting the car (it was t-boned total loss that I bought) - and while it was silky smooth it and sounded OK- there was no spine tingles...

I'll likely mostly leave the 30T engine stock and just reseal it, rebuild the Weber and call it done for now. A better build up on the "parts" short block might follow later if I really like it. My 504 currently has all the suspension and brakes off of an 86' 505 turbo. The carb'd euro 2.0L engine in it is sweet as can be - but simply underpowered. When did my road race school in it (insert laughter here) I got a lot of funny looks and the odd laugh until we hit the track. They didn't think they had a car slow enough to pair me with for passing, but after the late 90's Sentra COULDN'T pass me they put me against a hopped up mini with a 1275cc engine and we diced it up nice. (Except when the driver of the mini drove off the track when I passed him on the inside and he stared to long - he later admitted it was in disbelief...

I understand your point about a car not getting the emotional attachment going (Subaru's for me). I have the reverse affliction with my Peugeot's. They've got terrible resale, no one knows what the hell they are, I get ridiculed by friends and family - but I love the damn things and have no issue throwing money and devising crazy ideas to develop them into what I want them to be. Two little kids, home renos, etc etc etc make it all a LONG ass build time, but half the fun and what keeps me sane is researching the options to that when I can make stuff happen - I know exactly what I want. I've owned a Peugeot since I was ~17, turned 40 this year and the cars still impress the hell out of me. Simply can't find anything that comes close for the $$ spent.

If you're feeling particularly adventureous, and really want to push the "eclectic car" owner envelope - I highly recommend you take a "newer" 505 for a rip. There's actually a cheap 505 STX on kijiji in Calgary for cheap ($1200 not running and likely go for MUCH cheaper), along with a minty one for $8500... Both sadly auto - but super easy to swap to manual if you have the parts. I could bet you money that you will have never sat in a more comfortable car. Those crazy French know how to build seats, steering, and compliant suspensions that just plain work awesome. Even my '00 V70R can't touch it for road holding, comfort, and steering perfection. It will however blow the doors off any of my Peugeot's in a straight line... for now anyway.

BTW: Please keep me in mind for the headers you built. I'd hate to see them tossed or cut up if they'd work with some mods on my 504.

Rabin

Well there's no way the headers will get cut or tossed, and I have no clue what else they'd fit. I had to jog the driver side downpipe pretty hard because the outlet of the manifold pointed RIGHT AT the steering shaft, so if the Peugeot shaft goes between the downpipe and the engine, these headers probably won't fit.

They're leaning up against the wall of the garage, BTW...

This weekend I installed the manifolds and built up the downpipes, and left everything else alone. Driving impressions tell me that the bottom half of the tachometer is a bit down on torque, maybe even a lot at times, but I'd be tempted to say that the manifolds and 2" downpipes flow just about as well as the headers in the top end.

Where the exhaust note was smooth and featureless, it is now a bit burbly - think Subaru. It is MUCH quieter - quiet enough now to discover a nasty exhaust leak that seems to be the source of much of the objectionable noise I had before!!! Crap. I'll have to deal with that later. I had no idea that the flatulance between 2300 & 2800 RPM was from the midpipe. It's quieter than it was, so I know the headers were making it worse, but still.

Power impressions can't be trusted, though: it's been a week since I've driven it (been driving the slow & comfy truck) and there was only a couple days before that with the car on the (1" taller) winter tires, plus with it being so much quieter it will naturally feel different.

So mixed feelings: it's quieter and sounds more interesting, but it's not as snappy and I should have been able to deal with what was really bugging me without yanking the headers. Oh well, when I deal with the leak it'll be nice and quiet.

I studied your header build and sadly the engine in the Volvo looks like it sits pretty far in front of the firewall. The PRV when in the 504 is pretty much right against the firewall - so there's no way it'll work for me. In the 505 the HVAC system is behind the motor separated by a molded foam panel - so it won't work in that either...

Only application I can think of where it would work is my pipe dream locost built with a PRV 5-sp and IRS.

Thanks very much for the run down on the differences. I quite expected it to be a pit peppier down low and suffer up high... Interesting to hear it was the opposite. Your exhaust velocity and scavenging is working pretty darn well if that's the case... Sucks about the source of the sound, but at least you'll have it figured out.

May I ask why you didn't do a H or X pipe to connect the two sides together?

Rabin

No room to run duals in a 700 with IRS. There's barely room for a single 3"! I built my own merge but it cracked, I guess. I braced it a little and I thought it was enough, guess not.

And yeah, most of the engine sits in front of the front wheels, and the firewall in a 700 is a bit further back than in a 200. It leaves lots of room for pipes behind the engine but they've got a few things to get past first.

In case you missed any of my tirades on headers...

Most headers that you can buy from the aftermarket nowadays would perform just as you suggested. The tubes are way too big for decent scavenging and are designed for flow (and ego) only. They're also never "tuned", the tubes are all just random lengths, so each cylinder is "tuned" for a different resonance (RPM). This makes each cylinder operate more efficiently at different RPMs - or it WOULD if the tube diameters were properly sized - though all engine managements tend to average the airflow information and meter the fuel proportionately between all the cylinders. When one cylinder breathes more air it gets more fuel, but only by a little bit, while all the other cylinders get more fuel by default when they don't need it.

The headers I designed and built were sized using a program called PipeMax and backed up by an information pack I purchased from Headers By Ed. PipeMax said that the ID should be between 1.2 and 1.4" and based on the camshaft measurements I made and the predicted RPM peak, the tubes should be about 33.5" long, with a suggested collector size of 2". HBE said that 1 3/8" OD tubes were not restrictive to about 180-190 hp on a 6 cylinder, and I should use between a 1 7/8" to a 2 1/8" collector. HBE also says that if in doubt, go smaller on the tubes, plus you should consider altitude and intended use in your diameter selection.

I used 1 3/8" (nominally) 18 gauge tubing. The diameter is a little bit over 1.4" OD, so the ID is right in the range of where Pipe Max suggested, and close enough to HBE. I made a 2" collector, deferring to the "safe" choice by HBE and the suggested diameter from PipeMax. I did design them to 33 1/2" but they vary 1/4" or so each way, which is far closer than the 5-6" range I've seen on some aftermarket headers.

So yeah, I did kind of mean for them to operate in the low RPM to midrange area, and I did mean for them to scavenge. That means they're going to bark loudly, and they'll all bark at one narrow RPM range. The 18 gauge tubing also means that they're very flexible and they don't absorb too much noise, unfortunately, so yeah they're going to be noisy...

As a fix for the noise I could brace them up a bit and see if I can get the tubes to stop rattling, and with the midpipe leak/resonance fixed up I MAY re-install them this winter, just to put the final nail in the coffin or to see if I can live with them. That will mean sacrificing whatever ceramic coating is left from scraping them up getting them in and out and in and out and in the car again...

Holy smokes - yup - I missed the tirade on the headers, so now I'm even more impressed with them... And even SADDER that they can't work on my car!

Too bad they were already coated, as I was going to suggest splitting some heavier gauge tubing and encasing some of the straight sections of the primaries just to change the frequency they're ringing at. That and maybe banding them together at points where possible to again change the resonance.

The data you just provided me though regarding the header design is pure gold - Thanks very much for that. May I ask where you sourced the tubing and such? I'd eventually love to build the same set up specifically for my 504. (Unless you start doing custom work on the side for others?)

Rabin

The 505 STX the engine is either right over the front tires or slightly behind it. Most don't even know - but the balance is 51/49 front to rear, and the car is exceptionally well balanced.

There's room to go down and out just behind the cross member without fouling to much at all. They're a rear steer rack, so it's quite a bit more out of the way I think.

If you get a chance to do pictures of the Renault manifolds, I'd love to see how you did the downpipes on a RWD car.

Rabin

http://www.greatplainsas.com/scexhaustparts.html

That's where I got the elbows & straight pipes from. Prices were good, shipping was reasonable, but as you probably saw I had to make my own collectors. I'm not sure I'd do 18 gauge again as it's mighty thin around the outside of the bend, and takes a more delicate touch than I tend to practice in order to weld them together. It's not impossible but the burn-throughs happen suddenly. The 18 gauge doesn't contain the sound, so no matter HOW you manage the resonance you're still going to get noise through the wall of the tubes.

Coated or not, I may tackle some sort of stiffening attempts. The tubes are pretty spread out so banding them is going to look silly, so I'm trying to cook something else up. I was thinking along the lines of a half of a 1.5" pipe as a reinforcing pad and then *something* that'll bind them together. There might only be a need at the one spot where the two tubes may have been dinging together, as I tried clamping tubes on the other header but got nothing even close to the noise reduction that I got from the first one. Or I may leave that for the next owner of the headers to figure out.

I'll try snapping a couple of photos of the downpipes next time I get a chance. It may not be until the winter when I bring the car back into the garage to dick around with. The DS has a fairly radical and sudden S bend to it immediately following the flange, to avoid the steering shaft, and other than that they're pretty straightforward.

And sorry, no time for customer work on the side!

Could you "band" them on the inside of the tubes - does this make sense. Could you find some way to bridge between pipes on the inside of the bends. This way you won't see the welds. Just a thought.

Anything to hide my welds is a good thought, Craig!

I really don't know what would be a good thing here. Headers typically just have a band around the tubes, after the last bends and just before the collector. This way the tubes are all stiffened where their growth will be parallel and equal. You don't normally see tubes tied together mid-stream, so I'm hesitant to actually tie them together since they'll all be growing in different directions. Granted, things are quite flexible with all the 3D bends and the small diameter, thinwall tubes, but I'd rather not tempt fate.

I think if I do anything I'll do that band just in front of the collectors, and if I get really crazy I'd just do a small diameter roundbar wrap around the tubes midway up so that they're just stiffened but not really restrained. A little bit of silver high-temp paint and things should be fine. I know how to make them STIFF, I need to figure out how to keep them flexible but to keep them from vibrating, while keeping the stiffening device from breaking.

We'll talk on Saturday...my idea isn't any different physically. My Stahl has the band that you're talking about. Anyway - no worries, we'll figure something out.

Hey all,

Long time no update. Not much happening to the car this year. I plan on driving it and enjoying it much more than last year, instead of working on it. It should be on the road before May.

I had a wicked leak down where the two 2" pipes joined up to make a 3" pipe, creating a bunch of noise and probably drawing in lots of nice fresh air to confuse the O2 sensor. I hope, anyway, 'cause the fuel economy didn't please me. It was such a gradual merge that I had to box the whole thing - pictures to follow. I am not putting the headers back in just yet - I'll live with the exhaust the way it is and see how it feels. It’s got a nice burble down low and above 3500 it’s quiet, but right in that 2000-2750 range it’s still a bit raspy. If I could get rid of that I’d be a happy boy – maybe a small pair of resonators in the downpipes, but installed in such a way that I can modify the headers to use them too, should I reinstall those.

I also had a lot of contamination around the tailpipe, from using a flap wheel and a belt sander on the stainless that I'd previously used on carbon steel. Don't do this, kiddies. The stainless will then bloom rust like crazy. I got a bunch of pristine new flap wheel and scotchbrite discs and a nice new stainless wire wheel & brush, and buffed the heck out of the pipe. Against Craig's advice, I did put a bit of a shine to it. Yes it'll be wasted time because yes, the whole thing will turn goldy-brown with heat & oxidization (like the rest of my exhaust did) but at least it won't be rusty. I don't mind the patina.

I did a bit of maintenance too - the valves were clattering a bit more than I liked so I adjusted them again. The intakes I set to .006" and the exhausts to .010" - intakes are at the wide spec and the exhausts are at the narrow spec setting. I noticed that one pair of valves were really hard to set - if I set the intake on the rear of the right bank with the intake lobe 180* away from the rocker, and then if I checked it with the exhaust lobe lifting the valve, the intake clearance was now about .002" wider than it was when I set it. I could get a similar result by prying the cam over in its bores. I set that valve to .005”, just because.

The big deal this year is the install of the air conditioning. I'm using a compressor sourced from Dale's red car - it seems to be in reasonable shape, and makes a nice "poop" sound when turned over by hand. I cleaned it up and gave it a light buff, and painted the rest of the bolt-on stuff. As I was using the EP valve covers I needed to make a special bracket to mount the Volvo AC compressor. The EP uses a serpentine pulley and since I was using the Volvo’s v-belts, I needed some sort of adjuster. I didn’t want to do an idler pulley but I still might. I’m not 100% happy with this bracket, so we’ll see how things go.

I’m using Dura-Cool products throughout. I spoke with a tech at Cool Earth Inc about it all and he gave me some really good advice about the installation & preparation of this system. If you believe the literature, their stuff works miracles. I have a brand new dryer/receiver from FCP and a new R12 orifice, plus all the o-rings and fittings from an R12->R134 retrofit kit. The rest of the system is R12. The compressor has been drained but not flushed out – it’s not important to get ALL of the old oil out of the system when installing Dura-Cool. I will be cleaning out the hoses and exchangers with Brakleen, as recommended by Cool Earth. Brakleen is a hydrocarbon so it’s totally safe in the hydrocarbon-based Dura-Cool system. I’m looking forward to this… It should outperform the R12 system and it should blow away an R134 retrofit, plus it sucks less power from the engine and is safer for the environment.

Otherwise, not much is going on with the car. I can’t wait to get into it and start enjoying it!

Excellent to hear you still have it... I was beginning to worry you sold it off...

WRT to the raspy exhaust - Do you think if you replaced the merge with a small 2 in - 1 out muffler / resonator that would help, or run the "Y" direct into a single resonator (if you have room that is)? The 505 V6 has the "Y" join and immediately goes into the converter. I'd guess any resonance would be nipped at the start of that big single tube.

I'm also very interested in your AC project - I've got a couple cars that I want to restore, and functioning AC is high on the list.

Rabin

You won't need AC for a little cruise this weekend or next!;-)

I really hope you can get this car to a point you're happy with it for a few years!