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Mark-535i-sport

Exhaust options.

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At the last MOT the tester noted the system on my 535i is corroded so I have been looking at options for replacement that aren't horrifically expensive.  

 

Any suggestions and experience of their quality, sound etc please?

 

I had Eisenmann on the E30 M3 and it was lovely but not cheap.

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The one I went for is a fritz system. That a complete system including exhaust manifold. 

 

It's very nicely made but is a grand in total plus vat. I think its worth it. Its not that loud in the car but it had a note (a good one). Standing at the back of the car it is loud. 

 

I don't have experience of other systems. This is the second fritz system I have had.

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8 hours ago, Sir Anthony Regents-Park said:

New from BMW. Expensive but they are quiet, fit perfectly, perform as intended and last 15+ years. 

I think he wants a note.

 

The one good reason I can give you for not buying the fritz system is having to change the exhaust manifolds. One mine a stud broke, the in acceptable one and the engine had to come out to drill it out. However it has 12 new studs and nuts now so that all parts of the programme of renewal I am willing to undertake. If those studs have never been off then one if likely to break. If you fancy getting the engine for a good clean then why not. 

 

If you intend to keep her slowly over time everything needs to come apart and back together again.

 

Is it a manual?

Edited by bm0p700f

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Yes, it's a manual sport.

 

I'd been thinking of going with the manifold as well but I've had experience of stainless manifolds cracking before and that was no fun. 

 

Zero exhausts in Kent have quoted 1200 for a custom system and they did an awesome job on my old TWR 323is (an E21 323i but with a 240bhp M30 conversion) but they're booked till spring '22. 

 

There was a 540i Supersprint system on Face-ache the other day which I could have maybe had altered to fit? I hesitated and missed it though anyway.

 

I know OE will fit well etc but they're a bit too quiet and way too expensive.  

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The fritz system with manifold looks well made. I have had it one now for 5 months with no issues. 

 

That e21 is exactly what I would like to create. It must have been tail happy fun.

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How does it sound?  Any noticeable improvement in performance?

 

Sadly I sold the E21 before it was finished, which I regret hugely.  It was by far the rarest and most powerful period incarnation of the E21 and TWR only built 3 of them, with only 2 surviving today. Unfortunately the new owner turned it into an Alpina B6 lookalike with stripes and badges galore. The original car was far more stealth.  There's an old thread here if you're interested in seeing it? 

https://www.pistonheads.com/gassing/topic.asp?t=907138

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I think there is a small gain in power. I have not had it on a dyno though. However the old exhaust was blowing through the back box. It could be just that. 

 

It's quieter than a blowing exhaust. The note is typical bmw m30 but louder. Its not overly load in the car and there is no drone. I'd do a video but the idle note is quite different from what you here on the road and I cut video whilst driving. 

 

I fitted it because it will compliment the alpina engine copy I am having built for my e34 (260 hp hopefully). Alpina had a similar system on the b10. 

 

What you had in your e21 is a tuned m90. That made its way into the e28 alpina b9 in 1983?  You may have had an earlier version.  Of course if the cylinder bore was 92mm then you had an m30b34. The m90 had a 93.4mm bore. 

 

The m535i engine on the e12 was a m90. 93.4mm bore and 84mm crank giving 3453cc. These engines gave alot of low rpm torque. 

 

The m30b34 92mm bore and 86mm stroke did not arrive until the e28 debuted I believe. 

 

 

Edited by bm0p700f

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I had a fritz manifold and system on my e28, first thing i did performance wise on the rolling road (and it went on 3) it made as far as i could tell no difference when compared to stock versions.

 

Sounded good but in terms of power there is not much to be had with one.

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That probably true on stock tune or near stock tunes simply because one of the limit to power gain is the valve size on the b34 cylinder head. Schrick cams can't overcome that. One of the reasons you may not have seen the power gains you hoped for is the 46mm inlet valves. I don't recall the head work you had done included larger valves. Also alpina reworked the b34 cylinder head to look like the later b35 head (larger hemi chambers and revised inlet port and larger valves) the larger hemi chamber altered the amount of swirl in the inlet charge and altered the squish band for more complete combustion. Bmw did not go with the 1mm larger valves on the exhaust side for the mass production b35 head but kept the 1mm larger inlet valves. 

 

It's the inability of the b34 head to get extra air flow/ the limitations of the b34 combustion chamber to burn sufficient fuel that will.limit its power output. These are the only reason I can think of why alpina got more than you did.

 

Hense the 6 branch exhaust on a m30b35 in stock tune will probabbly not help improve power much at all but on a tuned engine at high rpm it could. 

 

The stock b35 limit to airflow and power is the camshaft and the Lower compression ratio. 

Edited by bm0p700f

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I'm afraid i just think their claims are fantasy, the head porting was done by someone with experience of M10 engines so 2/3rds the M30 and the ports are much the same.

 

They were opened out and smoothed but the discussion was it wasn't worth the bigger valves.

 

The schrick cam and porting made a difference as did the Evolve chip in the ECU, i actually had an alpina ECU but never got the chance to RR the car with it.

 

But i had an RR with FB against an stock car and figures much the same, then RR with cam and head and K&N, better, then with chip, better still.

 

Honestly i think the biggest gain would have been an AFM delete and mappable ECU  and with that i would imagine 240ish (i had 233) as the fueling curve was still off but none of that i would attribute to the exhaust.

 

Did you get a baseline figure on yours?

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 fritz can claim what they like (rich said a m30b30 can do 200+hp) as these claims are just that claims to me which I would never verify. I have not had the car with this engine on a RR.  A RR will be used with the new engine to make sure it set up right (afm spring tension). 

 

The difference in performance I noted could well be the blowing exhaust vs the new one. It could also be lower car mass. 

 

it is the sort of system that could provide a gain with more heavily modified engine ( lightly worked b35 head, high compression pistons and alpina camshaft,). one would not be able to separate the gain  from the exhaust for the gains for the other changes as they all work together and not in a summative way. 

 

Also given the manifold is stainless steel it holds less heat than the cast manifold so it less likely to cause damage to my fresh engine. The system is also be lighter (stock system is something like 33kg excluding the manifold) and the fritz system is certainly lighter. With the cast iron manifold the whole thing is over 50kg. There is a performance gain there. So even if it does nothing for power the sound , weight reduction and potential reduction in risk of  head warping is enough for me.

 

 Most of the gain you saw duncan could have been the camshaft. It's a bit hard to say now though. AFM delete should help a bit but if you have ready maxed out the air flow into the engine removing that restriction may not add more flow. What the biggest restriction is at 218hp is not the same as the biggest restriction at 233hp. 

 

It's all hard to say for certain but by itself a fritz system does do not much for power. Nor can one expect it to.  With serious mods (alpina esque) it could do something and it has the other (in)tangible benefits noted.

 

It should be added weight reduction is something I am going for. The op might want to the same. Lighter flywheel, lighter exhaust, a/c delete and lighter wheels. It all adds up on a heavy car.  That weight reduction will help make the car quicker all by itself.

Edited by bm0p700f

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My point is not so much what I did our you are doing more that the empirical data I have shows the FB set up to does nothing for power. 
 

It’s not sold saying “will only work with extensive Alpinaesque engine mods” but with claims for 15bhp if I recall. 
 

Sure it’s lighter and will transfer heat better but is that really a huge issue?
 

Back to the OPs question. I would say the sound good. The manifold makes the engine sound lazy at revs (in a good way) and it has a nice burble. 
 

Quality is decent though the rear box is not rounded in the front/ rear direction like oe and so I had issues with grounding. 
 

is it worth the money? Dubious I’d say and if I was going again I’d just go to somewhere like powerflow and have a system made. 

 

 

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I have the Fritz full system on my 535i together with high compression flat top pistons, lightened single mass e24 flywheel, Alpina cam and Alpina chip.  I haven’t done a rolling road though.  It’s a very torquey engine but no rocket ship.

Its a good system that will last decades, expensive yes, but all decent stainless steel exhausts will be expensive.

You can get a full system minus manifold for about £125 delivered from Poland.  I did that initially to get me going but I had a bent valve with that system on ( hence the upgrade to Alpina spec) so I can hardly compare.

 

the Fritz system is fairly loud at idle and continues in that vain through the Rev range.   At the top end it becomes raspy for the final 750rpm (like the e46 m3’s when they first came out), which is nice and lets people know you are “on it”.  
 

The middle box outer shell did split on me though and a large crack developed.  I have welded this up though.

trust this helps

i would recommend the system.

 

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Head warping is only an issue once a cylinder head is removed. Most people never know it has happened until the head gasket has gone.

 

If one buy performance parts on stated claims then the buyer car has to be setup just like the test car. Fritz's claim maybe true for there test car on there rollers. That is also true for any performance part. No one should buy anything for claimed gains and see them as summative. It simply does not work like that. 

 

The weight difference in the manifold is quite a bit. My judgement is there's at least 15 to 20kg saved on the complete system. It's noticeable as you can lift the parts with ease.

 

 

 

 

 

 

 

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Yes agreed and if I were to spend £2500 on the Supersprint manifolds for the m62tub44 engine that in my range I bet I would not see the claimed 15 to 20hp either. 

 

The m62tub46 engine develops 70hp more with a revised head and camshafts. The exhaust manifold is the same. 

 

The stock exhaust manifold is not the biggest restriction up to 6000 rpm. Therefore changing it does little or nothing for power. That's known.  Any gains from the manifold come past that and engine has to be able to breathe in at those rpms we never use for it to breathe out freely.

 

This is my second fritz system. I will most likey get another for a different car at some point. 

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The Fritz system and manifold does absolutely nothing to increase power and if anything the manifold causes a noticeable increase in under-bonnet temperatures which could cause a reduction in the power.

 

Alpina made their gains on the M30 engines with polishing, porting, camshafts and the ECU - specific gains from exhaust manifolds will only really come above 7,500 to 8,000 rpm, ie, a genuine race engine and not a road engine.

 

Mythbusters did a program years ago about exhaust manifolds and found absolutely no gains whatsoever on road tuned engines.

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I just tried recording the exhaust sound on a drive but the playback recorded no exhaust sound. It was there. Stupid phone. 

 

why are people so hung up on fritz power gain claims? Cannot folk put claims aside?

 

For the record (as I have found so much conflicting information about alpina engines) I have determined the following for the alpina b11 3.5, b10 3.5/1 and b6 3.5 cars. 

 

I don't believe alpina polished the inlet ports. If they did it goes against what engine builders normally do.  Polishing ports in general causes more fuel to fall out of suspension and power output falls. If alpina did polish the inlet ports it makes them an outlier as it not normally considered a useful modification. 

 

The older e28 alpina cars had cylinder head work that bmw copied for the b35 head. Think of the b35 head in the e32 and e34 as a mass produced version of the cylinder head aplina had made previously by hand from the b34 casting.

 

Alpina not only used a revised camshaft with 280/282 degree duration and over 10mm of lift and a revised ecu, they also

1) used more fatigue resistant rockers,

2) altered the combustion chamber to a hemi shape with the 65cc volume adopted for the b35 head. These where polished as far as I can tell.

3) 144mm conrods to reduce piston cylinder bore friction

4) custom pistons with a 10:1 compression ratio with crown to match the new combustion chambers squish area.

5) The alpina cylinder head had 47mm/39mm diameter valves. 

6) exhaust system although I have found no photos of it. 

7) the inlet ports on the b34 heads where modified to look they do on the b35 heads. Obviously on an e32/e34 alpina did not have to do much at all. 

 

This cylinder head was developed for the e28 based cars. Bmw stuck with 47/38mm valves for the b35 head simply because there camshaft did not pull much extra air in past 6000 rpm. 

 

As for under the bonnet temperatures there are various factors at play here. The stainless manifold has a lower mass and heat capacity than the cast iron stock manifold. That will reduce the amount of heat stored. Also the stainless manifold is reflective so will emit less heat per mm^2 of surface area than the rough dark surface on the cast manifold. 

 

The stainless manifold has a greater surface area to emit heat. As a result there does not seem to much if any change in under bonnet temperatures. 

 

Just because fritz (and other exhaust manufacturers) make some bold claims does not mean the system is poor or badly designed. Also at some point your manifold has to come off to change the manifold gaskets. 

 

 

 

 

Edited by bm0p700f

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I'm not slating just presenting the facts as i see them accrued with testing.

 

Yes they look and sound good and may well be lighter but the full system and manifold is £1200 and i have not seen a gain, that'sj ust a fact.

 

FB don't sell them saying gains in conjunction with extensive other mods only  stating "with some customers unable to believe the benefits that this product provides in terms of BHP, torque and economy."

 

I couldn't believe i gained nothing.....

 

Noted this is e28 application but they did used to give figures and there were various write ups in TBMW and Retro Cars back in the day extolling the virtues.

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11 hours ago, bm0p700f said:

 

why are people so hung up on fritz power gain claims? Cannot folk put claims aside?

 

For the record (as I have found so much conflicting information about alpina engines) I have determined the following for the alpina b11 3.5, b10 3.5/1 and b6 3.5 cars. 

 

I don't believe alpina polished the inlet ports. If they did it goes against what engine builders normally do.  Polishing ports in general causes more fuel to fall out of suspension and power output falls. If alpina did polish the inlet ports it makes them an outlier as it not normally considered a useful modification. 

 

 

The stainless manifold has a greater surface area to emit heat. As a result there does not seem to much if any change in under bonnet temperatures. 

 

Just because fritz (and other exhaust manufacturers) make some bold claims does not mean the system is poor or badly designed. Also at some point your manifold has to come off to change the manifold gaskets. 

 

 

 

 

 

I've snipped some bits out but if you're refusing to see that the polishing and porting of cylinder heads and inlet tracts have long been an aid to improve performance in N/A engines and also that there aren't heat issues with stainless steel exhaust manifolds then there is precious little anyone can ever say to change your views.

 

If you read back through the thread you were the one that bought up the subject of any gains from the Fritz system and since then people have either put their own opinions before you or asked for any evidence of those gains.

 

Just to address a couple of things you've stated, here is a link to an Alpina article which if you read it shows pictures of the room in which head porting and polishing took place and states the approximate hours it took to prepare each head for six cylinder and V8 engines up to the early 2000's before forced induction made those efforts obviously redundant...

 

https://www.thealpinaregister.com/article/2706

 

Just as in your own engine rebuild thread you have completely ignored any or all opinion that you find contrary to yours and constantly find ways to justify your views that go against a weight of actual evidence and peoples genuine experiences, which you had initially asked to hear.

 

I do wish you'd stop calling your engine rebuild an 'Alpina spec' engine as it appears to be nothing of the sort. I'm sure you will get an improved performance engine from the amount of money you are throwing at it but I suspect it will have little or nothing to do with Alpina components or methods - just call it a tuned M30 and be done.

 

Good luck in your endeavours.

 

 

 

 

Edited by sharkfan

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Thanks for the input guys.

 

In truth I never expected there would be any significant power gains and I asked out of idle curiosity really.

 

I'm not really wanting to run their manifold so realistically an alternative that works with the OE item would be preferable.  Has anyone got a link to the Polish system please? If cheap enough it might be good to have one in reserve just incase my current system throws in the towel and leave me high and dry? 

 

If I do anything to my engine it would be limited to a Schrick cam and lightened flywheel, although basic standalone for the ignition would be nice. Maybe DTA S40 Pro?  I'm happy enough with that kind of performance and if I wanted to make it a quick car I'd go S54 conversion anyway. 

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