Mercedes-Benz Forum banner

101 - 110 of 110 Posts

·
Premium Member
Joined
·
4,175 Posts
Discussion Starter #101
I’ve got to say that all the speculation on the benefit of each part sure makes me think, “If you really want to end up with some solid gains from your motor, just send the car to Carobu to let them do it right.” They’ve already proven that another shop doesn’t give customers a good return on their dollar.

I feel that regular maintenance and repeatable jobs make sense for us to do on our own, but I believe that the experience that Carobu has now will probably make their labor much more efficient at getting the job done.

I feel it’s too bad that we haven’t seen a gen1 motor with the smaller valves go through this ringer yet. The 560 and gen2 500 supposedly have larger valves (and ports), at least the exhaust valves. Right?


Sent from my iPhone using Tapatalk
Gen2 500 have 560 heads bolted on

Gen1 heads have same spec exhaust valves as gen2
Gen1 intake valves 44.2mm
Gen2 intake valves 46.2mm

When AMG were working the Gen1 heads before the Gen2 was launched they were basically swapping in 46.2mm intake valves (and new seats to match) and the valves worked and also back-cut to increase flow.

AMG ported the gen1 heads - aka- ported intake bowl to match the larger seats and cleaned up the ports of casting dags/sharp edges etc and tweeked the short radius turn and valve guide/area - the main improvement was in port-matching the heads to the gasket and port matching the intake and port matching the exhaust ports - the usual thing you do when porting matching.
They did tweek the Gen1 intake intake runners and the openings to the plenum chamber.
This was required to match the cams AMG were swapping in.

When MB saw what AMG did they basically copied AMG to release the Gen2 heads and Gen2 intake.
The later version of the Gen1 engine has plenty of torque so the heads were adequate for that engine build and cam

When MB released the Gen2 500 they also swapped cams accordingly (dependant on comp ratio & required emissions of where the car was being exported to)

The 560 heads flow well - they just need the usual tidy up when the heads are being re-furbed but the most important item is port-matching the heads to the gasket and the intake to the gasket so it is all a smooth air-flow minimising turbulence. And same for exhaust ports.

It is still the intake plenum design which lets lets it all down
 

·
Premium Member
Joined
·
4,175 Posts
Discussion Starter #103 (Edited)
They have finished phase 1 of the dyno testing (around 100 pulls on the dyno so far)
Pulled the engine down to inspect
Rod bearings fine /crank fine / piston/rings /cylinder walls fine - all good considering the beating the used engine has had (only work - heads were re-freshed as valve guides already worn from previous mileage)

So next phase-
Custom forged 98.5mm pistons on order (max they can go with standard head-gaskets) and these will match the factory rod pins - so keeping the MB rods
Comp ratio will be bumped up to 10.5:1
Standard pistons are 96.50mm so 2mm gain in diameter will increase displacement to aprox 5780cc (rounded 5.8litre engine)

Also now designing their own custom hydro cams to trial when the engine is re-built to take things up another notch
 

·
Registered
Joined
·
1,245 Posts
Interesting, however I doubt there will be many, if any, owners willing to pay for such involved levels of modifications. I suggest they keep it as simple and inexpensive as possible.

I've been in touch with a manufacturer to reproduce tri y manifolds in 304 stainless steel for the 560 SL, and they would be willing to make them for under 350$ - notwithstanding the extremely low price, there was been virtually no interest in the 107 forum.

Sent from my MAR-LX1M using Tapatalk
 

·
Registered
Joined
·
11 Posts
$2700 for headers alone. Theres gonna be a handful of guys jumping on that. Amg pipes or euros pop up for alittle more than a grand on ebay occassionally. Hard to bite that cost for 10-15hp in a slow and heavy classic. Almost 5 grand for the full system from headers to the exhaust not including shop install fees, i dont see how there gonna sell honestly. Best of
Luck, and thank you carbou for the effort time and patience dedicated to this platform

Now if you guys came up with a turbo system rear mounted or something along those lines, with increases of 75-100hp that would be money i would def spend.
 

·
Registered
Joined
·
1,245 Posts
$2700 for headers alone. Theres gonna be a handful of guys jumping on that. Amg pipes or euros pop up for alittle more than a grand on ebay occassionally. Hard to bite that cost for 10-15hp in a slow and heavy classic. Almost 5 grand for the full system from headers to the exhaust not including shop install fees, i dont see how there gonna sell honestly. Best of
Luck, and thank you carbou for the effort time and patience dedicated to this platform

Now if you guys came up with a turbo system rear mounted or something along those lines, with increases of 75-100hp that would be money i would def spend.
I've asked to see if there is any interest in headers for 350$, not 2700, and basically no one is interested.

If people aren't willing to spend 350 on a set of headers, you can definitely rule out cams, high compression pistons, not to speak of boring out an engine...


Sent from my MAR-LX1M using Tapatalk
 

·
Registered
Joined
·
21,746 Posts
I've asked to see if there is any interest in headers for 350$, not 2700, and basically no one is interested.

If people aren't willing to spend 350 on a set of headers, you can definitely rule out cams, high compression pistons, not to speak of boring out an engine...


Sent from my MAR-LX1M using Tapatalk


If you really want to see the level of interest at $350, I think you should put together a full price list including the Timevalve exhaust system / down pipes that would be required to match pipes. Then you’ve got to market it AND wait.

In my experience of selling parts, you can’t force a sale to happen at any given point in time. But if you wait long enough people will come along, even at higher prices. This is what Carobu is doing. They are marketing their expertise in modifying m117 systems, and when someone comes along with some real money to spend, they are going to take their car to Carobu. I bet the LAST thing they want is to sell 20 sets of $350 parts that get installed incorrectly by back yard mechanics and little-to-no actual gains, basically tarnishing their name.

We have seen the simplest modification is the air filter. Who knew something so simple could lead to such significant gains.

And who really cares about the power rating of their car? Isn’t that kind of like measuring penis size? What I like, is feeling like the car has torque in the seat when you drop the pedal, and the motor revs high and fast when you are in gear (perception of power). I don’t see myself ever drag racing anyone to prove my car is faster (because it’s not, and never will be with electric cars today).

The irony is that I can get 90% of what I want with no engine modifications at all. All I need is a manual transmission and/or a high ratio differential. I don’t drive far enough ever in my classics to care about low ratio final drive.

I’ve got huge respect for what Carobu is doing. I just won’t be purchasing their stuff, not because I wouldn’t like to, but because I’m just being realistic about my frugality (cheapness). I know there are plenty of people spending over $50,000 on cars with m117 motors (or 3.5 m116) that would probably spend $20-30,000 for a Carobu rebuild instead of $10,000 for a metric motors or whoever is the top rebuilder these days, and they wouldn’t even think of trusting their motor to anyone who would do a rebuild for $3000-5000, despite plenty of them being great mechanic machinists.

While at it, spending $20,000, why not get those headers (reversible modification) or other internal performance enhancements. Right?

Edit: and do I want to buy those custom headers from Carobu for $3000 knowing I will get a great product? Or do I want to buy some questionable tri-y replicas with no guarantee to fit, knowing I I’ll probably have to hire the local exhaust shop to weld together some untested system that might kill any gains that the $350 manifolds provide?

I’m not the least bit surprised that the level of interest is virtually non-existent.

If you are willing to make an investment on your own, I bet you will ultimately sell 20 sets over about 18-36 months.
 

·
Registered
Joined
·
1,245 Posts
I think you have missed my point, don't know if you read my post, but I have no interest in making a financial gain from this - it is simply the pleasure of doing it.

If fact, if someone else is interested I'm happy to share the offers I have so far.

The idea is to send a set of tri Ys, have them copied, and after they have been test fitted, they would be purchased directly from the manufacturer, I have no involvement from there on after.

Making headers out of stainless steel isn't rocket science, but of course the headers alone are just the start of all the work.

A set of good headers for our engines should not cost more than those available to so many other V8s.

Sent from my MAR-LX1M using Tapatalk
 

·
Registered
Joined
·
11 Posts
And i agree 100%, especially not for a 30 plus year car that was designed for autobahn/ american highway cruising not racing. Brand new stainless longtube headers from kooks performance with x pipe on my vette cost me under $1500 installed. Im not paying double that for a a w126 with 250ish horsepower, no way in hell.

I like your idea of having the tri-y duplicated, thats a great idea. With a group buy of minimum 10 people i could see us paying between 500-700 for a nice set.
 
101 - 110 of 110 Posts
About this Discussion
109 Replies
18 Participants
S550Renntech
Mercedes-Benz Forum
BenzWorld.org forum is one of the largest Mercedes-Benz owner websites offering the most comprehensive collection of Mercedes-Benz information anywhere in the world. The site includes MB Forums, News, Galleries, Publications, Classifieds, Events and much more!
Full Forum Listing
Top