BAD 300E project commenced - Page 8 - PeachParts Mercedes-Benz Forum

BAD300 · #**106** 08-10-2010, 01:43 AM

After talking over with workshop again today & another Merc owner have decided to let go of the HP bar & concentrate more on the sprint

The heat scare will be sorted by larger IC.

Amazingly. The performance difference between the 30 series & the 35 series DOWN LOW & MID sincerely negligible! I actually found an EVO owner who fitted both GT's to same car & powerband on dyno readings were almost identical :shock: only real difference, as you'd expect (& I'm positive you'd know) is right @ the top-end say, 5500-6000rpm. This range is limit for my application anyway. Thois is why I chose the larger compressor housing/wheel to get that power down.

I am going for the smaller .63 a/r exhaust! If I don't like the responsiveness than I will simply swap it out to the .84 housing & be done with it. The only trade-off will be top-end power seen only in dyno chart & good only for track/drag use.

P.S. I can always pull more boost though 8) hehe....to close the gap a little.....

P.P.S.S. btw......has it occurred to anyone to get relief from lag......just change down a gear haha....

MagnumPI · #**107** 08-10-2010, 06:22 PM

Interesting. So, that basically says the 30 is a *****in' turbo if it's hanging with the larger series.

Should be fun either way. Can't wait. It'd be better if my turbo project could move forward, and the guy making my manifold would hurry up...

BAD300 · #**108** 08-10-2010, 07:29 PM

Quote:

Originally Posted by MagnumPI

Interesting. So, that basically says the 30 is a *****in' turbo if it's hanging with the larger series.

Should be fun either way. Can't wait. It'd be better if my turbo project could move forward, and the guy making my manifold would hurry up...

know the feelin'

You don't wanna pressure them but it's like.....hurry the hell up man

One week their quiet then soon as you take your car in.....their busy

I asked the turbo/fabricator guy "how long....how many months will it be mate...." he answers, "couple a months......4, could be here for til' whenever!"

I said well why? He then wanted to know whether I want it done real soon? I'm like....hell yeah...."OK" he says......1 month sound good?

.......YEAH! .....hilarious isn't it?

BAD300 · #**109** 08-11-2010, 06:48 PM

HP/KW's aside, I'm tempted to try 16-17psi to allow the GT35 to work closer within it's efficiency range. Have noted people saying 14-15psi, or 1 bar, is a reliable boost to run with this engine in stock, unopened trim. The only member I have noted however going past this is Roman (Pumpish) going to 20-21psi. Not sure (he hasn't replied) whether he used the custom steel head gasket or if original ne is in place? The stock 12V running gear, especially the diff size, is concerning me a tad @ these higher boosts

This I need to decide in the next few weeks.

Since I'll be using the MT8 for timing control. Most will be aware of the benefits of software -programmable ECU's over the basic timing computer like the MSD range sell that V8's employ (as in the original set up on my car by previous owner) Basically you set the timing to retard say, 2 degrees @ a given psi/bar boost level. Ie: for each 5 psi of boost, the timing is retarded 2 degrees. Works OK but not alot of control over AFM's. No ability to accurately map parameters like you can if you use the stand alone ECU's. What really sold me was with the sand alone, you can pretty much 'guarantee' the engine is going to be provided with correct desired 'AFR's right through the rev/boost range. Not just better performance but the safety/piece of mind of knowing car is told exactl what to do @ any given time & NEVER lean out

Guess I'll soon find out

P.S. my head hurts atm

Just reading on how various exhaust housing A/R's play @ different boosts & the danger of heat/detonation when exhaust flow is restricted! Again. With my build. There is not much tech stuff to sort through. The main engines that closely match the M103 are Supra 2.5L 1jz engines. The 3.0L 2jz heads flow better so aren't are real hot comparison to the lazy-ass M103 head lol. Also. LPG inherently poses less detonation risk anyway so alot of stuff I read concerns pump fuel & therefore furthers to my 'guessing game crusade' I've embarked upon haha.....NOT

What is for sure (yet, once again, little tested on the Merc) is the custom exhaust will greatly assist exhaust flow & therefore ease the horrid problem of exhaust heat/restriction greatly so.......again, except for Pumpish's projects, uncharted waters I paddle

P.P.S.S. Also. A bigger compressor housing with smaller wheel, as seen with the GT30 (afaik, uses same comp housing size as GT35?) turbo would be better suited for those wnating to run higher boost. Me on the other hand, want to keep boost down (due to stock compression) so this is why I am opting for the GT35 over simply settling for the GT30. Keeping in mind down low & mid, powerband seems pretty much similar. A rare case, as mentioned by another where going bigger turbo than you might think to is OK

JayRash · #**110** 08-12-2010, 02:37 AM

Well with a wet manifold setup like ur setup i doubt 1 bar boost will be reliable, the engine will take the boost if u swtich to an MS controled ignition/injection setup and a proper I/C. otherwise just go for lower boost and enjoy a seriously quick car.

BAD300 · #**111** 08-12-2010, 02:38 PM

Quote:

Originally Posted by JayRash

Well with a wet manifold setup like ur setup i doubt 1 bar boost will be reliable, the engine will take the boost if u swtich to an MS controled ignition/injection setup and a proper I/C. otherwise just go for lower boost and enjoy a seriously quick car.

Jay, I'll be running a stand alone MT8 so I would have thought reliability would be attainable? Also. Intercooler is being upgraded to a larger one.

MagnumPI · #**112** 08-12-2010, 02:56 PM

What's this "high" boost I keep seeing? My TT(with a Volkswagen engine, for god's sake!) had stock hard parts pushing 24psi. Out of the gate it was 14psi! 9.2 is a boost ready CR. It'll be fine. With JZ engines, it's all about the same 1J or 2J both have similar head flow numbers. They jump around all over the place.

The 24V drivetrain swaps right in doesn't it? I think the case is about the same, the vent's in a different place. Halfshafts might also differ. But the factory prop shaft is a joke anyway, at least the donuts.

JayRash · #**113** 08-12-2010, 04:44 PM

Magnum, the M103 will take high boost, but not in CIS form or a wet manifold setup for its hard to get a good tune with those setups. the pistons are tough but they are cast aluminum ones so if the engine leans out a piston, it will melt the ring seats easy.

JayRash · #**114** 08-12-2010, 04:50 PM

Quote:

Originally Posted by BAD300

Jay, I'll be running a stand alone MT8 so I would have thought reliability would be attainable? Also. Intercooler is being upgraded to a larger one.

its not just the ignition im talking abt, thou that is a gr8 move u did there. its injection, in cis its really hard to get fuel at topend to cover anything over 8psi (i know u dont have CIS, IIRC u have a mixer set up) with this that means ur running some sort of a wet setup and as such it will be hard to get all pistons fed with enough fuel so as not to melt the pistons. thats y i said stay low on boost and enjoy a reallly quick car

BAD300 · #**115** 08-12-2010, 05:57 PM

Quote:

Originally Posted by JayRash

its not just the ignition im talking abt, thou that is a gr8 move u did there. its injection, in cis its really hard to get fuel at topend to cover anything over 8psi (i know u dont have CIS, IIRC u have a mixer set up) with this that means ur running some sort of a wet setup and as such it will be hard to get all pistons fed with enough fuel so as not to melt the pistons. thats y i said stay low on boost and enjoy a reallly quick car

This is where it moves into confusing ground for me. Jay. I can't speak for the injection kits over your side of the country, or US for that matter but kits sold here are woeful! My workshop guy knows distributors of the LPI set ups here & they are cheap-ass, unreliable, over-priced & will not out-perform the current mixer set ups we have here. The parts even are pathetic. The V8 dragsters running LPG down here are using the mixer set ups & consistently out-performing injection LPG @ the drags. As i said. It may be the injection set ups are not sold the same everywhere? Also. 2 highly regarded workshops stated the same thing concerning set ups. So. This wasn't an option I'm afraid for me

Workshop ensures the cylinders will get enough LPG to them with modified set up they're doing. I know we spoke about the inlet manifold dilemma early on in the thread but workshop is re-fabricating the original inlet manifold. To be precise. All runners are chopped so they are now just 3-4" runners with turned ends. A Boxy Plenum will sit over these, angling inwards towards the last cylinder. Mixer feeds fro the front closest to cylinder 1. Along with larger feed lines etc. Apparently this will safeguard against leaning out.

Don't worry. I am relaying concerns you have mentioned to workshop so I will just have to wait & see. I will however be keeping boost down to begin with!

Bottom Line: I wish I didn't need to deal with the LPG but you guys know well I have to! I don't wanna be paranoid over whether cylinders get the gas & this is why I'm paying a fortune to get an expert to do the job. Otherwise it would have been all over before I started! I'm not paying an expert to fluk the thing up after all. I have to go with him on this. You have to imo leave LPG to the experts

No matter what you here or read. Alternative is to do nothing

Again. It craps me off having to fix this car up after being raped so badly by the previous owner.......

BAD300 · #**116** 08-12-2010, 08:28 PM

Just a thought. If boost is an issue. Surely it's only if car was track driven or held @ this boost for some period of time? If it is only boosting high when kicked in the guts & @ higher revs. As it's driven on the road only. This would be rare. If it was driven @ say, half throttle & boost was pulling @ 10psi. This would probably be the vast majority of range the car was driven at. With this in mind. Perhaps the boost issue really isn't that of an issue? Yes if it was driven hard & pushed alot but here in Ausland. Cops will slap a EPA order on you quick as look @ you if your caught screwin' around.

Too low a car or too noisy a car is 2 main reasons folk get nabbed. I wouldn't want them to have too close a look @ this set up even if it is eventually Engineer Certified. I am keen on keeping the sleeper look. Sporty accent but still relatively calm from the outside. I'm not a fan of cops & their bullcrup fines cause your rolling 5kms over speed limit

Having said this concerning boost. The dyno will still be a bit scary on the engine I think

MagnumPI · #**117** 08-13-2010, 02:13 PM

Jay, I was just commenting on the boost itself. I know CIS is garbage, I still take the stance it needs proper EFI before turbos are even considered. It's just too much of a headache finding ways it can be done. And now with megasquirt, cheaper to do it right.

RBYCC · #**118** 08-13-2010, 03:50 PM

Quote:

Originally Posted by MagnumPI

Jay, I was just commenting on the boost itself. I know CIS is garbage, I still take the stance it needs proper EFI before turbos are even considered. It's just too much of a headache finding ways it can be done. And now with megasquirt, cheaper to do it right.

CIS is far from garbage...
More a challenge to keep something "period" and not build a "grenade"

TurboTechnics came up with a great solution for fuel enrichment using CIS over twenty years ago.
Replace the rubber boot between the air valve assembly and the throttle body with an aluminum casting that holds two additional injectors.
The shortcoming at that time was the additional injector control.
Now you can use a compact solid state additional injector controller firing the two injectors...it's a perfect match.
Can't be any simpler...three wires and vacuum/boost tube to the internal MAP sensor on the controller and you're good to go.
Program with a laptop and it will match any EFI for enrichment.

My last pulls on a Mustang load dyno gave 262RWP and 302 torque at only 7lbs boost.
Compared to the stock non turbo base line pulls and the output has doubled.

JayRash · #**119** 08-13-2010, 06:57 PM

I love the cis, dont forget my car covered over 25000km under boost and severe abuse for it was my daily driver and i drove the car just as hard as it was when stock, if not harder due to all the races i was called for since it was the only boosted w124 in my country. and it did that without even using extra injectors, thou i do tell u thats the worst option to go with since tuning cis to this level of output will make ur hair fall

and turn the few left gray since the setup on the m103 was never made to see positive pressure. but i loved it, i miss it.

many claim to have run high boost on those engines, and the m104, but i for one still think the piston ring lands are the weakest point in the engine. the rods are strong and will take the boost, the pistons even are tough and will take the extra heat, but the ring lands might crack if the engine is run under high boost for long periods. but hey thats my say, and i might be wrong.

ED, how many miles has your covered with the turbo setup? my car did just over 25000km taking the engine from abt 360000km to just over 385000km before i broke a perssure ring, and that only happened after i upped the boost to abt 10-11 psi and had to use the alc injection kit to make up for the needed fuel, and on that day the engine sat on the 7000rev limiter for longer than i would recommend in 2nd gear on burn out.

RBYCC · #**120** 08-13-2010, 10:56 PM

Jay

I've probably only done about 4K miles since the TT install...nothing in the past year !!!

Most was done at 7psi boost with about 1K miles at 10psi boost.

When I get the widebody build done it will be back on the dyno...

New stuff since the last pull is the Hallman Pro RX MBC, try out a hotter Nology coil and a set of Beru S1K silver electrode plugs.
Have everything needed to install a water/meth spray injection.

I don't push it that much but probably 10psi will be my max boost setting with the water/meth coming in around 8-9psi.

Once on the dyno I can play with the variables...looking to increase power by about 10% and I'm done !!!!

If I want to go really fast I just drive the Black Series !!!!

Getting old !!!