My 2.8L big bore update
04-21-2004, 12:30 AM
#16
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Ah ok, sorry I get defensive about SIR944. Yeah it would be interesting to see a new watercooled coupe. lol
I remembered hearing something about a Porsche 4 door sedan? I cant see the lines of a Porsche on a sedan. Makes me cringe.
I remembered hearing something about a Porsche 4 door sedan? I cant see the lines of a Porsche on a sedan. Makes me cringe.
04-21-2004, 12:32 AM
#17
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Originally posted by fluid15
That looks like a fun project! I wish I had the knowledge & time to do something like that. And on a Porsche no less! Those Turbos sure were nice cars, too bad they're a thing of the past. I sorta wonder how they'd look today if they continued to evolve (from a design standpoint).
That looks like a fun project! I wish I had the knowledge & time to do something like that. And on a Porsche no less! Those Turbos sure were nice cars, too bad they're a thing of the past. I sorta wonder how they'd look today if they continued to evolve (from a design standpoint).
Originally posted by Tom M'Guinn
Can you explain what a Rothman tranny is? Thanks.
Can you explain what a Rothman tranny is? Thanks.
04-21-2004, 12:35 AM
#18
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Originally posted by rage2
It's the stronger tranny from the Canadian Rothmans Cup Series racecars.
It's the stronger tranny from the Canadian Rothmans Cup Series racecars.
04-21-2004, 12:44 AM
#19
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Yes they're Porsche parts, basically took a Turbo tranny and beefed it up. Unfortuantely, they only made 36 of the cars... I was lucky enough to know someone that had one. I was told that the parts are next to impossible to come by. www.asaurus.com has some info, but the site is in french, and caters more to the french escort cup series (maybe same car, not sure).
You're probably better off picking up a strengthened tranny from Powerhaus 2 or something... they'll be able to build you an even stronger box than this. I actually came real close to buying a PH2 944 S2 gearbox, with cooler, and strengthened/shotpeened 1st and 2nd on a custom shaft... then this tranny came along locally for a bit cheaper and I ended up taking this one instead.
Edit - Forgot to answer the cam tower question. The entire thing was powder coated, then the Porsche letters were sanded back down to metal.
You're probably better off picking up a strengthened tranny from Powerhaus 2 or something... they'll be able to build you an even stronger box than this. I actually came real close to buying a PH2 944 S2 gearbox, with cooler, and strengthened/shotpeened 1st and 2nd on a custom shaft... then this tranny came along locally for a bit cheaper and I ended up taking this one instead.
Edit - Forgot to answer the cam tower question. The entire thing was powder coated, then the Porsche letters were sanded back down to metal.
04-23-2004, 05:04 AM
#22
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Rage2 and I have the identical configuration (not the same turbo, but similar, and I've got 84-lb/hr injectors). I've been running it at low 10-12psi for the last month to break it in gently. Haven't really opened it up until the OTC this last week. Max boost hits at a nice and low 2800rpm in 4th gear. Figured the larger 2.8L displacement would get more exhaust -flow to spool up the larger turbos (would be about 3300rpm on 2.5L engine).
Then some strange exhaust leak developed somewhere when the car's been flogged for 5 minutes or more. I think the heat opens up a flange somewhere and lets exhaust going to the turbo leak out. At the end of the 25-minute track sessions, I wouldn't get max-boost until 5000rpm or so. And the car would sound like a boat or tractor when pulling into the pits. Gonna track down that leak sometime this week. Perhaps the ceramic coated headers, crossover, turbine-housing and down-pipe may be holding in more heat and causing some joint to expand more than normal.....
Could also be because I re-used the exhaust crush-rings when I did an emergency oil-pan gasket replacement Monday night after Las Vegas (engine-builder used the wrong sealant). I actually ended up re-installing the OEM oil-pan gasket I had saved from the 1st time I replaced the rod-bearings (installed with elephant-snot). Held up fine for the rest of the OTC.
I don't think it's crankcase pressure that blows out these gaskets, because the bulging parts are right next to the rod-journals. I think adding the extra 1/2-quart of oil in Las Vegas allowed more oil to be splashed around on the inside by the crank, and that's what blew out the gasket...
BTW, from what was mentioned in Roco16's oilpan gasket thread, did anyone ever compare the "good" vs. "bad" oil-pan gaskets? What's the difference? Any pictures?
Then some strange exhaust leak developed somewhere when the car's been flogged for 5 minutes or more. I think the heat opens up a flange somewhere and lets exhaust going to the turbo leak out. At the end of the 25-minute track sessions, I wouldn't get max-boost until 5000rpm or so. And the car would sound like a boat or tractor when pulling into the pits. Gonna track down that leak sometime this week. Perhaps the ceramic coated headers, crossover, turbine-housing and down-pipe may be holding in more heat and causing some joint to expand more than normal.....
Could also be because I re-used the exhaust crush-rings when I did an emergency oil-pan gasket replacement Monday night after Las Vegas (engine-builder used the wrong sealant). I actually ended up re-installing the OEM oil-pan gasket I had saved from the 1st time I replaced the rod-bearings (installed with elephant-snot). Held up fine for the rest of the OTC.
I don't think it's crankcase pressure that blows out these gaskets, because the bulging parts are right next to the rod-journals. I think adding the extra 1/2-quart of oil in Las Vegas allowed more oil to be splashed around on the inside by the crank, and that's what blew out the gasket...
BTW, from what was mentioned in Roco16's oilpan gasket thread, did anyone ever compare the "good" vs. "bad" oil-pan gaskets? What's the difference? Any pictures?
04-23-2004, 11:39 AM
#24
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Rage & Danno,
What boost levels are you guys planning to dyno at ? Since we all 3 have the same 106 mm block, it would be nice to compaire our complete setup.
I received new rings yesterday (will install soon) and I hope to correct the blow-by problem I have.
When I do the break-in this time, I am thinking about following the Moto-Tune guys advice on a hard run in but low boost.
What boost levels are you guys planning to dyno at ? Since we all 3 have the same 106 mm block, it would be nice to compaire our complete setup.
I received new rings yesterday (will install soon) and I hope to correct the blow-by problem I have.
When I do the break-in this time, I am thinking about following the Moto-Tune guys advice on a hard run in but low boost.
04-23-2004, 02:57 PM
#25
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Yeah, I think due to the lower-tech nature of the steel sleeves and normal pistons & ring packages, we can use the more traditional hard break-in procedure. I think I certainly did that at the OTC last week after a month or so of gradually increasing the load on the engine.
I'm planning on dyno-testing at 14psi, 18psi and 21psi since those falls on different load-rows on the 3D maps on the MAP computer. This will allow me to fully optimize the last three rows on the maps. All three boost-levels use the same underlying Motronic WOT/full-throttle 2D fuel-map, so the MAP computer effectively gives me three different adjustment curves of the same fuel-map based upon boost-pressure. This will also provide a smoother transition on & off full-boost as well. I'm gonna do a compression check and see how the rings have seated after my hard break-in. Got 130psi before, target is about 160-165psi or so.
I'm planning on dyno-testing at 14psi, 18psi and 21psi since those falls on different load-rows on the 3D maps on the MAP computer. This will allow me to fully optimize the last three rows on the maps. All three boost-levels use the same underlying Motronic WOT/full-throttle 2D fuel-map, so the MAP computer effectively gives me three different adjustment curves of the same fuel-map based upon boost-pressure. This will also provide a smoother transition on & off full-boost as well. I'm gonna do a compression check and see how the rings have seated after my hard break-in. Got 130psi before, target is about 160-165psi or so.
04-24-2004, 01:13 PM
#26
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I'm going to hard break in my motor at 6psi (wastegate spring)... I'm hoping I'm not gonna have any blow-by problems, since I got my specs straight from John Anderson.
Like Danno, I'll be dynoing at a few boost levels, then interpolate the in between cells. I have a lot of boost level rows on SDS, and don't feel like doing 20 runs
.
As for the street, I'm gonna push as hard as I can on 94octane. Hopefully I'll see 15psi reliably, and hopefully I'll see somewhere near the 400whp mark. That's the goal of this exercise... 400whp on pump gas. As for race gas, I'm gonna push it as far as the turbo/injectors will take me. I'd like to have that "World's faster 944" title... but not sure if the turbo I have is enough to do the job.
Like Danno, I'll be dynoing at a few boost levels, then interpolate the in between cells. I have a lot of boost level rows on SDS, and don't feel like doing 20 runs
.As for the street, I'm gonna push as hard as I can on 94octane. Hopefully I'll see 15psi reliably, and hopefully I'll see somewhere near the 400whp mark. That's the goal of this exercise... 400whp on pump gas. As for race gas, I'm gonna push it as far as the turbo/injectors will take me. I'd like to have that "World's faster 944" title... but not sure if the turbo I have is enough to do the job.
04-25-2004, 01:45 AM
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Stock turbos are fine to run @ 18psi on 91 octane with good tuning, correct? Why can you only run 15psi on 94 octane?? Does it have something to do with weaker cylinder walls due to the porting, or is it because of the larger turbo? (Still learning as I go along...) 
04-25-2004, 02:14 AM
#28
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Originally posted by rage2
Hopefully I'll see 15psi reliably
Hopefully I'll see 15psi reliably
I think reliably is a very key word.
It will be fun to compare our dyno's all 3 of us with 106mm bores.
Rage with SDS,
Danno with Link MAP ?
Me with a Vitesse MAF- SMT6
04-25-2004, 02:39 AM
#29
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Just a question, can you install a 3.0l crank and keep the same size pistons, rods etc....? it would give you a 2.6 over all? but racing pistons, rods etc? possible without overboring?
04-25-2004, 03:10 AM
#30
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rage-
How does this WG setup work? Is that just a "muffler" on the end of it?
http://www.virgeweb.com/rage2/944t/2...embly%2014.JPG
What is the filter under the intake?
http://www.virgeweb.com/rage2/944t/2...20Car%2004.JPG
Nice pics!
How does this WG setup work? Is that just a "muffler" on the end of it?
http://www.virgeweb.com/rage2/944t/2...embly%2014.JPG
What is the filter under the intake?
http://www.virgeweb.com/rage2/944t/2...20Car%2004.JPG
Nice pics!