Would you recommend a gm turbo and spend the money for it? if so why or why not

[Husker6.5]

German....ehh?

Very close to Yiddish

Ich sprechen se mama lochen? Since Yiddish is a combination of High German, some Polish, some Russian and a little American English written normally in Hebrew, yes, knowing Yiddish makes understanding German a whole lot easier.

 

[Husker6.5]

Now back to topic. If one were running bone stock unmodified, normal daily type driving without towing massive loads, etc., then replacing a bad GMX with a new GMX isn't that bad of an option for normal Joe Schmoe from Kokomo who doesn't know better and was planning on selling it later. HOWEVER, if a person was to do any serious towing (if only occasionally), had started modifying the motor (exhaust, intake, chip/program, WMI, etc), or was seeking improved fuel mileage, then the only use for a GMX would be as an expensive boat anchor for the bass boat!

I have felt that 2000+ rpm choke out more than once on my least favorite on-ramp, I-80 getting on west bound at Exit 454 heading north up S. 13th St by Rosenblatt Stadium in Omaha. The ramp is a TIGHT 25 mph posted downward spiral off of 13th St that begins to spiral back up hill as you approach the merge lane because I-80 is steeply climbing up from the Iowa side of the Missouri River to the top of the bluff (~200' altitude gain in 3/4 mi.) at 20th St. Add to that that the merge lane is very short (the south bound 13th St. westbound I-80 ramp merges just past) there is three lanes of heavy westbound traffic always, and you MUST merge left just past where the southbound 13th ramp merges in because if you don't you're stuck in a mandatory exit lane for the Kennedy Freeway northbound. It's a bitch when traffic is light, and near suicidal when traffic is heavy, ESPECIALLY when you have two semi's in the two inside lanes dueling to see who can make it up the hill first where you're supposed to merge and get over two lanes at the same time! I have blasted up the end of that merge lane WOT billowing black smoke like an inking giant squid fleeing the dinner intentions of a hungry sperm whale, all the while wishing like hell that all that torque that was thrusting me up that merge lane at 35 mph in second just sort of disappeared as I crossed the 2100-2200 rpm threshold in third at 45 mph to be replaced by my "ink cloud" all while two semi's dueled in the inside lanes and the idiot asshole in the Honda Civic won't get the hell out of my blind spot or let me in to get over out of the mandatory exit lane!

My bucks are DEFINITELY being saved to get a better turbo for the Burb, as the guru of the "other" turbo knows from communications with me.

 

[Jorge6.5]

Turbo should help you get up that ramp with some ECM tune to match or u can just run them other cars off the road haha

 

[WarWagon]

I can't hardly sell my used GM3 for more than scrap metal.

In factory trim the 1993 is a dog all the way around even with 4.10's. After adding a Turbomaster and 1/2 turn on the fuel screw it feels quick unloaded from light to light. This is the only nice thing I will ever say about the factory turbo. It then falls over above 2200 RPM causing excess engine heat the cooling system has to deal with, reduced MPG, and painfully slow hill climbing loaded.

I feel sorry for anyone towing with a GMx no matter what they have done because they are leaving 10 MPH and 3MPG on the table that the engine cooling fan has to deal with. The feeling of dread before a mountain climb with the cooling fan screaming goes away with a larger non-factory turbo. You can only hold the wastegate closed for so long under load before the factory turbo overspeeds, becomes an air intake heater, and you have to open the wastegate. At this point ~2200 RPM you are at max boost and further engine RPM and load have to fight to get through the small wastegate hole. You can feel it.

The MPG with a factory turbo over a NA 6.2 also is ~1/4 less at 15 MPG vs 18 MPG.

The small hole for the wastegate to bypass the turbo has restriction written all over it. Restriction in the exhaust costs MPG and heats up the engine. As much heat can't escape out the restricted exhaust.

The only way I would ever run a GMx turbo again is with a manual transmission and lug the living hell out of the engine below 2200 RPM because that is the only place a factory turbo is worth anything. As these are a high speed diesel and cruise RPM is over 2200 RPM in top gear with 4.10's I can't see this being possible. The automatics shift to high RPM in a way that makes the engine's GM3 choke and ruin the benefit of a torque converter.

Word is Navistar went the other way with a turbo on one engine that was too large and made a dog that was really bad at altitude.

Smoke? With the fuel turned up the GM3 will start to smoke at altitude.

 

[3500GMC]

That's basically what I deal with for now. Except a fuel'd up 6.2 with big valves and ported to heck heads.. NEED MORE AIR.. I short shift the 4L80 as best I can to keep it below 2200 but then the 4.10's run short then it's fighting itself again.

I didn't even bother with a boost bolt om my GM-3. So what.. Have a gently used HX35w waiting in the wings that may help.

I run a ridiculous amount of adv too, Seems my long coarse threaded injectors are N/A 6.2 sized, so I can only imagine how prolonged the actual injection event is. If I keep the funky heads/injectors, I'd like to machine a set of bodies that are short and coarse to use the 6.5 nozzles and their variants. Maybe Mercedes nozzles? Idunno.

It's my science project, that I ride on.. What a mess..

 

[Husker6.5]

My only three power/economy "mods" for the moment: Waste gate wired almost completely shut (just a hair of slack for bleed off at high rpm to avoid over boost) after vacuum pump went tits up (CLEANEST I've ever seen the exhaust, until it gets above 2200 rpm under load). #9 resistor. Oiled gauze air filter with lid removed from K-47 airbox and cowl to hood gasket removed.

More to come as $$ permit. First up: Replace worn out IP to cure the TCC bucking problem and improve fuel mileage. #2, the rest of the 4" exhaust (I'm stealing the 3" down and first pipe off the custom system on my '94, need to buy a muffler eliminator and tailpipe from Heartthrob to finish out what I bought from them 8 years ago). #3, new (rebuild) injectors. #4, economy tune the ECM. #5, refresh my 203K 4L80E and performance update it. #6, gearing change taller from 3.73 F & R to 3.42 (would prefer 3.21, but can't find anyone who makes it for the 9.5" IFS, just for the 10.5" 14 bolt rear)

 

[Suburbank2500]

My only three power/economy "mods" for the moment: Waste gate wired almost completely shut (just a hair of slack for bleed off at high rpm to avoid over boost) after vacuum pump went tits up (CLEANEST I've ever seen the exhaust, until it gets above 2200 rpm under load). #9 resistor. Oiled gauze air filter with lid removed from K-47 airbox and cowl to hood gasket removed.

More to come as $$ permit. First up: Replace worn out IP to cure the TCC bucking problem and improve fuel mileage. #2, the rest of the 4" exhaust (I'm stealing the 3" down and first pipe off the custom system on my '94, need to buy a muffler eliminator and tailpipe from Heartthrob to finish out what I bought from them 8 years ago). #3, new (rebuild) injectors. #4, economy tune the ECM. #5, refresh my 203K 4L80E and performance update it. #6, gearing change taller from 3.73 F & R to 3.42 (would prefer 3.21, but can't find anyone who makes it for the 9.5" IFS, just for the 10.5" 14 bolt rear)

About the TCC bucking problem you describe,how does it act. Is it like shuddering, misfire ?

 

[Husker6.5]

About the TCC bucking problem you describe,how does it act. Is it like shuddering, misfire ?

See my thread in the 4L80E section. Far easier than rewriting everything over again.

http://www.thetruckstop.us/forum/showthread.php?33235-4L80E-TCC-Unlocking-defies-logic

 

[turbonator]

cant comment on the gm-x turbos because we went from N/A directly to aftermarket..... but have had them lined up beside many other types and sizes and can only say "yuck"....LOL... but on a side note they fill up the turbo shelves nicely and impresses the clients with quantity, so it is not all bad...LOL... actually been thinkin to build a custom header for our 86 jetta with the 1.9l and try a gm-x on there.... anyone got a spare?LOL....

 

[TrustySub]

I think 'buddy' said it the best. Aftermarket allows for more hp.
From my comparisons...every dollar spent towards aftermarket is a dollar reinvested for a happier tomorrow.

 

[GM Guy]

DID GM make a 1500 series truck with a turbo and a 3:08 gear? That might be a candidate for the factory turbo.

yep, got one! 1994 Chevy C1500 ECSB 6.5L TD (S code of course) 4L80E 10 bolt stuffed with a 3.08 gearset and a G80. has 280K, and only minor work done to rear (spider gears, IIRC) so much for the explodes while sitting 10 bolt/gov loc combo.

if bill heath needs a one year older twin to the LSR, mine is for sale!

but I do plan on fixing it, and I think a GM8 or GM5 will go on. need a restrictive turbo to keep spooled.

as far as a answer to the original question, yes, I would run a GM series turbo, but only for the reasons of cost. if I dont drive enough to justify a better turbo, then it doesnt get one. also being too broke to afford one factors in as well!