blackandgold51
1/2 ton status
Yes. Along with the heavy crap we don't need
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Is there ANY way you can make a 90' Suburban V1500 4x4 700r4 350 Tbi V8 gas Fuel Efficiant some?
- Thread starter blackandgold51
- Start date
Yes. Along with the heavy crap we don't need
blackandgold51
1/2 ton status
The new ones are noticeably lighter?
One time a guy that had poplocked my suburban(which is a 1990 V1500 4x4 350 ) when my keys were locked inside , said that today's Suburbans look short in length compared to mines. Along with size overall
blackandgold51
1/2 ton status
6.2 engines are good. Compared to an sbc, they require slightly different (not particularly worse) maintenance, and they aren't drag racing engines. They are designed for mileage and 1980s-era towing. They are very simple and dependable. It has the simplicity of a 1-wire engine with the dependability of fuel injection. No sensors, no tuning, just put 12V on the fuel solenoid and it runs. As a rough comparison, there are about a 1/2-dozen specific issues that can arise with a 6.2 engine. If you look at your current TBI engine, and start counting sensors, you'll find that it has a couple dozen potential failure points. In neither case do you expect all of them to fail, but you know that some of them will eventually.
I don't think you'll be any less happy with a 6.2 than you are with your current engine. You should expect to change a set of glow plugs (like spark plugs, but less often). If you buy an older one (pre-1988) you may have to learn how to mechanically prime the fuel system at some point. Harmonic balancer should be replaced if it's loose or knocking. But that's true for any engine.
You may or may not find the 6.2 a good fit for your purposes. But don't go around thinking it's hard to work on, or that it's a bad commuter engine just because it won't beat a 454 in a quarter mile. And definitely don't go around thinking it's an overbored 350 block that likes to blow up. Not sure how that rumor got started.
I think(due to research ) that the rumor go started because of of the Oldsmobile 350 v8 diesel before the Detroit Diesel 6.2
blackandgold51
1/2 ton status
Premium fuel in a 350 gas engine of the era(1989-91) is a good choice because these engine don't agree with unleaded gas.
If you put unleaded fuel in and I you're going up a hill or bridge while hard on the throttle(or accelerating hard) you'll hear rattling like sounds which sounds like rocks being thrown around in the engine. Basically pinging. And a lose of some power.
But put in premium fuel the engine won't have any noise and have good power .
This is the second suburban/engine that has done that. The last one I had was a 90' GMC R1500 350 700r4. Same thing happened . and the engine in that one was a good used engine dropped in that had over 74000 miles on it when I got it 2 years ago. Before I sold the suburban two years ago to get the one I have now
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Even that engine wasn't based on the sbc (though it did share tooling). It did have a list of issues though. I've had a number of people tell me my truck is worthless because they think I have one of those Oldsmobile engines.
http://www.dieselhub.com/idi/olds-diesel.html
Me too...so many of those 350 Olds diesels blew up within a year with low miles around here,it stained GM's reputation for diesels in light duty trucks for decades..
The 6.2 was "designed" by Detroit Diesel,but not built by them...a lot of people think they are a Detroit,but they aren't..
I wish GM had put the 3-53 and larger Detroits in their pickups,after seeing the trucks on Youtube that someone swapped one into..love that 2 cycle scream!..
..
The 6.2 was "designed" by Detroit Diesel,but not built by them...a lot of people think they are a Detroit,but they aren't..
I wish GM had put the 3-53 and larger Detroits in their pickups,after seeing the trucks on Youtube that someone swapped one into..love that 2 cycle scream!..
..
Regulations requiring the phaseout of leaded gasoline were issued in 1973 (http://www2.epa.gov/aboutepa/epa-requires-phase-out-lead-all-grades-gasoline). No American vehicle from the era you are describing was designed for leaded fuel. It ruins catalytic converters, so vehicles equipped with such are for use with unleaded fuel only.
Pre-ignition and knock both do sound like what you're experiencing. And I'm intrigued as to why your trucks are different, as other trucks from your series do not require high-octane fuel. But it's not honest to blame it on unleaded fuel. This truck is more than a decade too young for that.
Me too...so many of those 350 Olds diesels blew up within a year with low miles around here,it stained GM's reputation for diesels in light duty trucks for decades..
The 6.2 was "designed" by Detroit Diesel,but not built by them...a lot of people think they are a Detroit,but they aren't..
I wish GM had put the 3-53 and larger Detroits in their pickups,after seeing the trucks on Youtube that someone swapped one into..love that 2 cycle scream!..
I think the reason that folks think they're Detroit Diesels is that GM marketed them as such in their advertising.
Just don't tell Martin that!
blackandgold51
1/2 ton status
Idont have cat converters. Neither have I Did on the last one. I took them off before I had flowmasters (regular 40) installed.Regulations requiring the phaseout of leaded gasoline were issued in 1973 (http://www2.epa.gov/aboutepa/epa-requires-phase-out-lead-all-grades-gasoline). No American vehicle from the era you are describing was designed for leaded fuel. It ruins catalytic converters, so vehicles equipped with such are for use with unleaded fuel only.
Pre-ignition and knock both do sound like what you're experiencing. And I'm intrigued as to why your trucks are different, as other trucks from your series do not require high-octane fuel. But it's not honest to blame it on unleaded fuel. This truck is more than a decade too young for that.
Plus I guy I know has a 1975 Impala with a rebuilt 350 with a edlebrock carb that does the same with unleaded
blackandgold51
1/2 ton status
I forgot to mention that the engine in my 90 v1500 4x4 was also rebuilt last year(2014)Regulations requiring the phaseout of leaded gasoline were issued in 1973 (http://www2.epa.gov/aboutepa/epa-requires-phase-out-lead-all-grades-gasoline). No American vehicle from the era you are describing was designed for leaded fuel. It ruins catalytic converters, so vehicles equipped with such are for use with unleaded fuel only.
Pre-ignition and knock both do sound like what you're experiencing. And I'm intrigued as to why your trucks are different, as other trucks from your series do not require high-octane fuel. But it's not honest to blame it on unleaded fuel. This truck is more than a decade too young for that.
Whether you actually have them doesn't matter. Any vehicle designed for such will be marked as "Unleaded Fuel Only." Is your gauge different?
Different engine generation, different decade, different car. Not really relevant to you and your engine. And are we talking stock engine setup or rebuilt? A rebuilt engine may very well have a different compression ratio.
blackandgold51
1/2 ton status
Stock. And I did mention before that the last suburban (90 R1500 Rear wheel drive 700r4) done the same thing before and after a new engine was installed with 74000 miles. As for the Impala, his engine is exactly like mines. It was also fuel injected however he switched to carb(not to mention he's not a fan of fuel injected )
I think we're talking past each other here. I'm not doubting that you are having some sort of knocking or pinging (as per your description). What I'm saying is that all three of the vehicles you have mentioned were designed for use with unleaded fuel. You may be having issues with low-octane fuel, and I'm curious to find out why, as many trucks of that era don't. But lead is not the culprit here, nor would adding lead be a particularly good solution for your problem.
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black dawg
1/2 ton status
If the timing is set correctly, pinging in a tbi 350 is usually caused by the egr system not working correctly.
blackandgold51
1/2 ton status
I'll check that
blackandgold51
1/2 ton status
So basically the Detroit diesels are NOT Detroit diesel engines and was instead made by gm itself?I think the reason that folks think they're Detroit Diesels is that GM marketed them as such in their advertising.
Just don't tell Martin that!
There is a disagreement on this topic that pops up on this board from time to time. Detroit was a division of GM at that time, so it seems like an irrelevant issue to me. But others get fired up about it.
Easily verifiable facts include:
GM trucks came with 6.2 engines
GM advertised them as "Detroit Diesel" engines (whatever that means).
Detroit does not currently maintain any support for 6.2 or 6.5 engines, while GM does.
I'm not sure exactly what level of involvement Detroit had in the design & production of these engines back then. I've heard stories and hearsay with several different angles, but nobody has offered a concisely-written authoratative history of the 6.2 engine, AFAIK.
blackandgold51
1/2 ton status
Short of like Tom Clancy putting his name on a video game while he has no involvement in it
If your engine is pinging under load then you need to check your timing. A stock TBI engine should be set at 0 degrees before top dead center with the ignition bypass disconnected. If you have it set higher than that to try and gain additional performance (which you can get away with up to around 3 or 4 degrees extra timing) then you will risk pinging. If your engine is pinging then your knock sensor will detect it and retard your timing anyways. If you've got your timing so advanced that the ECM cannot retard enough to stop the pinging before you hear it then that is definitely your problem. If you need / want additional timing on a TBI equipped 350 then you need to get it tuned for timing. Adding baseline timing by advancing the distributor will just cause problems.
Either way, I can assure you that your stock 1990 TBI 350 does not require premium fuel. If your engine was built up enough to require premium fuel then your TBI system would not be able to run it with a stock tune anyways. You're just wasting money burning premium fuel which, by the way, has a higher heat of combustion and may potentially produce less power and efficiency than burning the correct octane fuel. Your engine will be perfectly happy with 87 octane and the correct timing settings. Your buddy's Impala likely suffers the same trouble with incorrect timing maps and being too advanced to try and gain some low end performance. He may need to re-weight / spring his distributor to adjust the timing curve to better suit his engine.
Adding extra fuel economy to your suburban will require an engine swap to a more modern engine platform or switching to a diesel. But either one of those options will cost thousands of dollars which you could simply just spend on fuel instead. Infact, you're probably better off to run your burb just as it is vs buying a newer and more fuel efficient vehicle. Gasoline is one of the cheapest parts of driving.
Either way, I can assure you that your stock 1990 TBI 350 does not require premium fuel. If your engine was built up enough to require premium fuel then your TBI system would not be able to run it with a stock tune anyways. You're just wasting money burning premium fuel which, by the way, has a higher heat of combustion and may potentially produce less power and efficiency than burning the correct octane fuel. Your engine will be perfectly happy with 87 octane and the correct timing settings. Your buddy's Impala likely suffers the same trouble with incorrect timing maps and being too advanced to try and gain some low end performance. He may need to re-weight / spring his distributor to adjust the timing curve to better suit his engine.
Adding extra fuel economy to your suburban will require an engine swap to a more modern engine platform or switching to a diesel. But either one of those options will cost thousands of dollars which you could simply just spend on fuel instead. Infact, you're probably better off to run your burb just as it is vs buying a newer and more fuel efficient vehicle. Gasoline is one of the cheapest parts of driving.
