okay, just wondering what rpms things start failing at. what is the max effective rpm on all stock components?
I'd like to know the 1st thing that would fail at a given rpm. assuming I re-enforced the first thing, whats the second? and if I re-enforced the second, whats the third? (So on and so fourth...)
Im pretty sure the crank is in there, as well as the valvetrain (because of valve float) and fasteners (bolts, studs, etc). I just want to set an order on things that are expected to fail.
What if I re-enforced all of those components? what would be the max effective rpm?
The rod and main bearings fail at high RPMs. Due to the junk bearings used from factory and most cheap replacements.
On that note... When main bearings fail - crank walks around and ruins the bearing journals. And most likely the other bearings/journals. When rod bearings fail - rods tend to fail at the rod cap by getting stuck somewhere in the block during rotation and breaking. When rods fail - piston cups tend to take a beating and bust apart.
Also note: At any higher RPM the rods have enough momentum to crash through the oil pan and/or block.
You may ask how i know this..... These are the reasons my 86 SE now has a built 3.4 in it.
------------------ Cody - 86 SE 3.4pr/4 speed
[This message has been edited by 86fiero3.4 (edited 11-15-2012).]
What does it matter, since you will make no power at anything at or above the stock limit.
Exactly. While you can rev it.. there isnt any point in doing so. IIRC peak TQ is made at 3500rpm. You want your up shifts to drop the RPM as close to the peak TQ. There is no need to go past the indicated redline.
The biggest thing I have found is the coil, when I swaped to DIS it pulls all the way to redline now.
FYI 85-87 RPM limit is 6012 in the ECM, 88's have no rev limit. So everyone who says they rev it higher than that either has an 88 ECM, their ECM reprogramed, or is just flat out lying. Mostly the later.
The biggest thing I have found is the coil, when I swaped to DIS it pulls all the way to redline now.
FYI 85-87 RPM limit is 6012 in the ECM, 88's have no rev limit. So everyone who says they rev it higher than that either has an 88 ECM, their ECM reprogramed, or is just flat out lying. Mostly the later.
Is an 88 ECM considered an upgrade for 85-86 V6's? I have an Auto Formula and an Auto 86 GT. Would that be a direct swap or should I change PROM's? I don't know one auto trans from the next.
You want your up shifts to drop the RPM as close to the peak TQ.
Upshifts should be made such that power before the shift and power after the shift are the same.
The stock engine makes peak power at 4500 RPM, and the neck of the upper intake manifold where it sidesteps the distributor chokes it above that. No sense in revving higher than 5500 on a stock engine, as the power/torque drop off dramatically above 4500.
Originally posted by 86fiero3.4: The rod and main bearings fail at high RPMs. Due to the junk bearings used from factory and most cheap replacements.
On that note... When main bearings fail - crank walks around and ruins the bearing journals. And most likely the other bearings/journals. When rod bearings fail - rods tend to fail at the rod cap by getting stuck somewhere in the block during rotation and breaking. When rods fail - piston cups tend to take a beating and bust apart.
Also note: At any higher RPM the rods have enough momentum to crash through the oil pan and/or block.
You may ask how i know this..... These are the reasons my 86 SE now has a built 3.4 in it.
depends on the generation crank.
O/T, but the newer gen 60dV6 (2.8/3.1/3.4)cranks are good & solid to 7000RPM. and that is GM spec, which leaves much room above. yes, the condition of the bearings has great impact on this as well. I do beleive the internally balanced 88 crank is of the newer generation? no sure tho.
The rod and main bearings fail at high RPMs. Due to the junk bearings used from factory and most cheap replacements.
Not correct. The early 2.8's had inadequate lubrication of the bottom end bearings... that's why they fail.
quote
Originally posted by Pyrthian: depends on the generation crank.
O/T, but the newer gen 60dV6 (2.8/3.1/3.4)cranks are good & solid to 7000RPM. and that is GM spec, which leaves much room above. yes, the condition of the bearings has great impact on this as well. I do beleive the internally balanced 88 crank is of the newer generation? no sure tho.
Yes, the '88 (and I believe '87) cranks have the updated oil channels. Also, I think the later generation blocks have updated oil passages.
I bought my first Fiero, an '87 GT auto, with 170K on the clock. It spun a rod bearing the night I bought it as I executed a WOT freeway merge at the top of 2nd gear--IE, well within the design limits of the engine. For 6 or 7 years now I've owned a Formula. It's now pushing 160K and sees 6,000 RPM every time I drive it... no problems.
Maybe you should just put all your free monies into an engine upgrade worth while and stop pestering people with dumb questions, trying to brake the speed of sound with a 2.8.
Maybe you should just put all your free monies into an engine upgrade worth while and stop pestering people with dumb questions, trying to brake the speed of sound with a 2.8.
Is anyone taking bets on how many posts stewart will make it to?
The biggest thing I have found is the coil, when I swaped to DIS it pulls all the way to redline now.
FYI 85-87 RPM limit is 6012 in the ECM, 88's have no rev limit. So everyone who says they rev it higher than that either has an 88 ECM, their ECM reprogramed, or is just flat out lying. Mostly the later.
Not exactly.. There have been many discussions about this and the consensus is that not all pre 88s have no limiters.. I can tell you on my 87 GT which was bone stock at the time, I let a buddy drive it who took it to 6500 while I was screaming at him to shift. Luckily no damage from that stunt.
Originally posted by sardonyx247: FYI 85-87 RPM limit is 6012 in the ECM, 88's have no rev limit. So everyone who says they rev it higher than that either has an 88 ECM, their ECM reprogramed, or is just flat out lying. Mostly the later.
The 4th option is their tach is going bad and reading high. They very well may see 6500 rpm on the tach, but the engine is only actually spinning 6000 rpm. This would be an honest oversight.
As stated by by others, it dont pay to rev much above 4.5k without a better intake and headers.In which case you can take it to 7K as long as you also have good bearings and the internals are balanced for such.
With a Blazer distributor, and a carb, with ported everything and 1.6 rockers, mine pulls hard right up to 6200 rpm. It would go higher but I don't have the gonads to try it. I have an old friend who was an old time hydroplane racer (the hull still is in his yard) and he told me he used the marine version of the 2.8 racing. On a boat it will turn 8,000 rpm. A car is different so I expect 7,000 is about the limit.
Like others have said, with the stock intake and exhaust you will never get there.
Yes, the '88 (and I believe '87) cranks have the updated oil channels. Also, I think the later generation blocks have updated oil passages.
I bought my first Fiero, an '87 GT auto, with 170K on the clock. It spun a rod bearing the night I bought it as I executed a WOT freeway merge at the top of 2nd gear--IE, well within the design limits of the engine. For 6 or 7 years now I've owned a Formula. It's now pushing 160K and sees 6,000 RPM every time I drive it... no problems.
I heard that GM improved the oil passages on 88V6s, and the 3.4 V6 in Camaro's and Firebird's. (which many of us swap into our fieros for a upgraded improvement. I really would love to see photos of this that could supply proof on the location and spots of the improved oil channels. Its a good subject to shed light on. I'm very interested.
------------------ fierogt28
88 GT, Loaded, 5-speed. 88 GT, 5-speed. All original.
The biggest thing I have found is the coil, when I swaped to DIS it pulls all the way to redline now.
FYI 85-87 RPM limit is 6012 in the ECM, 88's have no rev limit. So everyone who says they rev it higher than that either has an 88 ECM, their ECM reprogramed, or is just flat out lying. Mostly the later.
Yeah, I want to get mine taken off!!! and good to know the rev limiter's rpm.
I have an '85 v6 im parting out because I ported everything on it. I can say it'll pull better because of what I did, but also because I upgraded the cam. and as far as the oiling issue, I had the GM 60* V6 race engine guide (I lost it, can anyone guide me to another?) and I used it to improve the oiling ability by opening up the galleys a bit. and I have clevite 77 bearings everywhere. so I'm good... (I think)
I got a new eagle crank for the 2.8 at a steal for 30 bucks, and I'll be putting that in sometime in the next month or so. I just wanted to build the engine for reliability (At any damn rpm I choose)
And like I said, I'm parting the 85's stuff out (intake, heads, exhaust) who said anything about me using stock components again? the post was about the mechanical limits of the 2.8. in any aspect one could provide from thier experience.
the stupidest question is the one not asked, right?
[This message has been edited by AL87 (edited 11-17-2012).]
You spent the last year worshipping the "Iron Duke" and trying to make it resemble a real engine..then gave up and sold off the parts.
Now the same thing for the 2.8
Reality Check! These are ancient cars with ancient performance stats. You can put lipstick on a pig- it is still a pig. Why rip apart, beat on it and then be disappointed? It is a cool looking economy car. That's it
A stock Fiero by today's standards is about as well performing as Grandpa's Ford Taurus. No amount of porting and polishingl, holley stickers, gasket matching, fancy scoops, performance chips and air intakes..will change that
With an engine swaps (and deep pockets or a lot of mechanical skills) you can make a Fiero into a sleeper. Otherwise, you are probably pissing in the wind and will still lose to my wife's Sienna minivan at the stoplights.
If you are going to rev a 25 year old motor to redline, it will blow up sooner or later.
Enjoy the 2.8 for what it is- a reasonably reliable cruising motor.. nothing to win races with
You spent the last year worshipping the "Iron Duke" and trying to make it resemble a real engine..then gave up and sold off the parts.
Now the same thing for the 2.8
Reality Check! These are ancient cars with ancient performance stats. You can put lipstick on a pig- it is still a pig. Why rip apart, beat on it and then be disappointed? It is a cool looking economy car. That's it
A stock Fiero by today's standards is about as well performing as Grandpa's Ford Taurus. No amount of porting and polishingl, holley stickers, gasket matching, fancy scoops, performance chips and air intakes..will change that
With an engine swaps (and deep pockets or a lot of mechanical skills) you can make a Fiero into a sleeper. Otherwise, you are probably pissing in the wind and will still lose to my wife's Sienna minivan at the stoplights.
If you are going to rev a 25 year old motor to redline, it will blow up sooner or later.
Enjoy the 2.8 for what it is- a reasonably reliable cruising motor.. nothing to win races with
Thank you! a 3100 and a cam might be worth something, but I wouldn't do anything less than a 3400/3500 or a 3800. it's just plain not worth it.
------------------ there's a Group on 60degreeV6.com for us 660 Fiero owners!
There are 3500's in Florida as low as $300. The whole swap could be done for $1000-1500 and have 50% more power than a stock 2.8 makes.... *WAY* better bang/buck ratio.
There are 3500's in Florida as low as $300. The whole swap could be done for $1000-1500 and have 50% more power than a stock 2.8 makes.... *WAY* better bang/buck ratio.
The biggest thing I have found is the coil, when I swaped to DIS it pulls all the way to redline now.
FYI 85-87 RPM limit is 6012 in the ECM, 88's have no rev limit. So everyone who says they rev it higher than that either has an 88 ECM, their ECM reprogramed, or is just flat out lying. Mostly the later.
quote
Originally posted by Boostdreamer:
Is an 88 ECM considered an upgrade for 85-86 V6's? I have an Auto Formula and an Auto 86 GT. Would that be a direct swap or should I change PROM's? I don't know one auto trans from the next.
I am wondering if the modifications to the engine had anything to do with removing the rev limiter. The 88s had better oil distribution on the mains, so maybe they decided higher RPMs were not a danger. If that is true, you would not want to remove the limit on the earlier engines. In either car, it's a waste of time to drive them over 5000 in stock form.
[This message has been edited by Gall757 (edited 11-19-2012).]
I've got what I've got, extra parts and NO cash. I hit the rpm limiter sometimes (looks to be over 6500) on my gauge) and nothing happens.
if anything if and when I run out of 2.8's to bolt in, I'll go over to a 3.4.
then either a 3800 S/C, or a V8 WHEN I HAVE THE MONEY.
My friend and I are swapping in a worked over 3800 S/C to put in his 88 formula.
Sell or swap the 2.8s on Craigslist, and then just pick up a 3.4 from a junkyard and then use your ported heads, intake and everything on that. You'd have a better, stronger lower end. Spend the 600 on forged pistons (I believe the rods are already forged but usually have some flash on them, correct me if I'm wrong(probably am)), then turbo the snot out of it. It'd be less time and cheaper than spending all that time on a 2.8, and while you're saving up the funds for the turbo you can still drive it NA with the stock ECU.
Sell or swap the 2.8s on Craigslist, and then just pick up a 3.4 from a junkyard and then use your ported heads, intake and everything on that. You'd have a better, stronger lower end. Spend the 600 on forged pistons (I believe the rods are already forged but usually have some flash on them, correct me if I'm wrong(probably am)), then turbo the snot out of it. It'd be less time and cheaper than spending all that time on a 2.8, and while you're saving up the funds for the turbo you can still drive it NA with the stock ECU.
do you guys realize that stock as cast 3400 heads outflow max effort portwork on the Gen 1 iron heads? do you also realize that a 3500 has heads that flow even better than the 3400 heads? do you also realize that both of those motors almost bolt in place of the stock 2.8?
------------------ there's a Group on 60degreeV6.com for us 660 Fiero owners!
do you guys realize that stock as cast 3400 heads outflow max effort portwork on the Gen 1 iron heads? do you also realize that a 3500 has heads that flow even better than the 3400 heads? do you also realize that both of those motors almost bolt in place of the stock 2.8?
I do, I was just stating that since he already stated he had all the parts for the top end.