PFF - Pennock's Fiero Forum, PDA Edition

Returning Fiero Owner - Let's Talk 2.8 Breathing (Page 7/14)

sourmash

APR 07, 12:05 PM

quote

Originally posted by ericjon262:

Failure rate is a really hard metric to use for something like a turbo. I say this because people will tend to attribute failure to the product, when the problem could very well stem from a piss poor installation. too much oil, not enough, not installed level or with a proper drain, improperly sized for the application ect. that's not to say they don't fail due to material defect or workmanship, but the big picture isn't always as clear as we would like it to be. Couple that with the fact that the majority of people purchasing these Chinese turbos are likely younger, less experienced individuals who may not know what is required, or what correct looks like.

None of that is a valid argument to disprove my statement when speaking of like for like owners of like for like cars. I specifically didn't state the same failure rate for ebay Borg Waners, Garrett, HKS, Holset for the same make of car because the failure rate is not as high or fast for those examples based on what I've witnessed posted on specific forums. Like for like owners of like for like model of car I've seen have reported higher and faster failure rates of ebay Chinese turbos than the others. Where you have pairs of turbos being bought and used, it's not uncommon for one to underperform the other and/or fail quickly while the other won't have an issue. With the Audi I mentioned you have to pull the engine to replace turbos so you hear about this because it hurts more than with other makes.

ericjon262

APR 07, 02:16 PM

quote

Originally posted by sourmash:
None of that is a valid argument to disprove my statement when speaking of like for like owners of like for like cars. I specifically didn't state the same failure rate for ebay Borg Waners, Garrett, HKS, Holset for the same make of car because the failure rate is not as high or fast for those examples based on what I've witnessed posted on specific forums. Like for like owners of like for like model of car I've seen have reported higher and faster failure rates of ebay Chinese turbos than the others. Where you have pairs of turbos being bought and used, it's not uncommon for one to underperform the other and/or fail quickly while the other won't have an issue. With the Audi I mentioned you have to pull the engine to replace turbos so you hear about this because it hurts more than with other makes.

That wasn't meant to say they are a 0 failure rate, and gods gift to man, more to say that statistics don't always tell the whole story.

------------------
"I am not what you so glibly call to be a civilized man. I have broken with society for reasons which I alone am able to appreciate. I am therefore not subject to it's stupid laws, and I ask you to never allude to them in my presence again."

cognita semper

http://www.fiero.nl/forum/Forum2/HTML/119122.html

sourmash

APR 07, 03:49 PM

I understand. So do you believe the ebay Chinese turbos don't have a higher and/or faster failure rate than the brands mentioned in this thread?

ericjon262

APR 07, 10:07 PM

quote

Originally posted by sourmash:

I understand. So do you believe the ebay Chinese turbos don't have a higher and/or faster failure rate than the brands mentioned in this thread?

I wouldn't say that. I believe that the quality of the installation of said turbos is frequently "just send it" and when a failure occurs the "made in china POS" turbo is blamed regardless of whether it was the root cause of the failure or not. this leads the failure numbers to be inflated higher than the failure due to the turbo being low quality, which makes the difference between the "name brand" and china turbo seem larger than it is.

I also think that people love to complain, so when a failure occurs, you're more likely to hear about it, than a success.

TL;DR,

failure Due to quatity + failure due to crappy install > just failure due to quality > name brand failures (but not by as much as people think)

that's my thoughts, I may be right, I may be wrong, but do you understand what I mean?

sourmash

APR 08, 04:51 PM

I do understand what you're saying and I'm not totally discounting it. On the flip side there is also dynamic where buyers don't like to admit that despite warnings they bought anyway and experienced the specific problem. Some people do like to complain and of course shift blame and there are people who won't admit a mistake to the point of defending their decision and the supplier.

BillS

APR 10, 02:21 PM

quote

Originally posted by La fiera:

So the 3.4 and 2.8 have different deck heights?

No, the same. The block is able to take the larger bore and the compression height on the pistons is adjusted for the longer stroke.

On my turbo engine in the Fiero I had to use a short (Fiero) stroke crank because the 3.4 was brand new and no parts were out there yet. On the Jamaican I used a 3.4 engine so no issues.

The longer stroke gets you to 3.1 and adds some very welcome mid range torque and the larger bore added on the 3.4 gets you the extra 0.3 liters.

jjd2296

APR 10, 02:53 PM

SpaceLion

APR 10, 05:29 PM

Part/Service for sale?

quote

Originally posted by jjd2296:

cvxjet

APR 10, 06:03 PM

I wanted to state in here that MORE is not always better; I grew up a "Ford man" and found out back in the mid-70s about the 351 Cleveland situation. Ford made the heads "Ready for Trans Am racing"- Gigantic ports and valves....But the problem was they did not flow well at low RPM- the fuel-air mixture would STAGNATE and separate before reaching the combustion chamber.....I remember riding in a friend's Cougar.....Floor it and nothing would happen for a few seconds- the engine barely pulling...then as it reached 3000 rpm, it would start to pull stronger and stronger. It is better to MATCH the flow of your heads and intake to the RPM capability of your engine- not TOP RPM but the RPM BAND in Total.

(Note; There were two Cleveland heads; 2-Barrel for engines with 2 barrel Carburetors and 4-Barrel Heads for use in performance applications with 4 barrel carburetors; They are actually labeled as 2V and 4V- but they are both TWO valve Pushrod heads)

Two things about those Cleveland heads; A) The 2 barrel heads flowed less- it was well-known that, everything else being equal (Trany, axle ratio and vehicle weight), the 2 barrel engine would beat the 4 barrel engine out of the hole by a couple of car lengths.....The 4 barrel would start catching up towards the end of the quarter.

B) Believe it or not, the 4 barrel (Two VALVE) Cleveland heads (circa 1970) flow better on the intake side than the new Coyote V8 4 VALVE heads! (The exhaust side sucks because of the packaging problems created by (1st gen) Mustang spring towers- The exhaust had to do a 90 degree turn down)

[This message has been edited by cvxjet (edited 04-10-2020).]

olejoedad

APR 10, 06:17 PM

Ford used the 'V' designator for venturi....2 V was two venturis, 4 V was four venturis.....rather than the two barrel and four barrel.....