PFF - Pennock's Fiero Forum, PDA Edition

Returning Fiero Owner - Let's Talk 2.8 Breathing (Page 6/14)

BillS

APR 06, 04:30 PM

quote

Originally posted by La fiera:

That intake is a choker bill! Beautiful car tough!

IIRC the F body intake flows significantly better than the necked down Fiero intake, but not as well as the Truleo, nor probably than a reworked Fiero with added volume. Anyone know of a thread with the various flow stats?

The F body intake, reworked internally and bored out for the 62 mm TB completely cured the throttled chicken act the stock engine does when you ask it to rev a bit. For the record, a similarly relieved stock Fiero intake with a turbo also flows, but that is mostly the turbo.

Had I really wanted much better flow I would have gone with an alloy head engine, but IIRC they are slightly taller and my engine height was critical - to put this body on the MG chassis, they cut down the firewall and ditched the heater because it wouldn't fit. That left very little room over a V6 engine for a flat hood without a scoop. We had to drop the engine as low as we could just to get it under that hood.

Does anyone recall the engine heights on a 2.8 vs. the F body 3.4? (It's been almost 15 years since I did the Jamaican and I don't recall the measurements).

BTW, getting the Fiero valve covers on a 3.4 is a bit of a ***** - they foul the underside of the intake manifold but only just so they need to be clearanced.

lordfiero

APR 06, 04:55 PM

Those camaro intakes flows equal to the fiero intake when measured on individual runners.

La fiera

APR 06, 06:28 PM

quote

Originally posted by BillS:

Does anyone recall the engine heights on a 2.8 vs. the F body 3.4? (It's been almost 15 years since I did the Jamaican and I don't recall the measurements).

BTW, getting the Fiero valve covers on a 3.4 is a bit of a ***** - they foul the underside of the intake manifold but only just so they need to be clearanced.

So the 3.4 and 2.8 have differerent deck heights?

sourmash

APR 06, 08:37 PM

quote

Originally posted by Dennis LaGrua:

Possibly so but porting will never get you anywhere near as much air into the engine than as a Turbo. If you are concerned about Chinese turbo quality then a good used Garrett, HKS, or Holset may be the ticket.

I didn' t say don't go turbo. It's the ebay Chinese turbos I warned about, yes, those super cheapies. And gobs of wheels are made in some part of Asia, even the ones I bought new. And I wouldn't have any major concerns about a used turbo, or rebuilding one of those you mentioned. One in my garage is from a 300ZX, a T3 with oiled and watered center section I'd like to build into a T3/T4 hybrid for something.
The only new turbos I ever bought were 800 apiece for a new Frankenturbos for an Audi. The wheels were made in Malaysia I think so it's not the Asian thing I'm saying. And there are other Asian/Chinese parts but the competent assembly of them is what pays off. That's what I paid for when I bought those, but there's Asian parts in them. Do the homework and don't let the price decide for you. If you buy the ebay Chinese cheapie and aren't going to use it/them right away (warranty lost, IOWs) find someone who knows how to check it/them over.

You don't have to pay 800 each like I did. But an Audi 2.7tt is about a 27 hr job, so...that makes a difference in choosing. The Borg=Warners didn't make sense at the time. Too much.

[This message has been edited by sourmash (edited 04-06-2020).]

sourmash

APR 06, 09:02 PM

quote

Originally posted by ericjon262:

it's worth mentioning to, that there are plenty of people making big power on the Chinese turbos, and have been for a long time. it's also worth mentioning that in some instances, you can buy 2 or 3 of them for the price of say, a precision 6266.

Ok, that's excellent. So which ones do you recommend then? A link to ones you have confidence in would be very helpful.

pmbrunelle

APR 06, 09:25 PM

quote

If you do that, it would be worth anticipating the possibility of the Chinese turbos not working out, and throwing the towel and getting a genuine "name-brand" unit.

So you would want to check that a name-brand turbo exists in the same physical form factor (frame size, compressor inlet/outlet diameters, turbine flanges, oil and water connection positions, etc).

If the name-brand turbo doesn't have the exact same form factor, you're going to be wasting money redoing plumbing and re-fitting it in the engine bay.

I started with an ebay T3 0.63 A/R turbine housing... when I got a genuine Mexican Garrett with an ATP turbine housing (also T3 0.63 A/R), I found that the turbine housings were dimensionally different, despite being nominally "the same".

It wouldn't have been possible to change from one turbo style to another without a bunch of rework.

ericjon262

APR 07, 01:11 AM

quote

Originally posted by sourmash:

Ok, that's excellent. So which ones do you recommend then? A link to ones you have confidence in would be very helpful.

a ton of people swear by VS racing, I was very tempted to go with one, I could have bought two of them for the price of my precision 6266.

https://turbo4less.com/prod...ing/turbos-vsracing/

That being said, PM Brunelle's recommendation is a very good one. make sure you get something that you can buy again, or a bolt in replacement of, I made this mistake a few years ago and went through hell finding a replacement.

------------------
"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, 07:08 AM

Which the same can be said for my original post about the ebay Chinese turbos and to keep the much higher and faster failure rate in mind (when making your choice).

La fiera

APR 07, 11:20 AM

quote

Originally posted by La fiera:

So the 3.4 and 2.8 have differerent deck heights?

Research shows they have the same 224mm Deck Height.

ericjon262

APR 07, 11:37 AM

quote

Originally posted by sourmash:

Which the same can be said for my original post about the ebay Chinese turbos and to keep the much higher and faster failure rate in mind (when making your choice).

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.

quote

Originally posted by La fiera:

Research shows they have the same 224mm Deck Height.

all pushrod 60 degree V6 passenger car(and S series truck/SUV) engines have the same deck height, up to the LX9 3500. this includes the 3.4 twin dual cam engines, but does not include the High Feature line (3.6 DOHC engines) or the GMC 60V6 of the 60's. I believe the High Value line (VCT engines,3900, LZ4 3500 ect.) also have the same deck height, but I haven't verified that myself.