Pennock's Fiero Forum
  Technical Discussion & Questions - Archive
  2.8 build ups

T H I S   I S   A N   A R C H I V E D   T O P I C
  

Email This Page to Someone! | Printable Version


2.8 build ups by Thegiz
Started on: 10-21-2007 12:14 PM
Replies: 16
Last post by: Blacktree on 10-23-2007 01:03 PM
Thegiz
Junior Member
Posts: 5
From: Forest Hill,MD,USA
Registered: Sep 2007


Feedback score: N/A
Leave feedback

Rate this member

Report this Post10-21-2007 12:14 PM Click Here to See the Profile for ThegizSend a Private Message to ThegizDirect Link to This Post
I have a 2.8 laying around and want to make as much power as possible with out NOS or turbo any help?
IP: Logged
PFF
System Bot
85FieroGT3.4
Member
Posts: 242
From: Lancaster, CA
Registered: May 2007


Feedback score: (1)
Leave feedback

Rate this member

Report this Post10-21-2007 12:41 PM Click Here to See the Profile for 85FieroGT3.4Send a Private Message to 85FieroGT3.4Direct Link to This Post

Ask people like Orief. He built a 3.4 that was carbed that produced 223hp at the wheels.

A short list of things to do are:
3400 TDC pistons on the pushrod (3.4 swap)
Crane 260 or 272 cam
Port and polish (can do at home if your carefull)
Port the exhaust manifolds
Shave the heads .020 if you want to spend the money
A more free flowing exhaust system
Either delete the cat or get a new, better flowing one
Change the intake (either a Truleo or Carb)
Change the exhaust manifolds (your choice - theres a couple)
Play with the timing to get the best setting
Remap the computer (go to certian people that are KNOWN, that way you don't waste your money or blow your motor)

Im sure that there are a few more tricks that someone could recomend. Keep in mind that certian mods require that you have to modify something else to support it in some way.

------------------

IP: Logged
mtownfiero
Member
Posts: 1779
From: Mansfield, Mass
Registered: Mar 2007


Feedback score:    (6)
Leave feedback

Rate this member

Report this Post10-21-2007 06:45 PM Click Here to See the Profile for mtownfieroSend a Private Message to mtownfieroDirect Link to This Post
When i save up the money im going to have mine stroked out to 3.1 with a bigger cam using the stock heads, headers and a different intake and in another thread i had it was said to put out around 190 hp to the wheels.
IP: Logged
goatnipples2002
Member
Posts: 2055
From: Bellevue,Ne.
Registered: Jul 2005


Feedback score: (1)
Leave feedback





Total ratings: 112
Rate this member

Report this Post10-22-2007 01:23 AM Click Here to See the Profile for goatnipples2002Click Here to visit goatnipples2002's HomePageSend a Private Message to goatnipples2002Direct Link to This Post
To eliminate confusion a 3400 and a TDC/DOHC 3.4 are NOT the same. (In case that's what you meant.)

Another option on the intake manifold is the "Enterprise".

The Comp and Crane 260s are weak. Try the crane 272 or the Crower lvl 5.

Ported Ex. manifolds are more bang for buck than headers any day.

DarthFiero at Sinister Performance for the chip burning (Yahoo! it).

Throw the 3.1 rotating assembly in there and/or have it balanced to the closest tolerances as possible so you can rev somewhat worry free.

Use some good bearings, head studs and get a good rotary file.
IP: Logged
85FieroGT3.4
Member
Posts: 242
From: Lancaster, CA
Registered: May 2007


Feedback score: (1)
Leave feedback

Rate this member

Report this Post10-22-2007 07:17 AM Click Here to See the Profile for 85FieroGT3.4Send a Private Message to 85FieroGT3.4Direct Link to This Post
 
quote
Originally posted by goatnipples2002:

To eliminate confusion a 3400 and a TDC/DOHC 3.4 are NOT the same. (In case that's what you meant.)


That is what I meant. Thanks. I am always doing that. I know that the 3400 is a rollerblock version of a Camaro 3.4(?) found in Grand Ams and such, and the TDC was found in Grand Prix GTPs back in the day, if Wikipedia told me right.
IP: Logged
JazzMan
Member
Posts: 18612
From:
Registered: Mar 2003


Feedback score:    (7)
Leave feedback





Total ratings: 653
User Banned

Report this Post10-22-2007 08:51 AM Click Here to See the Profile for JazzManSend a Private Message to JazzManDirect Link to This Post
Is the 3400 a 60° or 90° block?

JazzMan
IP: Logged
Oreif
Member
Posts: 16460
From: Schaumburg, IL
Registered: Jan 2000


Feedback score:    (19)
Leave feedback





Total ratings: 442
Rate this member

Report this Post10-22-2007 10:16 AM Click Here to See the Profile for OreifClick Here to visit Oreif's HomePageSend a Private Message to OreifDirect Link to This Post
 
quote
Originally posted by Thegiz:

I have a 2.8 laying around and want to make as much power as possible with out NOS or turbo any help?


Removed the 3.1L stroke kit. It will be lower comprassion.
Crane 272 cam
Comp Cams 1.5 roller tipped rockers, high-perf lifters, and heavy duty pushrods
Coyles double roller timing chain
Port/polish and shave the heads (shave .010 for an increased compression of 9.4:1)
Trueleo Intake and exhaust headers (use 2.5" pipes)
Accel 19# injectors
Holley adjustable fuel pressure regulator
60mm - 62mm throttle body
MSD or Crane Fireball ignition system
Dyno tune the engine

This should get you around 200-210hp at the crank
------------------

Happiness isn't around the corner...
Happiness IS the corner.

ZZ4 Powered !!

[This message has been edited by Oreif (edited 10-22-2007).]

IP: Logged
Blacktree
Member
Posts: 20770
From: Central Florida
Registered: Dec 2001


Feedback score:    (12)
Leave feedback





Total ratings: 350
Rate this member

Report this Post10-22-2007 01:57 PM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageSend a Private Message to BlacktreeDirect Link to This Post
 
quote
Originally posted by Oreif: Port/polish and shave the heads (shave .010 for an increased compression of 9.4:1)

That's not how it worked out with my 3.1 stroker engine. With the stock Fiero heads and block, and the 3.1 rotating assembly, I would've had an 8.3:1 compression ratio. No, that's not a typo. I ended up shaving 0.015" off the block and 0.010" off the heads just get the compression back up to 8.9:1. After that, I ended up having to shave 0.015" off the lower intake, to make it fit.

Keep in mind that there are no flat-top pistons available for the 3.1. The only 2 types available are 12cc dish (for iron heads) or 26cc dish (for aluminum heads). So when you install them into a 2.8, the compression ratio is going to drop. Hence all the block/head shaving.
IP: Logged
Arns85GT
Member
Posts: 11159
From: London, Ontario, Canada
Registered: Jul 2003


Feedback score: (1)
Leave feedback





Total ratings: 202
Rate this member

Report this Post10-22-2007 05:22 PM Click Here to See the Profile for Arns85GTSend a Private Message to Arns85GTDirect Link to This Post
 
quote
Originally posted by Thegiz:

I have a 2.8 laying around and want to make as much power as possible with out NOS or turbo any help?


OK, 2.8, not 3.1, or 3.4.

Pretty much what Oreif described. I have a rebuilt on the stand right now. It will get ported heads (off my current 2.8) a Crane 2030 cam with 1.6 roller tip rockers, Cloyes timing set with 4* advance (to bump up the low end. Crane tells me torque will kick in at 1,000 rpm), long tube headers into true duals, (33" primaries), Holley 8007 4 barrel over the Edelbrock intake. It will be operating with auxilliary cooling and going into a Bully Stage II clutch (sintered iron)

My current 2.8 is running stock with the ported heads and the carb and makes 132 rwhp on the dyno with tired rings and only 125 compression. I am aiming for a realistic 175 at the crank for the new motor. I really don't want more with the 2.8 because I want a nice streetable engine with decent gas mileage.

If you want to boost it up more, you'll be going to high compression pistons, SBC connecting rods.

Hope this helps

------------------

IP: Logged
Oreif
Member
Posts: 16460
From: Schaumburg, IL
Registered: Jan 2000


Feedback score:    (19)
Leave feedback





Total ratings: 442
Rate this member

Report this Post10-22-2007 05:45 PM Click Here to See the Profile for OreifClick Here to visit Oreif's HomePageSend a Private Message to OreifDirect Link to This Post
 
quote
Originally posted by Blacktree:

That's not how it worked out with my 3.1 stroker engine. With the stock Fiero heads and block, and the 3.1 rotating assembly, I would've had an 8.3:1 compression ratio. No, that's not a typo. I ended up shaving 0.015" off the block and 0.010" off the heads just get the compression back up to 8.9:1. After that, I ended up having to shave 0.015" off the lower intake, to make it fit.



WOW, I just checked it out and the compression ratio for the 3.1L with iron heads is 8.2:1 !!
I didn't know that the 3.1L was a lower compression motor and only 120hp in the minivans.
Thanks for the info.

I corrected the above to remove the 3.1L stroker kit. If you want to go to 3.1L I would recommend custom pistons to get the compression up to 9.5:1 or better. (10.5:1 would be ideal actually)

IP: Logged
Oreif
Member
Posts: 16460
From: Schaumburg, IL
Registered: Jan 2000


Feedback score:    (19)
Leave feedback





Total ratings: 442
Rate this member

Report this Post10-22-2007 05:48 PM Click Here to See the Profile for OreifClick Here to visit Oreif's HomePageSend a Private Message to OreifDirect Link to This Post

Oreif

16460 posts
Member since Jan 2000
 
quote
Originally posted by Arns85GT:


I have a rebuilt on the stand right now. It will get ported heads (off my current 2.8) a Crane 2030 cam with 1.6 roller tip rockers, Cloyes timing set with 4* advance (to bump up the low end. Crane tells me torque will kick in at 1,000 rpm), long tube headers into true duals, (33" primaries), Holley 8007 4 barrel over the Edelbrock intake. It will be operating with auxilliary cooling and going into a Bully Stage II clutch (sintered iron)




If you are going to carb the motor, the H260 would be a better choice. The dual-pattern cams work so much better with a carb than the single pattern cams like the 2030.
IP: Logged
PFF
System Bot
Blacktree
Member
Posts: 20770
From: Central Florida
Registered: Dec 2001


Feedback score:    (12)
Leave feedback





Total ratings: 350
Rate this member

Report this Post10-22-2007 06:36 PM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageSend a Private Message to BlacktreeDirect Link to This Post
 
quote
Originally posted by Oreif: Thanks for the info.

No problem

Unfortunately, I had to find that out the hard way. I had already purchased the 3.1 conversion parts (and partially assembled the short block) before I found out that nasty little secret. You can imagine my surprise when the number "8.3" came up on my calculator. If I could do it over again, I'd either build a high-compression 2.8 (or a destroked 3.4) with a lumpy cam and upgraded intake.
IP: Logged
Arns85GT
Member
Posts: 11159
From: London, Ontario, Canada
Registered: Jul 2003


Feedback score: (1)
Leave feedback





Total ratings: 202
Rate this member

Report this Post10-22-2007 09:46 PM Click Here to See the Profile for Arns85GTSend a Private Message to Arns85GTDirect Link to This Post
 
quote
Originally posted by Oreif:


If you are going to carb the motor, the H260 would be a better choice. The dual-pattern cams work so much better with a carb than the single pattern cams like the 2030.


The rebuild came with the 2030 and when I called Crane and told them about the 1.6 roller tips and advancing the cam timing, they gave the thumbs up. They advised me that the 1.6's on a 2030 makes it approximately the same as the H260. Call me cheap, I'm not about to buy a new one, but thanks for the word.

Arn
IP: Logged
goatnipples2002
Member
Posts: 2055
From: Bellevue,Ne.
Registered: Jul 2005


Feedback score: (1)
Leave feedback





Total ratings: 112
Rate this member

Report this Post10-23-2007 02:28 AM Click Here to See the Profile for goatnipples2002Click Here to visit goatnipples2002's HomePageSend a Private Message to goatnipples2002Direct Link to This Post
You could run the AL heads from a 3400. You would need to modify the UIM.

[This message has been edited by goatnipples2002 (edited 10-23-2007).]

IP: Logged
Oreif
Member
Posts: 16460
From: Schaumburg, IL
Registered: Jan 2000


Feedback score:    (19)
Leave feedback





Total ratings: 442
Rate this member

Report this Post10-23-2007 06:33 AM Click Here to See the Profile for OreifClick Here to visit Oreif's HomePageSend a Private Message to OreifDirect Link to This Post
 
quote
Originally posted by Arns85GT:


They advised me that the 1.6's on a 2030 makes it approximately the same as the H260.

Arn


That is not quite right. Yes the intake lift is about the same but the exhaust lift is different. Which is what makes the H260 a dual-pattern cam. This allows the carb to run a higher and wider power band. The low to mid-range RPM's will feel weak when using a single pattern cam and a carb. The only reason I suggest changing out the cam, Is I wouldn't want you to spend the time and money to build it up and then have the disappointment of lackluster power.
IP: Logged
Arns85GT
Member
Posts: 11159
From: London, Ontario, Canada
Registered: Jul 2003


Feedback score: (1)
Leave feedback





Total ratings: 202
Rate this member

Report this Post10-23-2007 09:28 AM Click Here to See the Profile for Arns85GTSend a Private Message to Arns85GTDirect Link to This Post
Understood. And thanks for the good thought. While if I was buying the cam I'd probably have bought the H260 but, I got the whole rebuilt engine for the price of the cam. The slight difference is 204* intake/214* exhaust vs. 204* intake/216* exhaust. The 2 degrees when compared to the cost to replace it just wasn't worth it to me. (money is an object ) The engine will have a tuned long tube true dual system. I did the calculations and it came out to 33" with this cam. So far as I know, nobody has done up 33" headers for the 2.8 here on the forum, and I think the extraction factor will definitely improve the exhaust pull for either cam.

It should be a good build and the dyno will be interesting. BTW, I am doing 4* of advance which will put me at 208*intake/210*exhaust. Another curve.

Arn

typo

[This message has been edited by Arns85GT (edited 10-23-2007).]

IP: Logged
Blacktree
Member
Posts: 20770
From: Central Florida
Registered: Dec 2001


Feedback score:    (12)
Leave feedback





Total ratings: 350
Rate this member

Report this Post10-23-2007 01:03 PM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageSend a Private Message to BlacktreeDirect Link to This Post
 
quote
Originally posted by Oreif: WOW, I just checked it out and the compression ratio for the 3.1L with iron heads is 8.2:1 !!

Just a thought: the 3.1 would be a great candidate for a turbo. I've been toying with the idea myself... not sure if I'll actually do it, though.
IP: Logged



All times are ET (US)

T H I S   I S   A N   A R C H I V E D   T O P I C
  

Contact Us | Back To Main Page

Advertizing on PFF | Fiero Parts Vendors
PFF Merchandise | Fiero Gallery | Ogre's Cave
Real-Time Chat | Fiero Related Auctions on eBay



Copyright (c) 1999, C. Pennock