2.2 JTS Big Bore Project? - Alfa Romeo Forum
You are currently unregistered, register for more features.    
Tuning & Upgrades Discuss performance enhancements for your Alfa Romeo

 
Thread Tools
(Post Link) post #1 of 20 Old 19-12-13 Thread Starter
Status: Not Stock
AO Member
 
Join Date: Mar 2010
Location: Singapore
County: -
Posts: 853
2.2 JTS Big Bore Project?

Ok I've got a 159 2.2 JTS which we're thinking of increasing its capacity.

Either through a bigger bore and/or change in piston length + Port & Polish.

Any idea if anyone here has done this or where do we start?
Saabretooth is offline  
Sponsored Links
Advertisement
 
dc
Status: -
AO Silver Member
 
dc's Avatar
 
Join Date: Feb 2002
Location: United Kingdom
County: Hertfordshire
Posts: 1,064

Member car:

Brera 2.2 JTS

I would be interested to hear what can be done to this engine, particularly the port and polish..
dc is offline  
(Post Link) post #3 of 20 Old 20-12-13 Thread Starter
Status: Not Stock
AO Member
 
Join Date: Mar 2010
Location: Singapore
County: -
Posts: 853
The reasons for doing this is 2 fold.

1) to keep the car NA

2) TC and SC make it too obvious for the local authorities who do not like these add-ons to the car.
Saabretooth is offline  
(Post Link) post #4 of 20 Old 20-12-13 Thread Starter
Status: Not Stock
AO Member
 
Join Date: Mar 2010
Location: Singapore
County: -
Posts: 853
Also in the works are

1) De-cat or Sports cat in the manifold

2) Walbro Fuel Pump if required, to keep and have high levels of fuel pressure

3) Maybe a change of cams

All these, on top of the port & polish and larger bore, lighter pistons, crank...etc

finished up with a proper tune, raised rpm and speed delimited.
Saabretooth is offline  
Status: Race cars in progress
AO Silver Member
 
Gertie's Avatar
 
Join Date: Oct 2007
Location: South Africa
County: Gauteng
Posts: 5,993
Garage
Quote:
Originally Posted by Saabretooth View Post
Ok I've got a 159 2.2 JTS which we're thinking of increasing its capacity.

Either through a bigger bore and/or change in piston length + Port & Polish.
Any idea if anyone here has done this or where do we start?
Remember that engine volume is defined as swept stroke x area of bore. By adjusting conrod length or piston height does not influence swept stroke - it changes the compression ratio only. Stroking by definition means to lengthen the crankshaft. Increasing the piston bore does relate in increasing capacity.

By increasing compression ratio - you increase the thermal efficiency of the fuel burn thus better power for each cc of fuel used The problem comes in with pre-detonation (a.k.a) pinging (a.k.a) knocking.

By Flowing the input ports you increase the air velocity that the air/fuel can enter the combustion chamber, thus increasing potential power. By Flowing the exhaust ports, you increase the air velocity of exhaust gasses leaving the combustion chamber, thus leaving a cleaner environment for the new air/fuel to burn.

Now increased air velocity only helps a small bit to get more air/fuel in. By getting more aggressive cams you lengthen the time to port stays open to let more air/fuel in. With Inlet / outlet cam overlap you allow the new air/fuel to push out the old exhaust - but overdoing that allows unburnt air/fuel to go into the exhaust and increases fuel consumption more than the power it adds. By increasing the valve size you increase the volume of air that can enter for a certain valve duration - it speaks for itself, but difficult to adjust

So if you can increase all 3 air characteristics - air velocity (port flowing) - valve open time (cams) and valve open area (bigger valves) you will optimize quite a bit.

Now Back to CR and capacity... If you have poor flow as defined above, increased capacity will not help much as you are not getting optimum air/fuel in... Higher CR will always increase thermal efficiency, but by not adjusting any of the other items - it in itself does not add that much to warrant opening the engine...

Last edited by Gertie; 20-12-13 at 14:02.
Gertie is offline  
Status: Race cars in progress
AO Silver Member
 
Gertie's Avatar
 
Join Date: Oct 2007
Location: South Africa
County: Gauteng
Posts: 5,993
Garage
Quote:
Originally Posted by Saabretooth View Post
1) De-cat or Sports cat in the manifold
Will help a lot with exhaust gas velocity DO IT!
Quote:
Originally Posted by Saabretooth View Post
2) Walbro Fuel Pump if required, to keep and have high levels of fuel pressure
This is needed if mapping alone does not add enough fuel to mixture (if it leans out) - really only a turbo problem N/A should be able to keep up
Quote:
Originally Posted by Saabretooth View Post
3) Maybe a change of cams
Should be one of your highest priorities in increased power It is relatively easy to do - You only need to open cam cover, not head off...
Quote:
Originally Posted by Saabretooth View Post
All these, on top of the port & polish and larger bore, lighter pistons, crank...etc
Lighter only adds rev-ability... how quickly the engine can accelerate, it will not add to HP figure. But that is needed when power is up and the car is used in quick accelerations conditions - racing.
Quote:
Originally Posted by Saabretooth View Post
finished up with a proper tune, raised rpm and speed delimited.
Proper tune is mandatory to make the changes "come alive", otherwise they will not help all that much alone... Rasied RPM will add HP figure IF there is power in the high RPMs - that means cams need to be aggressive and air flow need to be fast

Last edited by Gertie; 20-12-13 at 14:06.
Gertie is offline  
(Post Link) post #7 of 20 Old 20-12-13 Thread Starter
Status: Not Stock
AO Member
 
Join Date: Mar 2010
Location: Singapore
County: -
Posts: 853
Thank you Gertie!

Next set of important questions.

Where do I get the

1) Cams (custom, not C&B if possible)
2) Pistons
3) Crank (if needed)
4) supporting parts such as gaskets ...etc etc etc..... and what size is most suitable for this block?

I am thinking to do a 2400cc volume and what sizing of bore would be suggested?

Thanks
Saabretooth is offline  
Status: -
AO Member
 
Alecci's Avatar
 
Join Date: Dec 2013
Location: Sweden
County: -
Posts: 23
Hi,

Crower in the US can do custom crankshafts, connecting rods and camshafts.

Wssner in Germany can do custom pistons and connecting rods.

I also think that Pankl can do custom pistons (under brand CP) and connecting rods (under brand Carillo).
Alecci is offline  
Status: -
AO Silver Member
 
Join Date: Nov 2013
Location: United Kingdom
County: Carmarthenshire
Posts: 3,990

Member car:

Alfa 156 Gta

piper and kent in the uk will do custom cams

catcams.com do custom cams and i believe conrods as well WELCOME | CAT CAMS performance camshafts

Wossner or mahle for pistons MAHLE Group | Forged pistons

arrow engineering do rods and cranks Arrow Precision

and i have used farndon for steel crankshafts Farndon - World class racing, OEM crankshaft and engine component manufacturer
maxiboy wales is offline  
(Post Link) post #10 of 20 Old 28-12-13 Thread Starter
Status: Not Stock
AO Member
 
Join Date: Mar 2010
Location: Singapore
County: -
Posts: 853
Thanks guys.
Let me do some homework and see how I can piece all these together.

Want to figure out whats the safest big bore size I can work on. 2400cc?
Saabretooth is offline  
Status: Alfaless!!
AO Silver Member
 
phil-gtv6's Avatar
 
Join Date: Aug 2006
Location: United Kingdom
County: West Sussex
Posts: 3,090
Garage

Member car:

E82 125i

Apart from the bigger bore, all work has been done on this one, giving 220bhp (not sure you'll need that many exhuasts though!

From comments:
"Orque equidistant racing manifold with 68mm central and CSC rear. Grind original camshaft and cylinder head, big valve; forging piston with ECU reprogramming, itg carbon direct intake system. "

http://m.youtube.com/watch?v=O33isSwroTE
phil-gtv6 is offline  
Status: Waiting for Stelvio QV
AO Platinum Member
 
OperationAlfa's Avatar
 
Join Date: May 2007
Location: United Kingdom
County: Essex
Posts: 23,452
The standard fuel pump will be more than capable for what you are looking at doing.
OperationAlfa is offline  
(Post Link) post #13 of 20 Old 31-12-13 Thread Starter
Status: Not Stock
AO Member
 
Join Date: Mar 2010
Location: Singapore
County: -
Posts: 853
I've visited Mario in Taiwan before. Nice chap and very helpful.

He's got a very nicely sorted SZ he uses for racing.

I'm not sure what I can order from him for the stuff, and the specs needed to bore the engine, and the headwork too.
He doesn't do too many 2.2s as there are not that many in Taiwan
Saabretooth is offline  
Status: fix it till it's broken
AO Member
 
Black-Sheep's Avatar
 
Join Date: Jul 2008
Location: Germany
County: Sachsen
Posts: 562

Member car:

Delta III 1.9 TT

Watch out highly tuned N/A Cars from Japan - there fuel is 110 octane i belive so they can run a much more aggressive compression and ignite the mix much later than we can in europe with 98 or 100 Octane.

Anyway i think the 2.2 JTS seems to be a pretty damn good NA Engine (looking at the stock output) - only problem with it beeing the heavy cars it hast to move - a light MX5 or even Alfa 147 would be pretty fast with the stock 185 HP....

in other words - DO it - and do it right!
Black-Sheep is offline  
(Post Link) post #15 of 20 Old 05-01-14 Thread Starter
Status: Not Stock
AO Member
 
Join Date: Mar 2010
Location: Singapore
County: -
Posts: 853
That's the plan.

We get 98 RON here at best.

If we want to run more advanced timing, we might use a WMI kit.
Saabretooth is offline  
Status: playing kill by numbers
AO Gold Member
 
Join Date: Feb 2005
Location: Belgium
County: Down in the Park
Posts: 8,786
Quote:
Originally Posted by Black-Sheep View Post
Watch out highly tuned N/A Cars from Japan - there fuel is 110 octane i belive so they can run a much more aggressive compression and ignite the mix much later than we can in europe with 98 or 100 Octane.

Anyway i think the 2.2 JTS seems to be a pretty damn good NA Engine (looking at the stock output) - only problem with it beeing the heavy cars it hast to move - a light MX5 or even Alfa 147 would be pretty fast with the stock 185 HP....

in other words - DO it - and do it right!

you mean ignite much earlier. the problem with low octane fuel and a lot of ignition advance is that the flame front isn't exactly a flame front moving away from the spark plug but beacuse of the rising pressure and temperature several other flame fronts emerge. You pretty much end up with a diesel engine. the whol lot burns way too fast and might even be finished before the piston reaches TDC, resulting in knocking and if severe enough a holed piston...

Waiting longer to ignite ensures that the piston is well on it's way down by the time pressure starts to rise and this stops the fuel from igniting by itself disturbing the flame front.
Cuore_Sportivo_155 is offline  
Status: Race cars in progress
AO Silver Member
 
Gertie's Avatar
 
Join Date: Oct 2007
Location: South Africa
County: Gauteng
Posts: 5,993
Garage
Quote:
Originally Posted by Saabretooth View Post
That's the plan.

We get 98 RON here at best.

If we want to run more advanced timing, we might use a WMI kit.
Yes WMI is a good anti-detonation device - The only problem (rather read challenge) in an N/A car - once you've committed to high CR, WMI and "lower octane" fuel - you have to run WMI ALL THE TIME (turbo cars only spray when in boost) And be sure you have decent knock detection with auto retarding when something goes wrong with the WMI (like WM mixture runs out or something like that) - In a Forced Induction car that has knock detection and boost control one could chose to pull the boost back or timing or a bit of both...
Gertie is offline  
(Post Link) post #18 of 20 Old 05-01-14 Thread Starter
Status: Not Stock
AO Member
 
Join Date: Mar 2010
Location: Singapore
County: -
Posts: 853
Here's the idea on the plate at the moment:


Option 1)
We're going to set up the tuning with high compression without the WMI kit first, and then install the kit thereafter, doesn't maximize the WMI kit, but it does keep the engine cooler under crazy load

Option 2)
Tune the car with WMI kit, but using water only, so that we do not advance the engine too much. Its not a FI engine, so we're looking to keep the car cool for longevity.




In both cases, even if the water runs out, the engine retards back to a safe level and still have decent performance.
Saabretooth is offline  
Status: fix it till it's broken
AO Member
 
Black-Sheep's Avatar
 
Join Date: Jul 2008
Location: Germany
County: Sachsen
Posts: 562

Member car:

Delta III 1.9 TT

Quote:
Originally Posted by Cuore_Sportivo_155 View Post
you mean ignite much earlier

jep - you got me there

@Saabretooth

keep us posted
Black-Sheep is offline  
(Post Link) post #20 of 20 Old 16-01-14 Thread Starter
Status: Not Stock
AO Member
 
Join Date: Mar 2010
Location: Singapore
County: -
Posts: 853
After consultations with the owner, we're going to work with Japan Cams, Decat Manifold first, among some of the easier to do stuff. and have a run with the car to see if it makes the power he's looking for.

If not, we will revisit the big bore project.

If we do get to the big bore (which I think its at best a 2.4 or 2.5l capacity) I'll be back here.
Saabretooth is offline  
Reply

Go Back   Alfa Romeo Forum > Supported Alfa Romeo Models > Technical & Vehicle Assistance > Tuning & Upgrades

Tags
big , bore , jts , project

Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

 
For the best viewing experience please update your browser to Google Chrome