pistons and supercharging

[66Sprint6]

If I were, and this is a BIG if, to supercharge my 66 200 with an Eaton M90, what should I do to the motor to be able to handle this, such as pistons etc.????? WOuld the stock ones be ok, maybe 2.3liter flat tops?? Also, what else would have to be done to the motor to be able to handle the supercharger???
Matt

 

[Anlushac11]

8)

With a forced induction engine, there are those that say you can get by with cast pistons.

Ford put forged pistons even in the 79-82 2.3L turbo motors with 6 lbs boost.

Running forced induction, if you have a lean condtion occur, or detonation you have no margin of error and really bad things happen. Holes in side of block type bad.

I want to build my 200 so that I can turbo it later.

I want forged pistons, ARP rod and main bolts and that is about all you need. You can take oil for turbo by installing a tee fitting where the oil pressure sending unit is and then running a line to the turbo. You will also need to drill and tap a oil return line from the turbo to the oilpan.

There are two options for forged pistons and both are expensive.

1) Bore the 200 .050" oversioze if your block can take it, ream the small end of rod and bush it for SB Chevy piston pins and run a Chevy 305 V8 piston. But they arent very cheap either.

2) Go to someone like Ross racing pistons and get and special order forged pistons. Even more expensive (Last quote was about $650 for set)

 

[xctasy]

Although I've not fired my engine up, I can vouch for a good set of forged pistons, especialy the 305 Chev ones. There is a lot of meat in them, the quality is great, and they can be shaved down to 1.45" decks from the stock 1.53 very easily.

Any piston used for a 4-cylinder car will be much stronger than any V8 or six -cylinder stock piston. They have to cope with much more revs, vibration and thermal stress.

However, there are now very good pistons that are not cast which can take the heat, on up to 18 psi of turbo boost in 200 cubic inch engines, up to 475 hp. Best of all, the have shallow deck version too.

Forged pistons rattle when cold, and more damage is done through cold starts than may be saved from detonation at wide open throttle. The shallow deck ones, which allow you to go for stronger, longer rods which can help reduce side thrust, are expensive.

If its just a race engine, go forged. If it is a street'n'strip machine, I'd consider shallow deck ACL pistons, which have ~1.200 decks, and are bullet proof. You could then grab a set of good 5" Pinto 2000 cc con-rods, use the smaller journal size, and bush the huge 0.945" wrist pin for a smaller 0.912" one. The Ford SOHC rods are very, very strong, and the ACL pistons hava a very hard surface and have a great reputation.

It's a Hobson's choice. The good old American forged, or import Aussie ACL's. Could be, once the alterations of rods and pins, that the prices may be similar, but the advantage in using the Aussie ones is the track record of many stout screaming sixes that use them. There are also some ACL ones that are stock Topaz/Tempo 2.3/2.5 size.

 

[Anonymous]

for a forced inducted set up.

the stocko cast pistons would be happy in anything up to 10-12 psi

just get the car properly tuned!!! (ie dyno tuned)

but in my mind you cant go past the acl race series pistons for the 250 x flow. i'd say they could fit ion ur 200 pretty easy. (correct me if i am wrong).

the acl race series pistons are hyperutectic alloy pistons and dont mind boost at all. (PROVIDED YOU HAVE IT TUNED RITE). and the difference between a forgie and a race series pistons is some 1.5 sec of detonation and if you have it tuned rite you will not detonate that long.
other then that just a set of arp style rod bolts and thats all you'll need.

i have a ohc i6 that i have turbo'd with a turbonetics t72 turbo. running 2 bar (32psi). all i have is a stock bottom end with the rods shot-peened and a set of arp rod bolts and a set of acl race series pistons. and my engine develops 740hp.

whats important is good tuning and a very good intercooling set up of some sort- be it water injection or a fmic.

cheers.joe.

 

[addo]

Go Joe! 740 hp is pretty mean. I've tried to explain this before, but quantifying the difference in seconds is a good way to present a case.

I sometimes think that people consider everything Oz after the 2V to be irrelevant, even if it's the best...

Adam.

 

[CobraSix]

How hard are the ACL pistons to find?

I am about mid way done with my information research on adding a Eaton M90 to my upcoming Aussie 250 2v. I plan to convert it to a 4V before the supercharger. The part that was hanging me up was pistons.

I looked at the ACL site, and looked up the race series. Here is my question, They only have them listed for 4.1/250. Can I use those on the 200 since they are the same bore? If so, for a supercharger, I'd want the bigger dish ones right? (to lower compression) or does the dish go the wrong way (up, increasing compression).

I assume yo uAussies may have more experience with the ACL, how are they for quality?

Slade

 

[Anlushac11]

8)

I dont see how you could use them.

The 250 and the 200 have a different compression height, the distance from the centerline of the piston pin to the top of the piston.

 

[rbohm]

8)

I dont see how you could use them.

The 250 and the 200 have a different compression height, the distance from the centerline of the piston pin to the top of the piston.

actually the 200 and 250 used the same piston

200/250 are identical in all dimensions, but have a dish that varied, by year and engine size, to contribute to determining the final compression ratio, i.e. a smaller dish equals a higher compression

that came out of the performance handbook david and dennis wrote. the pistons are the same. and cast pistons can take about 10 psi boost, as long as you keep the rpm's under about 6500. too many rpm's are the real killer of cast piston, along with detonation.

 

[66Sprint6]

ok, heres another, what do yall think would be cheaper, running an M90 or goin with a T3 turbo??? I have dual out headers wo I would have to run a y pipe to the turbo????? I am so serious about this right now, but I want to find what I can do for cheaper (price including everything that must be done), plus be better for the daily drive.
Matt

 

[Anlushac11]

ok, heres another, what do yall think would be cheaper, running an M90 or goin with a T3 turbo??? I have dual out headers wo I would have to run a y pipe to the turbo????? I am so serious about this right now, but I want to find what I can do for cheaper (price including everything that must be done), plus be better for the daily drive.
Matt

If you run the Eaton supercharger then you can run your header. If you want to run a T3 turbo you will need to run a turbo header if you can find one or a J-pipe off of the stock manifold.

 

[xctasy]

Anlushac11:

I dont see how you could use them.

The 250 and the 200 have a different compression height, the distance from the centerline of the piston pin to the top of the piston.

You are right about the Aussie 200 and 250 (3.3 and 4.1) piston being taller than the stock US 200/250 piston (1.60 verses 1.50"). But they are exactly the same compression height as the Topaz/Tempo and 255 V8 pistons, which are used in sixes too, so they can be made to fit easily.

Note that all pre 1970 Aussie engines (188, 200, 221) had US style 1.50" compression heights, and there are still replacements around for these.

Ford USA purposely made the American pistons park 50 to 100 thou below the actual deck of the block, possibly so the production tolerances and compression could be looser. On the Aussie engines, pistons parked more like 20 to 30 thou below the deck at top dead centre, and had pistons with much more dish.

The ACL Race shallow deck pistons are much shorter than this, and can fit up to a range of longer rods. I am certain a rod swap and longer rods whould be cheaper than forged pistons alone.

I'm with gm destroya. I'd spend more money on avoiding the detonation contition by dyno tunning, rather than shovelling more money into forged pistons.

American options:
2.0 Pinto Forged pistons are getting pricey, and it's hard to find +120 thou numbers (3.695") any more. And then, they are taller than most Aussie, Topaz/Tempo/255V8 pistons.

229/305 Chevy forged piston's need a 56 thou overbore to fit, and if you are worried you'll ruin your original block during the boring phase, and theres a small chance it will, then your only other option is Subaru 1.22" forged pistons with the Ford 2.0 Pinto rod.

Then there's Wiesco, Ross, Arias or possibly Jet custom pistons. A set with a real short deck of about 1.1" would allow you to use modified 289/302 Boss con-rods in a 200 I6.

Phew. Things to go with things again.

 

[addo]

In answer to Slade's question re: supply - I can put you in touch (email) with a guy from ACL. He'd be the best bet for how to pick them up in the US.

From memory, I was quoted $450 Oz (local parts store) for the ones with file-fit rings. Not sure if they were race series, though.

Adam.

 

[66Sprint6]

what about these for a Supercharged 200?????
http://cgi.ebay.com/ebaymotors/ws/eBayI ... 2429326590
Matt

 

[xctasy]

Those evil-bay forgeries are 120 thou to big for the block. 3.8" vs 3.68"

Natch!

 

[CobraSix]

Personally, I'm a big fan of turbos versus superchargers on smaller engines. But I would not like to fabricate the necessary piping at stuff to make one work on our engines. Because of that, I'm going Supercharger.

Turbos are generally considered better then Supers. No parasitic drag, very much demand orieted. You can be driving at 70MPH andthe turbo will be making little to no boost. And boost is not RPM dependant. My Turbo Volvo can make full boost at 2000 RPM if the computer would let it. Downside of turbos: Higher under hood heat, more stress on oil trying to cool the turbos, failure of center bearing if not water cooled (many are oil cooled, which isn't as good), and last, but certainly not least...LAG!

Supers have some advantages over turbos. Easier install. Easier to set up to the general style of driving. with Roots or Twin Screw chargers (M90 is a roots), you can adjust the speed of the supercharger to basically make boost at a certain RPM. Just have to remember what RPM your charger starts to really help out and make sure you shift with it.

The other type of supercharger is the centrifugal. Generally more expensive, but from what I've read, a better set up for automobiles.

If you want more information, here are a couple of good sites:

http://www.superchargersonline.com (GREAT reference section)
http://datsun1200.com/modules/nsections ... e&artid=35
http://www.holley.com (look up superchargers).

Slade

 

[Anonymous]

How hard are the ACL pistons to find?

I am about mid way done with my information research on adding a Eaton M90 to my upcoming Aussie 250 2v. I plan to convert it to a 4V before the supercharger. The part that was hanging me up was pistons.

I looked at the ACL site, and looked up the race series. Here is my question, They only have them listed for 4.1/250. Can I use those on the 200 since they are the same bore? If so, for a supercharger, I'd want the bigger dish ones right? (to lower compression) or does the dish go the wrong way (up, increasing compression).

I assume yo uAussies may have more experience with the ACL, how are they for quality?

Slade

well i see your planning a 250 aus motor?? well if you have to import one into the states just have a set of the pistons go with it i'd say. also i have no beefs with the quality of the acl stuff its all good in my books. as for the dish issue..... go for the largest dish to drop compression and the smallest dish to raise. as ur supercharging you'll want a large dish top piston to drop compression.

if you cant get some pistons let me know i am happy to help you out.

cheers.joe.