Turbo 250?

[Anonymous]

Sorry if this has been brought up before, I tried searching by found no results.

I decided rather than swap in a 302 into my '66 Mustang ( *yawn* been done by everyone) a turbo 250 could make just as much streetable power and be alot more interesting.

I've seen lots of discussion about turbo 200 builds and found plenty of information on rod/piston selection ect... but nothing for the 250.

I know the deck height of the 250 leaves alot to be desired, thus the desire for 255 pistons. But what about rods? Has anyone found a nice rod/piston combo for the 250... or is it just stock rods and try to find forged 255 pistons?

My goal is going to be 300hp/300ft-lbs so I'll have to be running a deceint amount of boost. Also looking at the Al Aussie head and EFI.

Any input is appreciated

 

[CoupeBoy]

I think you need to look up some posts by Wil (Does10s). He has a turbo 250 in his '63 falcon putting out numbers similar to what you are looking for. He also has this site
http://www.cardomain.com/ride/686815

I think he is still running a stock motor with around 10-12lbs of boost.
-ron

 

[Anonymous]

there are two theories floating around that will remedy the 250s short rods

1. Theoretically you can use the standard height pistons
and use the 6.0" 2.3L HSC rods.
2. use the ford 300 6.21" rods with the Iapel 1.24" forged flat top
pistons. You should first figure out what your static compression will
before choosing to go this route. The Iapel pistons can be found
here.

 

[addo]

Another option is to use Australian long 200 rods (6.27"), with hypereutectic pistons readily available to suit. Note that the present Falcon Turbo and variants run hypereutectic pistons, not forged - but still makes excellent grunt. The latter will offer more durability under extreme conditions.

You could also join fullboost.com and browse around.

Regards, Adam.

 

[XFlow_Fairlane]

if money is no option to a certain point I would say AL SP head and some stand alone EFI with a header like wills. should EASILY put you into the 300/300 range (prob more like 300/400 though)

 

[Anonymous]

I had seen Does10's posts before, but I thought he was running a turbo 200!

I know that factory compression is pretty low, which is nice for boosted apps but how much does the lack of quelch area hurt things? I'm not used to turbo gasser motors so I'm still reading up and learning before I start buying up parts.

Addo: I'm guessing you mean fullboost.com.au? fullboost.com doesn't bring up anything for me. I'm checking out the site now though.

 

[addo]

That's the one!

 

[Anonymous]

In Oz the 250 is the more commonly used engine for turbo applications but it is much more difficult to get the compression down than the 200 engine.

ACL in australia make a hyperutectic pistons with a 27.9 cc dish which also runs about 1.5mm down from the deck (as all standard pistons do). Combine that with a bit of chamber work and you can get down around 7.8 or 8:1 compression ratio which is acceptable for turbo application. Some guys run as high as 8.5:1.

I use the standard 5.87" rods which are just linished and shot peened. If you want to go the long 6.27" rods then the aussie 200 rods are no good as they are very weak. The 300I6 F100 rods are a better choice but you will need a very shallow dished piston which will need to be custom made to order.

Using the aussie alloy crossflw head is definately the way to go as there is a huge amount of heat to contend with on the exhaust side so you don't want that anywhere near your inlet manifold.

 

[Anonymous]

I should have been more specific with my power desires. 300/300 at the wheels, so it's a fairly stout goal. I could do it N/A, but that would sacrifice alot of streetability.

So what I'm getting from you guys is probably needing custom pistons unless I can find some 2.3 HSC rods? But how strong are the 2.3L rods?

The way I see it the SP is the only way to go and really the price isn't bad at all considering what you get and what a comparable V8 setup would run. Mark, you mentioned heat conisderations.... convection between the header and intake manifold is easy enough to control, are you talking about conduction between ports in the head itself?

I don't mind spending a little extra money to do it right, it's a long term project but I save money by doing most everything myself. I mean, I've been working on the car for nearly 10yrs now. Runs great, handles great... but there will ALWAYS be something more I can do or some new idea I come up with. ( You should see my suspension plans!)

 

[Anonymous]

The heat I am talking about is radiation mostly. The type of radiation where i managed to burn my arm removing a spark plug lead even though my arm was still 6 inches away from the turbo!

I also have 2 pac paint which has blistered off my inner guards which are about 4 inches away from the echaust manifold. Boiled the brake fluid in my master cylinder once before I made a heat shield for it. Things like that!

300hp is a very modest goal. One thing I found when I initially had modest goals was that I used a smallish turbo and I had my 300 hp by 3300 rpm then the turbo choked the exhaust flow and power would start to drop after that.

It is 480 ft lb of torque at 3300 rpm! It was terrible to drive. Basically light the tyres up at 2000 rpm then fall on its ear as soon as it got going. Always go huge on the turbine housing and wheel compared to what someone else has on their supra or skyline because the low revving big stroke big cube 250 engine chokes up on exhaust flow a lot easier than those import engines

The thing is that the size turbo required for a nice 300 hp engine which doesn't peak at 3000rpm is actually a fair size turbo. A good streetable combo is a T04E 1.0A/R turbine housing, P-trim turbine wheel, V2 compressor wheel and 0.6 or 0.7 A/R T04E compresser housing. With a good cam a bit of head work and boost around 6-10 psi you will have your 300hp with boost before 2000 rpm and a good progressive boost onset and good throttle control of the boost. The thing is that turbo will be good for 450hp easily if you screw the boost up to around 15 psi. The temptation is always there ;-)

 

[Does10s]

Dieseler,
The 250 in my wife's '63 Falcon is totally stock other than the FSPP cam and ARP bolts/studs. Cast pistons and all! We've run up to 18lbs. of boost without any problems. We just recently popped a head gasket when I bumped the timing up a few degrees.
Our setup is very simple. We selected the 250 over the 200 because of one reason.....50 cubic inches! I knew we weren't going to spin this motor to the moon to make it go fast. We were just going to spin the turbo hard at lower RPMs and let it make boatloads of torque!

Later,
Will

 

[Anonymous]

Mark: Sounds like you need to get that turbine housing thermal coated!!!
I had been thinking a T04 might work well, thanks for confirming that and the detailed specs!

Does10's: So no problems related to the low deckheight so far, seems far from the ideal setup... but looking at your numbers it seems to work well!

Am I missing a techsection on fullboost somewhere? I think i've been through pretty much the whole site and not found much information.

 

[addo]

You probably haver seen it all. Like most similar sites, there's a lot of flash and a lot of "hot air" but there are some well-built six cylinder cars running good times. Once identified, you can always hunt them down via another forum or emails.

The sixes here are predominantly crossflow; it's common and a good power base.