New project @ Supertec

[pmax]

Originally Posted by Henry Schmidt

He's pretty convinced his efforts were wasted....He is a true artist with metal so who am I to argue.

I could not agree more. That is why my GT3 has 83,000 miles on it. Remember I walk to work, so none of that is commuting.

My latest 80 something conversion:

Back dated 87 Carrera: 338 hp @ 6500, 301 ft/lbs of torque at 4600 on 91 octane.
3.9, Supertec ITB and Haltec , the "magic" is John Dougherty's 43X, 109 ls cams.
The ITB manifolds were cast in a friend's garage using an MFI throttle body as a pattern and Volvo Mahle pistons for the aluminum. They can work with EFI or MFI.

How about one for your own state ?

CARB compliant EFI EFI EFI.

[Henry Schmidt]

Smog compliance in California is a tough nut to crack. They even have specific catalytic converters that must be employed. For what it's worth, our goal as it pertains to smog compliance is simply to make slight improvements to stock smog engines.
We have a system to eliminate some smog systems on a few specific years but there are limits to what can happen within the laws.

[Henry Schmidt]

Starting with a stock 930 and other parts we have on the shelf.
I believe I'm leaning towards a long stroke 76.4 (993/964) crank with forged rods
97/98mm cylinders, 8.0 compression.
COP, crank fire twin plug
Single K27, small port 36mm heads, Modified CIS, DC15 cams, performance exhaust and a huge inter-cooler.
The goal is massive torque with about 400hp in a street driveable turbo.

[Tonger]

Originally Posted by Henry Schmidt

Starting with a stock 930 and other parts we have on the shelf.
I believe I'm leaning towards a long stroke 76.4 (993/964) crank with forged rods
97/98mm cylinders, 8.0 compression.
COP, crank fire twin plug
Single K27, small port 36mm heads, Modified CIS, DC15 cams, performance exhaust and a huge inter-cooler.
The goal is massive torque with about 400hp in a street driveable turbo.

This sounds like a very interesting project - I'd love to hear your perspective on a couple of related things.

- How does the slightly longer stroke affect boost?

- How much boost do you think you need to run to achieve the performance goals?

- With the struggles of many folks with CIS and 400 hp turbos, I'm interested in following what you do to modify the stock CIS to avoid being overly rich in the midrange while still having enough fuel at redline?

- In terms of exhaust headers, would you favor equal length or shorter unequal length primaries and why?


Thanks for any insight that you can share!

[metalracer]

@Henry Schmidt: is the goal to build a one-off or create a duplicatable product?

Why not offer a baseline of engines with a couple intake and exhaust options? Use the SC/3.2 series for those seeking small displacement, high-revving performance; and the 964/993 series for a work horse 4.0. Give street guys solid and reliable performance without headaches. Make it easy to do the swap and a durable paid shipping crate to return their core to you. Make it easy for folks to get excellent engines PLEASE!

[Henry Schmidt]

Originally Posted by metalracer

@Henry Schmidt: is the goal to build a one-off or create a duplicatable product?

Why not offer a baseline of engines with a couple intake and exhaust options? Use the SC/3.2 series for those seeking small displacement, high-revving performance; and the 964/993 series for a work horse 4.0. Give street guys solid and reliable performance without headaches. Make it easy to do the swap and a durable paid shipping crate to return their core to you. Make it easy for folks to get excellent engines PLEASE!

Thanks for the input. Great ideas for a younger guy. We've tried doing an off the shelf (crate engine) in years passed and inevitably had to break open the engine to do exactly what the customer wanted. The challenge is guessing what the market wants.
As evidenced by this thread, there is no consensus.
The idea of crating an engine is good (that's what we do now) but if the customer has a core, it's best to have that core in advance. That's assumes the core is adequate for the build.
The idea of this thread was not to generate a new revenue stream, We are too busy already. The idea was to get my hands on a personal project mainly to keep my hands busy.

[Henry Schmidt]

Thinking out loud

First step to peanut power....

[PeteKz]

With a flat top piston?

If you build an engine with the peanut chambers and twin plugs, please run the engine on one set of plugs, as well as two, and compare the difference on a dyno. In a tight chamber like that, I would expect the power difference to be significantly less than in the large open chambers with twin plugs.

[Nk993]

Camless using Voice Coil Actuators for opening and closing the valves

[mikedsilva]

Originally Posted by Henry Schmidt

Starting with a stock 930 and other parts we have on the shelf.
I believe I'm leaning towards a long stroke 76.4 (993/964) crank with forged rods
97/98mm cylinders, 8.0 compression.
COP, crank fire twin plug
Single K27, small port 36mm heads, Modified CIS, DC15 cams, performance exhaust and a huge inter-cooler.
The goal is massive torque with about 400hp in a street driveable turbo.

I'm actually slowly gathering parts to build something similar to this for myself.
Except I'm going for 8.5:1 compression... 964 crank, 98mm barrels.

Not totally sure if I will twin plug. With low compression and relatively flattish pistons, is twin plugging still required?

My heads are the large port SC and I am using 3.2 intake manifolds with efi and cop. Cams were just going to be 964 because I have them.

The turbo i have is a Pulsar 3076.. I "think" it will be suitable for around 400hp?

[Henry Schmidt]

Originally Posted by mikedsilva

I'm actually slowly gathering parts to build something similar to this for myself.
Except I'm going for 8.5:1 compression... 964 crank, 98mm barrels.

Not totally sure if I will twin plug. With low compression and relatively flattish pistons, is twin plugging still required?

My heads are the large port SC and I am using 3.2 intake manifolds with efi and cop. Cams were just going to be 964 because I have them.

The turbo i have is a Pulsar 3076.. I "think" it will be suitable for around 400hp?

As we've spoken about so often here, dynamic compression is key to controlling detonation. Turbo charging an engine with 8.5:1 compression and a single plug application will require intricate analysis of cylinder pressures vs. RPM. COP suggests electronic ignition oversight hopefully with knock sensors. I have always found 964 cams to be a little lazy in CIS turbos so I generally opt for SC/Carrera cams. As to EFI tunability, I am woefully ignorant. 400 horse power is a very conservative target. Smart direction for available street gas.

[mikedsilva]

Originally Posted by Henry Schmidt

As we've spoken about so often here, dynamic compression is key to controlling detonation. Turbo charging an engine with 8.5:1 compression and a single plug application will require intricate analysis of cylinder pressures vs. RPM. COP suggests electronic ignition oversight hopefully with knock sensors. I have always found 964 cams to be a little lazy in CIS turbos so I generally opt for SC/Carrera cams. As to EFI tunability, I am woefully ignorant. 400 horse power is a very conservative target. Smart direction for available street gas.

Yes. Full engine management with knock sensor is already fitted. I'm able to dial in ignition and fuel fairly accurately.
I may still opt for twin plugging... I have time.

[Billiam 911 2.8]

After years of canyon and DE driving, my 901/911 5 speed in my 1970 S with 2.8 MFI is showing signs of needing a rebuild. Are there any builders who still make modifications to make these last at high rpm use?
If this forum is strictly for engines, I will post in the 911 technical forum.

Billiam

[Henry Schmidt]

Originally Posted by Billiam 911 2.8

After years of canyon and DE driving, my 901/911 5 speed in my 1970 S with 2.8 MFI is showing signs of needing a rebuild. Are there any builders who still make modifications to make these last at high rpm use?
If this forum is strictly for engines, I will post in the 911 technical forum.

Billiam

Are you looking for advice or someone to build it.
I'm here for either option.

[Billiam 911 2.8]

Thanks Henry.
I am looking for a builder. This is beyond my skill set. What is a good time to call?]

[Henry Schmidt]

3.4 turbo

It looks like we've nailed down the project parameters.
We're going to build a 3.4 liter Turbo.
We're going to use a 74.4 crank with 53mm rod journals. The journal fillets radii were ground oversized to improve torsional rigidity. This will require the use of tapered GT3 rod bearings . That allows us to use PPM GT3 spec rods 130mm. This helps to correct the rod length to stroke ratio reduce piston side loading and increase piston dwell.
Carrera cams set at 1.4-1.7 to advance the cams of better torque at low end.
The custom X brace CP pistons were designed to produce 8.2:1 compression @ .040" deck. Measured compression may change the deck.
Heads are big valve 50/43mm and were ported to 37 x 38.
Fuel head is out to Flowtech to improve fuel volume.
The inter-cooler in a huge aftermarket picnic table.
We'll be using a K27 7200 in conjunction with an 1 5/8" stainless header system.
The ignition will be a single plug 123 with boost retard.
Standard waste gate with a .6-.9 bar spring. Less back pressure should affect how the waste gate responds.
Late 930 transmission is getting shortened to fit early chassis and a KAAZ limited slip is being installed.

The chassis/body is a replica 78/79 factory 935 destined for spirited street use.

[dannobee]

That's awesome Henry!