Best from a 2.0L case

p1967911 · 07-30-2006, 08:34 PM

What is the best build up for a street 2.0L case. High HP, torque, and reliability. Single plug options prefered.

911pcars · 07-31-2006, 01:11 PM

Max. you can go is 2.7 with single plug (RS P/C with 9.5:1 compression) or 2.8 with similar CR. Add S cams or equivalent and late heads. MFI, Webers or EFI. Selective porting.

Details might include ti valve spring retainers, lightweight valves, upgraded head studs, oil pump, blueprinted rebuild specs, balancing, shot peening, electronic ignition and ....... careful assembly with attention to detail. In addition, add chassis dyno time to optimize spark and fuel.

.... or get a 3.6 if you're on a budget. :-)

MHO,
Sherwood

p1967911 · 07-31-2006, 07:21 PM

What kind of numbers can one expect from this?

911pcars · 07-31-2006, 07:44 PM

Quote:

Originally posted by p1967911
What kind of numbers can one expect from this?

For the 2.7/2.8, my rough guess is 200-230 depending on configuration. Others might have other thoughts.

p1967911 · 07-31-2006, 07:55 PM

Anyone?

Cupcar · Cupcar's Garage

In the early 80's I built a 2.7 single plug using an aluminum case and the Euro RS 8.5:1 P/C, 2.2 S heads, S cams and 40 IDA webers with 34 mm venturis and an early S distributor.

The case was modified with squirters for the pistons (theoretically required with the Nikasil cylinders) and the late oil bypass plug for the pressure relief. No boat tail or moon cut on the cylinders.

Engine ran very strong with good throttle response and low end was OK in my 2050 pound 914/6.

I think it was Lou Malone at AJ Racing who gave me a dyno sheet of an engine he built that was similar; the dyno run showed 220 HP- more than a mechanically injected 2.7 RS but his was with open exhaust presumably.

kenikh · 08-02-2006, 03:47 PM

BACK UP.

Is this 2 liter case aluminum or magnesium? This is the biggest factor in getting relaible HP from a 2 liter case. If this is a mag case, you would be doing your wallet a disservice by boring the spigots. You'd be lucky to get 50K miles out of a 2 liter mag case that was bored for 90mm pistons. Additionally, you typically don't want to go over ~200 HP on a street driven 2 liter mag case without MEGABUCK machine work. That said, using Nikasil barrels and 86mm JE pistons (these fit stock spigots) at 9.8:1 CR, 70.4mm crank (2.5L) and the right cams, you could make 230+ HP.

If it is aluminum, you can reliably build a 2.8 screamer that puts out 100HP/liter.

kenikh · 08-02-2006, 03:51 PM

BTW, I assume it is aluminum since your name references a '67 911.

911pcars · 08-02-2006, 10:35 PM

230+ HP out of 2.5 liters depends on the "right" cams. However, the cams necessary for this amount of power might take this out of the realm of a streetable engine.

Weren't RS engines built around the mag case?

Sherwood

304065 · 08-03-2006, 03:12 AM

Seriously, with the value of SWB stuff escalating, don't cut the case for a street car. Get yourself the parts from a 2,4 and have the case modified for better oil pump, squirters, oil bypass mod.

A 2,4 on that case will be virtually indistinguishable from original and can be put back later. You will also need the heads from the later application.

Why not just rebuild the 2,0? People who buy '67 911's dont do it for the wide tires and huge horsepower, they do it because the car is a time warp machine, back to the days of 165 skinny tires, green gauges with chrome ring, and the flexibility of the early engine. If you want to go fast in a straight line, consider a 930. If you want to go fast around corners, put the $$$ into the suspension and keep it flat longer

kenikh · 05:58 AM

Quote:

Originally posted by 911pcars
230+ HP out of 2.5 liters depends on the "right" cams. However, the cams necessary for this amount of power might take this out of the realm of a streetable engine.

Weren't RS engines built around the mag case?

Sherwood

Yes, the RS car cases were magnesium; a 7R mag case, though. A 2 liter mage case means that the case is a 1R case, which had none of the rigidity improvements of the later 7R. They just can't be stressed like a 7R (which also has a larger spigot bore, other than the 73.5 CIS 2.4 case).

As far as getting streetable cams that make that kind of power, trust me, it can be done. John Dougherty (camgrinder) has some wicked profiles that will allow 90HP/L if you are willing to get a little bit exotic with your valve train. The cams I bought from him are expected to make 190 HP on my 2 liter car; oh yeah, the torque curve is significantly fatter than a stock 'S' cam, too! They should be going in sometime in the next month or two.

On another note, I also feel that cutting an early aluminum case is a tragedy.

Hope this clears some things up.

Cupcar · Cupcar's Garage

I think if you really want bang for the buck in the power department and reliability and are going to change the case anyway, go for an aluminum 3 liter case and build something bigger than 3 liters.

No substitute for displacement and it is a waste of time to mess with a mag case unless you already have one, and then the 7R is the only one worth hot rodding IMHO.

kenikh · 08-03-2006, 07:35 AM

I agree with cupcar: unless you have some demented interest in hot rodding an early mag case (like I do), the best way to go is to use an SC engine as the basis for your project. Best bang for the buck, by far.

shbop · 08-03-2006, 08:06 AM

Kenik, OK, I'm very curious. Would you mind sharing the info on this latest project? Sorry, don't mean to hijack the thread, but the bait was too irresistable. Thanks!

kenikh · 08-03-2006, 08:42 AM

Quote:

Originally posted by shbop
Kenik, OK, I'm very curious. Would you mind sharing the info on this latest project? Sorry, don't mean to hijack the thread, but the bait was too irresistable. Thanks!

Here's what I have to say; if you have any more questons, please PM me:

Here was the intial plan: it was going to be run 81mm Cosworth ultra-lightweight pistons in 81mm Nikasil bores, 10.5:1 CR w/ twin plugs. Unfortunately the pistons I was going to buy were out of spec, so I am going to stick with my stock 2 liter 'S' pistons for now.

I have already ordered the cams and had them delivered to Henry: They are a custom flavor of John Dougherty’s DC44, running on 102 lobe centers. They lift .490 at both valves. They have very fast ramps, so overlap isn’t an issue at low revs. It will need a top notch valve train, but that is in the cards, too. It will eventually run special headers designed by Steve Weiner and built by Headers by George.

Speaking of the crank, I was planning to run Pauter rods and have the crank fully gone through and zero balanced by Ollie’s, but have decided to hold off on the complete rebuild; my bottom end is dry and relatively fresh. As a result, I may actually back the cam timing off by a degree or so (for now), so I can take advantage of the extra overlap. Since I am not doing the balancing work now, I woouldn't be comfortable revving the motor to the moon until I have the lighter rods and crank work done.

It will be topped off by the 2.0S MFI system I have sitting in a box in my garage. In the intial configuration (10.5:1, high revs), I expected it to make somewhere between 90 and 100HP/L at the crank; which both camgrinder and Steve Weiner verified as reasonable expectations. In the intial config, the motor was expected to make rising power to 7800 RPM, then fall off ~5HP by 8000 RPM, meaning 190 - 200 HP. In the slightly detuned trim, I expect between +/- 180 HP with a significantly more robust torque curve than 'S' cams in both configs.

Sound like fun?

shbop · 08-03-2006, 09:13 AM

Absolutely!

Cupcar · Cupcar's Garage

Talk about dementia. Here's a weird one my friend and I built.

Used NOS Mahle 2.5 racing pistons from the 70's in 86.7 mm bore. They had a wierd barrel spigot size of around 94 mm or so but there was plenty of meat on the barrels to cut them to the 2 liter case size.

Used them with bone stock 2.2 S heads, Garretson GE 80 cams, 40 IDA's with 36 mm venturis, Aasco valve springs, Ti retainers, usual windage mods to the case and squirters. Carillo rods.

The compression came out at 9.76:1 after doing a very careful cut around the perimeter of the head for clearance to 0.038" so as not to lose too much volume. Displacement came out at 2337 cc with a 66 mm crank (would be 2494 with 70.4 crank they were designed for)

1.5" headers merging to Burns collectors with around a 28" primary leading to a 24" megaphone if I remember correctly.

Anyway made 101 HP/liter on the dyno- used 35 deg advance!!

p1967911 · 08-07-2006, 04:02 PM

So here is the delemia, the car is a '67 the motor a '65. I know squat about porsche, only ridden in one once. I want to keep the car looking stock so a 3.xL transplant is out. So lets say we don't cut the case but make other mods (heads whatnot) what to do? and what kind of numbers will it produce?

Brant · 08-07-2006, 05:52 PM

a 3.0 can look pretty stock to the untrained eye.
your going to have to spend a pretty good bit of money to surpass factory numbers for the S using a 2.0 block. so your going to end up with more money into this for less HP than a 3.0

you can take easy to come by 3.0 and do a few minor things to it and install carbs for less than your talking about spending in order to get 150hp on that 2.0 case.

nearly anything is possible.
you can get 200 or 230hp on that case of yours... but it could be a motor that is measured in hours instead of years, and could end up costing anywhere from 10 to 20K

I have a 2.0
I love it.
but I don't want 300hp out of it, and know that if I did I would need to change motors.

so if you don't want to spend an arm and leg then shoot for 150hp.
brant

p1967911 · 08-09-2006, 06:21 AM

Bump