3.0 SC HP Expectation - post modification

[D911SC]

I don't trust myself without a rev limiter! You are a better driver than me Tom. It's good to know that some guys are running 7500 on stock rods. I'd probably still err on the side of caution but something like 7300 seems safe enough but still giving me a long enough in the 'power zone'. There might be more HP with better rods but I have to limit the $$ somewhere. This engine is already looking like costing more than my wedding, but don't tell my wife.

There's definitely mixed reactions about this DC60's. Aaron - when I'm getting closer to the build I'll have to get in touch re a suitable distributor.

Anyone got any videos of a car running with this kind of setup? It would be interesting to see how it idles and drives.

[tom1394racing]

Originally Posted by D911SC

. This engine is already looking like costing more than my wedding, but don't tell my wife.

Yeah....Mine cost as much as my daughter's wedding :-)

[lindy 911]

Your combination with GE 60 cams is as street-able as it gets for a hot-rod. It is very easy to drive and acts very stock under 3,000 rpm; it's hard to tell it's a hot rod. Anyone who tells you that these cams aren't street friendly hasn't driven this combination. As I have said many times before, it's what makes you happy and if you already have the cams purchased use them. Any change in cam at this point IMO is throwing money out the window.

I'm not trying to make any personal attacks on anyone's opinion here just trying to share with you that the cams you already have are a great choice. Perfect? Maybe not but neither is anything else. All cams are a compromise.

Lindy

[MrPerkles]

My c3 rebuild just made 270 @ 6000 revs with dc62s its perfectly streetable and pulls clean in any gear low down
A lower rocker oil leak stopped play before any ignition tuning etc.Its back on the dyno Friday for a map at full revs,will post charts later

[D911SC]

Originally Posted by lindy 911

Your combination with GE 60 cams is as street-able as it gets for a hot-rod. It is very easy to drive and acts very stock under 3,000 rpm; it's hard to tell it's a hot rod. Anyone who tells you that these cams aren't street friendly hasn't driven this combination. As I have said many times before, it's what makes you happy and if you already have the cams purchased use them. Any change in cam at this point IMO is throwing money out the window.

Lindy

Thanks again Lindy. As I mentioned in an earlier post I have been watching your build with keen interest.

As you say I have already bought the DC60's and the most recent comments from yourself and others about these cams has me very keen to use them.

Driving like a stock car under 3000 and then feeling like a hot rod after that is the kind of engine I'd like to own!

When I do the build I will get another thread going.

Thanks for all the comments.

[kenikh]

FWIW, it would be fun to try them. No harm, no foul right? Since you already have them, the worst that might happen is that you might decide that some port work is in your future one day. The net-net is that is sounds like the motor would be fun, so I'd say go for it.

[D911SC]

Thank kenikh - I have already planned some porting. Seems like it is a 'must do' with this mod.

[kenikh]

Originally Posted by D911SC

Thank kenikh - I have already planned some porting. Seems like it is a 'must do' with this mod.

Then I would be remiss in not recommending Steve Weiner's magic ports. MAGIC.

[PFM]

kenikh,

The ports look good from Steve. What is the valve size and what are the flow numbers? The real numbers I would like to see are the port velocity numbers mapped across the ports, in and out. And what size motor are they designed for?

Regards,

PFM

[kenikh]

Originally Posted by PFM

kenikh,

The ports look good from Steve. What is the valve size and what are the flow numbers? The real numbers I would like to see are the port velocity numbers mapped across the ports, in and out. And what size motor are they designed for?

Regards,

PFM

Heh heh. You are right to be skeptical, as I have seen some BAD port jobs that looked good. I think those aftermarket billet heads are some of the worst POS CNC hunks ever, but they aren't priced that way.

But the fact that the name Steve Weiner doesn't immediately elicit blanket respect belies a little noob. We were all there, but Steve is one of the good guys and by sticking around a while, you'll certainly absorb more than a fair share of useful nuggets from him.

Let's put it another way: these heads on Cam Arnott's 2.25L motor dynoed 225HP at 7500RPM (HP peak is actually 7800, but he cut the dyno short). The torque curve looked like a twin to 2.2E until 4000 RPM, after which it went straigh up like a rocket and looked like a 906. Yup, cake and you get to eat it. Amazing.

These heads are the real deal.

Woops forgot to add a link to answer your other questions:

http://www.early911sregistry.org/forum/showthread.php?t=22220

Forget the port specs, as the heads are cut 3-dimensionally as a tapered venturi from port to valve. If you measured them, they'd be 39mm-41mm depending on where you measure them. They are VERY special indeed.

[MrPerkles]

DC62 idle like a pussy cat
DC62 up to 6000 revs

[lindy 911]

Do you have the results of the dyno pull and would you please post them?

Lindy

[MrPerkles]

Originally Posted by lindy 911

Do you have the results of the dyno pull and would you please post them?

Lindy

270 on that run an oil leak stopped play before any real tuning so going back Friday

[lindy 911]

270 Hp at the rear wheels with GE60 cams at 6,000 rpm; Wow! That kind of debunks the notion that these cams require high revs to make power. Can you share the torque numbers?

Thanks!

Lindy

[MrPerkles]

Originally Posted by lindy 911

270 Hp at the rear wheels with GE60 cams at 6,000 rpm; Wow! That kind of debunks the notion that these cams require high revs to make power. Can you share the torque numbers?

Thanks!

Lindy

fwhp

[kenikh]

Here's a table of the varying overlaps of these cams. Lower overlap typically means more low end grunt and lower peak HP RPM.

[kenikh]

Originally Posted by PFM

kenikh,

The ports look good from Steve. What is the valve size and what are the flow numbers? The real numbers I would like to see are the port velocity numbers mapped across the ports, in and out. And what size motor are they designed for?

Regards,

PFM

Found the dyno sheet:



Cam being an Aussie, it is in kw not HP. His caveat is that the carbs were not well tuned for this pull, so it looks looks like 182 RWHP for a corrected 210 DIN HP...RS territory. So the 100 HP/L number he initially thoughts was a little high, but not too far off. What is amazing is how they keep making power over 8K, given the torque curve! Other than the little blip that is likely due to the carbs, that curve is FLAT.

I actually designed the motor and was going to build it, then decided I wanted more displacement. They heads are '69S, w/ '69S valves and the motor is 2.25L (85x66). Let's just say that the amount of time I spent in design left no stone unturned in pursuit of power extraction.

The only difference between the motor cam built is that mine would have used my taper bored MFI stacks and custom blends TBs and purpose designed headers, also from Steve Weiner. My guess is that trimmed to my spec, peak HP would have been up another 10HP and torque would have been even fatter down low due to improved scavenging. Cameron ended up using PMO carbs and SSIs.

Damned impressive for carbs and a restrictive exhaust!

As far as the heads go, the ports are custom scaled to fit your motor spec, so if you wanted these on a 3 liter, they'd be scaled to suit in the computer model then cut.

[D911SC]

Don't want to milk this thread too much but I couldn't resist posting these pics of what arrived in the mail today!

There is no turning back now

Thanks to JD of Dougherty Racing Camshafts for answering a couple of questions I had about these.

Also thanks to Lindy911 for prompting me to look at these. Looks like we may be building a very similar motor.

[lindy 911]

I know this will probably start a new debate over usefulness but here goes anyway; I had my piston tops coated with a thermal barrier polymer from Poly-dyne in Houston. I also had the sides of the piston coated with an anti-scuffing coating from the same people. To date, I don't have an auxiliary oil cooler mounted, just the engine cooler. My motor has not been more than 2/3 up the temp gauge! Now I haven't run it that hard yet but I'm convinced this is a good thing to consider.

It cost about $200 to get the pistons done and another $100 to do the rod and main bearings with the same stuff as the piston skirts. The piston thermal barrier effectively keeps the combustion heat from soaking through the piston crown, therefore reducing the heat transferred into the oil via the squirters. This is a good thing considering these motors are know for running hot.

More food for thought.

Lindy

[jpnovak]

Coatings are good! I coated every moving part in the top end of my motor as well.

My motor runs very cool and very efficient. I definitely think it is worth it.