My CMRE ST2 motor with R heads and 1.7L AR

91supacoop said:
Final numbers were 508 ft. lbs and 502 hp. The power was falling off at 5800 RPM so I'm going to switch to a smaller pulley when I get the motor and rev limit it to 5600.

Seems like kinda low numbers for that much money spent. 500 HP at the flywheel minus 100 (20% drivetrain loss) is 400 HP at the wheels. I would think that for around 10 grand by the time it is installed and ready to drive, you would get a bit more than that.

Hopefully after a good break in time and the smaller SC pulley, you will see some better numbers.

Don't get me wrong... I think those are some pretty nice numbers, but as I said... $$$$ spent -vs- final power doesn't seem like that great of an investment to me.
 
XR7inWI said:
Seems like kinda low numbers for that much money spent. 500 HP at the flywheel minus 100 (20% drivetrain loss) is 400 HP at the wheels. I would think that for around 10 grand by the time it is installed and ready to drive, you would get a bit more than that.

Hopefully after a good break in time and the smaller SC pulley, you will see some better numbers.

Don't get me wrong... I think those are some pretty nice numbers, but as I said... $$$$ spent -vs- final power doesn't seem like that great of an investment to me.
It's not just about the power numbers. For me, I didn't mind spending the extra money I did on my heads just because of the valve train Coy uses.

Another thing to consider (and maybe you are) is that Coy assembled everything, maybe the costs you are figuring are based on self-assembly?

Anyway, I just want to finish by saying "no car is a great investment, especially a SC" :D :D
 
You can have a set of heads ported by an expert and a big valve cut in for alot less than Coy does it and still have the same performance. That's what Sly did and there isn't many people as fast as he is with an M90. Get a good set of Manley valves and some good valve springs and you're set.

You can have a block machined with Wiseco Pistons which are the lightest and strongest piston out there and they aren't expensive. Then you can get some cheapo Eagle rods. They aren't that strong, but good enough for what any of us use.
 
I can't believe people are still complaining about how much going fast costs. I've gone faster than Dan Sly and I've never even had my motor apart. Does that mean I think everyone who put better parts in their motors or spent more money than me got ripped off? Heck no! I paid a whole lot more money for my wheels than just about anyone here on this site. Did I get ripped off? Heck no! In each case money spent is a personal decision and 91supacoop is going to have a very nice motor making top notch power - out of the box! Not after 3 years of jacking around, testing, tuning, trying this, trying that etc.

I am absolutely thrilled with the numbers he has made so far. Before anyone goes off saying that 400rwhp is "in the bag" I'd like to see them do it. So far it's a really short list. Around here it seems that as soon as one person accomplishes a certain level of performance everyone automatically assumes that they and everyone else is going to do the same. Sorry, but there's no pixie dust around here. It takes a lot to get to 400rwhp and if you don't think so just try it. I'll be here to congratulate you when you get there. :)

To me the fact that the motor made more HP than torque tells me that it is under-boosted. It is also quite possible that there are tuning issues above 5500rpm. I know that my motor made huge gains above 5000rpm when I added alcohol injection. I don't know exactly why that was because others did not experience the same gain. I also know that Coy's Stage II R cam was developed for the M90 and IMO it lacks duration to make power above 6000rpm, mainly because the M90 was all done moving air by 6000rpm. Also, in light of recent testing there may also be an issue with the amount of lift some people are running. :cool:

Anyway the numbers are damn impressive and a good 60-70HP more than a typical M90 would make which is consistent with what I've seen elsewhere. Let him take it home, install it, and get it up and running. To me things like this are always the beginning, not the end of the road. :)
 
You haven't taken your shortblock apart, but your top end yeah. Which was what I was talkin about. Or am I missing something?

I wasn't insisting his numbers were bad at all. He'll be making the same power as Dave N. Yeah, put that Alky on, get some more boost then let her rip. Hopefully you find that a different gear setup in a manual tranny is alot better which I have good confidence in.

Dave, can you tune the computer system that Coy uses?
 
CMac89 said:
You can have a set of heads ported by an expert and a big valve cut in for alot less than Coy does it and still have the same performance. That's what Sly did and there isn't many people as fast as he is with an M90. Get a good set of Manley valves and some good valve springs and you're set.

This is true, but I just built a set of heads similar to the CMSII-R heads and I can vouch that there isn't as much margin in them as you might think. By the time you:

Clean, pressure check and bead blast the heads -

Mill the heads for screw-in studs, tap the holes -

Buy the studs and guideplates -

Weld the guideplates (nothing actually fits our motors and remember they're chrome moly) -

Buy a good spring, quality locks, spring cups, titanium retainers - don't forget the cost for cutting in the spring cups -

Install bronze guides, not just K-liners -

Remove all 6 exhaust seats and install larger ones -

Weld up the center intake port and all three exhaust ports -

Spend 12 hrs or so porting -

Buy quality valves -

Then pressure check the entire package again (welding does strange things to aluminum heads...) -

Cut in all the valve angles and then surface the heads -

And then finally add some SS roller rockers (Coy uses Comp Hi Tech rockers) -


After all that I'd like to see how much under Coy's price you could actually come and then I'd like to ask you how much $$ you'd need to make on each set of these cylinder heads in addition to your labor hours in order to meet the overhead on a shop like Coy's for the hours spent going through all those motions and I'll show you a price tag that's not much less than Coy's, if any.

I'm not saying this to give anyone a hard time nor am I suggesting that Coy's money is worth it for everyone. Casey is right that a do-it yourselfer can get excellent results for less money, but when you consider what you get for Coy's money it's not like he's just taking money from babies here. He is earning his money and providing what you pay for. You may not need all that stuff but he's got it if you do.
 
One thing I was kind of wondering. With engine dynos there are alot of factors for HP. You can have inflated or deflated numbers for a couple reasons.

The guy I use for engine dynos has it in a room with closed doors and during the dyno runs my motors start sucking the insulation off of the walls and the barometer falls to 27.xx. It's the first time I've seen oil drip on headers and spontaneously combust.

Then there's what edelbrock and many other companies do for crate motors is run the motor up to 5500 and slap the throttle open and get inflated numbers because the brake hasn't started to embrace.

Then you have corrected altitude factors.
 
CMac89 said:
You haven't taken your shortblock apart, but your top end yeah. Which was what I was talkin about. Or am I missing something?

I wasn't insisting his numbers were bad at all. He'll be making the same power as Dave N. Yeah, put that Alky on, get some more boost then let her rip. Hopefully you find that a different gear setup in a manual tranny is alot better which I have good confidence in.

Dave, can you tune the computer system that Coy uses?

My top end is rather exotic in terms of SC's and I have well over $2000 in the heads & related hardware, however I never ran a camshaft that did it any justice. 210/220 dur .500" lift is just not what the Dr. ordered but I was still making power at 6200 (with the AR) and I was scared to rev it any higher. With a stock S-Port on the car (5% OD) it went 12.50 @ 111mph. IMO this combination was running in top form at the time with pretty close to ideal gearing for the power I was making.

I'm going to change over to screw in studs (more money into the heads) and a better cam when I put it back together this time. I think that someone could run as well as I did just using non-exotic heads. I don't think at the power level I was at that the heads were making the biggest difference. I swapped from some very generic (by comparison) heads to these along with the MP plenum and the 5% OD at the same time and gained about 30rwhp. Considering I paid $1000 for the first heads and cam package and the second package cost $3000 with all the parts I put on, was the 30rwhp worth it? Calculator says no. :/ I might have gotten half of that hp gain with just the $75 pulley. I still like having the $3000 worth of parts on the car and I wouldn't trade back.

I've been working with Mike Tuck a little who has the TEC III also so yes, I can tune it but I don't have a lot of experience yet. As for tuning the top end, I have found that an AFR change of .5 can make the difference between falling off at 5000rpm and making power to 5800rpm. On Jim Oneil's AR it was worth 25rwhp. I dont' have the answer as to what happened on his car but I know that caused it in that case. I have a notion that Coy is probably running the motor very rich to be safe which also suggests why he was running out of injector. I'm guessing he might be a little gunshy at the moment after the whole drama with Ralph.

I also think the AR and associated boost levels make a car a little fickle on the top end. We saw Todd Jelle's car run 12.96 @ 108mph in Denver and then back it up with a 13.20 @ 103mph with no significant changes. We also saw this at the SC Shootout when Michele ran 12.50's all day long and then ripped off a 12.1 in eliminations. I think there is a delicate balance at high boost and high rpm and I'm not sure what is causing it. If I had a car that ran I'd be closer to finding out. :cool:
 
CMac89 said:
One thing I was kind of wondering. With engine dynos there are alot of factors for HP. You can have inflated or deflated numbers for a couple reasons.

The guy I use for engine dynos has it in a room with closed doors and during the dyno runs my motors start sucking the insulation off of the walls and the barometer falls to 27.xx. It's the first time I've seen oil drip on headers and spontaneously combust.

Then there's what edelbrock and many other companies do for crate motors is run the motor up to 5500 and slap the throttle open and get inflated numbers because the brake hasn't started to embrace.

Then you have corrected altitude factors.

I don't know much about engine dyno's but I do know that loading an SC motor is a big part of the #'s you get out of it. How long the motor runs under boost determines how high your intake temps get, for example.

On a dyno jet with an AR intake temps rarely get over 120 deg which puts the motor in the position to make the most HP. On the track those temps will climb to 150 pretty quick and who knows what temps he was getting on the dyno. The TEC 3 also allows you to monitor knock really closely so the HP numbers that Coy gets would be with no knock whatsoever and likely higher air temps than would actually be seen on the track or chassis dyno so it follows that he is probably running the motor at very conservative timing.

I know the V6 Mustang guys tend to run about 13-16deg timing but we all run 24-26 deg at even higher boost levels than they run. I'm not sure what that's all about but I know that this motor is leaving at least 20rwhp on the table going from 14-24 deg timing.
 
This was a good read thats forsure a lot of info to be found at the same time it looks like more people will think that a 400HP SC is easy to do. I will say good luck it's not easy and takes time and money.
 
Jason Wild said:
This was a good read thats forsure a lot of info to be found at the same time it looks like more people will think that a 400HP SC is easy to do. I will say good luck it's not easy and takes time and money.

Truer words have never been spoken. :p
 
Being able to run alot of timing is a lack of efficiency problem. Instead of just saying it's only from low CFM output of a blower we'll just go ahead and say the amount of air being let into the cylinder (compression) from the cylinder head and intake manifold is what determines what amount of timing a motor can use.

The more air let into the cylinder then the less timing is needed, but also the temperature plays a factor too. The lower the IAT's are then the more timing you can run also. For an M90 car the IAT's are a bit higher so that means less timing you can run.

As many know compression turns into heat by itself, meaning, if you have a high CFM output from a blower into a cylinder then the compression stroke alone will create enough heat to reduce the amount of timing needed in a cylinder.
 
CMac89 said:
As many know compression turns into heat by itself, meaning, if you have a high CFM output from a blower into a cylinder then the compression stroke alone will create enough heat to reduce the amount of timing needed in a cylinder.


It all comes down to air density. Alcohol injection increases the "efficiency" of the M90 by creating more dense air. So, we either achieve dense air via compressing more air [CFM] (via a larger blower or a more "efficient" blower) or add water/alcohol to the current M90 mix. Alcohol addresses the IAT factor and not the CFM factor. I'm not trying to school anyone here, just putting it in different words.
 
I was talking about air in just itself. Alcohol injection is just something to help, not at all a solution to the whole problem. All we have are ways to help it, not to get rid of completely.
 
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