Your opinon welcomed.

[rbeeson]

I have just about got everything together for a 2276cc motor (Going in my rail buggy). Here is my plan.
 
Mahle 94mm (w/thermal barrier coating)
Empi 82mm crank
CB Performance "Bigfoot" 2212 cam:    294 adv. dur.
                                                                .601 lift (w/1.4 forged rockers)
Already had the cam on the shelf and thought I would save a C note. 
 
CB Performance Wedgeport (44 x 37.5) CNC ported. Flows 201 cfm @ .600 lift. Combustion chambers, valve ends, and exhaust ports coated with thermal barrier coating. CB Performance Big Beef IDA manifolds cnc matched to heads. 0.060 copper head gaskets.
Chromoly push rods
5.39 connecting rods (Balanced both ends and total)
Weber 48 IDAs that I have cleaned up and streamlined for better flow.
 
I used the kb-silvolite CR calculator to figure the Dynamic CR and know what I needed the heads flycut.
We have 93 octane gas hear locally and I think I might mix in some 100 octane aviation fuel to help.
With the intake valve closing @ 62 degrees and a 46cc chamber (0.060 copper gasket) that puts my SCR right @ 11.0 to 1 and DCR right @ 9.0 to 1. The gentleman @ a nearby VW Speed Shop said that 93 octane would support this CR and Pat Downs (CB Performance) ran an 11.0 to 1 CR probably a little over 8.5 DCR with an FK-89 in the 2006 CHICO Engine Builder Show Down on pump gas. The thermal coating also helps against detention plus it will help keep the heat in the chamber and cooler heads.
 
Thoughts on power range?
Thoughts on any of it?
Thanks
Reese

[eduardocastrejon]

4 months ago, I bought cb wedgeports,
cb have machine shop service
http://www.cbperformance.com/services.asp
50 usd to flycut the heads,

then you can ask the heads with the desire cc in combustion chamber

also consider the springs upgrade, I dont have the issue yet but many users says that the valves float

question.

the heads came with 67 cc ,
why do you want to flycutt the heads and later use the 60 copper heads gaskets ?

dont forget to add your desired deck height to the calculator

what is your deck height ?

[fiatdude]

Pretty short rods for any kind of RPM

[rbeeson]

Pretty short rods for any kind of RPM

I'm gaining knowledge. Could you explain the rod ratio theory?

[madoski]

With all that you're putting into this, why go with an Empi crank?  I'd go with a good quality Scat, CB, or DPR.

[Aussie Rob]

x2 on longer rods. For the street in a low rpm 2276 that length of rod would work fine but i figure your revs in a sand rail will be up in the rpm range.
So many inexpensive I beam rods with arp bolts at 5.5" length would work well.
I guess your aiming for a zero deck hence the 60thou copper gasket.
Sounds like a workable combo.....have fun!

[so67vw]

I actually like the shorter rod myself... I went from 5.6" to 5.4 rods about 7 years ago an never looked back... The motor is snappier and narrower... That is a serious cam though... Though it was on the shelf, cams are cheap... I'd personally figure out all of the other parts in the combo and choose the cam afterward (or have one made for your combo)...

[VdanielW]

Was just running the #'s on the kb-silvolite site and was wondering if you added the 15 deg's to the cam like the calculator states.  If you didn't you should have put in 77.  This will give you a dynamic compression ratio of 7.9:1 rather than the 9.0:1 that you got.

[mmccarthy]

We have 93 octane gas hear locally and I think I might mix in some 100 octane aviation fuel to help

av gas is rated differantly than regular gas( lower octane)  , if you are going to drive it on the street I would just set your compression ratio up for the 93 octane fuel .

[rbeeson]

Was just running the #'s on the kb-silvolite site and was wondering if you added the 15 deg's to the cam like the calculator states.  If you didn't you should have put in 77.  This will give you a dynamic compression ratio of 7.9:1 rather than the 9.0:1 that you got.

No I didn't add the 15. I have visions of grandeur and am learning to turn it down. I have access to a set of 1:25 rockers which would bring it down to .537 with that cam. Thank you VdanielW.

[rbeeson]

We have 93 octane gas hear locally and I think I might mix in some 100 octane aviation fuel to help

av gas is rated differantly than regular gas( lower octane)  , if you are going to drive it on the street I would just set your compression ratio up for the 93 octane fuel .

Now that I've learnt that my DCR will be close to 8 I will be in better shape for 93 octane.
I appreciate the input guys.

[rbeeson]

I actually like the shorter rod myself... I went from 5.6" to 5.4 rods about 7 years ago an never looked back... The motor is snappier and narrower... That is a serious cam though... Though it was on the shelf, cams are cheap... I'd personally figure out all of the other parts in the combo and choose the cam afterward (or have one made for your combo)...

This was exactly my thoughts on the rod ratio. My buggy is street legal but it will not be a daily driver so I thought I'd go a little more "saucy" than an everyday driver.

[rbeeson]

With all that you're putting into this, why go with an Empi crank?  I'd go with a good quality Scat, CB, or DPR.

Empi would not be first choice but I had it from a purchase of parts with a block that was already prepped for 2276. I also recieved in the purchase a DPR crank that they said was no good but I was going to get around to a second opinion. My Dad had some of the combo (heads and carbs) that had been setting around for a few years. I have sort of stumbled into the parts that I have (no I didn't steal them) and just trying to do the best I can with what I have available while trying to keep the cost down.

[rbeeson]

Pretty short rods for any kind of RPM

I was hoping to make my power lower down the RPM range. I'm still learning. It seems to me picking your setup is all about compromise. Wouldn't be nice to get 200hp and 40mpg out of these little engines?

[so67vw]

There is a lot to learn.... My best advise is be careful about who you listen to... There is a lot of theory and Voodoo out there that comes from guys who have never actualy built a motor... In fact most of the garbage I hear comes from guys who barely know how to gap a spark plug (if that).... I take advise myself from guys that I absolutely know I can trust and even then I question it before I act.... Everything else is just mumbo jumbo or unbackable opinion......

[rbeeson]

There is a lot to learn.... My best advise is be careful about who you listen to... There is a lot of theory and Voodoo out there that comes from guys who have never actualy built a motor... In fact most of the garbage I hear comes from guys who barely know how to gap a spark plug (if that).... I take advise myself from guys that I absolutely know I can trust and even then I question it before I act.... Everything else is just mumbo jumbo or unbackable opinion......

Very good point! Thank you.

[JVance]

Everything else is just mumbo jumbo or unbackable opinion......

...or dogma.

[mmccarthy]

 From past experiance I would have the crank wedgemated, my first long stroke engine destroyed the flywheel dowel pins when I launched it. Since then I have had every race crank bigger than 78 stroke wedgemated.  If you don't plan to do any holeshots it wouldn't be needed.  I also used 5.5 rods in my 2275, had no interferance problems between the wrist pin bosses and the crank counterweight with them. If this is your first build I would find a machine shop locally to have your bearing clearance checked. Take your bearings and install them into your case, torque it to specs then have the machine shop run a bore guage inside the crank bore and measure each journal. write the numbers down and then have them mic the crank, subtract the crank number from the bearing number and you have your bearing clearance. Because you have a new crank, bearings, and case does not mean your clearance is correct, hope you do not have any suprises.   Mike McCarthy

[Mike Lawless]

Here's some good info. A little dated but still solid. Mark Herbert knew a thing or two about fast street motors.

http://www.cal-look.com/building-a-fast-and-reliable-engine/

[rbeeson]

From past experiance I would have the crank wedgemated, my first long stroke engine destroyed the flywheel dowel pins when I launched it. Since then I have had every race crank bigger than 78 stroke wedgemated.  If you don't plan to do any holeshots it wouldn't be needed.  I also used 5.5 rods in my 2275, had no interferance problems between the wrist pin bosses and the crank counterweight with them. If this is your first build I would find a machine shop locally to have your bearing clearance checked. Take your bearings and install them into your case, torque it to specs then have the machine shop run a bore guage inside the crank bore and measure each journal. write the numbers down and then have them mic the crank, subtract the crank number from the bearing number and you have your bearing clearance. Because you have a new crank, bearings, and case does not mean your clearance is correct, hope you do not have any suprises.   Mike McCarthy

Good to know. Thank you.

[madoski]

Now that I've learnt that my DCR will be close to 8 I will be in better shape for 93 octane.
I appreciate the input guys.

Remember that the EPA is trying to up the ethanol content in pump gas to 15% (it's already 10% at a lot of places).  I don't know if that would be enough to let you raise your CR a bit...I'm not an engine guru like some of the guys advising you here, but I know that theoretically, the more E, the higher compression you can get away with.  Maybe all it would affect is your jetting.

[so67vw]

Here's some good info. A little dated but still solid. Mark Herbert knew a thing or two about fast street motors.

http://www.cal-look.com/building-a-fast-and-reliable-engine/

No smoke and mirrors there.... Mark was always straight up when he gave advise, and very kind about it....

[Ohio Tom (DdK)]

The difference between a stock length rod and a 5.5" rod on a 82 stroke crank has little affect on rod ratio. The difference between them is very small.
I choose the 5.5" rod for piston skirt clearance. and it keeps the piston .100" farther "in the hole" of the cyl thus reducing the amount of scuffing on the piston skirts.
Short rod motor that are revved high will scuff the crap out of the piston skirts, then take out the rings too.
Keep those things in mind when choosing a rod length.
 

[rbeeson]

Was just running the #'s on the kb-silvolite site and was wondering if you added the 15 deg's to the cam like the calculator states.  If you didn't you should have put in 77.  This will give you a dynamic compression ratio of 7.9:1 rather than the 9.0:1 that you got.

What is the reason for adding 15 deg's?
The Pat Kelley program and few others I've found don't say anything about the 15 deg's. Am I missing something?

[so67vw]

I choose the 5.5" rod for piston skirt clearance. and it keeps the piston .100" farther "in the hole" of the cyl thus reducing the amount of scuffing on the piston skirts.
Short rod motor that are revved high will scuff the crap out of the piston skirts, then take out the rings 
 

Ok so I have pulled out three sets of old 94s that I have (two pulled from valve seat dings/old Dee S/E heads and one that I pulled to replace with something better).... None of them are scuffed up.... As I see it, unless you are running longer barrels the 5.4 is gonna get you the same surface area on the barrel... My reasoning is because it seems every time I do it I only have a .010 barrel shim to get me zero deck.... I have never has skirt clearance issues...

[DonPauter]

I choose the 5.5" rod for piston skirt clearance. and it keeps the piston .100" farther "in the hole" of the cyl thus reducing the amount of scuffing on the piston skirts.

Tom, I need a little help with this one, not sure what you mean.

[Ohio Tom (DdK)]

Sorry, somtimes I can be too genral in my statements.

To clarify: With a stock length rod and 82 stroke crank, I have run into issues on a few builds where the either the piston skirts will hit the crank counterweights, or the piston skirts will hit the case reqiuring extra clearanceing of the case. No big deal, just extra labor.
Also, the shorter rod will pull the piston farther out of the cylinder at BDC (all else being equal).
It's amazing how far the piston comes out at BDC anyways.
The way I see it, If I can build a motor that keeps the piston .100" farther in the cyl at BDC, it "should" help with problems of scuffing piston skirts??
I have no imperical data to support that claim.

My thoughts are this: If I can just use a 5.5 rod (over a 5.4" rod), the rod ratio doesnt change much at all, and I can build the motor with fewer clearincing issues, and "maybe" be helping in some small way to help with suffing, then these all seem like steps in the right direction.

[rbeeson]

Sorry, somtimes I can be too genral in my statements.

To clarify: With a stock length rod and 82 stroke crank, I have run into issues on a few builds where the either the piston skirts will hit the crank counterweights, or the piston skirts will hit the case reqiuring extra clearanceing of the case. No big deal, just extra labor.
Also, the shorter rod will pull the piston farther out of the cylinder at BDC (all else being equal).
It's amazing how far the piston comes out at BDC anyways.
The way I see it, If I can build a motor that keeps the piston .100" farther in the cyl at BDC, it "should" help with problems of scuffing piston skirts??
I have no imperical data to support that claim.

My thoughts are this: If I can just use a 5.5 rod (over a 5.4" rod), the rod ratio doesnt change much at all, and I can build the motor with fewer clearincing issues, and "maybe" be helping in some small way to help with suffing, then these all seem like steps in the right direction.

Well said Tom.

[so67vw]

Let me be more clear about this then... There is nothing wrong with play'n it safe or doing what you feel comphy with... Every engine builder has his preference... I just hate to see people get told that they are gonna gave problems when I know better.... If you wanna use a 5.5 rid then that is cool... There is nothing wrong with that at all... You will though, have a .100" (or so) spacer behind the barrel... This will obviously make the motor wider... In some (most cases) with IDAs will require you to trim a bit off the  car to make it fit....