School me on rotating assemblies... school me on cams...

[aarons04cobra]

So long story short, my cobra belonged to a close friend who passed away two years ago. His goal was to build this car to drop 4 digit power on the dyno on a PD blower. I am in the process of trying to make his dream come true. I do not intend to drive the car on the streets under full boost. I am mainly looking to get my 1k on the dyno and then run the car on lower boost for the street. The car will see some track time but no more then 5-10 1/4 mile track days a season and maybe 1 o r 2 half mile events.

Low down on the car: built SRA, t56 magnum, mac LT's, MM coil overs, no cats, no egr, no a/c. keeping the power steering.

I intend to run the car on e85 and swap over to a pump gas / torco tune if i take it on any longer cruises. The car is getting a cage while the motor is being built. I was originally thinking i wanted to run a 4.0L whipple but after further research, I am thinking a 3.4 crusher and a shot of nitrous will be the safer bet to get my dyno number. I am open to suggestions, however I have zero interest in going to a turbo/auto setup like I'm sure some will suggest. The heads are being ported and re-threaded. The block is getting bored .20 over. All ARP hardware.

My questions pertain more to what cams and rotating assemblies I should purchase. I have a local engine builder that I have great faith in assembling the engine once all parts arrive. I am removing the motor from the car this week.

I see on lethal performance these rotating assembly kits. But I am unsure what will be best. I have heard mixed thoughts on the eagle kits for high hp applications.

http://www.lethalperformance.com/ea...w-forged-crankshaft-4cc-pistons-020-over.html

http://www.lethalperformance.com/ea...-forged-crankshaft-17cc-pistons-020-over.html


i am open to any input but would mainly

Is there a rotating assembly kit that comes with everything that anyone could recommend?

What type of pistons would be best for my application? "dished, flat top, etc"

What cams would be best?

I have heard I would be fine with the stock crank, but im not sure I want to take the risk. I was going replace it anyway just to be safe. Thoughts?

Whats rods would be best?

open to any other suggestions.

 

[jrgoffin]

Check out Gibtec for billet pistons. Awesome bang for the buck. Tons of info in this build thread:

http://www.modularfords.com/threads/236857-Aluminator-Gibtec-Build

 

[01yellercobra]

Friend of mine is running a Whipple 3.4 on a stock displacement engine. Stock crank and rods with upgraded pistons. The heads are fully worked over though. I think it's about 26psi, but the timing was soft from what I remember. He made 790 to the tires with that set up. And there's Comp stage 3 cams. I'm sure a custom cam would be a better choice for a similar price.

A lot of people say for the big power stay away from stroker set ups. Piston side loading and all that.

 

[Livernois Motorsports]

So long story short, my cobra belonged to a close friend who passed away two years ago. His goal was to build this car to drop 4 digit power on the dyno on a PD blower. I am in the process of trying to make his dream come true. I do not intend to drive the car on the streets under full boost. I am mainly looking to get my 1k on the dyno and then run the car on lower boost for the street. The car will see some track time but no more then 5-10 1/4 mile track days a season and maybe 1 o r 2 half mile events.

Low down on the car: built SRA, t56 magnum, mac LT's, MM coil overs, no cats, no egr, no a/c. keeping the power steering.

I intend to run the car on e85 and swap over to a pump gas / torco tune if i take it on any longer cruises. The car is getting a cage while the motor is being built. I was originally thinking i wanted to run a 4.0L whipple but after further research, I am thinking a 3.4 crusher and a shot of nitrous will be the safer bet to get my dyno number. I am open to suggestions, however I have zero interest in going to a turbo/auto setup like I'm sure some will suggest. The heads are being ported and re-threaded. The block is getting bored .20 over. All ARP hardware.

My questions pertain more to what cams and rotating assemblies I should purchase. I have a local engine builder that I have great faith in assembling the engine once all parts arrive. I am removing the motor from the car this week.

I see on lethal performance these rotating assembly kits. But I am unsure what will be best. I have heard mixed thoughts on the eagle kits for high hp applications.

http://www.lethalperformance.com/ea...w-forged-crankshaft-4cc-pistons-020-over.html

http://www.lethalperformance.com/ea...-forged-crankshaft-17cc-pistons-020-over.html


i am open to any input but would mainly

Is there a rotating assembly kit that comes with everything that anyone could recommend?

What type of pistons would be best for my application? "dished, flat top, etc"

What cams would be best?

I have heard I would be fine with the stock crank, but im not sure I want to take the risk. I was going replace it anyway just to be safe. Thoughts?

Whats rods would be best?

open to any other suggestions.

Well it looks like you have a lot going on there. If your after solid reliable 4 digit rear wheel #'s we do NOT recommend a iron 2 bolt block especially in a .020" over.
The proper way to do this would be with a sleeved 3v block.
If the car is at full weight running a o-ring/ receiver groove and copper head gasket is a recipe for success launching hard on a sticky tire.
As far as rotators go, at that power level you will want to put together a custom one. No off the shelf stuff if your after durability.
The o.e. Cobra crank will be fine power rating wise but that depends on its condition. It would seem a shame to build a new big power engine and not go larger bore and stroke as the dollars are not that much different in the end unless you go billet on the crank.
-custom piston (dish or flat top would be based off of the crank and compression choice)
-AP stainless ring set
-U.S. heavy wall wrist pins
-Billet i-beam conn rods
-reworked cobra crank or aftermarket stroker
-coated bearings
-main studs
-2000 head studs
full block prep
full cylinder head prep
billet gear oil pump
good oil pan
quality damper
camshafts should be ground for the combo and installed with the proper lash and gears
professional assembly by a modular specialist

Are those mac headers large enough primary tubes for 1000 wheels with a big huffer?

We can always recommend combos and components to people but you need to make sure the parts match up with the goals and budget. Otherwise you will have a expensive paperweight/door stop.

 

[cj428mach]

https://www.svtperformance.com/foru...000hp-whipple-terminator-on-the-dyno.1091656/

 

[MalcolmV8]

First very sorry about your friend, it's nice that you're continuing his build.

Since you're building the motor the motor it makes your goal so much more attainable. Well easier I should say.
I built a 10.5 SCR motor with flat top pistons. I had -1.64 CC intake reliefs which are .150" and my ring lands moved down .050" for stronger ring lands. That combo with stock .036" head gaskets makes 10.5 CR. Had I left the ring lands alone it would have been closer to 10.7. To give you a guide line.

Heads were hand ported by a local guy. Not the greatest job in the world but it worked. I've since had them re-ported by Livernois for this summer.
I had cams too. Initially the Comp stage 3s which are 238/240. It got complicated because I was having a lot of cam related issues which turned out to be the boost bypass valve actuator from low vacuum conditions caused by the cams.
I then had some custom grinds made 228/233 but my problems persisted until I figured out the vacuum / boost bypass valve issue. Not to get side tracked but my point is I don't know which set of cams would have been better due to all of that.

Anyways that combo with some good headers, 1 7/8" long tubes and a full 3" exhaust with a 2.9 Whipple Crusher made well over 1k to the wheels. I was spinning that blower to 30 PSI.
Fuel was true E85 ~ E86 as tested. It came out the pump from a local gas station.

I was plagued with lower pulleys breaking left and right and after fighting that issue for a while I got rid of the big blower and went with a 2.3 TVS.

Even with that tiny TVS at only a peak of 24 PSI the car still made 800 whp at 6k RPMs and I wrapped it to 7500 RPM. The little TVS makes some torque too. 640 ft/lb at only 3k RPMs and by 4k RPMs over 700 ft/lbs and climbing.

All that was on stock rods with ARP 2000 bolts. Some have said I was on borrowed time and others seem to think it would have lived forever.

This winter I decided to step things up and have gone with domed pistons putting me at 11.5 SCR. I also got the heads re-done by Livernois and mentioned above so I while I was at it I went ahead and threw in some Molnar rods for piece of mind. Perhaps over kill but they're such good bang for the buck and so incredibly strong it made sense.

So a good recipe for hitting your goal is going to be bump the compression, use E85 or race fuel and let the motor breath. No restrictions on air going in or out. You'll hit the goal with a 2.9 Whipple but if driven hard you'll be breaking lower pulleys like I did so be warned. I believe the issues comes from the very quick wrapping RPMs of the high compression motor. It's a lot of inertia to be speeding up and down at very rapid rates.

Perhaps lower compression motor with big blower and some nitrous to hit goal.
Or
High compression motor with smaller blower and some nitrous.

 

[aarons04cobra]

Well it looks like you have a lot going on there. If your after solid reliable 4 digit rear wheel #'s we do NOT recommend a iron 2 bolt block especially in a .020" over.
The proper way to do this would be with a sleeved 3v block.
If the car is at full weight running a o-ring/ receiver groove and copper head gasket is a recipe for success launching hard on a sticky tire.
As far as rotators go, at that power level you will want to put together a custom one. No off the shelf stuff if your after durability.
The o.e. Cobra crank will be fine power rating wise but that depends on its condition. It would seem a shame to build a new big power engine and not go larger bore and stroke as the dollars are not that much different in the end unless you go billet on the crank.
-custom piston (dish or flat top would be based off of the crank and compression choice)
-AP stainless ring set
-U.S. heavy wall wrist pins
-Billet i-beam conn rods
-reworked cobra crank or aftermarket stroker
-coated bearings
-main studs
-2000 head studs
full block prep
full cylinder head prep
billet gear oil pump
good oil pan
quality damper
camshafts should be ground for the combo and installed with the proper lash and gears
professional assembly by a modular specialist

Are those mac headers large enough primary tubes for 1000 wheels with a big huffer?

We can always recommend combos and components to people but you need to make sure the parts match up with the goals and budget. Otherwise you will have a expensive paperweight/door stop.

Is there a phone number I can contact you guys at? Maybe we could talk about having you put together a price quote for me? feel free to PM me.

 

[aarons04cobra]

First very sorry about your friend, it's nice that you're continuing his build.

Since you're building the motor the motor it makes your goal so much more attainable. Well easier I should say.
I built a 10.5 SCR motor with flat top pistons. I had -1.64 CC intake reliefs which are .150" and my ring lands moved down .050" for stronger ring lands. That combo with stock .036" head gaskets makes 10.5 CR. Had I left the ring lands alone it would have been closer to 10.7. To give you a guide line.

Heads were hand ported by a local guy. Not the greatest job in the world but it worked. I've since had them re-ported by Livernois for this summer.
I had cams too. Initially the Comp stage 3s which are 238/240. It got complicated because I was having a lot of cam related issues which turned out to be the boost bypass valve actuator from low vacuum conditions caused by the cams.
I then had some custom grinds made 228/233 but my problems persisted until I figured out the vacuum / boost bypass valve issue. Not to get side tracked but my point is I don't know which set of cams would have been better due to all of that.

Anyways that combo with some good headers, 1 7/8" long tubes and a full 3" exhaust with a 2.9 Whipple Crusher made well over 1k to the wheels. I was spinning that blower to 30 PSI.
Fuel was true E85 ~ E86 as tested. It came out the pump from a local gas station.

I was plagued with lower pulleys breaking left and right and after fighting that issue for a while I got rid of the big blower and went with a 2.3 TVS.

Even with that tiny TVS at only a peak of 24 PSI the car still made 800 whp at 6k RPMs and I wrapped it to 7500 RPM. The little TVS makes some torque too. 640 ft/lb at only 3k RPMs and by 4k RPMs over 700 ft/lbs and climbing.

All that was on stock rods with ARP 2000 bolts. Some have said I was on borrowed time and others seem to think it would have lived forever.

This winter I decided to step things up and have gone with domed pistons putting me at 11.5 SCR. I also got the heads re-done by Livernois and mentioned above so I while I was at it I went ahead and threw in some Molnar rods for piece of mind. Perhaps over kill but they're such good bang for the buck and so incredibly strong it made sense.

So a good recipe for hitting your goal is going to be bump the compression, use E85 or race fuel and let the motor breath. No restrictions on air going in or out. You'll hit the goal with a 2.9 Whipple but if driven hard you'll be breaking lower pulleys like I did so be warned. I believe the issues comes from the very quick wrapping RPMs of the high compression motor. It's a lot of inertia to be speeding up and down at very rapid rates.

Perhaps lower compression motor with big blower and some nitrous to hit goal.
Or
High compression motor with smaller blower and some nitrous.

Wow, Your build is extremely impressive. Honestly I didn't think I would stand a chance at getting my number on a 2.9 whipple.
I was thinking I needed to leave the lower stock for the 3.4 "to avoid snapping lower pulleys like you had mentioned. I'm going to do some more research about everything you just said. I'll be in touch again soon with more questions once i educate myself a little more. thank you very much for your input!!!

 

[Livernois Motorsports]

Is there a phone number I can contact you guys at? Maybe we could talk about having you put together a price quote for me? feel free to PM me.

PM sent