Will that compression run on pump gas?
[Z06] High compression/nitrous 447 C5Z CMS build thread
Thread Starter
Racer
Joined: Mar 2010
Posts: 435
Likes: 1
High compression/nitrous 447 C5Z CMS build thread
I'm currently in the process of finishing up my 447 build. The shortblock is almost finished being put together and the heads should be on their way back soon. I am having all the work done by Cunningham Motorsports. Ever since I saw how good his C6Z always ran on NA 427, I have been wanting a big cube NA motor too. Here's what's going into this build.
C5R block
WCCH LS7 heads angle milled to 58cc Compression will be 14.5:1
Wiesco Forged 4.155 bore piston
Compstar Forged Crank 4.125 stroke
Compstar Forged H-Beam 6.125 rods
Fast 102mm Intake Manifold (Hand ported in shop)
4 solenoid Nitrous Outlet Direct port (Will be jetted for 250+shot)
2" American Racing Headers with Cat-less X-Pipe
Walbro 465 E85 Fuel Pump
MSD Boost-a-pump
Can't wait for all this to be done and see what kind of power I can get out of this set-up. I wanted a set-up that could dabble in just about every type of car event. I really like taking the car out on the road course so I wanted to stay NA for that but there are times I like to take it out for Airstrip/ drag racing events and the nitrous set up will add to that to give it that extra power when I want it. I'll be updating the thread as things start coming together a bit more.
C5R block
WCCH LS7 heads angle milled to 58cc Compression will be 14.5:1
Wiesco Forged 4.155 bore piston
Compstar Forged Crank 4.125 stroke
Compstar Forged H-Beam 6.125 rods
Fast 102mm Intake Manifold (Hand ported in shop)
4 solenoid Nitrous Outlet Direct port (Will be jetted for 250+shot)
2" American Racing Headers with Cat-less X-Pipe
Walbro 465 E85 Fuel Pump
MSD Boost-a-pump
Can't wait for all this to be done and see what kind of power I can get out of this set-up. I wanted a set-up that could dabble in just about every type of car event. I really like taking the car out on the road course so I wanted to stay NA for that but there are times I like to take it out for Airstrip/ drag racing events and the nitrous set up will add to that to give it that extra power when I want it. I'll be updating the thread as things start coming together a bit more.
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Thread Starter
Racer
Joined: Mar 2010
Posts: 435
Likes: 1
Apologies for taking so long to get an update on this. The short block has been back from the machine shop for a few weeks now but haven't had a chance to take good pictures. The LS7 heads just got back from WCCH after their amazing port work. I just ordered the Holley black krinkle valve covers and the big Ron Davis radiator with oil cooler built it. The car already has a Doug Rippie oil cooler on it but I'll feel better having two coolers on this car for the track use.
I'm currently in the process of port patching the FAST Intake manifold to the heads so there's a nice smooth flow of air. Pretty time consuming process but should be well worth the extra hp gained! We are looking at taking the old motor out on the 9th of August so look for more updates as things start wrapping up. I'll try and get some pics tomorrow or early next week of everything.
Here's two pictures I did take with my phone right before I started port-matching the intake.
I'm currently in the process of port patching the FAST Intake manifold to the heads so there's a nice smooth flow of air. Pretty time consuming process but should be well worth the extra hp gained! We are looking at taking the old motor out on the 9th of August so look for more updates as things start wrapping up. I'll try and get some pics tomorrow or early next week of everything.
Here's two pictures I did take with my phone right before I started port-matching the intake.
Thread Starter
Racer
Joined: Mar 2010
Posts: 435
Likes: 1
oh also one more thing, for right now we are just going to stick with my single nozzle setup for the nitrous. We decided to back off on spraying anything bigger than a 150 for now. With how high the compression is and running stock casting heads I don't want to take a chance of lifting the heads from all the cylinder pressure. Maybe down the road I will swap to a set of Brodix or something and then up the shot but for now I'll be happy with how it's going to be.
Thread Starter
Racer
Joined: Mar 2010
Posts: 435
Likes: 1
It is a street car that I occasionally take to road race or airstrip events. As far as smog? Ha either A: I get a hook up on smog or B: I don't care about smog since I won't be in the state of California much longer.
Drifting
Joined: Apr 2003
Posts: 1,389
Likes: 10
From: Jacksonville FL
Good to see your making progress. Are you planning to run a stand alone fuel system for the nitrous? With the new power you probably won't be needing to spray it to get your heart rate up for a while anyway.
Melting Slicks
Joined: Aug 2010
Posts: 2,855
Likes: 78
From: Sammamish WA
WA Events Coordinator
I left CA last year, but last I heard they were moving to reading only Codes off of OBD-II cars in 2014. Thats what they do here in WA in the Counties that require smog testing.
Racer
Joined: Apr 2010
Posts: 389
Likes: 25
Racer
Joined: Apr 2010
Posts: 389
Likes: 25
Yes but there is still the visual inspection and with certain headers and no CATS there would likely be issues. Regardless the build looks interestin. Best of luck to the OP.
Melting Slicks
Joined: Aug 2010
Posts: 2,855
Likes: 78
From: Sammamish WA
WA Events Coordinator
Well, when I lived there I had a Smog shop, they never looked under the hood of my '95 M3, and it was very far from Stock visually. But it passed smog which is the important thing....
Thread Starter
Racer
Joined: Mar 2010
Posts: 435
Likes: 1
I was going to do a stand alone fuel cell but Ryne has another idea instead. He explained it to me when we first talked about it but I don't remember the details so I'll get back to you on it. I know we will be basically modifying the hat for another line and basically adding an inline pump to it if I remember correctly. No point in running a stand alone cell really since I won't be running any different fuel other than E85.