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Old 03-26-2008, 10:54 PM
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Originally Posted by cncbird
What are you going to run for headers?
I also run a BBC in a 2000 Z/28 and the previous owner found that Hooker Super Comp BBC hedders off a 70's/80's Camaro worked with a little massaging to the floor. They are probably a touch small on the primaries for a big inch application, but they have worked well so far and you don't feel too bad when you grind them after a wheelie since they are dirt cheap compared to a Kooks or Lemmons.
Old 03-26-2008, 11:36 PM
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Alot of people will also tell you that they run faster with smaller primary headers when they started with larger. I know one guy that did this and his car screamed when he went with smaller headers, mine are SBC diamaiter (can't remember size) and they are on a big cam 468. I also have hooker super comps, yeah third gen but they seem to work for both thirds and fourths.


On the cams, LOTS of people that are on the bottle will tell you to NOT go with a nitrous cam unless you are spraying a 300+ shot and spraying A LOT. If you want to just spray a smaller shot every now and then then go with a N/A cam.

When I build mine up more this winter I MAY go with a Nitrous cam but it will be over a 300 shot if I do, right now its at a 300 and Ill keep it a N/A cam if I keep it at that, if I go more and get to the track mor ethen we will see about going to a N20 cam. If the rods are free go for them, but like you said just don't overbuild it.


Keeping the stock hood is cool but remember the HEAT!!!!!!! I have a 3 inch cowl and the engine runs pretty cool even in traffic, the cowl lets a lof of hot air out. Even with your ram air hood, air gets it just fine but what about it getting out, now a cowl ram air hood would work great and be cool.

Last edited by JUICED96Z; 03-26-2008 at 11:48 PM.
Old 03-27-2008, 01:32 AM
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N/A, but I do have plans to put a spray bar in the manifold and hit it with a 150-225 wet shot. That won't happen until I get the Midwest 9" though, I going to gamble with the 10 bolt so I can get it out to the track. Obviously I will be babying it out of the hole, but it should be fun none the less.
I didn’t see anything about transmission, suspension, ect. It is obvious you are investing a significant amount of time and money in your engine. No offense, but with an engine like that, build the car from the back to front rather that front to back. Start with a rear-end, suspension, driveshaft, transmission that will support the HP & torque you will have. I would guess @ 825 HP you are going to have 650 – 700 ft/lbs of torque. I think your 10 bolt will let you down right away even you do baby it out of the hole.
Old 03-27-2008, 01:45 AM
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^ It may not. Tiago pushed his hard as hell with over a 1000rwhp on his old twin 70mm, forged 346m, six speed car. It never actually blew up he decided to switch it for safety's sake. It's all in how you drive it. My friend yanked the front wheels a good three feet at least ten times on 275 radials with his car before it killed the stock posi.
Old 03-27-2008, 02:02 AM
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Originally Posted by Beaflag VonRathburg
^ It may not. Tiago pushed his hard as hell with over a 1000rwhp on his old twin 70mm, forged 346m, six speed car. It never actually blew up he decided to switch it for safety's sake. It's all in how you drive it. My friend yanked the front wheels a good three feet at least ten times on 275 radials with his car before it killed the stock posi.
There is allways the exception but in most cases it will blow pretty quick on big power levels. Also depends on what RPM you are launching at, you can have 1,000RWHP and ease it out of the hole then beat on it and I am sure it will last a long time.

BTW, Have you taken that class again yet???
Old 03-27-2008, 07:48 AM
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Originally Posted by cncbird
What are you going to run for headers?
Headers are Hooker 2455's. They were 150 a set and I have cut the #7 primary so I can loop it and then go straight down to clear the firewall. I will have to bend them to get more clearance around the k-member, but they are a nice alternative I'm willing to work with in the beginning rather than buying a $1,200 set of headers. BTW they are 2" primaries, but I'm thinking on my next set I'll get 2 1/4".
Old 03-27-2008, 07:58 AM
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Originally Posted by 98 Silver Bullet
I didn’t see anything about transmission, suspension, ect. It is obvious you are investing a significant amount of time and money in your engine. No offense, but with an engine like that, build the car from the back to front rather that front to back. Start with a rear-end, suspension, driveshaft, transmission that will support the HP & torque you will have. I would guess @ 825 HP you are going to have 650 – 700 ft/lbs of torque. I think your 10 bolt will let you down right away even you do baby it out of the hole.
The idea was to make the car appear stock so basically the car is stock. Uses stock hood, stock airbox, it has a T56, but it will be built later on after I find out what I'm looking at. Basically along with everything else I don't want to over build and get a Viper tranny for $2,500 to handle some pretty small numbers that a $1,500 or so tranny would handle just fine. I do have the McLeod Steel Street Twin already so I'm good there.

Rear end is a little different, I would rather have confidence that I can launch hard so I'm getting a Midwest 9", I just have to decide what width I want. I would like to go 3" shortened with 15x10 with 5" backspace, I think that would be awesome, but I'm not sure if I want to do that or get a stock width rear and run 15x10 with 8" backspace so I can still run the stock WS6 wheels when I'm not racing so I can have once again that stock appearance and then just slap on the drag wheels when I go to the track.

I like the second option because it fits the theme, but the look of the first option is soooooooo nice.
Old 03-27-2008, 02:26 PM
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I think on pump gas it will make about 720 fwhp and around 690 tq. Either way that's what a 555? Should be a good running motor, good thing is even with a cam that seems big when you look at it on paper the power will come in pretty early.
Old 03-27-2008, 03:34 PM
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I hope you're wrong

When I was doing my research a crate 572 puts out those numbers with a 254 duration HR cam with .632 lift and small 315cc heads out of the box with 9.6:1 CR. I'm hoping that a slightly larger SR cam with more lift and ported heads and intake running 11:1 will perform better than that....or at least that's my goal.

If I wanted to make big numbers I would have used the other set of Wiseco pistons I had that put me around 14:1 compression and gotten the 360cc heads. That would have been a screamer, but I couldn't drive it on the street to show it off or run it on pump gas.
Old 03-27-2008, 03:59 PM
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Just talked to the builder on the phone and was shooting the **** and while I don't have the balance card obviously he told me the rod weight was 885g and the Pistons/Pins/Rings were 778g. Total bobweight was 2,489g, which he said was fairly light. I don't have a lot of experience with rotating weights so I take his word for it, but wondered what you guys thought.
Old 03-27-2008, 04:07 PM
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Gm's 572 12-1 motor makes 720 hp, and runs a solid roller 266 / 274 with .714 lift, I think you have a better set of heads, but the rest is close to the same, not to try to down your build or anything but I just honestly don't think it will see 825 fwhp.

I would think it would make a little over 700 hp with a peak around 6500. Yes the cam looks big on paper but when you go with 555 inches it's on the mild side.

Just my .02, I hope I am wrong and you do make 825 hp, that would be awesome on pump gas N/A.
Old 03-27-2008, 04:22 PM
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Engine masters did an actual dyno test of the street 572 here and it was advertised at 620 I believe and came out right around 700, I'm sure the race version is more than 720.

http://www.popularhotrodding.com/eng...tor/index.html
Old 03-27-2008, 04:25 PM
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Originally Posted by ulakovic22
Just talked to the builder on the phone and was shooting the **** and while I don't have the balance card obviously he told me the rod weight was 885g and the Pistons/Pins/Rings were 778g. Total bobweight was 2,489g, which he said was fairly light. I don't have a lot of experience with rotating weights so I take his word for it, but wondered what you guys thought.
Your size flat top piston is about 685 grams, plus the rings. A Lunati pro billet rod weighs about 840 grams, so the stuff you have is about average for BBC stuff.

What length rod are you running 6.135 or 6.385.

A light weight setup would run an aluminum rod or titanium rod, I beam rods that big are on the heavy side compared to an h beam rod which would be around 780 grams for your size.

On the other hand you're only going to rev the motor around the 6,500 rpm range so either way you still have parts that will work good with what you're doing.
Old 03-27-2008, 04:29 PM
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Originally Posted by ulakovic22
Engine masters did an actual dyno test of the street 572 here and it was advertised at 620 I believe and came out right around 700, I'm sure the race version is more than 720.

http://www.popularhotrodding.com/eng...tor/index.html
They also have a 2" primary and 4" exhaust, I think you'll lose a little with the smaller primary and exhaust, plus you have less cubic inches. Either way I'm interested to see. It's hard to know for sure when companies over and underrate power ratings for sales purposes.

One thing for sure it's going to be a blast to drive.
Old 03-27-2008, 04:41 PM
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I'm running 2" primaries and 3.5" X pipe exhaust.

Yeah the less cubic inches is a small problem, but when comparing a 355 to a 383, which has a higher CID variance, most of the time they make close to the same peak power but the 383 has more area under the curve which I understand will probably be the case here.

I'm excited to have it all come together too so I can keep moving and get everything finished. I had the project stall for a long time waiting on Wiseco to come out with their low dome pistons. Now I'm waiting on McLeod to ship out the freakin' flywheel/clutch assembly so I can get the RA balanced. Once that's done I should hopefully get things moving again with the fuel system, gauges and wiring while I wait for the intake to be ported.
Old 03-27-2008, 05:28 PM
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Why did you decide to go fuel injected vs, carburated?
Old 03-27-2008, 06:02 PM
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Easy tuning and hood clearance are the two main reasons. It takes a lot of hacking to get a carb and air cleaner to fit under there. Also when tuning a carb/dist set up I didn't want to constantly be pulling the cap to change springs and carb to change jets and secondary springs, etc.

Aside from I guess I could make the argument that at the track it's easier to adjust for track conditions, better fuel economy, more precise fuel metering and distribution, blah blah blah.
Old 03-28-2008, 04:37 AM
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With most modern race carbs I don't think you have to pull the carb to change the jets, just the bowls.

A lot of the faster guys even with something like coil on plugs end up going to distributors even if its a belt driven one and not all distributors have springs

Your other arguments are pretty legit but you can't get both economy and performance, its either one or the other or a little of both.

Anything BBC will NOT get good gas mileage, my 468 gets about 10mpg cruising. I would not expect to get a lot more out of you motor honsetly.

Its a pump gas motor (10.1) but does not really like the pump gas, it will tollerate sunoco 94 but thats about it.

Bumping the compression way up this winter.
Old 03-28-2008, 10:55 AM
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Originally Posted by JUICED96Z
With most modern race carbs I don't think you have to pull the carb to change the jets, just the bowls.
I don't think you do either, but with half the carb sitting under the cowl it would rather difficult to get to. Would probably be easier to just pull it off all together.

Originally Posted by JUICED96Z
A lot of the faster guys even with something like coil on plugs end up going to distributors even if its a belt driven one and not all distributors have springs
I am going to run a distributor but one without springs, no coil on plug or anything like that. I have a crank trigger and I'm getting a dizzy with cam sync.

Originally Posted by JUICED96Z
Your other arguments are pretty legit but you can't get both economy and performance, its either one or the other or a little of both.

Anything BBC will NOT get good gas mileage, my 468 gets about 10mpg cruising. I would not expect to get a lot more out of you motor honsetly.

Its a pump gas motor (10.1) but does not really like the pump gas, it will tollerate sunoco 94 but thats about it.
I know it won't get decent mileage, I was actually thinking something around 6-8 mpg, but I think it would be better with injection versus carb. I'm sad to hear though that with pump gas and 10:1 you are having problems....are you running iron heads or aluminum? I don't like how that sounds cause I figured I would be safe around 11:1. That's what I run in my Camaro.
Old 03-28-2008, 12:07 PM
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The carb is not too bad to work on, and once you get it dialed in, you won't be changing jets that often. Another solution is to run a 1050CFM 4150 style carb with a 4500 base plate. That will bring the float screw and the bowl out from under the cowl. Quick Fuel told me that unless you are running a heads-up class, the slight difference in performance would not matter.

For distributors, I just have a billet MSD and that works fine; I just have to take the cap off to get it in the car.






To get all of the clearance, we had to do this...









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