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Topic Review (Newest First)
07-22-2019 09:01 PM
jjjaffo
Quote:
Originally Posted by ericnova72 View Post
If the car retains 80% of the original flor pan, then from 11.49-9.90 just a 6 point roll bar is track legal, and that's the term I should have used instead of cage. Roll cage after 9.90 or if the car can exceed 135MPH 1/4 mile.
Stock driveshaft is just a piece of seamed muffler tube with yokes welded in, so they aren't real strong, just enough for the 200-ish HP of the stock motors that were in them.

Decent 496, 3.42 gear, and decent traction and getting faster than 11.50 shouldn't be that hard if you tune away at it, that was why I made the roll bar reference. I don't think it will make low 10's-9.90, but getting under 11.50 is a definite possibility.

You sure about that 4000 lbs weight?? Seems awful heavy, most of the G-body metric chassis '78-87 cars are relatively light...my step brothers '79 Monte Carlo is 3300lbs with aluminum wheels, a 383 SBC, Th-400, and a steel Sears roll around floor jack in the trunk! Nothing has been removed to lighten the car either, not an ounce. just the aluminum wheels and intake manifold.
Big Block is going to add a couple hundred lbs, but still shouldn't be anywhere near 4000 lbs.
I had the car weighed with me in it. All iron BBC except intake, turbo 400 trans, 1/2 tank of gas and my fat 330 pound butt in it. Came to just over 3900 pounds. Also steel wheels. Also, this car originally had a V-6 diesel in it. Not a typo, it was a V-6 diesel. Pretty rare I guess. Anyway I don't know if that makes a difference but it was a heavy little guy. Never even had to change front springs when the big block went in.
07-22-2019 01:40 PM
ericnova72
Quote:
Originally Posted by jjjaffo View Post
Never thought about the body to frame mounts. Yeah the rubber is totally junk. I also have factory motor mounts. Should I upgrade them and the tranny mount? Rear springs are weak and need to be replaced. Thinking Hotchkiss for the four link setup. Custom driveshaft needed to handle power? You say I might need a cage if I go to the track and hook up. I thought you only needed a cage if you broke into the 10s? I'm no expert on the subject of course but at almost 4000 pounds and a 3.42 gear I can't see it getting there. Am I way off base on that?
If the car retains 80% of the original flor pan, then from 11.49-9.90 just a 6 point roll bar is track legal, and that's the term I should have used instead of cage. Roll cage after 9.90 or if the car can exceed 135MPH 1/4 mile.
Stock driveshaft is just a piece of seamed muffler tube with yokes welded in, so they aren't real strong, just enough for the 200-ish HP of the stock motors that were in them.

Decent 496, 3.42 gear, and decent traction and getting faster than 11.50 shouldn't be that hard if you tune away at it, that was why I made the roll bar reference. I don't think it will make low 10's-9.90, but getting under 11.50 is a definite possibility.

You sure about that 4000 lbs weight?? Seems awful heavy, most of the G-body metric chassis '78-87 cars are relatively light...my step brothers '79 Monte Carlo is 3300lbs with aluminum wheels, a 383 SBC, Th-400, and a steel Sears roll around floor jack in the trunk! Nothing has been removed to lighten the car either, not an ounce. just the aluminum wheels and intake manifold.
Big Block is going to add a couple hundred lbs, but still shouldn't be anywhere near 4000 lbs.
07-21-2019 06:42 PM
Dfish1247 Depends on how wild you drive is how the rear end and transmission will do.

My car still has the 8.2" 10 bolt in it, when I have the money, I'll get a 9", still has a factory th400 as well, same deal there. Have a 3000 stall converter though, so that's different.


Depends on how wild you make it, same with any engine, is how fast it'll go. You can either get power from rpms, forced induction, or cubic inches. Guess which is easiest to live with on the street.
07-21-2019 05:43 PM
jjjaffo
Quote:
Originally Posted by ericnova72 View Post
Frame will handle the NA 496 and not give a problem, but potential handling and traction benefits are there if you were to box it. Just takes about 20' of 1/8" x 4" to 6" ?? flat bar steel welded over the opening. It's been a while since I measured one, I don't remember for sure what width flat bar is needed, you'd have to give that a quick check if you wanted to do it. Makes it more solid like the a-body convertible and El Camino frames from the 60's and mid 70's that came boxed from the factory.
At the very least I would plan to replace all the stock rubber body-to-frame mount bushings with polyurethane performance versions....the old rubber is sure to be dry rotted and loose. This will stiffen things up a lot. With good stiff bushings, the body and frame together help stiffen each other….with dead rubber they can't help each other. Poly bushings and boxed would be the top dog way to go to avoid any need for a roll bar on the street to keep it stiff. more of a sleeper performance mindset, and the way I'd do it.

Yeah, stock rear axle and stock control arms in the rear will either break(the rear axle) or flex and cause wheel hop(the stock arms), so I would plan to replace all that. Springs are probably worn out too.

Roll bar or cage won't be necessary to keep it together, but on sticky tires the motor will make enough steam the car will be fast enough that strip rules will likely require one if you plan more than 1 track day.

you can plainly see the open channel section I this picture:
Never thought about the body to frame mounts. Yeah the rubber is totally junk. I also have factory motor mounts. Should I upgrade them and the tranny mount? Rear springs are weak and need to be replaced. Thinking Hotchkiss for the four link setup. Custom driveshaft needed to handle power? You say I might need a cage if I go to the track and hook up. I thought you only needed a cage if you broke into the 10s? I'm no expert on the subject of course but at almost 4000 pounds and a 3.42 gear I can't see it getting there. Am I way off base on that?
07-21-2019 03:31 PM
ericnova72 Frame will handle the NA 496 and not give a problem, but potential handling and traction benefits are there if you were to box it. Just takes about 20' of 1/8" x 4" to 6" ?? flat bar steel welded over the opening. It's been a while since I measured one, I don't remember for sure what width flat bar is needed, you'd have to give that a quick check if you wanted to do it. Makes it more solid like the a-body convertible and El Camino frames from the 60's and mid 70's that came boxed from the factory.
At the very least I would plan to replace all the stock rubber body-to-frame mount bushings with polyurethane performance versions....the old rubber is sure to be dry rotted and loose. This will stiffen things up a lot. With good stiff bushings, the body and frame together help stiffen each other….with dead rubber they can't help each other. Poly bushings and boxed would be the top dog way to go to avoid any need for a roll bar on the street to keep it stiff. more of a sleeper performance mindset, and the way I'd do it.

Yeah, stock rear axle and stock control arms in the rear will either break(the rear axle) or flex and cause wheel hop(the stock arms), so I would plan to replace all that. Springs are probably worn out too.

Roll bar or cage won't be necessary to keep it together, but on sticky tires the motor will make enough steam the car will be fast enough that strip rules will likely require one if you plan more than 1 track day.

you can plainly see the open channel section I this picture:
07-21-2019 12:31 PM
jjjaffo
Quote:
Originally Posted by ericnova72 View Post
454 or 496 blown on pump gas.
-7.5-8.0:1 compression ratio, 6-8 psi boost. Will need forged steel crank and better than stock connecting rods, forged pistons flat top or dish depending on head combustion chamber size. Crank will need to have twin crank keyways for blower drive hub or harmonic balancer drive reliability.
-8-71 blower, a water/methanol supplement injection to help cool the mixture during boost, and a boost retard ignition, the injection and retard could allow the use of boost up to 10-11 psi on the street, twin 850 cfm carbs or 950's
-Aftermarket 12-bolt, Dana 60, or 9" will all work(but avoid a stock housing 12-bolt).
-TH-400, 4L80E, or aftermarket PowerGlide for the trans,(700R4/4L60-65-70 or TH-350 won't have a chance). Stall converter doesn't need to have real high stall but does need to be built to handle the amount of power put out, a $200-300 "2800 stall" is not going to live long, figure $800+ for the converter, 9.5 to 11.0" blower spec converter.
-DART/Brodix/AFR/ProFiler for heads, talk to both them and the blower company to find out the best spec for the use and power you want.
-Supercharger...Blower Drive Service, Mert LittleField Blowers are a couple that come to mind. but there are others out there. Not Weiand/Edelbrock/Holley
-2" headers and 3" exhaust would work, 2-1/4" headers 3.5" exhaust would be better.
-Don't forget a stout driveshaft, along with it really ought to have the frame boxed(it is open channel from just behind front tire to just before rear tire, a weak section that should be boxed shut. Probably should have a cage, minimum would be at least a rear half 4 point roll bar but that won't be legal without a door bar on the driver side if you even intend to go to the track.
- if staying with stock suspension in the rear, will need to be all aftermarket arms, and have all the frame mounting points reinforced.
-Radiator shouldn't be a big issue, these cars have a large core support area for radiator mounting. A good big aluminum core should do it.

Between engine parts, blower, and the parts for drivetrain, trans, fuel system, ignition and all the little bits you probably looking at $30,000.
motor parts is 8k in a stock block(another 3K aftermarket block), trans 2K, converter 1k, rear axle and suspension parts 3k, blower, carbs, water-meth, ignition 7-8k...and then you've got all the little things like roll bar, frame mods, wheels, tires, driveshaft, exhaust, radiator, waterpump and pulleys to fit with the blower drive in the way, fuel pump/lines/filters/regulators, tank sump or cell

Big power costs money...then beefing everything else up to that power standard costs as much or more....otherwise it just sits in the garage busted all the time if you try to take shortcuts.
Boy did you put everything into perspective in a quick hurry, LOL! So with that being said, what are the odds of the car staying together with a naturally aspirated 496? I know the rear end has to be replaced; that's just a given. But do I need a cage or box the frame? If I get a good tire on it and get it to hook up decent will I damage the frame by tweaking it all out of shape? I guess I need a reality check from the experts. I love the idea of hero power, but not at the expense of my safety! Money is not free flowing but there is usually a few hundred available at the end of every month and the car is safely tucked away in a shop. Time is on my side as I'm in no hurry. Actually right now I have more money than time due to working 60+ hours a week, LOL! So yeah, let's be more realistic about this build and figure it with a N/A 496 of around 500-530 horse power. I would imagine torque would be close to 550 lbft. Of course all dependent on how I build the engine. So, for a safe and pleasurable drive what key things do I need to pay attention to on the car itself? My only real experience with a heavy power to weight ratio was when I was 17 and I took the bone stock 2-bbl 351w out of my 77 LTD and put it in my 80 Pinto. An incredible undertaking and it wasn't as powerful as I'd hoped, but still damaged the frame and when you floored it you could watch the air cleaner shift almost two inches under the homemade scoop. I'd like to be several degrees safer than that!
07-21-2019 11:42 AM
Dfish1247
Quote:
Originally Posted by ericnova72 View Post
454 or 496 blown on pump gas.
-7.5-8.0:1 compression ratio, 6-8 psi boost. Will need forged steel crank and better than stock connecting rods, forged pistons flat top or dish depending on head combustion chamber size. Crank will need to have twin crank keyways for blower drive hub or harmonic balancer drive reliability.
-8-71 blower, a water/methanol supplement injection to help cool the mixture during boost, and a boost retard ignition, the injection and retard could allow the use of boost up to 10-11 psi on the street, twin 850 cfm carbs or 950's
-Aftermarket 12-bolt, Dana 60, or 9" will all work(but avoid a stock housing 12-bolt).
-TH-400, 4L80E, or aftermarket PowerGlide for the trans,(700R4/4L60-65-70 or TH-350 won't have a chance). Stall converter doesn't need to have real high stall but does need to be built to handle the amount of power put out, a $200-300 "2800 stall" is not going to live long, figure $800+ for the converter, 9.5 to 11.0" blower spec converter.
-DART/Brodix/AFR/ProFiler for heads, talk to both them and the blower company to find out the best spec for the use and power you want. -Supercharger...Blower Drive Service, Mert LittleField Blowers are a couple that come to mind. but there are others out there. Not Weiand/Edelbrock/Holley
-2" headers and 3" exhaust would work, 2-1/4" headers 3.5" exhaust would be better.
-Don't forget a stout driveshaft, along with it really ought to have the frame boxed(it is open channel from just behind front tire to just before rear tire, a weak section that should be boxed shut. Probably should have a cage, minimum would be at least a rear half 4 point roll bar but that won't be legal without a door bar on the driver side if you even intend to go to the track.
- if staying with stock suspension in the rear, will need to be all aftermarket arms, and have all the frame mounting points reinforced.
-Radiator shouldn't be a big issue, these cars have a large core support area for radiator mounting. A good big aluminum core should do it.

Between engine parts, blower, and the parts for drivetrain, trans, fuel system, ignition and all the little bits you probably looking at $30,000.
motor parts is 8k in a stock block(another 3K aftermarket block), trans 2K, converter 1k, rear axle and suspension parts 3k, blower, carbs, water-meth, ignition 7-8k...and then you've got all the little things like roll bar, frame mods, wheels, tires, driveshaft, exhaust, radiator, waterpump and pulleys to fit wit the blower dive in the way, fuel pump/lines/filters/regulators, tank sump or cell

Big power costs money...then beefing everything else up to that power standard costs as much or more....otherwise it just sits in the garage busted all the time if you try to take shortcuts.
See what I mean? Couldn't help it, too good not to give credit where it's due.
07-21-2019 11:36 AM
ericnova72
Quote:
Originally Posted by jjjaffo View Post
On the bigger is better theory, I have another Idea/question: What about putting a super charger on either the 454 or the 496? Actually I'm leaning towards the 496. Predator Carb Guru got me thinking When he talked about being crushed into the seat. I have always loved the look of a roots style blower on top of a big block- even though they are not the most efficient. This is unchartered territory for me as I've never built a blown engine. I want to run this for extended periods of time on the street so the combination has to be dead reliable. I'm looking to keep the intake charge temperature at a reasonable level so as not to need a cooler or worry too much about evil detonation. What is a safe 91 octane street friendly compression ratio? Safe boost level? What size blower to feed this thing? I assume dual carbs, what size? Reasonable cam? Do I need a boost referenced ignition system? My car is a G-body so I need a good radiator that fits and would cool this thing. I know I'll need a seriously beefed up transmission to handle this thing. Torque convertor recommendation? Because it will be street driven I don't want to go any higher than a 3.42 gear. Will a custom 12-bolt hold up or is this Ford 9-inch territory? I already have 2" super comp headers w/ 3 1/2" collectors, will these be enough? Will 3" exhaust get the job done? Like I said it's mostly street so will spend little time in the upper RPM range. I need real advise on this because I'm totally out of my element here. P.S. how about a good head recommendation?
454 or 496 blown on pump gas.
-7.5-8.0:1 compression ratio, 6-8 psi boost. Will need forged steel crank and better than stock connecting rods, forged pistons flat top or dish depending on head combustion chamber size. Crank will need to have twin crank keyways for blower drive hub or harmonic balancer drive reliability.
-8-71 blower, a water/methanol supplement injection to help cool the mixture during boost, and a boost retard ignition, the injection and retard could allow the use of boost up to 10-11 psi on the street, twin 850 cfm carbs or 950's
-Aftermarket 12-bolt, Dana 60, or 9" will all work(but avoid a stock housing 12-bolt).
-TH-400, 4L80E, or aftermarket PowerGlide for the trans,(700R4/4L60-65-70 or TH-350 won't have a chance). Stall converter doesn't need to have real high stall but does need to be built to handle the amount of power put out, a $200-300 "2800 stall" is not going to live long, figure $800+ for the converter, 9.5 to 11.0" blower spec converter.
-DART/Brodix/AFR/ProFiler for heads, talk to both them and the blower company to find out the best spec for the use and power you want.
-Supercharger...Blower Drive Service, Mert LittleField Blowers are a couple that come to mind. but there are others out there. Not Weiand/Edelbrock/Holley
-2" headers and 3" exhaust would work, 2-1/4" headers 3.5" exhaust would be better.
-Don't forget a stout driveshaft, along with it really ought to have the frame boxed(it is open channel from just behind front tire to just before rear tire, a weak section that should be boxed shut. Probably should have a cage, minimum would be at least a rear half 4 point roll bar but that won't be legal without a door bar on the driver side if you even intend to go to the track.
- if staying with stock suspension in the rear, will need to be all aftermarket arms, and have all the frame mounting points reinforced.
-Radiator shouldn't be a big issue, these cars have a large core support area for radiator mounting. A good big aluminum core should do it.

Between engine parts, blower, and the parts for drivetrain, trans, fuel system, ignition and all the little bits you probably looking at $30,000.
motor parts is 8k in a stock block(another 3K aftermarket block), trans 2K, converter 1k, rear axle and suspension parts 3k, blower, carbs, water-meth, ignition 7-8k...and then you've got all the little things like roll bar, frame mods, wheels, tires, driveshaft, exhaust, radiator, waterpump and pulleys to fit with the blower drive in the way, fuel pump/lines/filters/regulators, tank sump or cell

Big power costs money...then beefing everything else up to that power standard costs as much or more....otherwise it just sits in the garage busted all the time if you try to take shortcuts.
07-21-2019 11:31 AM
Dfish1247 What's your budget? Not just the cost of the motor, but having to build the car not to disintegrate around it(roll cage, trans, rear end,etc) The supporting cast is just as if not more expensive than the engine itself.

I asked about this myself and got talked out of it, way too much of a project that I wanted to tackle, including the money. Mainly the money as I'm not rich.

Have you ever ridden in a blown big block car? I have and it is a violent experience, you'd get used to it, but the first time was like getting hit in the back by a freight train, not very funny watching the gas gauge move just as fast as the speedometer if your the owner either.

Figure on using an 8-71, more volume with less rotor speed means less heat, less heat=less chance of detonation.

Call dyers blowers, I spent over an hour getting most of the deal explained to me, never tried to sell me a thing either. Other than someone who owns one, they can fill you in.
07-21-2019 09:43 AM
jjjaffo On the bigger is better theory, I have another Idea/question: What about putting a super charger on either the 454 or the 496? Actually I'm leaning towards the 496. Predator Carb Guru got me thinking When he talked about being crushed into the seat. I have always loved the look of a roots style blower on top of a big block- even though they are not the most efficient. This is unchartered territory for me as I've never built a blown engine. I want to run this for extended periods of time on the street so the combination has to be dead reliable. I'm looking to keep the intake charge temperature at a reasonable level so as not to need a cooler or worry too much about evil detonation. What is a safe 91 octane street friendly compression ratio? Safe boost level? What size blower to feed this thing? I assume dual carbs, what size? Reasonable cam? Do I need a boost referenced ignition system? My car is a G-body so I need a good radiator that fits and would cool this thing. I know I'll need a seriously beefed up transmission to handle this thing. Torque convertor recommendation? Because it will be street driven I don't want to go any higher than a 3.42 gear. Will a custom 12-bolt hold up or is this Ford 9-inch territory? I already have 2" super comp headers w/ 3 1/2" collectors, will these be enough? Will 3" exhaust get the job done? Like I said it's mostly street so will spend little time in the upper RPM range. I need real advise on this because I'm totally out of my element here. P.S. how about a good head recommendation?
07-18-2019 04:59 PM
jjjaffo
Quote:
Originally Posted by lmsport View Post
even grocery getter engines get hydraulic rollers now, it's about durability.
and don't worry about the RPM, hydraulic rollers will turn at least 7k comfortably. I am a fan of Howards HR lifters, zero issues with them. For solids/racing Isky is the only choice. Isky of PAC springs for everything.
Yes even grocery getters get them. And yes, you can wind them up pretty high. However, the heavy valve train and stiff springs can create bleed down issues in the upper RPMs resulting in less lift and duration. Not saying it will, but can. The average grocery getter has a pretty lazy cam in them designed to go hundreds of thousands of miles. As we all know performance cams tend to push the envelope of reliability and require high quality parts to make them live. This is especially true for flat tappet cams. Isky makes great camshafts and PAC springs are some of the best out there. I also have had good luck with Lunati and Comp cams. There's lovers and haters for all of them. For solid flat tappet cams on the street I tend to get custom cams from comp because they tend to have the milder profiles I'm looking for. I had another thread on this site where people questioned my choosing mild cams for the compression I run. Here's the deal: I like the highest cranking compression safely possible for pump gas. The higher that number, within reason, the more torque the engine produces. As has been said many times cams must be matched to the right compression ratio. My little 408 BBC runs factory closed chamber iron heads, 9.7 to 1 compression, 185 PSI cranking compression, terrible .070" quench and too much timing and it runs like an animal all day long on 91 octane pump gas. No detonation at all. This is with a 270 magnum hydraulic flat tappet timed 6* advanced. The only problem is the heads with the small 2.06 intake valves make the engine peak out at about 5 grand. Since the lift is only .510" I think I can up the peak a few hundred RPMs with a comparable solid flat tappet and gain about .035" lift after lash. It's just not worth the expense to put quality heads on this little guy because I have a 496 build in mind. Till the money becomes available to make that a reality I continue to tinker with my baby rat. And help others with their builds.
07-18-2019 11:06 AM
lmsport even grocery getter engines get hydraulic rollers now, it's about durability.
and don't worry about the RPM, hydraulic rollers will turn at least 7k comfortably. I am a fan of Howards HR lifters, zero issues with them. For solids/racing Isky is the only choice. Isky of PAC springs for everything.
07-18-2019 10:09 AM
jjjaffo
Quote:
Originally Posted by 2001Blazer4x4 View Post
To me LMSport is obviously talking about a solid roller (at 8000 rpm), which is really the ultimate performance cam type.

Cams are much more than lift and duration. It's all about valve timing. You can choose a comparison cam to prove pretty much whatever you want to sell.

On the street, there is no disadvantage to a hydraulic roller in general - other than the high cost. But on the strip the hydraulic roller can be quite RPM limited due to the heavy valve train.

Flat tappet solid has more potential to make more horsepower than a hydraulic roller by being able to spin to a much higher RPM.

Flat tappet hydraulic brings up the rear in performance
Yes, that is pretty much what I found too. I have always liked solid flat tappet cams because what you see is what you get, all your lift and duration at lash. I find that even on the street if you are careful in your selection, and don't mind the noise, the torque and power of a solid flat tappet is way more fun than a hydraulic. And, with a good spring you can run up through the gears a littles higher than a hydraulic as the torque curve doesn't seem to drop off as fast resulting in a little more usable horse power.
07-18-2019 09:48 AM
2001Blazer4x4 To me LMSport is obviously talking about a solid roller (at 8000 rpm), which is really the ultimate performance cam type.

Cams are much more than lift and duration. It's all about valve timing. You can choose a comparison cam to prove pretty much whatever you want to sell.

On the street, there is no disadvantage to a hydraulic roller in general - other than the high cost. But on the strip the hydraulic roller can be quite RPM limited due to the heavy valve train.

Flat tappet solid has more potential to make more horsepower than a hydraulic roller by being able to spin to a much higher RPM.

Flat tappet hydraulic brings up the rear in performance
07-18-2019 09:35 AM
lmsport the roller versus ft debate is pretty short for me--rollers are more durable and can provide more power.
Rick at Isky told me many years ago that his flat tappets made basically the same power in the engines I was building (8k RPM oval, 350cid, 700hp) as the rollers. For street use, GM went roller for durability with modern oils and a little horsepower.
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