i need a high revving race application 400 small block mopar. i have a good block thats complete and runs but its going into a chrysler newport derby car. i dont have a huge budget. i want it to rev high but i want it to last more than 1 race. any help greatly appreciated.
dman16
I'm curious what you are going to do w/a "high revving race application 400"? Is this for a particular class or some such? Can the engine be larger, or is it limited to 400 CID?
I ask, because there are ways to get good power out of a 400 MOPAR engine, but it usually involves going bigger, like stroking it to 451 or larger (much larger in some cases).
The 451 has a (relatively speaking) short stroke for it's size so revving it isn't out of the question by any means- but it can get costly because the rotator and valve train needs to be able to stand up to the stress.
Some more details of what you are after will help.
I ask, because there are ways to get good power out of a 400 MOPAR engine, but it usually involves going bigger, like stroking it to 451 or larger (much larger in some cases).
The 451 has a (relatively speaking) short stroke for it's size so revving it isn't out of the question by any means- but it can get costly because the rotator and valve train needs to be able to stand up to the stress.
Some more details of what you are after will help.
I think that you would be better off using a 360 and stroking it. I think that the 400 may take to much time to build power as it has a fairly long stroke. Also the added weight of the big block may be a hindrance.
The 400bb and 440 rb make excellent drag motors do to the massive torque that you get but I would think that if you needed to get on and off the gas as you would in any circle racing that a quicker revving engine along with proper rear end gear selection would be the way to go.
Just my 2 cents.
If all you have is the 400, I would concentrate on the gearing. You are not going to be able to easily or cheaply make it rev freely. You would have to lighten the recipricating mass (pistons, flywheel, rods, etc) to get it to rev quicker.
Vic
The 400bb and 440 rb make excellent drag motors do to the massive torque that you get but I would think that if you needed to get on and off the gas as you would in any circle racing that a quicker revving engine along with proper rear end gear selection would be the way to go.
Just my 2 cents.
If all you have is the 400, I would concentrate on the gearing. You are not going to be able to easily or cheaply make it rev freely. You would have to lighten the recipricating mass (pistons, flywheel, rods, etc) to get it to rev quicker.
Vic
The 400 B does not have a long stroke- it's VERY oversquare at 4.34" bore x 3.38 stroke. This is less than a 267/305/350 SBC.
Even w/the 440 stroke length crank, it's then the same stroke as a 383/400 SBC @ 3.75", except the displacement jumps to ~450 cid- w/the 3.75" stroke and a 0.060" over 440 piston, or what ever it is MOPAR guys use these days.
If I were gonna race a MOPAR, it would be an LA engine, though. No need to make it any more difficult than it has to be, IMO.
Even w/the 440 stroke length crank, it's then the same stroke as a 383/400 SBC @ 3.75", except the displacement jumps to ~450 cid- w/the 3.75" stroke and a 0.060" over 440 piston, or what ever it is MOPAR guys use these days.
If I were gonna race a MOPAR, it would be an LA engine, though. No need to make it any more difficult than it has to be, IMO.
Found this on another forum
Not a 400, but worth considering:
First we'll start with a 318 block (re builder) as they are plentiful, then we'll get a 360 crank and turn the mains down to 318 specs. We are going to use the factory 6.123 rods, and low compression 318 pistons which are 1.72 compression height. Next we are going to align hone and deck the block to clean and square deck all 4 corners. This is more info on what to do and not priced as price can vary. So now we have a block that measures 9.570 after decking .030. As most used blocks are generally out .020 to .030 from core settling and thermal cycles, some may be taller as they are only castings. Now this is where we are 9.570 actual deck height less the rod length, and the compression distance, and stroke. Half of 3.58 is 1.79 on stroke.
9.570-1.79=7.780 minus rod length of 6.123= 1.657 less the compression distance of 1.72= .063 above the deck. Now we'll take a corteco head gasket of .055 which now we have .008 above the gasket. Or for racing use a .022 mopar gasket and have .033 more compression for a total of .041 above the gasket.
Next we'll go to the heads, for a 349 CI we'll need the 360 heads to get enough port volume and air flow. By my calculations we'll need 166 cc's of port volume and 266 cfms to supply enough air and we'll be using the 1.88 intake valves and 1.60 exhaust valves to help keep the port velocity up. This is fairly easy to get when mildly ported. As for the chambers they have been in the .095 to .105 in chamber depth stock, at the area where the quench would be. So now we have a positive deck of .041 with the gasket in place, or .008 depending on which gasket is being used. In this case we'll use the thinner gasket so we'll be .041 above the deck. Now the deck is .095 less the positive deck of .041 and we now have a quench of .051 so we'll deck the heads to true them up, generally this takes .010 to .012 so now we have a total quench of .039 to .041 which is what most would like to have as total quench. This now yields 12.21:1 this is why this is a race setup, the thicker head gasket will yield about 11.5:1. If it doesn't take as much to deck the heads or the block then this will change to a lower compression and be more street-able.
Next we'll go to the camshaft, for our example were using a comp cams .540 /300 drag race cam with 255 @ .050. For this cam the pistons will have to be notched, so we notched them .200 as the pistons are forged and are .400 thick. This is about as far as you can go safely. We'll be using 1.6 ratio rockers so the lift is .576 but the lash is .026 and we have to subtract .010 for the loss of valve lift due to the grind for mopars. Now we have a actual net lift of .540. So with the valve reliefs we should have .100-.130 valve to piston clearance depending on the gasket thickness.
Next we'll go to the intake manifold, this I leave up to the end user for what they want. But for our application we used the M-1 intake as we had it, from another engine. And we'll top it off with a Holley carb 850 cfm with 83 and 88 jets and no power valves.
So now to some this up we have a 318 with a 360 crank and stock rods and pistons of the forged type. Stock type heads with work done and a M-1 intake and a street type headers. A good cam and valve train and oiling system to support this type of engine. The preliminary tests have shown 578 HP @ 6500 and 507 TQ @ 5000, and 506 FT. lbs. @ 4500. So it has a nice broad torque curve. Even in lessor trim it should still have over 500 HP and 450 in torque and be street able.
Not a 400, but worth considering:
First we'll start with a 318 block (re builder) as they are plentiful, then we'll get a 360 crank and turn the mains down to 318 specs. We are going to use the factory 6.123 rods, and low compression 318 pistons which are 1.72 compression height. Next we are going to align hone and deck the block to clean and square deck all 4 corners. This is more info on what to do and not priced as price can vary. So now we have a block that measures 9.570 after decking .030. As most used blocks are generally out .020 to .030 from core settling and thermal cycles, some may be taller as they are only castings. Now this is where we are 9.570 actual deck height less the rod length, and the compression distance, and stroke. Half of 3.58 is 1.79 on stroke.
9.570-1.79=7.780 minus rod length of 6.123= 1.657 less the compression distance of 1.72= .063 above the deck. Now we'll take a corteco head gasket of .055 which now we have .008 above the gasket. Or for racing use a .022 mopar gasket and have .033 more compression for a total of .041 above the gasket.
Next we'll go to the heads, for a 349 CI we'll need the 360 heads to get enough port volume and air flow. By my calculations we'll need 166 cc's of port volume and 266 cfms to supply enough air and we'll be using the 1.88 intake valves and 1.60 exhaust valves to help keep the port velocity up. This is fairly easy to get when mildly ported. As for the chambers they have been in the .095 to .105 in chamber depth stock, at the area where the quench would be. So now we have a positive deck of .041 with the gasket in place, or .008 depending on which gasket is being used. In this case we'll use the thinner gasket so we'll be .041 above the deck. Now the deck is .095 less the positive deck of .041 and we now have a quench of .051 so we'll deck the heads to true them up, generally this takes .010 to .012 so now we have a total quench of .039 to .041 which is what most would like to have as total quench. This now yields 12.21:1 this is why this is a race setup, the thicker head gasket will yield about 11.5:1. If it doesn't take as much to deck the heads or the block then this will change to a lower compression and be more street-able.
Next we'll go to the camshaft, for our example were using a comp cams .540 /300 drag race cam with 255 @ .050. For this cam the pistons will have to be notched, so we notched them .200 as the pistons are forged and are .400 thick. This is about as far as you can go safely. We'll be using 1.6 ratio rockers so the lift is .576 but the lash is .026 and we have to subtract .010 for the loss of valve lift due to the grind for mopars. Now we have a actual net lift of .540. So with the valve reliefs we should have .100-.130 valve to piston clearance depending on the gasket thickness.
Next we'll go to the intake manifold, this I leave up to the end user for what they want. But for our application we used the M-1 intake as we had it, from another engine. And we'll top it off with a Holley carb 850 cfm with 83 and 88 jets and no power valves.
So now to some this up we have a 318 with a 360 crank and stock rods and pistons of the forged type. Stock type heads with work done and a M-1 intake and a street type headers. A good cam and valve train and oiling system to support this type of engine. The preliminary tests have shown 578 HP @ 6500 and 507 TQ @ 5000, and 506 FT. lbs. @ 4500. So it has a nice broad torque curve. Even in lessor trim it should still have over 500 HP and 450 in torque and be street able.
ok, I'll ask again.
Do you mean derby as in demolition derby or is this a circle track car?
Son, you have to realize YOU know what you're going to do with the car, whereas I have no clue and have no idea what a finale car is.
Is the car to be used on a circle track or a figure 8 track or in a free for all demolition event?
Do you mean derby as in demolition derby or is this a circle track car?
Son, you have to realize YOU know what you're going to do with the car, whereas I have no clue and have no idea what a finale car is.
Is the car to be used on a circle track or a figure 8 track or in a free for all demolition event?
techinspector1 said:
Tech....I think he said it here... :drunk: :drunk:
I think he's planning on smashing it up on regular bases...dman16 said:
Maybe it's just me. All I ever ask of anyone is to give me the plan and the details. The word "derby" doesn't mean a damned thing to me. Could be a demolition derby, a circle track derby, a figure 8 derby, a sand derby, a parking lot derby, a mud bog derby, a hill climb derby or a CIRCLE-JERK derby for all I know. You can smash it up in any of those venues.NEW INTERIORS said:Tech....I think he said it here... :drunk: :drunk:
I think he's planning on smashing it up on regular bases...
NEW INTERIORS, no disrespect meant toward you at all.
You would be totally wasting your time and money to mod the engine for higher revving horsepower. The top speed that you will ever reach can't be much over 50 mph, if you're doing it right, so put the time and money into all the little tricks and such that go into a derby-winning car. You will never see a winning derby car/driver w/a hot rod engine. There's just no point in it. You want something to live under duress- to live when overheated, low on oil pressure, etc.
Around here I believe they refer to that type of racing as Enduro racing. A cross between street stocks and demo derby. They race for like 50 laps with no cautions.
And those guys want good engines. Yeah, the car gets beat up but they just beat them back into shape. If the drive train is built well, they don't have to spend time on the whole package each weekend getting ready for the next race. Is that what you are doing dman? If you tell us exactly what you are doing, we can help you better. Tells us man lol. What kind of track surface will you be running on? Clay, buttfault, loose dirt, muddy, icyengineczar said:
engineczar said:
I think you have a complete mis-understanding the Enduro or cruiser class in dirt track racing. It is not a demo derby at all, although it appears to be because of the skill of many of the drivers and the lack of mods that can be made. The enduro class is an entry level class that can be be done on the cheap. Building a godd hobby stock car can be financially out of reach for many people. A good enduro car can be built well under $1000.
I raced my 2001 crown vic for two years in New Mexico and still would be if they did not close down the track. Our average raqce night consisted of one to two heats of 10 laps and then a 20 lap A and B main. If any car was in a bad accident or spun we had the yellow come out just as any other class. We usually had between 30 to 45 cars per night show up. As a class we put more money and fans in the seats than the other class. Due to bad management the track run by the indians was shut down and the equipment sold off. Here is a link to the general rules of the class.
http://www.westcoastenduro.org/rules.html
Actually I don't have a complete mis-understanding thank you. I've built a few engines for local Enduro racers so I know how serious some of them can be.BugRod said:
My reference was so that others can zero in on what I believe the original poster was getting at. When you hear the word "derby" thrown into the conversation you immediately think demo derby as opposed to any actual racing.
dman16, I don't know if your organization adheres to the rules posted by BugRod or not, but there are a couple in there that you may want to pay attention to...to wit...
"The intent of the engine rule is to keep it stock with no more than 9:1 compression"
"compression test not to exceed 180# per cylinder."
" Must have a minimum of seventeen (17) inches of manifold vacuum @ 1000 rpm."
"NO STROKER MOTORS. Stock intake and exhaust manifolds only."
"The intent of the engine rule is to keep it stock with no more than 9:1 compression"
"compression test not to exceed 180# per cylinder."
" Must have a minimum of seventeen (17) inches of manifold vacuum @ 1000 rpm."
"NO STROKER MOTORS. Stock intake and exhaust manifolds only."
www.kitsapdestructionderby.com/ has info for you guys. rules, picture of cars and the track or go to you tube and search kitsap destruction derby. http://www.youtube.com/watch?v=44SnOfmtB_Y thats a link to a good video of what ill be doing. ill maybe do 10 laps at most and run the car for a whole 10 minutes tops per race.
Looks like fun. I'll give you my take on it just from watching the figure 8 video.
From a driveline standpoint, I'd start with the biggest motor I could bolt in the car. As you come around the outside tire and gun it across the middle of the track to the next inside tire, you'll need all the low end torque the motor can muster and that means starting with lots of cubic inches and using a short cam to make max grunt. That's a very short track drag race and I don't see the advantage of a high-winding motor in which you have to use a lot of cam that kills low end torque.
I might be thinkin' starting with a 440 and using a cam matched to the static compression ratio (based on the available fuel) that will nose over at around 5000 rpm's and make max torque around 3500-4000. I'd use a 727 auto trans with a 3000-3500 stall converter and a rear gear that would allow max revs at the inside tire on the next corner. Finding out the mph these faster cars are going when getting to the next inside tire will allow you to do some back-figuring and choosing the right gear and tire size. That would be my low-buck approach. If I had some extra money to throw at the car, I'd be thinkin' stroker crank for even more grunt.
I see in the rules that you can run 2-wheel brakes. I wouldn't do it. You're gonna need all the braking power you can muster to avoid other cars in the middle of the "X". You can't win if you can't finish.
I know very little about circle track setups, but with the little I do know, I'd be setting the front end camber at several degrees negative on each side and maybe extending the upper control attachment point at the spindle up some to improve camber gain on bump. I've seen where these extensions are commercially available. At the end of each heat, I'd be measuring the temperature of the tire tread from one side of the tread to the other. This will tell you where to set the camber and tire pressure. I used to do that when my son was racing go-karts on a road track and we had the car to the point that it would corner like it was on rails.
I might be all wet, but that's just my take on it from watching the video.
From a driveline standpoint, I'd start with the biggest motor I could bolt in the car. As you come around the outside tire and gun it across the middle of the track to the next inside tire, you'll need all the low end torque the motor can muster and that means starting with lots of cubic inches and using a short cam to make max grunt. That's a very short track drag race and I don't see the advantage of a high-winding motor in which you have to use a lot of cam that kills low end torque.
I might be thinkin' starting with a 440 and using a cam matched to the static compression ratio (based on the available fuel) that will nose over at around 5000 rpm's and make max torque around 3500-4000. I'd use a 727 auto trans with a 3000-3500 stall converter and a rear gear that would allow max revs at the inside tire on the next corner. Finding out the mph these faster cars are going when getting to the next inside tire will allow you to do some back-figuring and choosing the right gear and tire size. That would be my low-buck approach. If I had some extra money to throw at the car, I'd be thinkin' stroker crank for even more grunt.
I see in the rules that you can run 2-wheel brakes. I wouldn't do it. You're gonna need all the braking power you can muster to avoid other cars in the middle of the "X". You can't win if you can't finish.
I know very little about circle track setups, but with the little I do know, I'd be setting the front end camber at several degrees negative on each side and maybe extending the upper control attachment point at the spindle up some to improve camber gain on bump. I've seen where these extensions are commercially available. At the end of each heat, I'd be measuring the temperature of the tire tread from one side of the tread to the other. This will tell you where to set the camber and tire pressure. I used to do that when my son was racing go-karts on a road track and we had the car to the point that it would corner like it was on rails.
I might be all wet, but that's just my take on it from watching the video.
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