Building a 408 stroker
- Thread starter 75dart
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Dead End Kid
Well-Known Member
There's a nice build-up for a 408 over in the archive's. You will need to give more info. to get a good response to what to build. Here's just a start:
1. What gears/trans/stall converter?
2. Percent street/strip use.
3. Heads:
A. What pistons?
B. The Edelbrocks are a great "compromise" and a good choice out-of-the-box for street use. Just remember, you will give up about 1 point static compression due to the fact they are aluminium.
4. Torque vs. h.p. vs. rpm range
5. the big one - how much $$$ do you want to spend?
This is no way a difinative list, but should start the dialogue
Mac.
1. What gears/trans/stall converter?
2. Percent street/strip use.
3. Heads:
A. What pistons?
B. The Edelbrocks are a great "compromise" and a good choice out-of-the-box for street use. Just remember, you will give up about 1 point static compression due to the fact they are aluminium.
4. Torque vs. h.p. vs. rpm range
5. the big one - how much $$$ do you want to spend?
This is no way a difinative list, but should start the dialogue
Mac.
Good post Dead End,
Heres another general clue that you should give that only YOU the person doing the engine have an idea on in addition to the above post.
This applies to everybody, not just our member 75dart or any body new at building engines.
................................Remember, we need info...................................
How much power do you want to make?
Is torque a factor in this? (Just because it's a stroker doesn't mean you can ignore this)
How fast in the 1/4 or 1/8 is it you want to go?
By the way, welcome to the site 75Dart
Thats the $64.000 everyone asks and they haven't got a clue on what it takes to figure it out.
Heres another general clue that you should give that only YOU the person doing the engine have an idea on in addition to the above post.
This applies to everybody, not just our member 75dart or any body new at building engines.
................................Remember, we need info...................................
How much power do you want to make?
Is torque a factor in this? (Just because it's a stroker doesn't mean you can ignore this)
How fast in the 1/4 or 1/8 is it you want to go?
By the way, welcome to the site 75Dart
moper
Well-Known Member
Dead End Kid said:
I'd alter the pecking oder:
#1. Total Budget
#2. What do you have to start with?
#3. How do you use the vehicle 90% of the time?
#4. Gear ratio
#5. Convertor
The parts choices depend on honest answers to all of these. So, tell us what you have, and what you need out of it.
I have a 1975 dart sport and i will only drive the car maybe 50 percent of the time. It will be mostly street use but sometimes Ill take it to the strip. I have about a grand after i buy the stroker kit. I want to run iron heads I just dont know what ones to run. Im going to put 3.91 and run a 2000 stall converter
Sooo, basically were talking about a street strip car that see the track once in awhile, while beating up on those other guys inbetween runs to the strip going from light to light.
Street beast. I like it. A couple more questions if you please. Bear with me.
Do you allready have a 2000 stall converter and what are the tires dimentions. Er, the metric size;s like 255/60/15's or a slick sizes like 27 X 10.
Is the car all steel? Wondering about weight.
I ask this because you allready mentioned a stall converter. And gears. This puts a limit on cam size. If your willing to change converters, the cam size could go up.
It's all combo related.
Lastly, do you want a Hyd. Mech. or a roller cam.
The heads are your call. A dual plane is great for the street. RPM or Stealth. Cyl. heads could be iron ported stockers and they'll perform great. Edel. heads are an option, but should still have work done to them for best results.
Street beast. I like it. A couple more questions if you please. Bear with me.
Do you allready have a 2000 stall converter and what are the tires dimentions. Er, the metric size;s like 255/60/15's or a slick sizes like 27 X 10.
Is the car all steel? Wondering about weight.
I ask this because you allready mentioned a stall converter. And gears. This puts a limit on cam size. If your willing to change converters, the cam size could go up.
It's all combo related.
Lastly, do you want a Hyd. Mech. or a roller cam.
The heads are your call. A dual plane is great for the street. RPM or Stealth. Cyl. heads could be iron ported stockers and they'll perform great. Edel. heads are an option, but should still have work done to them for best results.
I dont have the converter or the gears yet. The car is going to be steel maybe a fiberglass hood. I probably will go with 265/60/15 or 265/75/15. Im going 2 go with the hyd. cam. What stall convertor should I use and what gears. I wasnt sure how big I should go with the cam because i want it streetable but still be able to take it to the strip.
mopowermatt
mopowermatt
what size headers???? collector?? How about an X pipe?
moper
Well-Known Member
If you have "$1000 over the price of the kit" means not mugh money...Does that cover the machine work too? Around me, that isnt enough to have it machined and assembled, nevermind the heads too. What do you have for parts on hand? The stroker kits may still need balancing, and dont include things like oiling system parts, cam bearings, block hardware, timing set, fuel pump, all the little things that make an engine run. An honest budget of $2500 plus the rotating kit will get you a decent long block, but a long block is a long ways from a running engine. A good 360 will cost less to build than a 416 or 408, and give many of the same benefits...
IMO, What I would use with your combo would be the Comp Cams XE274H. This cam should provided monster torque and decent hi RPM power. Within the cams (& heads) limits. You should be able to drive anywhere at anytime with great low speed torque and enuff power on tap to really get you going well.75dart said:
More bable;
Heres the thing on the converter. If you had a 2000 stall, the cams would be in a bracket size of , lets just say for/in example; 210 - 220 degress of duration @ .050. Putting in a bigger cam, lets just say the extreme other end, 260-270 degress @ .050 would not work great because the converter would not have enuff stall to allow the engine to reach where the cam starts to make power and it would make the car a slug down low. Tire size has an effect to a small degree unless the combo is really out of wack.
That takes care of duration. Now how much lift can the heads support? Also how well the ports are balanced. Thats also key in getting a cam zeroed in. As well as how much clearance you have in the piston. But since you don't have heads, the sky is still open. What I'll do is recomend a few Crane & Comp Cams that will work well in the basic combo info provided. More lift is possible with some of these cams or you can order a custom ground cam for basicly the same price, a few pennys more. These are just examples of what could be used.
An example of cam(s) that you could use would be;
Not great to good balance in the heads,
Low rpm side, XE 274 H
HIgher rpm XE 284 H or Lunati's 304A3LUN 231-239 @ .050 .514 .536 lift.
If you know that the heads flow well with higher lifts;
low, XE 275 HL
Higher, XE 285 HL
A better balanced head can also use a singal pattern cam, though most prefur dual no matter what. An example wold be a Comp Magnum cam like there 292H (high side) or the 280H (low side) or a Crane 232 @.050 with .504 lift. Luntia has a 235 @ .050 with .507 lift (PN 07402)
All would work well with the 3.91 you wanted to use. Notice how there all aroundthe same area of duration.
Also, being the engine is stroked larger, a larger engine tends to swallow up a large cam. The cam seems smaller due to engine size.
I like the XE 274H for stock ported heads that do not have a ton of work in them. If I had heads that had a lot of work, extensive porting and high flow numbers, the XE275HL I'd go after.
My 360 4spd car has 4.10's and a 27 inch tire. I like a heavier cam in a 4spd. (Personal taste) and would go with the XE285HL with my ported heads.
Sorry for the run on babble.
D-mailman
Well-Known Member
75DART, yes go with the 360. Not anymore expensive than 340 to build and much more torque. H.P. mostly be the same. Good luck, Terry.
It would be cheaper to build a 360 over a stroker built on the cheap. Do what your wallet demands. <LOL>75dart said:
For the stroker, you'll need the expense of the crank, clearance machine work of the block and more expensive pistons.
On the 360, you have it all allready except the pistons.
With the larger engine, to unleash it's potentail, better heads are required. This is also an added expense if your seeking to get the max out of it vs. a 360.
Old tyme X,J,O etc.. or the newer 308's. The newer Magnum heads do well. I'd opt for a (Magnum) R/T head from MoPar, all heads mentioned bowl ported at a min.
moper
Well-Known Member
For budgetary purposes, I'd run 587s, 308s, or pretty much anything you can get cheap. Magnums are nice, but IMO are not big enough in any stock form except the MP commando versions to feed that stroke. As Rumble said, all should have a performance valve job done, and bowl blending/gasket matching done to them. Running iron heads on such a long stroke, I would go larger on the cam shaft for the 408.
For the 360, really again, any head will work with the same prep. The Magnums would also work for the 360...
For the 360, really again, any head will work with the same prep. The Magnums would also work for the 360...
Just to chip in...
I stroked the 340 in my '73 Roadrunner with Ma's cast crank. I used Eagle I beam rods and Diamond pistons (a weight move). I spent something like eleven hundred bucks in getting the heads worked (and they do). The big choice was in the cam. I went with a custom solid from Comp using two tight lash Ford profiles for a dirt track car. It's .540 on the intake and .549 on the exhaust. The duration is 242 intake and 247 exhaust @ .050. It's ground on a 108 seperation +4. I use Comps Magnum rockers and Smith Bros pushrods. (I am going to buy another set and chrome plate them to hang over the mantle, I love them to death.)
So, with my 3.23 open rear and 727 tranny, I had Continental build a converter. I would reccommend them to anyone. Don't ask me what the stall is, I told 'em what I had, they built it, I forgot to check or ask what the stall was, it works great. (Sorry, I am getting old).
The results? This thing pulls HARD. It has a torque band like a table. The Idle is rowdy, but not unliveable, due in part to the extra cubes. I still use my factory power brake booster with absolutely no ill affects. It sounds like nothing else out there and I will swear by this combo. I am currently running a Holley Strip Dominator single plane, but I am considering swapping over to a RPM Air Gap. We'll see....
The down side....
This thing cost about five g's to put together. Now bear in mind, I had to tear it down twice. Why? The first time, after initial break in and dialing, it tossed the crank on the seven mile trip home. The mains just flat went away. I had the crank tested and found that they were too soft. FYI, Scat makes the cast cranks for Ma' Mopar. Although admitting nothing wrong, Scat did sell me a replacement for a little over a hundred bucks. Three months after that, I lost a lobe on the cam. Most likely my fault, who knows, it's just cars. I am now tearing down again after four years for oil consumption. Diamond likes big clearances on their pistons, I guess I will have to work on this a bit more. Oh, that and it killed my 8 and 3/4 rearend. (Needed a 3.91 posi anyhow.) For the record, with the Thermoquad and highway gears, this thing managed 18mpg on the highway.
So there is my story on the stroker. Would I reccommend it? Hell yes. Would I do it again? In a New York second. (Maybe with Edelbrock heads.) This time out, I am punching it up to 421, adding TTI headers, and the posi. I'll let you know when it's done. Might be awhile, I am playing with my Valiant's suspension and brakes right now, so I have to concentrate the money thing.
Revhendo
I stroked the 340 in my '73 Roadrunner with Ma's cast crank. I used Eagle I beam rods and Diamond pistons (a weight move). I spent something like eleven hundred bucks in getting the heads worked (and they do). The big choice was in the cam. I went with a custom solid from Comp using two tight lash Ford profiles for a dirt track car. It's .540 on the intake and .549 on the exhaust. The duration is 242 intake and 247 exhaust @ .050. It's ground on a 108 seperation +4. I use Comps Magnum rockers and Smith Bros pushrods. (I am going to buy another set and chrome plate them to hang over the mantle, I love them to death.)
So, with my 3.23 open rear and 727 tranny, I had Continental build a converter. I would reccommend them to anyone. Don't ask me what the stall is, I told 'em what I had, they built it, I forgot to check or ask what the stall was, it works great. (Sorry, I am getting old).
The results? This thing pulls HARD. It has a torque band like a table. The Idle is rowdy, but not unliveable, due in part to the extra cubes. I still use my factory power brake booster with absolutely no ill affects. It sounds like nothing else out there and I will swear by this combo. I am currently running a Holley Strip Dominator single plane, but I am considering swapping over to a RPM Air Gap. We'll see....
The down side....
This thing cost about five g's to put together. Now bear in mind, I had to tear it down twice. Why? The first time, after initial break in and dialing, it tossed the crank on the seven mile trip home. The mains just flat went away. I had the crank tested and found that they were too soft. FYI, Scat makes the cast cranks for Ma' Mopar. Although admitting nothing wrong, Scat did sell me a replacement for a little over a hundred bucks. Three months after that, I lost a lobe on the cam. Most likely my fault, who knows, it's just cars. I am now tearing down again after four years for oil consumption. Diamond likes big clearances on their pistons, I guess I will have to work on this a bit more. Oh, that and it killed my 8 and 3/4 rearend. (Needed a 3.91 posi anyhow.) For the record, with the Thermoquad and highway gears, this thing managed 18mpg on the highway.
So there is my story on the stroker. Would I reccommend it? Hell yes. Would I do it again? In a New York second. (Maybe with Edelbrock heads.) This time out, I am punching it up to 421, adding TTI headers, and the posi. I'll let you know when it's done. Might be awhile, I am playing with my Valiant's suspension and brakes right now, so I have to concentrate the money thing.
Revhendo
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