SB Road Racing/Nascar/Sprint Car/Reving BUDGET BUILD

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SRT_DSTRHOLC

SRT_DSTRHOLC

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HI guys,

Please take kindly to the title as it's an attention grabber to get some of the old heads in here to help out.

I will clear the air before we get that one guy in here, my plan is to build a 73 Duster Multi purpose car that I can drive on the street/weekend/Road Race (laguna, sears point, willow) etc.

I want to do this from the ground up and instead of throwing in the Gen3 hemi I have right away, I want to do a budget build to R&D from the ground up using what Mother Mopar has already made. I will have a 6 speed TR6060 with a shortened 5th and 6th gear for the trans and then a 8 3/4 with 4.10 SureGrip. The car the engine will be in will be around 3000 lbs.

My "IDEA" is to get a stock 318-360 LA/Magnum and push the limits on her and really see what breaks and what doesn't, but before I go cowboy on this. I wanted to bring in the voices that have been doing this longer than I have to maybe guide my route on what would be the better base engine to work with.

What I want to do or had in mind was starting with a stock engine, running it and seeing what she does and then slowly mod the engine and track the progress for R&D. Eventually I would like to help others in this MOPAR world like most of you have done for me, but I figure what would be better than a ground up journal build tracking a base engine build.

Today everyone wants to go fast and we all have been guilty of throwing parts to go fast or say we make this and that number, but I wanted to take it back and maybe be someone who says "****, I did that with a stock bottom end 318 and this is what we did to survive or this is what we ran into."

So I know that I may not be the first to do this, but I really want the challenge of taking the high road and testing on the road, not on a dyno.

So I hope any advice would or guidance would help..



Right now I have access to a 69 318 which I believe made 230hp and 340tq or I could look into a bare block 340 or a magnum 318/360 from the yard.

I'd like to go the cheapest route as many people starting off here won't have the budget or knowledge to go any other route. Plus a lot of the information I grew up learning from y'all is stored WAY BACK in the archives of this website.


SO Here is to the budget builders...
 
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318 LA block (budget friendly), 920 closed chamber heads (from a 273)
RV type cam, 600 cfm carb, w/Edelbrock Performer intake, cheap long tube headers. 65'
 
Plymouth 65 said:
318 LA block (budget friendly), 920 closed chamber heads (from a 273)
RV type cam, 600 cfm carb, w/Edelbrock Performer intake, cheap long tube headers. 65'
Click to expand...
Seems like you may have done something like this before? haha
 
I'm actually building that exact engine. Still looking for the heads locally. 65'
 
Actually, I don't have any plans for the engine. Just putting it together for something to do. Most of the parts were collected over the years. Short block has about 10K miles on it and looks great inside. 65'
 
I say you start with a magnum 360 instead of an LA318 and choke it down with terrible flowing 273 heads. You said you wanted to go cheap then, instead of building a bottom end you could mill the heads to get more compression and throw a cam in it and go!! CHEAP!!
 
Plymouth 65 said:
Actually, I don't have any plans for the engine. Just putting it together for something to do. Most of the parts were collected over the years. Short block has about 10K miles on it and looks great inside. 65'
Click to expand...
haha, so when you recommended the build to me above, is that what your engine was going to do or were you just putting an engine build out there in general? Because now without any context, I am not sure what that engine would be good for lol
 
plymouth67 said:
I say you start with a magnum 360 instead of an LA318 and choke it down with terrible flowing 273 heads. You said you wanted to go cheap then, instead of building a bottom end you could mill the heads to get more compression and throw a cam in it and go!! CHEAP!!
Click to expand...
Correct, I did say this. Also, looking for something that will have a good high RPM limit in the end. So whatever engine I start with, it would be good for it to have a good ending point without having to switch blocks in order to make the power or RPM's.
 
The intended purpose of the build was for a high torque truck application, think towing. 65'
 
Plymouth 65 said:
The intended purpose of the build was for a high torque truck application, think towing. 65'
Click to expand...
Got it. Low end umph. But, doesn't that mean that it's not a very top end kind of power? I will clarify in the above post, but this car will be around 3000lbs
 
Yes, you are correct. Cam selection is due to lower compression and stock stall converter. You really have to look at the complete drivetrain. High RPM power can be achieved but you'll need higher compression, bigger rear gears and a higher stall converter. Typically, not budget friendly. 65'
 
Plymouth 65 said:
Yes, you are correct. Cam selection is due to lower compression and stock stall converter. You really have to look at the complete drivetrain. High RPM power can be achieved but you'll need higher compression, bigger rear gears and a higher stall converter. Typically, not budget friendly. 65'
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Understood. As mentioned in the original post. I have 4.10 rear gears and a 6 speed. I don't need a lot of power to start with 300-400hp in the higher 6-7k range if possible to do on a budget or with stock parts would be the goal.

I know that closed chambered 302 heads could get the compression up and then throw in a thinner head gasket.



I am looking for a path at starting line that that I can follow to end goal, but enjoy the process of the build instead of an entire engine build and being done with it. If that makes sense.

I want to hot rod the car and find out what it takes step by step to get to the end goal from a stock engine.
 
SRT_DSTRHOLC said:
I want to do this from the ground up and instead of throwing in the Gen3 hemi I have right away, I want to do a budget build to R&D from the ground up using what Mother Mopar has already made. I will have a 6 speed TR6060 with a shortened 5th and 6th gear for the trans and then a 8 3/4 with 4.10 SureGrip.
Click to expand...
Why go this route?? Perhaps I'm not fully understanding your plan but allow me to provide a counterpoint to what I think you're suggesting. You're basically saying in your statement above that you're ultimately going to go Gen III so why waste time and money on a middle step? Yes, the hemi is going to require different exhaust, fuel system, wiring, accessories, etc. which adds up quick. But if you have to obtain all those parts now for the small block, why do it again when you decide to switch?

Here's a few things to keep in mind. In stock form, the Gen III hemi is light years ahead of any factory, LA-based engine in terms of power output and efficiency. The 345 c.i. engine in my truck ('17 Ram 1500) makes over 400hp with exhaust manifolds. It tows a loaded trailer like it's not even there so there's more than enough torque on tap to get an A body moving quickly.

Honestly, what factory small block even came close to that kind of performance? The answer is none of them. Realize that stock Gen III heads flow almost 300cfm on the intake side while most stock LA heads are lucky to flow 220cfm. You can argue the minutiae between particular examples of each all you want but generally speaking, the performance potential between the two platforms in relatively stock/budget form is not even close, the hemi wins every time.

It's hard to argue with lighter, higher-flowing aluminum heads, bulletproof bottom end, better sealing surfaces and more efficient heat management... plus parts availability is much more plentiful since at least for now you can walk into any parts store and get what you need without having to mail order them.

I get it, you have an idea and want to try it. It's your deal, do what makes you happy but again if it were me, I'd go Hemi, it will be a better choice in the long run especially if you're planning to do it at some point anyway.
 
rmchrgr said:
Why go this route?? Perhaps I'm not fully understanding your plan but allow me to provide a counterpoint to what I think you're suggesting. You're basically saying in your statement above that you're ultimately going to go Gen III so why waste time and money on a middle step? Yes, the hemi is going to require different exhaust, fuel system, wiring, accessories, etc. which adds up quick. But if you have to obtain all those parts now for the small block, why do it again when you decide to switch?

Here's a few things to keep in mind. In stock form, the Gen III hemi is light years ahead of any factory, LA-based engine in terms of power output and efficiency. The 345 c.i. engine in my truck ('17 Ram 1500) makes over 400hp with exhaust manifolds. It tows a loaded trailer like it's not even there so there's more than enough torque on tap to get an A body moving quickly.

Honestly, what factory small block even came close to that kind of performance? The answer is none of them. Realize that stock Gen III heads flow almost 300cfm on the intake side while most stock LA heads are lucky to flow 220cfm. You can argue the minutiae between particular examples of each all you want but generally speaking, the performance potential between the two platforms in relatively stock/budget form is not even close, the hemi wins every time.

It's hard to argue with lighter, higher-flowing aluminum heads, bulletproof bottom end, better sealing surfaces and more efficient heat management... plus parts availability is much more plentiful since at least for now you can walk into any parts store and get what you need without having to mail order them.

I get it, you have an idea and want to try it. It's your deal, do what makes you happy but again if it were me, I'd go Hemi, it will be a better choice in the long run especially if you're planning to do it at some point anyway.
Click to expand...
You're 100% on point. Here's the thing. The last time this car was driving it was a 410 stroker and a straightline car. I had no idea at that and still don't on how this car "handles" the Gen3 does everything in one full swoop, but in all honestly it's too much more my driving ability currently.

It was more of my EGO that wanted more power and to go faster. The 410 was in the car for all of 750 miles MAYBE before I sold it. The reason I want to go this route is because I am not comfortable driving the car, nor do I recall what it feels like. I have only driven small sports cars that made maybe 300-400whp. These cars are going to be a different experience from driving a full size vehicle. The weight and power will be similar, but the width and length of the car will have adverse effects on the driving and handling.

This is more of a hey, I still want to do the Gen3 but I am willing to admit that going directly to the Gen3 may be too much for me until I can remember what it feels like to drive the car with stock like power.


I have almost all the parts to complete the hemi swap, but the last memory I have driving this car was it fishtailing on me at a low speed when all I had was a lead foot.


I would like to get to know the car before I add more power to it, so the plan has changed to getting to know what she feels like again before I just throw a whole bunch of power at it.


Plus the other thing is, steel blocks and carb engines are where I started. All I did when I was younger was rush to make more power because I was keyboard racing people. I never really got to enjoy anything other than what my EGO wanted with making more power. I want to start from the bottom again and enjoy remembering how to do this all. I haven't driven a MOPAR or worked on a MOPAR engine for almost 10 years. It's been all air cooled racing stuff and it's a different animal, so I need a refresher and I am okay with restarting to feel comfortable


I hope this helps clear things up some
 
You don't want a 318 with 273 heads and an RV cam in something that goes to a track. You'll be getting your *** handed to you by stock NB2 Miatas... on the straights.

Stock bottom end 360 Magnum will handle about 500 HP all day long but to make that kind of power you'll need aftermarket heads for sure in addition to cam and intake, obviously.

The '70 Duster in my avatar has been my long-term work-in-progress road racing car. The current engine is a stock 5.9L Magnum short block (pistons, crank, rods) with ported Edelbrock RPM heads, RPM intake, custom-grind Racer Brown hydraulic roller cam and shorty headers. Around 9:1 compression. It recently did a 1/4-mile pass in 12.65 seconds at 108 mph which translates to around 450 HP at the crank. It would probably pick up 20-40 HP with a set of long tube headers which I own (Doug's D-453) but have yet to install. It also needs a more race-oriented carb, the 750 cfm Street Demon works OK but I either need to go to a carb with bigger bowls or upgrade the fuel system for more flow as it leans out wide-open at higher RPM.

BTW I shift at only about 5500 RPM. SBMs make a lot of torque for the displacement (especially 360s) so they don't need much RPM to hit 400-500 HP. Remember power is just torque times RPM divided by some constant (5252 for HP and lb-ft).

I agree with @rmchrgr though, just put the G3 Hemi in and keep it stock for now. It'll make a bit over 400 HP which is plenty manageable if you do the proper chassis, suspension and brake mods to handle it. I've actually never driven a sports car and my Duster is the only thing I've driven on a road course or autocross. The key is simply not to give it full throttle all the time, start slow and work your way up to find the limits of the car. I've ridden with friends in their Miatas and other small underpowered stuff and they use the gas pedal like an on-off switch and shift like they're trying to rip the transmission out of the car.
 
MopaR&D said:
You don't want a 318 with 273 heads and an RV cam in something that goes to a track. You'll be getting your *** handed to you by stock NB2 Miatas... on the straights.

Stock bottom end 360 Magnum will handle about 500 HP all day long but to make that kind of power you'll need aftermarket heads for sure in addition to cam and intake, obviously.

The '70 Duster in my avatar has been my long-term work-in-progress road racing car. The current engine is a stock 5.9L Magnum short block (pistons, crank, rods) with ported Edelbrock RPM heads, RPM intake, custom-grind Racer Brown hydraulic roller cam and shorty headers. Around 9:1 compression. It recently did a 1/4-mile pass in 12.65 seconds at 108 mph which translates to around 450 HP at the crank. It would probably pick up 20-40 HP with a set of long tube headers which I own (Doug's D-453) but have yet to install. It also needs a more race-oriented carb, the 750 cfm Street Demon works OK but I either need to go to a carb with bigger bowls or upgrade the fuel system for more flow as it leans out wide-open at higher RPM.

BTW I shift at only about 5500 RPM. SBMs make a lot of torque for the displacement (especially 360s) so they don't need much RPM to hit 400-500 HP. Remember power is just torque times RPM divided by some constant (5252 for HP and lb-ft).

I agree with @rmchrgr though, just put the G3 Hemi in and keep it stock for now. It'll make a bit over 400 HP which is plenty manageable if you do the proper chassis, suspension and brake mods to handle it. I've actually never driven a sports car and my Duster is the only thing I've driven on a road course or autocross. The key is simply not to give it full throttle all the time, start slow and work your way up to find the limits of the car. I've ridden with friends in their Miatas and other small underpowered stuff and they use the gas pedal like an on-off switch and shift like they're trying to rip the transmission out of the car.
Click to expand...
The Gen3 I have isn't stock. IT's a 6.4 with cam, intake work and more, so close to 5-600 whp. And Again, I am not comfortable with driving that much power in a light car "yet". I have driven a GT2 RS which has like 600-700whp, but again this is a computer assisted car, with electronic everything.

The duster is a manual steering, manual brake car.

I appreciate the vote of the Gen3, but it's a little ahead of where my driving capabilites are, especially without the modern safety features like ABS, traction control, power assisted/vacuum brakes etc
 
SRT_DSTRHOLC said:
The Gen3 I have isn't stock. IT's a 6.4 with cam, intake work and more, so close to 5-600 whp. And Again, I am not comfortable with driving that much power in a light car "yet". I have driven a GT2 RS which has like 600-700whp, but again this is a computer assisted car, with electronic everything.

The duster is a manual steering, manual brake car.

I appreciate the vote of the Gen3, but it's a little ahead of where my driving capabilites are, especially without the modern safety features like ABS, traction control, power assisted/vacuum brakes etc
Click to expand...

Gotcha, I didn't know the Hemi was built up at all (and a 6.4L to boot). Then just find a 5.9L Magnum in good shape and do heads/cam/intake, easy 400 HP. Stock they make around 300 HP.
 
MopaR&D said:
Gotcha, I didn't know the Hemi was built up at all (and a 6.4L to boot). Then just find a 5.9L Magnum in good shape and do heads/cam/intake, easy 400 HP. Stock they make around 300 HP.
Click to expand...
Yeah, I didn't provide much information at the start, I was just hoping to keep the the topic on the SB, but that's okay.

That's what I was thinking, but with the longer stroke of the 5.9, I know that it may not be the best for higher RPMS.

I do know that with more displacement we don't need to rev as high to make power, but I was hoping to do a classic build off what they used to do in Trans AM and get a 273 or 318 to make that 300-400whp but up higher.

But if it's going to be more hassle to get one of these engines to make power up top then I might have to accept the lower power band for now and then move the power band up as I mod the engine.
 
SRT_DSTRHOLC said:
Yeah, I didn't provide much information at the start, I was just hoping to keep the the topic on the SB, but that's okay.

That's what I was thinking, but with the longer stroke of the 5.9, I know that it may not be the best for higher RPMS.

I do know that with more displacement we don't need to rev as high to make power, but I was hoping to do a classic build off what they used to do in Trans AM and get a 273 or 318 to make that 300-400whp but up higher.

But if it's going to be more hassle to get one of these engines to make power up top then I might have to accept the lower power band for now and then move the power band up as I mod the engine.
Click to expand...

In that case you can get a 5.2L Magnum and do the same mods, it'll make basically the same power but higher in the rev range. I do know the Magnum valvetrain (and hydraulic roller in general) is limited to about 6400 RPM. There were a lot more 5.2s than 5.9s made and the demand is much lower for them so it would be cheaper and easier to find one.
 
MopaR&D said:
In that case you can get a 5.2L Magnum and do the same mods, it'll make basically the same power but higher in the rev range. I do know the Magnum valvetrain (and hydraulic roller in general) is limited to about 6400 RPM. There were a lot more 5.2s than 5.9s made and the demand is much lower for them so it would be cheaper and easier to find one.
Click to expand...

Thank You, this is what I was thinking and with the magnum style setup, I can use some cheby things like rockers.

This is my idea of either the LA or Magnum. I know that I can always have LA intakes drilled for magnum heads too. But the other benefit of the magnum is the roller cam and oil selection as well and not having to worry about break in as much
 
SRT_DSTRHOLC said:
You're 100% on point. Here's the thing. The last time this car was driving it was a 410 stroker and a straightline car. I had no idea at that and still don't on how this car "handles" the Gen3 does everything in one full swoop, but in all honestly it's too much more my driving ability currently.

It was more of my EGO that wanted more power and to go faster. The 410 was in the car for all of 750 miles MAYBE before I sold it. The reason I want to go this route is because I am not comfortable driving the car, nor do I recall what it feels like. I have only driven small sports cars that made maybe 300-400whp. These cars are going to be a different experience from driving a full size vehicle. The weight and power will be similar, but the width and length of the car will have adverse effects on the driving and handling.

This is more of a hey, I still want to do the Gen3 but I am willing to admit that going directly to the Gen3 may be too much for me until I can remember what it feels like to drive the car with stock like power.


I have almost all the parts to complete the hemi swap, but the last memory I have driving this car was it fishtailing on me at a low speed when all I had was a lead foot.


I would like to get to know the car before I add more power to it, so the plan has changed to getting to know what she feels like again before I just throw a whole bunch of power at it.


Plus the other thing is, steel blocks and carb engines are where I started. All I did when I was younger was rush to make more power because I was keyboard racing people. I never really got to enjoy anything other than what my EGO wanted with making more power. I want to start from the bottom again and enjoy remembering how to do this all. I haven't driven a MOPAR or worked on a MOPAR engine for almost 10 years. It's been all air cooled racing stuff and it's a different animal, so I need a refresher and I am okay with restarting to feel comfortable


I hope this helps clear things up some
Click to expand...
I think you should be commended for admitting that, not everyone would. That said, going through this middle step still does not seem like a great approach because any time you add more power, you will be going through the same relearning process. Give yourself the best opportunity to succeed and you will. You don't have to make the Gen III an absolute killer at first since in stock form it's already pretty good. The idea here is kinda like learning to play an instrument. It's always better to spend the coin on a decent piece because the cheap ones suck and make it hard to learn.

I'm in a similar boat actually. A couple years back I built a small block stroker that made 500 hp. Not bad, not earth shattering either. I broke it in on a dyno and made some pulls to see what it could do - 500hp was it. Even though it ran and sounded great and made decent power for what it was, I thought it should have made more and felt really disappointed afterwards. When I think back, I made some poor parts choices which I eventually realized was why it came a little up short. I don't think I had unrealistic expectations for it going in either but I was still feeling like I failed because it didn't hit the number I had in my head. Would it have been awesome anyway? Probably.

I had drag raced the car ('71 Duster) before with a different engine (it came with W2 headed 340) and it was a solid low 12 second car. The 340 was old and tired though and came out when I found a broken piston ring in #5. When I built the stroker engine I wanted to get the car in the low 11s and possibly crack the 10s if/when everything was optimized. pretty sure 500hp would have done that no problem but due to life circumstances, I never even drove it with the stroker combo and it ended up sitting for several years.

This last summer I finally got it on a stand and tore it apart hoping to prove it to myself I could 'make it better'. I spent a bunch of money on shiny new stuff and built it the way I probably should have the first time. So yeah, I spent a second significant chunk of money on a perfectly good engine that I never even drove. Funny thing is I might have a monster on my hands now. With the new combination it could very well go 10.30s.

Am I a little nervous about that? Yeah, definitely. Will I figure it out? Yeah, I'm going to have to. Making the car safe was a top priority to help me focus on driving instead of worrying about potential failures. Being unsure or uncertain is not an option, I have too much time, effort and money invested in the car and engine now not to follow through with it.

Hope that was useful.
 
SRT_DSTRHOLC said:
I do know that with more displacement we don't need to rev as high to make power, but I was hoping to do a classic build off what they used to do in Trans AM and get a 273 or 318 to make that 300-400whp but up higher.

But if it's going to be more hassle to get one of these engines to make power up top then I might have to accept the lower power band for now and then move the power band up as I mod the engine.
Click to expand...

it's not so much about the hassle, it's about the money to make that kind of power (from that starting point) and do so reliably.

if you're talking budget and stages of upgrades i'd say 5.9 from the yard is probably the easy and dirty way to make it happen. or start with a 360, or maybe that 340 block. those will give you the broadest selection of aftermarket go fast goodies both new and used.

is the rest of the car sorted? like, chassis wise? because that's a huge financial consideration as well.
 
rmchrgr said:
I think you should be commended for admitting that, not everyone would. That said, going through this middle step still does not seem like a great approach because any time you add more power, you will be going through the same relearning process. Give yourself the best opportunity to succeed and you will. You don't have to make the Gen III an absolute killer at first since in stock form it's already pretty good. The idea here is kinda like learning to play an instrument. It's always better to spend the coin on a decent piece because the cheap ones suck and make it hard to learn.

I'm in a similar boat actually. A couple years back I built a small block stroker that made 500 hp. Not bad, not earth shattering either. I broke it in on a dyno and made some pulls to see what it could do - 500hp was it. Even though it ran and sounded great and made decent power for what it was, I thought it should have made more and felt really disappointed afterwards. When I think back, I made some poor parts choices which I eventually realized was why it came a little up short. I don't think I had unrealistic expectations for it going in either but I was still feeling like I failed because it didn't hit the number I had in my head. Would it have been awesome anyway? Probably.

I had drag raced the car ('71 Duster) before with a different engine (it came with W2 headed 340) and it was a solid low 12 second car. The 340 was old and tired though and came out when I found a broken piston ring in #5. When I built the stroker engine I wanted to get the car in the low 11s and possibly crack the 10s if/when everything was optimized. pretty sure 500hp would have done that no problem but due to life circumstances, I never even drove it with the stroker combo and it ended up sitting for several years.

This last summer I finally got it on a stand and tore it apart hoping to prove it to myself I could 'make it better'. I spent a bunch of money on shiny new stuff and built it the way I probably should have the first time. So yeah, I spent a second significant chunk of money on a perfectly good engine that I never even drove. Funny thing is I might have a monster on my hands now. With the new combination it could very well go 10.30s.

Am I a little nervous about that? Yeah, definitely. Will I figure it out? Yeah, I'm going to have to. Making the car safe was a top priority to help me focus on driving instead of worrying about potential failures. Being unsure or uncertain is not an option, I have too much time, effort and money invested in the car and engine now not to follow through with it.

Hope that was useful.
Click to expand...
Thank You. I completely understand that it will be a whole process of relearning the car as I add more power, but here is the main thing. This car isn't anything like the first time it was built. Originally it was a SS Spring 275 tire with rake and stock front suspension. Now I have the Gerst front and rear suspension with Wilwood big brakes, 6 speed, full cage etc.

My idea is to enjoy the car and learn the car as if it was a v6 challenger and learn the in and outs before I buy me a hellcat with the ego of a 16 year old. The engine I build (LA or Magnum) won't be a full waist as I plan to build another car later on, but I just want to do this with the idea in mind that going from a new car that has all the assisted items back to a manual input car is not going to be a quick transition and adding a rocket for an engine just doesn't seem like the best idea for a something that is an unknown until all the settings for the suspension, brake proportioning etc get figured out.

I want the driver to be ahead of the car. I know how to drive a little more than I did back then, but not with this car. So I would like to continue to mod the driver before the car gets to it's final point and if that means spending a couple 1-3k to enjoy the process, it doesn't seem like that can be anything but a benefit in the long run, especially if the motor and knowledge can be used down the road for the next build
 
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