Moparts
How much horsepower do you really need????
Posted By: 70Sbird
How much horsepower do you really need???? - 07/25/08 07:31 PM
Ok just a hypothetical question here, how much horsepower do you really need for a relatively quick street car without sacrificing drivability/reliability or breaking the bank?
I just trying to plan and budget for a project car I’m contemplating. It’s a 71 Demon. My thoughts are a new generation Hemi (5.7 or 6.1, kind of why I asking this question) and an overdrive automatic trans, with probably a 3.73 to a 3.91 rear gear. This car will be a cruiser with much more street than strip time. Drivability means more to me than outright performance. I’m thinking that about 400 hp would really be all that I would need without getting too exotic or expensive. Also for any A body guys out there that are running similar specs, any idea how fast would this combo be in the quarter?
Any thoughts???????
By the way I already know that
A: Too much HP is never enough
B: Speed costs money son, how fast do you want to go?
Posted By: nutso suave
Re: How much horsepower do you really need???? - 07/25/08 07:40 PM
more power! grunt! grunt!
Posted By: skep419
Re: How much horsepower do you really need???? - 07/25/08 08:20 PM
i would build a stought 408 stroker bottom end and just use the stock heads for now. put an air gap on it with a descent holley. Then when the 400hp feels slow theres a lot more to be made
thats what i wished i had done.
Posted By: JF_Moparts
Re: How much horsepower do you really need???? - 07/25/08 08:23 PM
My 340 was dyno'd at 370HP and 407 ft/lbs of torque, and that's more than enough for me. Especially with gas at $4.60.
Jim
Posted By: 70Sbird
Re: How much horsepower do you really need???? - 07/25/08 08:39 PM
I guess that I should add I'm almost completely settled on a new Hemi, with fuel injection, a/c, power steering and all of the "modern" convieniences.
I've just seen a growing amount of variability with offerings for this engine, from a junkyard 5.7L truck engine to an $18,000 6.1L beast from a nationally recognized engine builder.
Thanks for your input!
Scott
Posted By: RapidRobert
Re: How much horsepower do you really need???? - 07/25/08 09:44 PM
as much as you can afford or until it scares you whichever comes 1st.
Posted By: RodStRace
Re: How much horsepower do you really need???? - 07/25/08 09:53 PM
you didn't mention weight, suspension or tire size. If you figure around 3300, stock and the biggest tire is 27 tall, 8 wide, the 5.7 should spin them easily. with the deep rear gear and late trans, you should have gearing to pul smartly up to at least 90+. How much do you really need, and how are you planning on putting it down?
Posted By: rrunner
Re: How much horsepower do you really need???? - 07/25/08 11:41 PM
This must be a trick question, right?
Posted By: forphorty
Re: How much horsepower do you really need???? - 07/26/08 12:02 AM
Posted By: AlexP
Re: How much horsepower do you really need???? - 07/26/08 12:38 AM
A cam/headers 5.7 Hemi will do over 400 hp easily.
Pull a low mileage 5.7, sell the tranny, get a truck front dressing (accessories), get the TTI headers and the XV intake, put a cam and run that thing...really basic with LOADS of room to grow.
Go drive an LX car, and then imagine one with less drivetrain loss and 1000 lbs less weight. There are longblock cam and exhaust 5.7 cars knocking on high 12's @ 4000-4500 lbs...
We are putting a stock shortblock 6.1 into my friends 67 Charger with a carb based cam with worked 5.7 heads....it will fly, and we will detail the process to show how much power these motors will make on a budget.
https://board.moparts.org/ubbthreads/show...rue#Post4534456
Posted By: Clair_Davis
Re: How much horsepower do you really need???? - 07/26/08 01:51 AM
I think any A-body + New Hemi is going to be a dynamite combo. I'm driving a 3600# Valiant with a low-squeeze 340 that makes an honest, untuned 300hp and 340lb-ft at the crank. With a 4-speed and 3.23 gears, it's a treat to drive - can spin the tires with ease, and has plenty of grunt. It's not the fastest car on the street at all, but it should crack in to the 13's. Add 100hp/lbft from the new Hemi and you're looking at 12's with virtually no down sides - except for initial cost, and complexity of fabbing up an injection system if you go that route.
IMHO, grunt makes the world go round. The HP will follow the torque if the breathing is there.
Clair
Posted By: jbc426
Re: How much horsepower do you really need???? - 07/26/08 01:53 AM
Always build more than you need. Remember, that's why we have throttles on these motors.
Posted By: Anonymous
Re: How much horsepower do you really need???? - 07/26/08 02:18 AM
Depens on what you can live with regarding street manners in terms of idle and bucking at cruise speed. If you drive it regularly in heavy traffic you will want to take this into consideration.
Posted By: 451Mopar
Re: How much horsepower do you really need???? - 07/26/08 03:01 AM
400 HP sounds like a good number, should put most cars in the 12's. If you go quicker than 11.50's the NHRA requires you to have a roll bar and other safter equipment.
Posted By: 383man
Re: How much horsepower do you really need???? - 07/26/08 03:42 AM
It really depends on how fast of a street car you want ?? If you want to beat alot of these newer cars then you might want to shoot for 11's. I mean I saw a Mercedes at the track running 12.40's that I believe was the supercharged V8 deal. I figure my 63 makes about 500 hp at the flywheel to push it at 3700 lb's to mid 11's and it really is a very mild 440 by todays standards. But with an A-body the smallblock stroker is the ticket. Very easy to get 450 to 500 hp and that would put your A-body well into the 11's and still be very streetable as you can do it with 3.91's as that's what my son uses with the 400 in his Dart. Good luck , Ron
Posted By: DemonKyle
Re: How much horsepower do you really need???? - 07/26/08 04:43 AM
I make 350hp and 400 ft lbs. from my 360 in my 71 Demon. With 3.23s its good for high 12's at about 105. Let me know if you want the engine combo
Posted By: 70Sbird
Re: How much horsepower do you really need???? - 07/26/08 10:04 PM
WOW!
This is why I love MOPARTS.
Lots of options here and lots of good feedback Thanks to all
I've been doing some additional reading on the 6.1 crate motor on a few other threads here and that sounds like a really good deal If the electronics all work out.
While I'm at it what is all of you opinion on an OD automatic trans? plenty of options here as well from a beefed 727 and a Gear Vendors Overdrive, to a TCI 4 speed automatic to the Chrysler 5 speed auto that will require floor surgery in an A Body. any suggestions?
Posted By: DemonKyle
Re: How much horsepower do you really need???? - 07/26/08 10:25 PM
I would run an overdrive in the demon if i had the money and could get one. Would love to have 3.91s or 4.10s out back all day long
Posted By: 70Sbird
Re: How much horsepower do you really need???? - 07/26/08 10:28 PM
Thats exactly my thoughts as well.
steep gears to get it out of the hole and still cruise at 70 mph at around 2500 rpm!
I'm just not sure which is the best option. I have not been in the market for a trans in about 15 years and things have changed!
Posted By: mark7171
Re: How much horsepower do you really need???? - 07/26/08 11:48 PM
gear and stroke have a relationship too.
you could use a highway gear and let the advantage of the stroke pull you forward. it will work as well as a gear multiplier.
Posted By: reno340
Re: How much horsepower do you really need???? - 07/27/08 12:27 AM
Quote:
more power! grunt! grunt!
R-R-r
Posted By: DaytonaTurbo
Re: How much horsepower do you really need???? - 07/27/08 03:23 AM
I'm with Ron on this one. A lot of modern factory performance cars are running 12's these days. Granted not every Tom, Dick and Harry are driving one, but they are out there. And after you go through all that work, do you want to get owned by someone in a new all-stock car? No, so that's why I'd say shoot for 11's. Or at least build the combo so the potential for 11's is there down the road.
Posted By: ZIPPY
Re: How much horsepower do you really need???? - 07/27/08 02:56 PM
499.74 at the rear wheels is a bit much for me, but I'm getting used to it....still haven't run at the strip in that configuration, hopefully soon....
Posted By: AdamR
Re: How much horsepower do you really need???? - 07/27/08 03:55 PM
I would be happy with around 1500hp.
At the wheels.
Posted By: hemibeep
Re: How much horsepower do you really need???? - 07/27/08 10:59 PM
For my 71 runner, going for the 6.1. With head work and cam upgrade goal is 450 at the wheels. Yes using F.I., using 518, using the MSD iginition setup, using alterkation, TTI headers and exhaust. I will go with 4.10. 28" tall tires Should have the fire without the O.D. and cruise with the O.D.
I have seen 5.7 going for $600. How can you go wrong?
P.s. weight of motor about 560lbs.
Too many pluses to not try this combo.!
Posted By: hemibeep
Re: How much horsepower do you really need???? - 07/27/08 11:03 PM
Forgot to mention, I got the 518 with the three wire from a member here for $500. It has about 2k miles since rebuild, I am going to install a transgo shift kit, and let her eat.
Posted By: Alikazam
Re: How much horsepower do you really need???? - 07/27/08 11:36 PM
If it is really an option, I'd say to go with the 5 speed auto and do the necessary floor surgery. Can't beat taking ALL the modern conveniences and upgrades and stuffing them into a good old muscle car. Just my opinion
. And always remember, if its not fast enough, you can add nitrous and if it blows up you have an excuse to build it stronger to handle a supercharger or turbo
hehe.
Good luck.
Posted By: DennisH
Re: How much horsepower do you really need???? - 07/28/08 12:35 AM
Near 500 RW Dyno - not enough. Somebodies Avatar covers it-not enough till you're real scared...
Posted By: Dragula
Re: How much horsepower do you really need???? - 07/28/08 01:23 AM
If you have to ask....You cannot touch it!
Posted By: moparmojo
Re: How much horsepower do you really need???? - 07/28/08 01:58 AM
In all honesty, I think shooting for mid 12s is a great goal for the street. Many guys out there blab about how fast there cars are and there really aren't that many 12sec cars out there on the street. I'm basically talking about the cars that are not obvious race cars. So it is a nice surprise to see a fairly stock looking car run 12s. I also think 12s can be very streetable without much loss in drivability. I see more 12sec motors being built now than say 10 years ago, probably due to kits and cheaper parts. That was my goal. I wanted a fairly decent street motor for my convertible that would not give me headaches. It's a 500" 440source'd 440 with 513/533 voodoo cam and edelbrock heads. Somewhere around 9.2-9.3 comp ratio. Still need to pick a carb(if I don't go EFI) and probably new 3.55 gears. Hoping for 12s and probably have less in it than say a new 6.1 kit. Those new hemi's are nice but pricey. Plus a bit of a job to install, plus sourcing the right new parts.
Posted By: mnguy55
Re: How much horsepower do you really need???? - 07/28/08 02:18 AM
Quote:
It's a 500" 440source'd 440 with 513/533 voodoo cam and edelbrock heads. Somewhere around 9.2-9.3 comp ratio. Still need to pick a carb(if I don't go EFI) and probably new 3.55 gears. Hoping for 12s and probably have less in it than say a new 6.1 kit. Those new hemi's are nice but pricey. Plus a bit of a job to install, plus sourcing the right new parts.
I have thought about building another motor for my charger on and off for years because I cant bring myself to beat on my original one and I'd just like to try something different.
I am thinking something like what you described, a 500 stroker with eddelbrock heads. Here is a question. I know nothing about modified motors. I'd just like something that really goes but runs and sounds very stock. I'd definitely want to keep the original HP manifolds on it and the original intake manifold. I could live with a different carb as long as the original dual snorkel air cleaner fit. So, is it pointless to build a motor like this if you want to keep the manifolds on it, will they pretty much choke off any major power gains? The original motor in the car is a 70 440 4bbl. If you assume that the original motor had say 300 HP net how much could a mild cammed eddelbrock head 500 stroker make, assuming it had to run well on 91 octane?
Posted By: DemonKyle
Re: How much horsepower do you really need???? - 07/28/08 02:28 AM
Quote:
Quote:
It's a 500" 440source'd 440 with 513/533 voodoo cam and edelbrock heads. Somewhere around 9.2-9.3 comp ratio. Still need to pick a carb(if I don't go EFI) and probably new 3.55 gears. Hoping for 12s and probably have less in it than say a new 6.1 kit. Those new hemi's are nice but pricey. Plus a bit of a job to install, plus sourcing the right new parts.
I have thought about building another motor for my charger on and off for years because I cant bring myself to beat on my original one and I'd just like to try something different.
I am thinking something like what you described, a 500 stroker with eddelbrock heads. Here is a question. I know nothing about modified motors. I'd just like something that really goes but runs and sounds very stock. I'd definitely want to keep the original HP manifolds on it and the original intake manifold. I could live with a different carb as long as the original dual snorkel air cleaner fit. So, is it pointless to build a motor like this if you want to keep the manifolds on it, will they pretty much choke off any major power gains? The original motor in the car is a 70 440 4bbl. If you assume that the original motor had say 300 HP net how much could a mild cammed eddelbrock head 500 stroker make, assuming it had to run well on 91 octane?
Well the stock intake and exhaust manifolds would definitely choke the thing for air, especially in a stroker.
Posted By: Anonymous
Re: How much horsepower do you really need???? - 07/28/08 03:23 AM
Quote:
Quote:
It's a 500" 440source'd 440 with 513/533 voodoo cam and edelbrock heads. Somewhere around 9.2-9.3 comp ratio. Still need to pick a carb(if I don't go EFI) and probably new 3.55 gears. Hoping for 12s and probably have less in it than say a new 6.1 kit. Those new hemi's are nice but pricey. Plus a bit of a job to install, plus sourcing the right new parts.
I have thought about building another motor for my charger on and off for years because I cant bring myself to beat on my original one and I'd just like to try something different.
I am thinking something like what you described, a 500 stroker with eddelbrock heads. Here is a question. I know nothing about modified motors. I'd just like something that really goes but runs and sounds very stock. I'd definitely want to keep the original HP manifolds on it and the original intake manifold. I could live with a different carb as long as the original dual snorkel air cleaner fit. So, is it pointless to build a motor like this if you want to keep the manifolds on it, will they pretty much choke off any major power gains? The original motor in the car is a 70 440 4bbl. If you assume that the original motor had say 300 HP net how much could a mild cammed eddelbrock head 500 stroker make, assuming it had to run well on 91 octane?
I have a 1969 440 six pack Super Bee that has a new 523 stroker in it with factory exhaust manifolds. I built the car to somewhat F.A.S.T. standards as I like my cars to maintain a pretty much stock appearance. I have not yet had it to the track but it certainly "feels" like it will run high to mid 11s. The factory HP manifolds are not going to be a limiting factor for those kind of times.
Posted By: thecarfarmer
Re: How much horsepower do you really need???? - 07/28/08 04:56 AM
Q: How much horsepower do I really need????
A: Just a bit more than I can afford.
Seriously, as soon as I think one thing will be good enough, I start thinking greedier.
This has led to several mid-project changes/backtracks/upgrades. Such as stroker kit, roller cam, tunnel ram, blah blah blah. So maybe I'm not the right guy to ask (not sensible). Or maybe I am the right guy to ask, since I've already been down that road...
IMHO, I'd be pretty bummed if my musclecar with a 5.7 or 6.1 swap got waxed by some late model thing with a couple bolt-ons. I'm speaking for myself and nobody else; I'm not saying "I'm right - you're wrong" Just telling how I'd feel and how I view stuff.
If it were me, I'd make sure that whatever motor I put in the ol' A-body had some performance upgrades, so that the only late model cars that'd take it would have to either have power adders or some serious wallet thrown at them.
-bill
Posted By: 70Cuda383
Re: How much horsepower do you really need???? - 07/28/08 10:34 AM
talking about power, gears, and streetability...my stroker made 505 on the dyno...add on all the accesories, full exhaust, drivetrain, engine compartment...I'm probably at around 380-390 to the wheels.
with a 28.5" tire, 3.21 gears and the TKO-600 w/.64OD 5th gear, I cannot use 5th gear until I'm going 70 or better, otherwise it surges and lugs as I'm cruising. 70mph in my set up is only around 2100-2200 rpm, and I definitly have too much gear. when I wound it out through the top of 4th gear, my speedo was maxed out at over 120. it got there pretty quick, but I definitly don't need to be going that fast especially in 4th gear with all of 5th left.
Something else to consider with a "long stroke, high torque motor" is that with a high gear set up, and a manual shift car, you're going to have to slip the heck out of the clutch to get going. City driving can sometimes be painful because of how much I have to slip the clutch when pulling away from a stop.
I just ordered up a set of 4.56s to help me with that problem though, hopefully now I can roll around at 1100 rpm or so in 1st gear, and actually be at a safe, slow, parking lot speed!
Posted By: mnguy55
Re: How much horsepower do you really need???? - 07/28/08 11:00 AM
I have a 1969 440 six pack Super Bee that has a new 523 stroker in it with factory exhaust manifolds. I built the car to somewhat F.A.S.T. standards as I like my cars to maintain a pretty much stock appearance. I have not yet had it to the track but it certainly "feels" like it will run high to mid 11s. The factory HP manifolds are not going to be a limiting factor for those kind of times.
That sounds like what I am interested in. Pretty much stock apearing but significant power upgrade. What heads, intake, compression and carb are you running?
Posted By: JohnRR
Re: How much horsepower do you really need???? - 07/28/08 11:39 AM
Quote:
Quote:
Quote:
It's a 500" 440source'd 440 with 513/533 voodoo cam and edelbrock heads. Somewhere around 9.2-9.3 comp ratio. Still need to pick a carb(if I don't go EFI) and probably new 3.55 gears. Hoping for 12s and probably have less in it than say a new 6.1 kit. Those new hemi's are nice but pricey. Plus a bit of a job to install, plus sourcing the right new parts.
I have thought about building another motor for my charger on and off for years because I cant bring myself to beat on my original one and I'd just like to try something different.
I am thinking something like what you described, a 500 stroker with eddelbrock heads. Here is a question. I know nothing about modified motors. I'd just like something that really goes but runs and sounds very stock. I'd definitely want to keep the original HP manifolds on it and the original intake manifold. I could live with a different carb as long as the original dual snorkel air cleaner fit. So, is it pointless to build a motor like this if you want to keep the manifolds on it, will they pretty much choke off any major power gains? The original motor in the car is a 70 440 4bbl. If you assume that the original motor had say 300 HP net how much could a mild cammed eddelbrock head 500 stroker make, assuming it had to run well on 91 octane?
Well the stock intake and exhaust manifolds would definitely choke the thing for air, especially in a stroker.
Don't tell that to a few guys racing FAST ...
....
Posted By: JohnRR
Re: How much horsepower do you really need???? - 07/28/08 11:44 AM
Quote:
Quote:
I have a 1969 440 six pack Super Bee that has a new 523 stroker in it with factory exhaust manifolds. I built the car to somewhat F.A.S.T. standards as I like my cars to maintain a pretty much stock appearance. I have not yet had it to the track but it certainly "feels" like it will run high to mid 11s. The factory HP manifolds are not going to be a limiting factor for those kind of times.
That sounds like what I am interested in. Pretty much stock apearing but significant power upgrade. What heads, intake, compression and carb are you running?
To run on 91 octane you want to keep your compression in the 9.5 to 10.0 range with the alum heads .
Talk to fast68plymouth and/or DRAM about what you want and have them spec you a build and a CAM , you will not be disappointed .
fast68plymouth is the head porter/cam spec behind many of the fastest big block wedge headed mopars in FAST
Posted By: 71TA
Re: How much horsepower do you really need???? - 07/28/08 01:23 PM
Quote:
Depens on what you can live with regarding street manners in terms of idle and bucking at cruise speed. If you drive it regularly in heavy traffic you will want to take this into consideration.
I agree. I had a big mechanical and a single plane. NO FUN. MP528 and a dual plane on my 470" and it's a BUNCH more fun to drive (drove it to work today). Still probably near 600HP.
Could I use more? Yep. I've always wanted a blower car. The owner of an auto repair shop down the street from me drives a blown BB Chevlle with tubs and cage. NICE! I drove by one time while he was pulling in the driveway of his shop. When he lit em up it sceeeeered ME so bad I thought a jet was crashing near by - all the noise and vibration was INCREDIBLE.
Kinda like the how many licks to the center of a Toostie pop - the world may never know But I'd say MORE than 600HP.
I lit em up for about 10 feet last night and my wife was so sacred by the NOISE she said if I ever do that again she'll never ride in my car again I'm gonna see if she's serious.
Posted By: Anonymous
Re: How much horsepower do you really need???? - 07/28/08 05:36 PM
Quote:
I have a 1969 440 six pack Super Bee that has a new 523 stroker in it with factory exhaust manifolds. I built the car to somewhat F.A.S.T. standards as I like my cars to maintain a pretty much stock appearance. I have not yet had it to the track but it certainly "feels" like it will run high to mid 11s. The factory HP manifolds are not going to be a limiting factor for those kind of times.
That sounds like what I am interested in. Pretty much stock apearing but significant power upgrade. What heads, intake, compression and carb are you running?
The cam is a roller with 112 degree lobe seperation. Intake .022 valve lash hot .630 valve lift 284 duration Exhaust .024 .608 288, and after indexing the lift is 420/244 I and 405/252 E. The stock heads were ported and flowed. Of course it is balanced and blueprinted. For some reason the compression is not shown on the blueprint sheet, but it will run on punp premium. I have the stock original six pack intake and carbs with all of the Promax add ons. With all of the parts and labor I have around $11K in it including R&R.
Some of the winning F.A.S.T. guys are running up to 14:1 compression. We do not have F.A.S.T. racing here in the southwest and even if they did I would not go to those extremes. I want something that is still streetable for a 2 hour drive or more. My car is borderline as it has some around town surging due to the cam.
Posted By: DaytonaTurbo
Re: How much horsepower do you really need???? - 07/28/08 06:04 PM
Yeah but don't forget how much dough the FAST guys are dropping into having stock manifolds ported, or exrude honed or whatever they call it. The 6 pack intake is a good one for making HP, and you can put down some nice #'s with stock HP manifolds. With a stock 4bbl intake, not so much. Can still make some power, but it is way more restrictive than a 6-pack intake, which flow and performance wise keeps up with the modern street/strip intakes. With the right cam selection you can do a lot with the stock HP manifolds, but you would still gain more if changing to headers.
Posted By: Anonymous
Re: How much horsepower do you really need???? - 07/28/08 08:35 PM
My engine builder said that extrude honing the exhaust manifolds would probably not have any effect on my engines performance/speed/time. It may be something that the top F.A.S.T. guys are doing looking for any millisecond advantage, but certainly not worht the money that it cost for anyone else.
Posted By: 71TA
Re: How much horsepower do you really need???? - 07/28/08 09:58 PM
Quote:
My engine builder said that extrude honing the exhaust manifolds would probably not have any effect on my engines performance/speed/time. It may be something that the top F.A.S.T. guys are doing looking for any millisecond advantage, but certainly not worht the money that it cost for anyone else.
But it looks cool! I've seen those done.
When driving gto/from Carlisle I see the ExtrudeHuone company off the turnpike by Pittsburg I think.
Posted By: Anonymous
Re: How much horsepower do you really need???? - 07/28/08 10:49 PM
What is it that you think looks cool, it is all inside of the manifolds?