hp estrimate again.

[67 chevelle]

the article 67 c30 linked to is an excellent read

[c20pickup]

Originally Posted by 67_C-30

As min said, the casting numbers are the best way to ID them, but most have markings on the front of the head that can give you idea of what you have.

thanks for the reply, I will get the numbers tomorrow but it looks like (from the picture) I have 462624's or 333882's I will check for sure tomorrow tho

[c20pickup]

Originally Posted by 67_C-30

BTW, I don't mean to sound harsh, I'm just giving you the reasoning behind the estimate.

no offense taken! id rather have someone tell me the way it is then blow smoke up my, well you know what I mean. do you think I was taken for a ride by the machine shop and lied to when I was told 10:1 and 350hp? really disapointed

[Critter]

The biggest thing that guys overlook in a conversation/thread like this is tuning. You can have the best parts on earth but if an engine isn't tuned you might only be making 75% of what it could. Air/fuel ratio, timing along with timing advance curve, jets, etc all play a vital roll in getting everything out of your engine. For instance I had a very nice 1970 Mach 1 mustang come by a few weeks ago. The car ran smooth down the road but was gutless. I spent a couple hours adjusting the carburetor and timing and it went from 180 rear wheel hp to 265 hp. The motor was brand new, carb was brand new, everything freshly assembled by a custom builder but they had just bolted the parts together and called it good.

[67_C-30]

Originally Posted by c20pickup

no offense taken! id rather have someone tell me the way it is then blow smoke up my, well you know what I mean. do you think I was taken for a ride by the machine shop and lied to when I was told 10:1 and 350hp? really disapointed

Unfortunately, yes I do. There's just not enough there to make 350 HP. Them telling you that they were 10:1 is the biggest problem. They are 10:1 pistons with 64cc Vortecs or double hump/fuelie heads, but not with 882's or 624's. Those heads have 76cc chambers, and make a little less than 9:1 with flattops. Its harder to make 350 HP with stock smog heads and still be anyways mild/streetable. Your cam, intake, carb, headers, and bottom end (if properly assembled) is capable of the 350 HP mark, but your heads are your bottle neck right now.

[67_C-30]

Originally Posted by Critter

The biggest thing that guys overlook in a conversation/thread like this is tuning. You can have the best parts on earth but if an engine isn't tuned you might only be making 75% of what it could. Air/fuel ratio, timing along with timing advance curve, jets, etc all play a vital roll in getting everything out of your engine. For instance I had a very nice 1970 Mach 1 mustang come by a few weeks ago. The car ran smooth down the road but was gutless. I spent a couple hours adjusting the carburetor and timing and it went from 180 rear wheel hp to 265 hp. The motor was brand new, carb was brand new, everything freshly assembled by a custom builder but they had just bolted the parts together and called it good.

Critter makes a great point, and the numbers are giving you are based in being tuned properly. There's a lot of engines out there with the carb and timing off that are making way less than the person could ever imagine. A lot of these engines are seemingly running OK, and the person has no clue how far off it really is. We've went to the track before helping some people tune their cars simply with some timing tape, timing light, a dist re-curve kit, and a Holley strip (jet) kit and get the car running more than a half a second faster by just getting the total timing dialed in and jetted properly.

[c20pickup]

Originally Posted by 67_C-30

Critter makes a great point, and the numbers are giving you are based in being tuned properly. There's a lot of engines out there with the carb and timing off that are making way less than the person could ever imagine. A lot of these engines are seemingly running OK, and the person has no clue how far off it really is. We've went to the track before helping some people tune their cars simply with some timing tape, timing light, a dist re-curve kit, and a Holley strip (jet) kit and get the car running more than a half a second faster by just getting the total timing dialed in and jetted properly.

thanks for your help man, it is some disheartening new, but hey its the truth. I appreciate it. I will get the casting number tonite just to be sure, but I wont be expecting a change. ill have to go in and talk to the machine shop and ask them whats up with the inaccuracy. I guess this gives me an excuse to buy some edelbrock aluminums or vortecs

[c20pickup]

Well guys just went and looked, unfortuneately i have the 624 casting heads.... Not very happy right now

[Longhorn 70]

There are BIG valve 624s that work well on the street. They are said to be "prone to cracking" but if you keep them cool they last. They are 76CCs but you get to run regular unleaded in them.

[c20pickup]

Originally Posted by Longhorn 70

There are BIG valve 624s that work well on the street. They are said to be "prone to cracking" but if you keep them cool they last. They are 76CCs but you get to run regular unleaded in them.

running a 93 octane pump gas doesnt concern me(93 octane i believe is safe for 9:1 and 10:1 correct?), this truck wont be as much of a daily driver as it will be a weekend driver, drive it to the show, take it to the strip kind of deal.
i think my decision will lie in what the machine shop has to say, but for now i think i will run the motor in its current setup until the truck is done and i have some money laying around. but shortly after, i will be looking into a set of new heads. i dont think i want to run used heads (experienced that with this motor, the heads were used and i foolishly spent a couple hundred bucks to have them fully rebuilt ) id spend a couple hundred extra to have a new set rather then fool around with buying a used set that i have no history on

this leads me to my next question for you guys (you all seem very knowledgable on this subject) what kind of heads should i buy? i plan on keeping my cam set up, same intake, maybe a different carb (i like the demon carbs) just need a head change. should i go aluminum, or stick with cast iron? i was looking at edelbrocks website on there alumiunum heads (edelbrock is a name i know and trust, that why i went there first) but they have several different series of heads and im not sure which one is best for my application, should i look into different brands? dart, trick flow, afr? you guys tell me, given my current setup what would be the best bang for the buck purchase? ultimately i would like to get 375hp out of my current setup (is that do able?) or even more maybe?

[c20pickup]

or should i bite the bullet and buy one of the topend packages and have an advertised 435hp/435ftlb small block... hmmmmm

[bbcmudtruck]

For starters, the topend packages are advertised with higher output than I've ever seen someone on the dyno end up with. Not saying that they are bad packages, just don't think your going to bolt on 400+hp and tq. For the cost of a topend package, you could do several things to make your motor come alive. I'm a big fan of the AFR heads. They are pricey, but you get exactly what you pay for. Go small on the heads, as they are very efficient and don't require huge runners to get big power. The Brodix Race Rites are another good option. A good intake, set of rockers and a cam to match your heads will yield a great little motor. Its easy to just pickup a pre packaged top end deal, however I'd spring for just a little bit more money (if that's an option) and go with a retro fit hydraulic cam and lifter setup to match your heads and intake. It may sound daunting if this is your first build, but if you just call the right shops, you'll have everything you need. Actually you can call one shop in particular that will set you up right the first time. Chris Straub. Google claysmith cams and that's your guy!

[Critter]

I will agree that the advertised dyno numbers for aftermarket packages aren't usually realistic to the average hot rodder. First off they are talking about crank hp numbers. they set up an engine with everything perfectly machined and balanced. After they put on the parts being sold they sit at the engine dyno for hours on end tweaking and tuning and trying different options until they squeeze out every last drop of power. Usually by that time the motor is timed in a way that it is no longer a real world drivable engine. Not to mention that average guy in his garage or even working with a machine shop will never tweak the engine anywhere close to that to get everything setup even close to the perfect conditions that were used for dyno graphs. Unfortunately 9 times out of 10 when I dyno a vehicle that has never been on the chassis dyno the owner is disappointed in his numbers. Either because he had advertised crank HP numbers in his head or the vehicle just flat out isn't tuned right.

[mmiddle]

^^^^ Whole heartedly agree with the last two posts! The manufactures are posting advertised perfect world numbers. Those kits will undoubtedly wake up your motor and you will like the new power addition, just don't believe your 300HP engine will instantly become a 450hp monster.

And I also agree that bigger is not always better. Intake ports size/ valve size/ cam is best kept conservative for a general use truck.

[c20pickup]

what are your guys opinions on the edlebrock aluminum heads? when the time comes i will be looking to spend 900-1100$ what would be the best bang for the buck head i could buy? would my current set up respond well to a head setup? (performer intake, 650 carb (will be upgraded), crane z-274) with a set of 64cc aluminum set of heads give me 400hp after some tuning? or should i start from scratch wit a new cam and intake and heads?

[c20pickup]

any other good heads for my 900-1100$ budget?

[mmiddle]

What do you want to do with the truck? General purpose truck use, Grandma's grocery-getter with a large trunk, or a Saturday night street fighter?

[67 chevelle]

Originally Posted by c20pickup

this leads me to my next question for you guys (you all seem very knowledgable on this subject) what kind of heads should i buy?

Vortec heads are hard to beat , for the price and performance , perfect for a 400 hp +or- small block

[67_C-30]

Here is a great shootout of budget SBC heads heads, and the baseline engine has the heads you have. We've built a couple of engines with the Patriot heads in the article, and they flat out work. They've seemed to hold up well, and are good quality for the price. The Edelbrocks work well also, and I'll some guys put a whole bunch of miles on them. Considering the price of the Patriot, Jegs, or Summit heads, I would not buy Vortecs either modified or having them modified to run a cam over .480 lift and having to buy a Vortec intake as well. They are good heads if you already have them or getthem dirt cheap, but aluminum heads very reasonable these days, and you can run higher CR without detonation than with iron heads.

http://www.carcraft.com/techarticles...head_shootout/

[67_C-30]

Originally Posted by Critter

I will agree that the advertised dyno numbers for aftermarket packages aren't usually realistic to the average hot rodder. First off they are talking about crank hp numbers. they set up an engine with everything perfectly machined and balanced. After they put on the parts being sold they sit at the engine dyno for hours on end tweaking and tuning and trying different options until they squeeze out every last drop of power. Usually by that time the motor is timed in a way that it is no longer a real world drivable engine. Not to mention that average guy in his garage or even working with a machine shop will never tweak the engine anywhere close to that to get everything setup even close to the perfect conditions that were used for dyno graphs. Unfortunately 9 times out of 10 when I dyno a vehicle that has never been on the chassis dyno the owner is disappointed in his numbers. Either because he had advertised crank HP numbers in his head or the vehicle just flat out isn't tuned right.

I agree with idea that the average guy can't just all bolt this together and end up with the advertised numbers, but if the package is properly tuned, they will yield times on the track very close to the numbers to advertised numbers should get. A friend of our's put the Edlebrock Performer RPM kit on a GM 350 crate engine his street/strip '72 Nova. After a few times at the track and tweaking it in, we got 12.30's @ 107 out the car, and it weighed 3240# with him in it. That's knocking on the door of the advertised numbers Edelbrock claims.

I will say that car was running 12.50's and 12.60's when he first put it together without track tuning, so that reinforces what you are saying about the average guy just putting this in his car/track calling it a 420 HP engine.

[Critter]

67_C-30, definitely. We are in agreeance. The point being that if you want to max out your horsepower you have to tune the engine, that can be on a chassis dyno or at the track. The track may even be a little better at achieving real world power but it is much, much more inconvenient. Engine dynos are great but they don't really get you all the way there. The engine needs to be in the car/truck to really optimize everything. However, I would never tell people they HAVE to have their engine tuned (dyno or track) for it to be a fun/well running vehicle. You can do a lot by ear, nose and seat of the pants as long as you know what un-burnt fuel smells like. If its just a cruiser or daily driver then you don't really have to mess with hard core track or dyno tuning. Good conversation here, by the way!

[67_C-30]

Originally Posted by Critter

67_C-30, definitely. We are in agreeance. The point being that if you want to max out your horsepower you have to tune the engine, that can be on a chassis dyno or at the track. The track may even be a little better at achieving real world power but it is much, much more inconvenient. Engine dynos are great but they don't really get you all the way there. The engine needs to be in the car/truck to really optimize everything. However, I would never tell people they HAVE to have their engine tuned (dyno or track) for it to be a fun/well running vehicle. You can do a lot by ear, nose and seat of the pants as long as you know what un-burnt fuel smells like. If its just a cruiser or daily driver then you don't really have to mess with hard core track or dyno tuning. Good conversation here, by the way!

I totally agree - great discussion! I'll also add that car/truck's suspension has to be working at the track to achieve the numbers, and that's where a dyno has an advantage IMO.

As far as not needing track or dyno tuning, that's the truth for the vast majority of people out there. Most people that have never stomped a true 400 HP car/truck on a set of tires that sticking have no clue of how strong that actually is. I've given guys rides in some of our street/strip cars that had big block Chevelles and Camaros back in the day that had no clue how fast an 11 or 12 second car really is.

My '82 Z28 ran a best of an 11.18 @ 121 on motor with a stout 383 stroker. A guy I know that was always talking about how fast a 425 HP 427 Vette he used to have was, and that "He wouldn't even fool with a small block". I took him for a ride my Camaro one day, and there's an adandoned cotton mill down the road from us that has nearly straight road that nearly a 1/4 mile long before it goes into a slight curve. There's never any traffic down there, so we called it our "proving grounds".-lol I ran ET Streets when I drove the car at the time, so I went down there, stopped and did pretty good little burnout enough to get the tires sticky. I rolled forward a little bit and pulled it up on the stall, and mashed it. It hunched just a little immediately, but hooked pretty hard for it being on the street. I turned her up to 6800 in first and second and let out at about 5000 in 3rd. My buddy was hanging on to the armrest and console and wasn't saying anything at first. I asked him if was OK, and was just nodding his head and laughing after a few seconds. I asked him how he felt about a small block after that. He just said "Yeah, I guess things have changed". He said "I've never felt a car pull like that, and I didn't think a N/A small block could run like that!". I told that my small block wasn't even radical and that were a whole lot of them out faster than mine.

To make a long story short, he had a rectangular port, solid lifter BBC, but it was in a car on street tires, with a stock converter. He had never felt a tuned car putting a lot of power to the ground. His idea of fast was way off because he'd never been in a truly fast car. The majority of people fall into this category.

[c20pickup]

Originally Posted by mmiddle

What do you want to do with the truck? General purpose truck use, Grandma's grocery-getter with a large trunk, or a Saturday night street fighter?

hmmm, out of the options listed id choose saturday street fighter, something i can take to the strip, drive aorund town without overheating problems, and even run it down the highway, but by no means a daily driver. im putting to much money into this truck to risk having it wrecked on the road. i want something that is fun and fast and throws your back in the seat when you hit the skinny pedal

[c20pickup]

Originally Posted by Critter

67_C-30, definitely. We are in agreeance. The point being that if you want to max out your horsepower you have to tune the engine, that can be on a chassis dyno or at the track. The track may even be a little better at achieving real world power but it is much, much more inconvenient. Engine dynos are great but they don't really get you all the way there. The engine needs to be in the car/truck to really optimize everything. However, I would never tell people they HAVE to have their engine tuned (dyno or track) for it to be a fun/well running vehicle. You can do a lot by ear, nose and seat of the pants as long as you know what un-burnt fuel smells like. If its just a cruiser or daily driver then you don't really have to mess with hard core track or dyno tuning. Good conversation here, by the way!

id be willing to tune and test it, heck im already putting this much effort into the truck, why not spend a couple days at the track or on the dyno. seems worth the extra hp to me

[c20pickup]

Originally Posted by 67_C-30

Here is a great shootout of budget SBC heads heads, and the baseline engine has the heads you have. We've built a couple of engines with the Patriot heads in the article, and they flat out work. They've seemed to hold up well, and are good quality for the price. The Edelbrocks work well also, and I'll some guys put a whole bunch of miles on them. Considering the price of the Patriot, Jegs, or Summit heads, I would not buy Vortecs either modified or having them modified to run a cam over .480 lift and having to buy a Vortec intake as well. They are good heads if you already have them or getthem dirt cheap, but aluminum heads very reasonable these days, and you can run higher CR without detonation than with iron heads.

http://www.carcraft.com/techarticles...head_shootout/

reading the car craft link now, they have a different intake, and 1.6 rockers, slightly larger cam, however the the horspower for the stock iron heads was 358, which kind of surprised me, now i can see where the 300-325hp estimatescame from. this link is what i needed! helped alot! im looking at either the patriots, because of the torque numbers and peak hp numbers or the jegs, but i like the 815$ price of the patriots! now what is involved with swapping to 1.6 ratio rockers? just bolt on and go? or machining required? or am i better off sticking with the stock ratio (1.5? correct me if im wrong) which is better/worse. i guess i could be looking at just under 400hp, 400tq with a set of patriots or jegs, is this an appropriate estimate with my current setup?