DJ Dep

Nope...I don't have a problem with power. Heck, I don't have an ENGINE yet But I have seen so many of these posts I thought it might be worth looking into.
The vast majority of these posts seem to come from smallblock owners who are disappointed on "dyno day". Big block guys post stuff like "what do I do with all this power"

Most of these posts about lack of power come from guys who have done mods to their engine. The main problem seems to be that they want gobs of power, but also want to run on pump gas. What really blows me away is the amount of money and mods the people make to their cars to get more "power". So lets get to the basics first. I am no expert by any stretch, so I welcome suggestions by those that know more.

My suggestions:
FIRST thing that should be looked at for better performance for your car is the rear end gear. The installation of a higher rear gear is probably the ONE most noticeable thing you can do to get more power to the rear wheels. It is also the one of the things that will cause you to use more gas. In some cases, LOTS more gas. So if you are a penny pincher who wants to get 45MPG, you will NOT be happy with a steep rear gear. If you don't give a hoot about gas prices and are more interested in smoking the rear tires, a gear CAN get the job done. Of course, if you have the cash, you can install a 5 or 6 speed trans or a 4 speed auto. That will improve the mileage for highway driving. Note also that a rear gear will mean you have to rebuild your engine sooner since it's turning at higher revs than a 3.08 gear all the time.
Nothings free in this world

Next is excess weight. Those that are interested in keeping the Vette as an investment can ignore this section. Go look at a Barret Jackson episode of overpriced cars
Weight is the enemy of speed. Less weight means you go faster. It's simple. The more weight you strip off, the faster you go. There are numerous posts about stuff people have removed from their Vettes.
I won't go into the gory details of stuff ashcanned

And finally....the engine. Geez...you would think with the THOUSANDS of performance parts available for the smallblock Chevy since it's inception, people would be able to make power with it very easily. But this does NOT seem to be the case on the C3 forum. I don't know if it's because guys are buying parts *****-nilly and bolting them on as their budget permits, or if there are just so many parts to pick from that
people are just mixing the right stuff with the wrong stuff. Looking back at what Chevy was able to do with factory parts for the Vette, I would think that staying as close as possible to factory spec parts would be a good way to go. Note that Chevrolet built some HOT engines right from the factory WITHOUT adding a bunch of fancy heads, roller this and alloy that. Examples are the 302 Z-28 engine, the 327/365HP and 350HP engines, and the 350/350HP and 370HP engines.
I know this will tilt some folk's worlds completely off balance, but you do NOT need a laundry list of aftermarket parts makers to produce impressive horsepower from the smallblock. Note that ALL the engiens listed above had 10-1 compression or higher. Compression = power. There's no way to get around that.

Now to mods....
I often sit with my jaw hanging open at what people do to cars they drive around to the grocery store and to take their kids to school with. Here's some examples of wasted money:

Headers. Good grief. First off most people are installing the WRONG type of headers on street cars. The equal length 4 into one headers are great FOR THE STRIP on a RACE ENGINE. For the street, they are NOT the hot setup at all. A better header is the Tri-Y header. It's a bit more difficult to find, but it's usually cheaper and does a much better job for street engines. BTW...headers corked up with mufflers and an exhaust system does NOT mean an instant boost of 25 HP no matter what Flowmaster and all those other folks may say. Headers work best WIDE OPEN. Every bend and baffle the exhaust has to encounter SLOWS the extraction of exhaust. And if you have tiny intake and exhaust valves, headers will NOT give you much boost in power. Best thing about headers for the street is the loss in weight over the cast iron stuff. Oh yeah...one other thing. LOUD PIPES DO NOT MEAN FAST CAR. Spending a zillion dollars on mufflers is a complete waste. Buy some cheap steelpacks and save some money and when you get to the strip uncork them and THEN you will have a nice sound AND power.

Roller rockers. Geez. Fine for a guy that has GOBS of RPM and is racing every weekend. For the street...a total waste. Yeah yeah...less friction.
LOL..at what...4500RPM? If you're lucky you are getting 2-3HP and at a whopping price of $300!!!! Ack!!! Plus aluminum roller rickers have a short life expectancy. Stick with roller tip or factory stamped rockers. There are tons of guys running in Super Stock with LOTS more horsepower and RPM than any forum engine will see running just fine with factory stamped rockers.

Manifolds. Wow. I wish I had invested in manifolds back in the early 70s. Never thought I would see this many to pick from
Again, unless you are running MAINLY at the strip, staying close to factory-designed manifolds would be the best bet. I ran a Z-28 aluminum manifold on a 1971 Nova with a 350 engine, 350 horse Vette cam, and a 750 Holley double pumper. Ran great and never bogged.
Only had 8.5-1 compression too. Closest copy of that manifold is the Holley 300-36 Street Dominator. Without the Street Dominator name cast into it they would be identical.

Cam...I already have a thread on cams so I won't rehash that. Unfortunately, Chevy doesn't have many of the old school cams available. But there ARE "Muscle Car" cams being made by cam manufacturers that duplicate the specs of the original cam.

Heads...I see where Summit has heads for $954 a pair that duplicate the performance heads that came on the late 60's smallblock. They are not aluminum, but so what. You can still get plenty of power from them and you don't have to worry about stripping out threads.

Okay...that's about it. Feel free to add to it or criticize. Remember...I let taunts and criticism roll off me like water

Remember....if you build it with the KISS principle, you really can't go wrong. That would be Keep It Simple Stoopid

Dep

Gordonm

Good post. I like your thinking and agree with pretty much all of it. I am running a simple LT1 short block. fairly agressive solid cam with roller tips, not roller rockers and a set of AFR heads. Probably the most $$$ of the engine. A LT1 intake and 750 DP carb. It gets the job done and I know there is more in it with fine tuning. I should be in the low to mid 12s with this. Not gobs of power but more than enough for the street.

page62

Dep...for once I gotta admit you make sense.

But you did make one mistake. Summit sells heads that have the classic "fuelie" specs for 650 bucks a pair. And they're even better than the originals because they have vortec-style combustion chambers and computer-designed runners -- very close to CNC

LFZ

this obsession with power is a good question.. People think they can buy the latest and greatest stuff, slap it on, and they got some horsepower..but rear wheel hp and torque is what counts, and it takes more than just bolt ons for a L48 or L82. Sure Summit heads and an XE cam would help..but how much?? I think the "why is my engine not putting out this much power" is coming from obvious expectations that result in dissapointment

Jughead

Nothing fancy here Professor Dep.

I finished my first bottom up rebuild and it took a while for all you guys telling me to match my parts and not pick them ***** nilly. It finally sunk into my thick old skull and I think it paid off.

oregonsharkman

Can't argue with most of your logic there Michael..

I think some of the problem is many people think that 350hp at the crank should be roasting their tires in 4th gear at 2000rpm.........In other words some of the expectations of horspower gain is unrealistic.........
I have a few friends who ask me for advice on horspower increase........my recomendations are often balked at because of lack of "stated" horsepower for the money.

"you mean spending $300 on a holley carb is only going to gain me 10hp?????"....."No!!! the guy at the auto parts store said it was good for 75 hp and a full second in the 1/4 mile!!!!" "I am sure that a K&N air filter is worth 30 hp" and so on....

I agree that weight is the most overlooked item in speed (and handling) I stripped off about 300 lbs on my 76.....even with a L48 it became pretty quick......

On a side note it cost me over $3000 in mods (on top of purchase price) to make my vette as fast as my stock $5000 5.0 GT mustang....however I sold my 5.0 to pay for my 383 AR Racing Stroker.....Now I have the power that I always wanted and it is much faster than my mustang ever was.

DJ Dep

HEY!!! CUT THIS BS OUT!!! I was expecting some controversy here!!!! Youse guys are gonna ruin my repututation

Dep

WhichVette?

There are 2 things that I see very important:
1-Matching your parts so they work well together
2-TUNING

Keeping those in mind, everything else will fall into place.

surfshark

I took the old '80 smog motor out of my car a year and a half ago ( I barbequed it when the water pump died) and have changed my mind a million times as to the drive train. I even priced a nine inch rear end and blower motor. I then opened my big mouth to my wife about moving up to a nicer home and couldn't get out of that one. A great investment, but now I think I'll just put in that '70 350 with a bit of cam and I'm sure I'll have a blast with the 3.73 gear and the built turbo 350/2300 stall. I plan to keep it simple and just see what it'll do. I just miss the heck out of driving the car and hope I won't feel left out for not buying a high dollar crate motor. Doesn't mean I don't want one though.

PROSOUTH

See Mikee, I told you that you make a lot better sense when you take your Meds...........

jim

Top 3 To Bigs

1. To big of a Carb
2. To big of a Cam
3. To big of Expectations

oregonsharkman

NO!!! you just finally convinced us that you are right...

Jughead

Convinced??? More like brain washed.

Maybe we're in a cult like the "moonies" and don't know it.

page62

OOPS! Forgot three good little words: TUNED BY LARS!!!

bobs77vet

its obvious to me what the problem is ...they had their own cam custom ground.....they should have picked up a comp cam off the shelf.......sorry couldn't resist

rihwoods

You said: "Note also that a rear gear will mean you have to rebuild your engine sooner since it's turning at higher revs than a 3.08 gear all the time."

I have 119,564 original miles on a stock 78 L-82 (4 speed) 3.70 rear. What is your prediction for rebuild ? Mine is another 40,000-50,000 + miles.

gkull

Don't waste money on small stuff. Just go right to the 415 - 454 small blocks with roller cams.

mandm1200

Some of the post in regards to engine disappointments is low end torque. There are many parts that will give better performance for a street driven car. There are just as many parts, if not more, for higher rpm engines. We all know that if torque is moved higher the hp numbers will be higher. Higer rpms may be great for racing, but low to mid range driven cars should be built with parts that refect it. Too many people want to say they have AXZ aluminum heads when something like cheap, $450 a pair Vortecs, will foot the bill. Combine those heads with something like the L-82 cam with 10-1 compression and torque should be adequate. Then there is the carb. Unless you have tried several carbs sizes, you don't know how it 'feels'. A 750 cfm on a 350 is good if you're turning 7000 rpms and want a great top end. A 650cfm on the same engine will 'feel' better when punching it at 2500rpms.
The bottom line is determinimg where you want to be with the engine. Choose parts that complement each other for the rpm range. I don't expect a good low rpm engine to outrun a high perfomance, high rpm engine in the 1/4 mile; nor do I expect the race engine to work great when putting around in high gear at 50mph.

VETDRMS

You just get that 302 done, you'll be singing that sad song in no time.

Desertdawg

Dep, you must be a freaking rocket scientist.

BTW, I do agree with you about the Tri-Y's..but thats all I'm going to agree with you on...

GrandSportC3

People always expect to bolt on stuff and get those huge gains.. That's not how it works.. There are lots of factors involved to make a combination really work.. Let's say you install radical heads and cam but still run a dual plane low rise intake... Everything on the engine has to be designed for the same RPM range etc... Basically, you have to get rid of the bottlenecks to make a combination work etc...
Once you get the desired power, that doesn't automatically mean good times at the track.. As Dep mentioned, gearing etc. Is just as, or even more important than just power...