I've been reading around and began realizing that alot of people have setups similar to mine but seem to be pulling much better hp and tq numbers. Seems as tho they are using every bit of hp the engine can make...so i figured i'd start a post and we could all contribute ways to get extra hp fairly cheaply....

1. windage tray
2. lifter galley tray
3. crank scrapper
4. vaccuum pump
5. 1.6 roller rockers
6. back cut valves
7. ? (not sure about this one, i was told i could forget about buying a crank scrapper if i ran the engine at the track with 2qts less oil...doesn't sound like a great idea...anybody know for sure?)
8. dual pcv valves (same idea as vaccuum pump)
9. synthetic fluids

(feel free to add some more of your own...i'd like to find out some of the less well known secrets)

 

if you want to get every last bit of preformance from an engine look at what the NHRA stock class racers have and do. some of the things you mentioned wouldn't be stock class legal, but you wouldn't be following all the rules.

 

Isn't a windage tray (#1 in your list) the same as a crank scraper (#3)? I have an old article from one of the car rags that shows a guy making a crank scraper out of some scrap sheetmetal... only trouble would be trying to find the damn article

 

No, not the same thing... a windage tray is sort of like an extra baffle that goes between the crank and the oil sump, to keep them from interacting, usually installed on studs that stand it off below the crank. A crank scraper is a piece of thin sheet metal usually installed on the bottom of the block between the pan and the block, cut in such a way that the crank can just barely fit through it as it spins; the idea is to strip any oil off the crank as it passes by and return it to the sump rather than flying around with teh crank as a mist. A scraper isn't real effective, since it has to be cut to the largest dimension of whatever parts of the crank rotate through a given point, and doesn't necessarily fit real tight to the crank at the points (rod bearings) where the oil is coming from; but like lots of other things, every little bit makes a difference, and the increased HP from reduced drag is considered by many builders to more than offset the increased car weight.

A vacuum pump gives less improvement in HP than it costs in weight, unless you're running in a minimum-weight class, and have to ballast the car anyway.

Here's a few ideas, more to improve speed generally, not just engine HP.

• Increase tire pressure in the front tires
• straightest possible drive line alignment, while in the "loaded" state
• Electric fan rather than clutch or "flex" fan
• Wheel alignment, wheel bearings, & other running gear correct, again in "loaded" position as it will be under acceleration, rather than the usual steady-state attitude
• Cold air induction
• K&N Stub Stack if your breather is tall enough (>3" from air horn to lid)
• Thin oil
• NOT a high-volume oil pump
• Light piston pins
• Lightweight fuel pump push rod
• Properly located exhaust crossover in dual-exhaust setups (location is critical)
• LOSE WEIGHT!!!! If it doesn't push, or steer, or stop the car, or you don't sit on it, consider leaving it behind at the starting line. My favorite is just general junk in the car; loose bolts & change in the glove box, extra stuff of various sorts in the trunk, etc. Audio equipment is another one: that stuff really adds up in weight, it's not uncommon to see over 100 lbs of it in a car these days.

PCV valves have essentially zero effect at WOT, since there's no vacuum. However, headers with AIR fittings, and the check valves, but hook the input side of the check valves to the crankcase, works.

 

why do you say no High volume oil pump?

 

I believe that it's because HV oil pumps will sometimes flow more oil than a block can drain back into the pan. This creates problems when you've got pressure under the valve covers, and will also waste horsepower turning the bigger oil pump.

 

The volume of oil required by an engine is generally directly proportional to RPM (minus some minimal losses and inefficiencies). A standard pump will deliver more than enough oil volume to maintain correct pressure. A high volume pump will only create additional load as it tries to move more oil than the engine can take, fighting against the pressure relief spring to simply dump that extra oil back to the pick side of the pump. This extra load is not only a waste of power generated by the engine, but creates oil heating and enough additional load on the pump shaft, distributor shaft, and camshaft distributor gear that failures can result. There isn't a lot worse than shutting off oil flow at 7,500 RPM.

 

Because the actual oil flow requirement of the engine is determined elsewhere; and if you use a high volume pump where it's not needed (like in virtually any motor with a stock oiling system), all it does is waste power moving oil around inside itself and the pan. It takes more power to pump more oil to the desired pressure.

 

I have heard of racers using a 7 qt oil pan with 5 quarts of oil. This still gives you plenty of oil, but keeps the crank farther away from the bottom of the oil pan. thus not picking up any unwanted oil.

 

Like he said above remove as much weight as possible. I've seen good results running a car 1 quart low on oil--more helpfull if you don't have a crank scraper. Don't overlook the obvious--tune it up. Get the timing set at it's best power producing level. Air/fuel mix at it's best power producing level. etc....

 

dammit i wish i had known that when i rebuilt my engine, i wouldnt have gotten a hv oil pump..

 

Where?

 

The place is where the pressure inside the system on each side is the highest. You find that with temperature. Paint a stripe of temp-sensitive paint down each side, make a pass or a hot lap or 2, it will show you where it's hottest; that's where you put the X or the H or whatever your mechanical design allows.

 

So many good points all ready.

#1. Reduce weight. A 300 HP 2800 pound car is quicker than a 300 HP 3800 pound car.

As mentioned above, look to see what Stock Eliminators cars have done. There are a lot of tricks that can be used.

Although there are a lot of good suggestions some may not apply. Is this a track only car or street/strip? There are a lot of things that can be done to a track only car that you wouldn't want to do to a street car that's expected to last 100,000 miles.

Reducing the weight of any rotating mass. This means a lightweight crankshaft, aluminum con rods and lightweight pistons. Moving to the drivetrain, an automatic transmission can get aluminum drums instead of the heavy cast iron ones. Aluminum driveshaft will help on the street but isn't very strong for the track. Carbon Fiber is better. Differential weight loss depends on the diff being used. Typical racer 9" can use an aluminum center section. Having gun drilled axles also reduces weight.

Reducing friction. Many good suggestions already. I only run 6 quarts of oil in my 7 quart pan. I have a windage tray and rear sump baffle but don't use a crank scraper. Using synthetic oils everywhere will reduce friction. There are many modifications that can be done within an automatic transmission that can reduce friction.

 

yea, i know weight plays a big factor, i was really only looking for driveline improvements, but i'm learning stuff anyways. Steven, how can you reduce friction in the trans? I don't think i've ever heard that being discussed, is it appliable to 700r4's or just 350's and 400's?

I also remember you saying a while back something about having the crank done so that the firing order changes and #5 and #7 change places and it makes more horsepower, how's it work, how's it done, and how much does it help?

i've been looking through some stock class forums, thats what inspired this post, but they seems to be arguing about trivial things, like whether or not heads should be allowed to be ported and still be allowed in stock eliminator...i'll keep looking though, i'm sure the information is there if i take the time to find it.

out of curiosity, does anybody know how much hp and electric fan and/or an electric fuel pump free up?

 

You can lower the trans internal friction by not stacking the clutches so tight, since whichever clutches aren't engaged at any given moment, are spinning inside the drum and wasting power as the frictions rub the steels. But, to make it shift the best possible, you want them as tight as you can get them, so it's a compromise.

You can't exchange #5 and #7 on the crank, look at a crank and you'll see why. You can change the firing order by changing the cam, but #5 and #7 aren't the ones you swap. Look at the LS1 firing order. You do that to try to even out the exhaust and intake flow such that 2 adjacent cylinders no longer fire next to each other.

 

What he just said. You can even eliminate some of the frictions and take up the extra space with a steel. Those frictions spinning in the tranny oil will have viscous drag.

Another thing in the tranny to reduce friction that I know of only deals with TH400's. A pre '67 style pump has thinner gears and takes less HP to turn. Another modification is to use a lighter spring in the pump pressure regulator to reduce the oil pressure. The same idea as the engine oil pump. Low pressure doesn't take as much HP to make.

The TH350 pump is the same way but they went to wider gears in 1978.

Other modifications include using straight cut planetary pinion gears. They won't force themselves back against a thrust washer and create more drag.

 

Electric fuel pump, maybe 1-2
Electric fan, maybe 5
Electric water pump, maybe 5

All the electrical devices now put a higher load on the alternator which only uses about 4-5 hp.

 

One of the car mags did a fan comparo on a 450ish hp small block Chev. The stock type, clutch fan drew 45 hp from the engine! I assume that this is with the clutch fully engaged. I would guess that "disengaged" the fan would probably draw about 5-7 hp, but that's a guess.

The electric fan they used drew 1 hp through the altornator compared to no fan. That's alot of free hp. and the only time the electric should be on is when your sitting in traffic (or the staging lanes).

 

Think I'm in luck then with mine I've got an early TH400, or have been told I do.

 

Early TH400's are not all that great. There are good parts in them but the later ones had better changes. Since everything can interchange you can mix and match the parts to make a very strong TH400.

I think the best year to find that has many of the good parts is 1970.