how to make a lil more h.p.

[justmejohn71]

all right im new to the site ive got a 71 chevelle street an strip car an i just wanna pop up the hp a little i have herd that a Electric Water Pump will give u a little more power is this true an if so is an Electric Water Pump street able?? thx

[jus_1982]

an electric water pump will indeed give you a little more hp because it takes a little stress off of your belt system, however im not too sure how street friendly this item is.

[Dave Severson]

Cheapest way to get more horsepower is to make the car lighter. How about some 'glass bumpers, hood, fenders.....or maybe some lexan side and back glass. Relocate the battery to the back. If it's weight you have to have, might as well put it where it will do some good.

[techinspector1]

An electric pump that will move enough water to cool the motor on the street will be very expensive and will be a trade-off anyway. It'll take just as much electrical energy (mechanical energy to drive the alternator to feed the pump) to run it as it took mechanical energy to drive the mechanical pump. There's no free lunch. Spend you money more wisely somewhere else on the car and follow Dave's sage advice about weight. 100 lbs equals 1/10th second at the drag strip.

[pro70z28]

Spray it

[MIT QUK]

Originally posted by techinspector1
Dave's sage advice about weight. 100 lbs equals 1/10th second at the drag strip.

I have always heard that. But I think it is relative.

If you take a 100lbs off your Peterbuilt and I take a 100lbs off my crotch rocket which will benefit more?

[Dave Severson]

I guess you might want to discuss that on a Peterbilt forum, or on a crotch rocket forum, here we are talking hot rods. I could get into the math on the thing and tell you what the gains would be, but I don't think it's necessary to say that the gains on the crotch rocket would be much more significant. I doubt it would be much of a gain on a Sherman tank, either.

[JSracing]

Another good bang for the buck is rear gear ratio change. I just changed mine from 4.88's to 4.11's What gear ratio do you have now?

[Dave Severson]

Why did you gear for more mph???? Depending on tire size, usually run 4.88's or 5.13's for the quarter, 6.50's on the 1/8th.

[JSracing]

Originally posted by Dave Severson
Why did you gear for more mph???? Depending on tire size, usually run 4.88's or 5.13's for the quarter, 6.50's on the 1/8th.

DAVE, I think it depends on the torque output and weight of the car. Back when I ran a small block I had 5.14 to 5.43's

I switched to 4.86's when I started running a big block and lately that is still too much gear.

Excessive RPM at the finish line, violent launches can equate to over gearing.

I know a guy who runs a sbc and has 6.00 gears... that's as tall as I've seen.

My car needs a "soft" hit at the launch.

[riverhorse59]

Originally posted by Dave Severson
Why did you gear for more mph???? Depending on tire size, usually run 4.88's or 5.13's for the quarter, 6.50's on the 1/8th.

Dave , I was thinking something simular to JS Racing. Maybe he was running out of cam and or motor. It's no use running 4.88s or 5.13s unless you have enough motor to pull all the way thru the quarter mile.
I have seen a lot of people run too much gear with a short rod 400 small block chevy. Then they wake up and find out the more gear they take out the quicker they run. I have a friend that had a 400 in a camaro. He started out with 4.56s and backed up one step at a time all the way back to 3.36s and got quicker with each gear change.
If you have an all out race setup this may not apply,but if you're dealing with a street setup you would be suprised how many times it does.

[Dave Severson]

I guess so, I just love the hard launch and good 60 foot times the the deep gears give. Why the soft launch??? I always like the thing to hit so hard your eyes cross....

[JSracing]

Originally posted by riverhorse59
Dave , I was thinking something simular to JS Racing. Maybe he was running out of cam and or motor. It's no use running 4.88s or 5.13s unless you have enough motor to pull all the way thru the quarter mile.
I have seen a lot of people run too much gear with a short rod 400 small block chevy. Then they wake up and find out the more gear they take out the quicker they run. I have a friend that had a 400 in a camaro. He started out with 4.56s and backed up one step at a time all the way back to 3.36s and got quicker with each gear change.
If you have an all out race setup this may not apply,but if you're dealing with a street setup you would be suprised how many times it does.

Well actually, very light race cars with very good torque, start to need less gear, like a street car. It's funny, I've heard all my life that you need tall gears and an eight inch convertor like the real race cars do to go really fast. Now that I get there I find out thats good up to a point, then you go back the other way, 9 inch convertor and less gear.

Some how I don't think "running our of motor" is why I changed. LOL

[Dave Severson]

OK, the converter deal. Not up on them at all. I still like my 5 speeds, and yes I know they are not near as consistant as a glide. The automatic tranny world is a place I seldom venture, but what you say makes a lot of sense.

[JSracing]

Originally posted by Dave Severson
I guess so, I just love the hard launch and good 60 foot times the the deep gears give. Why the soft launch??? I always like the thing to hit so hard your eyes cross....

I would agree but there is a point when it is too hard, blows the tires away and you have to peddle the car.

Not sure about running out of cam, I guess anything is possible. We run eigth mile mostly. I didnt do it because the car isn't pulling up top, I did it to calm the launch down. I also added some wheelie bars.

Cam specs: I= 796 285@ 50
E= 761 292 @ 50