Improving quarter mile time advice please?!

[richierich]

Hi all. Had my Oval out on the quarter mile and need some advice. Car is a full weight 56 Oval running a 2110 type 1 motor. Motor puts out 177hp at the flywheel and I have a KCR Super Street transmission with stock ratios. Rear tyres are street tyres - 205/65/15's.

I ran:

15.0 1/4 mile at 87mph;
2.08 second 60ft;
9.68 1/8 mile at 69mph.

This engine has run the 1/8 mile previously at 7.04.

What can I do to improve these times and i assume its my 60ft that is killing me. How do I improve it?

[ps2375]

[richierich]

[ps2375]

Tires and driver, may not be in that order, but those are the main culprits.

[jpaull]

Need some details about the cam, heads, valve sizes, porting, carbs, and also where ya at?
_________________
[email protected] MPH 1/4 Mile & 8.1 @ 83.7MPH in 1/8 Mile with Mild Type 1 VW Mag Case 2234cc commuter engine in stock weight bug w/only .491 total lift(CB2292 Cam), 42x37 heads, 48idf's, Street tires, Belt on, Mufflers, Pump gas, video of the run here: https://youtu.be/M3SPqMOKAOg

Transmission by MCMScott:
Rhino case, Klinkenberg 4.12, Superdiff, 002 mainshaft with 091 first idler. Weddle 1.48 Third & 1.14 Fourth.

[vwracerdave]

What R&P are you running? 2.08 60' time sounds about right for those size street tires.

[richierich]

I'm running:

SCAT C45 cam;
Mofoco 050 heads with 42×37.5 valves;
EMPI 48 IDA's on tall manifolds polished and match ported;
1 5/8 Merged header;
Stage 1 Kennedy 1700lb clutch plate;

Also, I'm at Sea level.

R&P is a 4.12 Klingelnberg

[[email protected]]

In what way did you get the 177? Is this an actual dyno number, or a mathematical estimate?

What type of fuel pump are you running?

Do you have any type of launch rpm limiter to monitor what rpms you're at?

[richierich]

[[email protected]]

Was the dyno run with this exact pump? I would say the fuel pump is one of the problems. A friends 2276 with 44's ran out of fuel about 700 ft with one of the rotary carter pumps. I would look into a much larger pump. We put a Red Holly on the previously mentioned car, and it was a completely different animal. And have at least a 3/8 feed line from the pump.

Having some type of rpm limiter can help tune your launches. My 2180 lb Super with a 1776 will considerably change 60 ft times with as little as a 200-300 rpm change from its 3800 rpm sweet spot.

[Chip]

[jpaull]

Are you running 1.1's or 1.25's? The C45 cam is really mild. Even with 1.25's the lift is only at .490.

Next, Those Mofocos. Are the ports opened up much? any pics of the intake ports? Really this will determine if you can go up on your cam or not.

You need more cam AND/OR portwork on those heads.

I would not base anything on the Dyno Horsepower. Its a great tool. All we know is that you need MORE.

[74 Thing]

That HP figure seems high or optimistic

What were your tire pressures-prob need to go much lower with street radials.

Seat time and lots of tuning are always the key.

What did your car weight with the driver?

[[email protected]]

For now, why don't we use his 177hp as a constant factual variable, and not second guess/discredit the build. I can possibly see that the conditions/environment with the engine mounted in the car, might not be duplicated from the dyno session from my question about the fuel system. If there are issues with the fuel system, or even the charging system not alowing this engine to produce the full 177, that's fine, but lets assume it made the claimed 177 on a dyno.

Tire pressures as others have mentioned can have a huge effect on 60 ft times as well. From my experience, a fully treaded radial tire will not usually increase traction below 15 psi, but it will be unstable at speed below 15. Experiment with 15-20 psi.

I would also create some type of rpm limiter to be able to adjust the rpm as the clutch is released upon the launch. My experience in drag racing has been to limit as many uncontrollable variables you can, an attempt to turn them into controllable/tunable variables. Any adjustments made to the suspension/tires will be difficult to see their effect if one time you launch at 2000 rpm, and the next at 4500.

[air-h2o-air]

the easiest way....get rid of those big rear tires for starters


when staging....load trans using parking brake as you light the 2nd bulb

Use E brake as your line lock...use your feet to work throttle and clutch

slip clutch and apply throttle gently....dont go WFO on throttle and side step the clutch upon the launch

[vdubnut58]

For starters I would order a set of drag radials. Do you have 135's up front?
I would remove the belt before your pass. And buy a Braile race weight battery. I assume your suspension is stock so after the car starts to hook if it's lowered your sump and muffler will drag on the starting line so you might want some 28mm rear torsions. I would leave the motor alone and focus on the car. First pass I ever made in my car was a 13.4 and I was able to get it to it to 12.60 without making any changes to the engine/Trans. I even picked up a set of T bars in place of the bumpers. There are lots of little tricks to be found.

[richierich]

[madmike]

Get Slicks
_________________
'Black Ice'Drag Buggy 'Turbo'
Rail Buggy 1915 turbo
76 Drag/Street bug 2180cc 'Turbo' 11:85 @113 mph"If I go any faster I'll burn up the Hamster" ,gets 28 mpg. also 10/09/22 11.90 @115 mph
"If I'm ever on Life Support,UNPLUG Me, Then Plug me back In see if that Works"

[[email protected]]

I am taking your dyno info as fact, I would just rather others would as well. I have seen where an engine performed well on a dyno, but had issues in the car. Using a stock 6mm line in the tunnel that could not supply enough volume of fuel, and poor charging systems not creating enough voltage/current for the ignition system at higher rpms have been two of the most common things I have seen.

For every modification there are effects on other things, some good, some bad. If you change to a different tire, the rest of the car needs to be able to work with the different tire. Is your trans a Superstreet with a 3.80 1st, or a Superstreet Plus with a 3.78 1st? Do you have a better form of torsion bar grommet, such as urethane, or one of the bronze bushing covers? Do you have some type of mid mount to capture the front of the trans? Do you have some sort of heavier aftermarket axles? Those are all things to consider that can have serious concequences when switching to a drag type tire?

Call around to scrap yards, or garbage dumps to see if they have a scale that would go down to a 1000lbs., or so, and see if they could weigh your car.

[richierich]