Mopar Muscle Association UK

As per the other thread, we warmed up the Barracuda with a bit of spray.

Originally it was going to be an old school Tunnel Ram car, but we could not get it to start, let alone run.

We ditched the TR in favour of an Edelbrock Super Victor MW 4-bbl inlet to match the Edelbrock Victor MW heads.

When we put the Inlet on, we thought it would be rude not to add the nitrous system at the same time. I designed and instaled it all in about 3 hours and it shows in terms of neatness but it works....

In view of time (and previous experience) we opted for simplicity.

As the motor was already 12:1, we had to be quite careful and also the fact that the ringswere not gapped very large.

We decided to run 100 shot in the first instance, and we will cap it at a 150 shot. We do not want to have to sweep up another engine quite so soon.

Therefore, I installed it so that it was idiot proof (Roydon was driving).
A single "Arm" switch provides the power and cut off to a WOT microswitch on the carb. In line with this was placed a low fuel pressure switch. One of these saved our bacon on the old engine when a fuel solenoid failed.

This "chain" provides the trigger to the Nitrous and Fuel Solenoid.
A separate circuit via a relay was installed for the purge.

A simple 4500 spray plate was used and the jets table was reversed so that a greater proportion of Nitrous was added than Fuel. We have found this cuts down the chance of off the line bogs and ring damage from excessive unburnt fuel collecting in the Lands.

To off-set this we will retard the locked out ignition by 5 degrees as a result of a built in feature on the MSD Digital 6 unit.

The pick up was impressive. It had a different reaction to the old Plodge engine. The old engine was a torque monster that was great on the line but with no top end due to lack of Port Flow.

In the case of the MW engine, it had bags of Flow (and therefore Horsepower) but was not great off the line. Using the nitrous helpd this and this meant it could then pull the revs at the top end. Result.

We have done limited tuning (none!!! ) so I think we can get another 8mph out of it and improve the 60ft times - these will never be dramatic due to the gear / tyre combo to pull the mph but we hope to get to 1.50 60 foot times to get to around a 9.5 ET.

If not then lots of humble pie later on at the HRD's!!!

Pete

I should add that we were incredibly lazy on the fuel installation, whilst being aware of the risks. We previously ran a separate AN-6AN system with Pump, filter and regulator and return (I don't like to dead-head stuff..)

However, as the car was going to have a Tunnel Ram, we had installed a BIG fuel log and a HUGE Aeroquip Pump and Filter.

As we knew we had lots of fuel flow and lots of fuel pressure, we blanked one port off and linked the last spare Log port to the input of the Fuel supply Regulator for the nitrous set up.

NOT Recommended on a basic installation but we have lots of gauges and adjustment points to ensure robust pressure on the fuel side of the nitrous set up (and we have the low pressure sensor............)

That somehow sounds very clever and technical but a right lash-up at the same time!
Best of luck with it mate

why the purge nesasicty spelling awefull i know

You need pure nitrous at solenoid not nitrous air mix

Jon Connolly wrote:You need pure nitrous at solenoid not nitrous air mix

thought so ta

Cannonball wrote:why the purge nesasicty spelling awefull i know

You need to ensure the Nitrous line up to the Solenoid has no air in it so it fires safely and correctly.
The Purge solenoid is located very close to the Nitrous soleniod.

You also need it to clear the line when you turn the bottle off and want to empty the line of Nitrous when you have finished using Nitrous....otherwise BIG shock if you inadvertently hit WOT!!!

We also installed a bottle warmer, but it was so hot at the Nats the bottle stayed at 1000psi after 2 runs........

Pete wrote:

Cannonball wrote:why the purge nesasicty spelling awefull i know

You need to ensure the Nitrous line up to the Solenoid has no air in it so it fires safely and correctly.
The Purge solenoid is located very close to the Nitrous soleniod.

You also need it to clear the line when you turn the bottle off and want to empty the line of Nitrous when you have finished using Nitrous....otherwise BIG shock if you inadvertently hit WOT!!!

We also installed a bottle warmer, but it was so hot at the Nats the bottle stayed at 1000psi after 2 runs........

pete have you ever done a static test ie ie helld the throttle at 3000 rpm then pressed the micro switch to see how much the rpm,s climb ???? we were advised to try this the revs came up 4-500 so we assumed we had the flow but up the track bassicaly nothing as the weather was so hot a mtr pass yielded 10.90 with what we thought was a 100 shot 10.70 but no improvement on mph ???? the car runs 10.70 best no gas with good air,

Pete wrote:

Cannonball wrote:why the purge nesasicty spelling awefull i know

You need to ensure the Nitrous line up to the Solenoid has no air in it so it fires safely and correctly.
The Purge solenoid is located very close to the Nitrous soleniod.

You also need it to clear the line when you turn the bottle off and want to empty the line of Nitrous when you have finished using Nitrous....otherwise BIG shock if you inadvertently hit WOT!!!

We also installed a bottle warmer, but it was so hot at the Nats the bottle stayed at 1000psi after 2 runs........

hence THE REASON THAT I HAVE A STEERING WHEEL BUTTON AFTER THE THROTTLE SWITCH SO YOU CAN INADVERTENTLY HIT THE GAS BY MISTAKE....sorry for shouting

what was the bottle pressure Dunc ?
I sometimes just tap the button to purge the gas in the burnout...as no purge valve fitted YET

mental but it works

One thing worth checking is actual fuel pressure with a calibrated guage ( cheap from Ade Worman plumbing shop ) ... my Holley reg and guage used to read 9 psi and it turned out to be 4 psi.

I changed to an Aeroquip pressure reg and the fuel side could be set up accurately.

I also used a thumb button so I knew it was definately activated.


Different people do different things

AllKiller wrote:what was the bottle pressure Dunc ?
I sometimes just tap the button to purge the gas in the burnout...as no purge valve fitted YET

mental but it works

bottle pressure was 950

Sorry to jump in chaps.
But am I correct believing that the gas switch is activated at full throttle only like a " fogger" system ?
Or are we talking progressive ?
Sorry. Used to bike set ups so a bit lost on some bits !!

As it was only ever intended to be a small shot we did not go with progressive, but I do have a progressive nitrous controller if required...............All in on the line - that's the way!!!

Duncan

This is the tune I used for a 100 HP shot

99 Shell V power

Single dead head fuel pump tee`d to 2 pressure regs

6.5 psi to carb

5.5 psi to nos

47 jet to nos

53 jet to fuel

750 double pumper jetted to 72 / 72

No 7 plug gapped to 0.028

34 deg timinig retarded by 5 degree with a window switch opening at 3000

Low pressure fuel switch in series with nos solenoid

Launched at 3500 with nitrous thumb button on

490 HP at crank

2583 lb race weight at the tree

10.24 sec @ 128.09 mph .... 1.4561 sixty foot

Every car and driver is different but the above worked for me ... hopefully it may help ???

Here`s a pic of the plumbing side with vent solenoid on its side as close to nos solenoid as poss