Mopar Muscle Association UK

AFAIK all changing the spring does is effectively recirculate more oil - in other words you'll see less oil pressure but you'll still be pumping the same amount, just dumping more back to the pan. Even that costs horsepower! Anyway, I'm assuming the oil pressure will drop a little as the engine loosens up over the first few thousand miles.

Gotta love those cross rams eh, those Chrysler Engineers weren't fools!

We're in real danger of getting this car back on the road before the winter sets in, should even be ok for Duxford, if not the Hot Rod Drags... tho that's not a nice journey from here in the Satellite, let alone the Polara!

Dyno session was finished off last Saturday, once we'd finally got the calibration kit from JWR. Paul went up on his own and spent another full day with Kenny getting the Carters running right. Didnt manage to test the max wedge 'headers' cos it got too late but did get the most out of the carters with the full set of springs & jets. Best results were obtained at 38deg total timing!
Shame cos it would have been good to see how much power was lost fitting the old manifolds - swapping headers for stock manifolds can result in around a 70hp loss in a 450hp+ engine (so I'm told) but our manifolds are a darn sight better than later stock RB manifolds. We might even have seen an improvement in torque as the dyno headers were a bit on the large side at over 2" dia.
Slight disappointment was that we didnt see that much of an improvement over the lashed up single 4bbl used in the 1st session.
Torque was up by 15lb-ft at 472 but max power seen on the day was down by 2hp at 448

BUT.... looking at the figures, in the 4bbl test the 450hp was at 5400, and the test limited to 5500 by which time it had dropped off to 448. Not much, granted, but dropping off all the same.
The latest test was 'limited' (ie thats as far as they went) to 5600 and power was still rising so would undoubtedly have passed 450 by 6000rpm
Thats what I reckon anyway...
AND.... I wouldnt be suprised if the original manifolds helped power or torque as that's what the intake setup was designed to run with. That's my un-educated opinion anyway
That was all on super unleaded. They did try some 113 octane but didnt see any improvement. We'd have to up the comp ratio from 10.2 back to more like the original 11:1 to make the most of that, but our aim was to run on pump gas without detonation, which we've achieved, so we'll make do for now

This graph is from the run that gave the above numbers - you can see the power is still on the up. Not sure what the glich at 5300rpm is - maybe Kenny sneezed as he was applying the throttle
The other dip in the graph at 3700 is what Kenny attributes to the dyno's headers being a bit too big. The original manifolds should smooth that out.

Well done boy's, power to the Roarin 60's

Good work, looking forward to seeing how it does in the 1/4 now!

Nice work lads.

Should look nice at it's debut at Duxford

Thanks guys, cant wait to see if the rebuilt trans & the new brakes work just as well...... sure they will tho, eh Blue

dont put the mockers on it Alex!! I know I said we should be ok for Duxford ... but I thought we'd have the car at the 1st one so I'm no judge

Oh, and we'll be leaving the oil pressure as it is. I'm told "oil pressure is like money, better to have too much than too little... it is good for the BB mopar"

Well done Rob & Stu,looking forward to seeing it.I take it you'll be seeing alot more of me in the rear view mirror,when you hoof it down the m1/m25.

Adam68 wrote:Well done Rob & Stu,looking forward to seeing it

me too Adam , dont think I've seen the car since just after Xmas
Hope I can remember how to drive it, if Stu lets me

Adam68 wrote:I take it you'll be seeing alot more of me in the rear view mirror,when you hoof it down the m1/m25.

I'll try not to get too far ahead, dont want you getting lost again

Brilliant car lads!

Remember it at the Nats the other year and had no idea it was yours!

Cant wait to see it!
Mark

RobTwin wrote:Oh, and we'll be leaving the oil pressure as it is. I'm told "oil pressure is like money, better to have too much than too little... it is good for the BB mopar"

Not necessarily, if it's too high it can cause other problems. Only thing is how do you judge what is too high on any particular engine. Even engines that are supposedly the same are slightly different. I'm sure Alex and Dave could elaborate on some of the problems of too much oil pressure can cause better than I can.

Yeah, I thought I was opening myself up there for a heated (not mass) debate but I was quoting the guy that built one of the engines for the recently restored/recreated Olympic Charger that ran in the Historic LeMans race.
He's been working on and racing cars & engines like ours since they were new so certainly knows a whole bunch more than me...........

...... but prob not as much as Alex & Dave

I remember (way back in '87) when our Satellite's engine was finished and started using it, noticing the oil pressure was high (in the 90's I think), so took the car back to Clive Bond who changed the spring to reduce it.
It still runs at 70psi at 3000prm.

I have no idea what the effect of too much oil pressure would be!

I have never come across that problem before.

A dip in the torque curve at around 3500rpm is quite common. Are these hydraulic lifters?

Oh and I don't think you are far off peak power there. I think the curve would have peaked just over 450hp. But peak HP really depends on how fast that torque starts to fall off. I think it would be dropping fast by 6000rpm.