Unilite Distributor

TVRTASMIN · Post by **TVRTASMIN** » Wed Jul 18, 2007 7:24 pm

I'm starting to aquire parts etc to build a Rover V8 using a 3.5 Range Rover stiff block as a base.
I have standard SD1 heads.

What advantage is there using a Mallory Unilite distributor with a quoted 24 degrees of advance @ 3200 RPM over using a standard Lucas distributor with Pertronix ignitor.

r2d2hp · Post by **r2d2hp** » Wed Jul 18, 2007 7:38 pm

From Experiance, absolutely none - over rated in my opinion. I have reverted back to the standard item and sold my Unilite, it also sticks up a lot higher than standard

Post by **Coops** » Wed Jul 18, 2007 8:03 pm

and i disagree.
mine runs better with the unilite than it did with the standard dizzy,
i then upgraded to a mallory cdi unit to go with the unilite.

TVRTASMIN · Post by **TVRTASMIN** » Wed Jul 18, 2007 8:13 pm

I suppose it all depends on the condition and set up of your original /replacement distributor as to any outcome.

If you were to replace a tired one with a new one then i would assume even using a standard replacement would offer a big improvement, or if the full potential of something like a Mallory coil is not exploited and set up properly then i can see a problem there.

r2d2hp · Post by **r2d2hp** » Wed Jul 18, 2007 9:26 pm

Just take a look around at those producing good HP, not many use a unilite. Its a total waste of money.

If your going to spend that sort of money look else where.

Unilite will make little difference to the later type dissy, and as for the Mallory CDi is not compatible with the 14CUX ecu without a fudge.

Have to say it made not one iota of differance when I tested on a rolling road, in fact the advance curve of the Unilite was incorrect.

Ian S, if your around think it would be good for you to comment as we discussed this some time back.

Post by **Coops** » Wed Jul 18, 2007 9:42 pm

every one to there own reg,
next you will say that msd is a waste of money to

r2d2hp · Post by **r2d2hp** » Wed Jul 18, 2007 9:48 pm

Funny you should say that. In conjunction with the 14CUX it is.

Have you had yours setup on a rolling road and done the comparison - think you would be surprised at the results.

Give Bill a call and see what he recommends, am damn sure it wont be a Unilite.

Seem to remember spare parts can be hard to come by as well.................

Post by **Coops** » Wed Jul 18, 2007 9:52 pm

no point as im going mapped ignition end of this year,
and like i said on my set up it made a difference, not every one will be the same.

r2d2hp · Post by **r2d2hp** » Wed Jul 18, 2007 9:57 pm

Maybe its because you dissy was knackered to start with, all I am saying is that compared to a good unit it makes no differance. If you have that sort of money to spend look else where.

You pays your money and makes you choice - do it wisely.

TVRTASMIN · Post by **TVRTASMIN** » Wed Jul 18, 2007 10:05 pm

OK. At this stage i do not intend to go 14CUX. I've had Range Rovers and TVR's with this set up.
If i was to go down the Fi route it would be Megasquirt controlled.

I fancy a change, so i'm using an Edelbrock 500 plus Performer manifold.
I don't want to exceed 4.5 litres or go silly with camshaft lift so something like a 4.3 with Crower 50232 cam.
I have two sets of heads, one pair SD1 the other Range Rover. Both 3.5.

I think this is the area which is going to cause the most hassle, should i stick with a reasonably well ported set of 3.5 heads or go for some 3.9 mildly modded ones, although i've heard the 3.5 heads are better with the 4.3 conversion.
I've been watching heads on Ebay this week but i'm a bit wary as you have no guarantee they are going to be any good or what they are described as.
Anybody got a decent pair of modded heads for sale.
Saw the Merlin heads but i've been down that biggest and most expensive must be best route before.

Post by **Coops** » Wed Jul 18, 2007 10:17 pm

there are other ecu's out there,
i know the majority on the forum use megasquirt, but i use and now so do a few others on here the vems ecu. so keep your options open mate,

Post by **katanaman** » Wed Jul 18, 2007 10:23 pm

3.5 heads are the same as 3.9 heads assuming have 3.5 heads from SD1 on.

x.l.r.8 · Post by **x.l.r.8** » Thu Jul 19, 2007 5:18 am

My opinion for what it worth is that you cannot get better then the standard dizzy................on a standard engine. If you increase performance of ANY engine you are basically squeezing more fuel and air mixture into the available space and trying to ignite the mixture, this increased mixture will dampen the spark (or if the plug has not cooled enough or the rest of the engne is not also tuned to make this work you will probably end up with a hot spot and pre-ignition will occur).
If your doing this with the standard set up you have the wrong tool for the job, most people improve the volumetric effeciency of an engine then claim great results when finally getting around to upgrading the most important part of the system.
A basic setup only needs livening up the original system, hence why I came up with my frugal upgrade. After that your into the relms of finding a signal scorce (a late dizzy does this very well) a decient amplification module and a good quality coil. All to often this is taken on as a job lot, the end result is some pretty impressive improvements. You may well reach the same conclusion with only 1 or 2 of the above components but in for a penny, as they say.
Nitrous yet again distorts the truth because yet again the use of a cooler plug is required, again taking you away from the engine your standard ignition system was designed to deal with.
Now if you really want to end the discussion go for a crank trigger backed up by a trigger on the flywheel to eliminate crankshaft torsion and have 8 coils.
As I said just my opinion.

TVRTASMIN · Post by **TVRTASMIN** » Thu Jul 19, 2007 7:14 am

So i have now made the decision to use a good standard dizzy, which type should i go for.
When you mention late type, is this the unit as fitted to the serpentine engine?

x.l.r.8 · Post by **x.l.r.8** » Thu Jul 19, 2007 2:06 pm

Again this is only my opinion, I would look for the dizzy that only generates a signal, that would be the one in the first sticky in this section. Make sure it has NO play in the shaft, and check the bottom gear for wear or cracking, also if you can see it running, put a timing light on it and make sure your advance is working, then ensure the rotor can turn about 15-20 degree's and return without binding. If it has the black amplifier on the side of the dizzy, either replace with something better or at the very least move it to a cool place away from the thermostat housing, for some unknown reason there was less interference on the scope when mounted near the coil. I guess thats why some of the systems had the amplifer bolted to the coil?.