v12 cam and distributer questions.
#1
v12 cam and distributer questions.
I just recently picked up a v12 from an 85 or 86 xjs convertible with around 68k miles on it. Working on tearing it down to the short block to look everything over since it sat for a long time and to replace gaskets. I am going to be putting it into a 1984 Mercury Capri that I have. Was wondering how the rotor comes off of the distributer. And are the 3 allen head cap screws at the bottom of the distributer what hold it to the engine?
Looking at possibly getting the stock cams reground and wondering if anyone has used Delta cam before. Looking for kind of a hot street cam. I will be porting the heads. Maybe look for a set of flat heads if I can get a set with pistons for a good price but probably stay with the HE heads..
Looking at possibly getting the stock cams reground and wondering if anyone has used Delta cam before. Looking for kind of a hot street cam. I will be porting the heads. Maybe look for a set of flat heads if I can get a set with pistons for a good price but probably stay with the HE heads..
#2
The rotor just slides off, can require quite a bit of force. I used a screwdriver under the bottom of the rotor and turn it sideways to prise it off.
Yeah, you should be able to pull it after removing those lower screws. The sensor wheel comes off with a snap-ring and the outer shaft has a screw in the middle ( I think phillips) that has a bushing that always goes bad.
Clean the cams well and check the vacuum advance is functioning. Pretty damn simple distributor since its electronic.
Yeah, you should be able to pull it after removing those lower screws. The sensor wheel comes off with a snap-ring and the outer shaft has a screw in the middle ( I think phillips) that has a bushing that always goes bad.
Clean the cams well and check the vacuum advance is functioning. Pretty damn simple distributor since its electronic.
#3
The HE makes more torque and has a flatter curve than the flat head, if you are after a good street engine the HE will be ok, if you want screamer and high peak HP 7500+ then flat heads will be needed.
Be careful when you port the heads DO NOT open the ports too much or you will kill power, in a 5.3L the ports are probably already too big. Power can be made by a good set of intake and exhaust manifolds.
I am building a 6.7L V12 ATM and here is the link. It details what I have done with the heads. You could do similar without opening the chamber as much as I did, just unshroud the intake valve.
https://www.jaguarforums.com/forum/x...-build-170908/
Be careful when you port the heads DO NOT open the ports too much or you will kill power, in a 5.3L the ports are probably already too big. Power can be made by a good set of intake and exhaust manifolds.
I am building a 6.7L V12 ATM and here is the link. It details what I have done with the heads. You could do similar without opening the chamber as much as I did, just unshroud the intake valve.
https://www.jaguarforums.com/forum/x...-build-170908/
#4
Thanks for the info. I tried pulling the rotor off with some pliers and when it didnt budge I was thinking maybe something else held it on. Guess I need to just try harder. I have also thought about doing a low boost turbo setup so if the chamber gets opened up a decent amount and drops the compression ratio that would probably be a good thing.
I have been following your build thread and thats what prompted me to post here.
I have been following your build thread and thats what prompted me to post here.
#5
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#6
Me too. Also OP, it is VERY important NOT to pull upwards on the rotor, as this can break delicate parts at the bottom of the dizzy. Just rock the rotor with one hand each side, and if it will not budge, dremel the plastic where it fits over the shaft.
#7
Thanks for the info. I tried pulling the rotor off with some pliers and when it didnt budge I was thinking maybe something else held it on. Guess I need to just try harder. I have also thought about doing a low boost turbo setup so if the chamber gets opened up a decent amount and drops the compression ratio that would probably be a good thing.
I have been following your build thread and thats what prompted me to post here.
I have been following your build thread and thats what prompted me to post here.
Opening the 5.3L heads up to 29cc (same as the 6.0L) will drop CR to about 9.3:1 - 9.7:1 depending on which pistons you have ie crown volume (dish).
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#8
I just recently picked up a v12 from an 85 or 86 xjs convertible with around 68k miles on it. Working on tearing it down to the short block to look everything over since it sat for a long time and to replace gaskets. I am going to be putting it into a 1984 Mercury Capri that I have. Was wondering how the rotor comes off of the distributer. And are the 3 allen head cap screws at the bottom of the distributer what hold it to the engine?
Looking at possibly getting the stock cams reground and wondering if anyone has used Delta cam before. Looking for kind of a hot street cam. I will be porting the heads. Maybe look for a set of flat heads if I can get a set with pistons for a good price but probably stay with the HE heads..
Looking at possibly getting the stock cams reground and wondering if anyone has used Delta cam before. Looking for kind of a hot street cam. I will be porting the heads. Maybe look for a set of flat heads if I can get a set with pistons for a good price but probably stay with the HE heads..
The reason you won’t buy cheaper than that is the work required to pull that engine and dismantle it. At a minimum you are looking at 10 hours of labor.
The good news is you can often sell other parts to further reduce your costs.
You’ll want the distributor too. The pre HE engine “Flathead” has a better advance curve. Allowing a total of 38 degrees rather than the restricted 17 degrees of the Pre HE.
I tap out the sleeves too and keep the pistons with their bores. Because of the short stroke it’s rare to see any serious wear on them.
Regarding camshafts. I’m not familiar with Delta. Both Kent and Piper offer reground camshafts in England as does Isky and Crower in America.
The specs on the Piper and Kent are fractionally better (Maybe 2-3 hp ) than the Isky and Crower but are twice as expensive. If this is to be used on the street. Realize all camshafts are a trade off. Yes they make more power at higher RPM’s but do nothin at lower drag race from the stop light rpm’s. The power comes on ( depending on which grind ) above 5000 rpm.
Cheap EBay turbo chargers are a great temptation. But you need two unless you have a lot of space for tubing to run one bigger one. There the loss due to length of tubing required plus the cost of that tubing make two better than one.
Next realize the the stock EFI cannot be changed like newer systems. It’s an old analog while modern systems are Digital. Yes you can buy the hardware to get it running rather cheaply. But then you’ll need the wiring, a lap top to tune it. And most of all a lot of patience and time to get everything running smoothly and at peak.
Megasquirt is a self learning system at a reasonable cost. ( yet still needs tuning to optimize performance). But if you want full performance spend the extra and get the Megasquirt gold.
Boosted air heats up. So you either deal with it via intercooler, or with fuel. Here in America we have E85 think of it a racing gasoline from the pump.
The greatest thing about it isn’t the extra power it makes. It’s the cooler charge generated. You can safely go above 10 psi with stock components in the engine.