Nice write up, can't belieive how clean that car is.
Taking Adam's point on cams, the Comp cams Extreme energy series XE262H will likely go nicely with that motor depending on the rear gears e.g 3.23 or deeper. Still give good vacuum for the brakes too as well as liking stock convertor and manifolds.
Back to Stock - 73 Challenger Rallye
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Thanks for the feedback Ivor, Adam, Miles, this is what I need.
Adam, it's all stock so according to the workshop manual the compression ratio should be 8.5:1. I'm going to be running the stock dual plane iron intake and the Carter Thermoquad 4 barrel carb. Also power brakes, air-con and 3.55 diff ratio.
Miles, I don't think I can go with the Xtreme Energy cams as they require an adjustable valve train and machining to the heads?
The Comp Cams I'm looking at are these:
http://www.compperformancegroupstores.c ... =LACAMHFHE
And in particular, this one:
http://www.compperformancegroupstores.c ... =LACAMHFHE
These have a lobe centre of 110, but I've just noticed that the notes say stock springs can't be used. So I might be better with this one:
http://www.compperformancegroupstores.c ... =LACAMHFHE
Opinions???
Adam, it's all stock so according to the workshop manual the compression ratio should be 8.5:1. I'm going to be running the stock dual plane iron intake and the Carter Thermoquad 4 barrel carb. Also power brakes, air-con and 3.55 diff ratio.
Miles, I don't think I can go with the Xtreme Energy cams as they require an adjustable valve train and machining to the heads?
The Comp Cams I'm looking at are these:
http://www.compperformancegroupstores.c ... =LACAMHFHE
And in particular, this one:
http://www.compperformancegroupstores.c ... =LACAMHFHE
These have a lobe centre of 110, but I've just noticed that the notes say stock springs can't be used. So I might be better with this one:
http://www.compperformancegroupstores.c ... =LACAMHFHE
Opinions???
Martin Walker
Should be good for around .500" dave , good point all the same.
With a low comp motor & the piston down the hole around .300" , would be thinking of a short duration with a tight lobe sep , this will close the intake sooner building higher cylinder pressure , if you go with a wider lobe sep you could advance the ICL (8*) , in doing so it will close the intake valve sooner , build higher cylinder pressures (dc) helping with the low CR , getting the best of both worlds regards vaccume & reversion @ idle , before anyone pipes up regarding PV clearance , don't think they'll be an issue considering how far the piston is down the hole.
Another HP gain would be to fit higher ratio rocker arms , increasing VE but at the same time not effecting duration (maybe 3* ) , tis a win win situation , there's many ways to skin a cat , just a couple of ideas thrown out , possibly annialating any stock motor off the lights.
With a low comp motor & the piston down the hole around .300" , would be thinking of a short duration with a tight lobe sep , this will close the intake sooner building higher cylinder pressure , if you go with a wider lobe sep you could advance the ICL (8*) , in doing so it will close the intake valve sooner , build higher cylinder pressures (dc) helping with the low CR , getting the best of both worlds regards vaccume & reversion @ idle , before anyone pipes up regarding PV clearance , don't think they'll be an issue considering how far the piston is down the hole.
Another HP gain would be to fit higher ratio rocker arms , increasing VE but at the same time not effecting duration (maybe 3* ) , tis a win win situation , there's many ways to skin a cat , just a couple of ideas thrown out , possibly annialating any stock motor off the lights.
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Martin,
That cam i sugested i have run with stock springs. I hace also run it with the correct springs with internal dampers. No need to macine the heads and it cleared the valve stem oil seals no probs. i didnt use adjustable rocker gear when on my 318 either.
As Adam points out, the low duration of the cam helps with lower compression and cylinder pressures.
choices, choices, eh
That cam i sugested i have run with stock springs. I hace also run it with the correct springs with internal dampers. No need to macine the heads and it cleared the valve stem oil seals no probs. i didnt use adjustable rocker gear when on my 318 either.
As Adam points out, the low duration of the cam helps with lower compression and cylinder pressures.
choices, choices, eh
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- Posts: 7309
- Joined: Fri Nov 04, 05 8:40 pm
- Location: Cornwall
No to power brakes, but vacum was good. Cant remember exact figs, but put a vac guage on at idle and I think it was around 14 if memory serves me well
Tick over was smooth with just ahint of a lope, nothing drastic and would sit in gear at 800rpm fine.
Gareth and Stu are fitting that same cam to their 318, might be worth talking with them once its all together
Tick over was smooth with just ahint of a lope, nothing drastic and would sit in gear at 800rpm fine.
Gareth and Stu are fitting that same cam to their 318, might be worth talking with them once its all together
As it rained on and off all day Saturday I had to wait until Sunday before I could continue with preparation of the engine bay. There wasn’t much left but removing the steering column took longer than I expected. When I restored the dashboard some years ago I made up a tool to remove the steering wheel but I have no idea what’s happened to it.
After fabricating another tool from a couple of bolts and a piece of steel plate the steering wheel was safely off. As I removed the steering column I had a chance to re-acquaint myself with the wiring under the dash and the extra bits I’ve added over the years, some of which won’t be going back in (electric fuel pump for one).
Next to come out was the brake master cylinder and power servo along with all the brake pipes, proportioning valve and linelock. I think the linelock is one modification I will leave on the car, it’s too much fun to lose it.
The braided fuel hose was all that was left to remove apart from a few clips which I’ve left for the time being and now it’s all ready for a good degreasing and clean next weekend.
After fabricating another tool from a couple of bolts and a piece of steel plate the steering wheel was safely off. As I removed the steering column I had a chance to re-acquaint myself with the wiring under the dash and the extra bits I’ve added over the years, some of which won’t be going back in (electric fuel pump for one).
Next to come out was the brake master cylinder and power servo along with all the brake pipes, proportioning valve and linelock. I think the linelock is one modification I will leave on the car, it’s too much fun to lose it.
The braided fuel hose was all that was left to remove apart from a few clips which I’ve left for the time being and now it’s all ready for a good degreasing and clean next weekend.
Martin Walker