Camshaft changes.
Discussion
I'm having my Griff engine (pre-serp 5.0l) rebuilt at the moment and am thinking of changing the cam while it's stripped down, so I'd be interested in what views people have regarding some of the after market cams, i.e. which cams they are running and engine/performance changes, driveability etc. The engine will be standard other than this change.
Thanks in advance.
Thanks in advance.
Hi
I can only quote the seriel # of the cam that is in my Griff from new , it is a Kent 7845bdk/29 it is a high lift performance cam , and there is a huge difference , although I have driven a few Griffs and now wonder if that extra spine breaking performance is really worth it. The day to day driving of the car is rough to say the least, the idle is lumpy and trying to keep at 30mph in 4 th gear is impossible . Oh but when it is revved in anger then it is awesome. One of the reasons it went back to the factory was because of the uneven running at low loads it was there they identified the cam, the only cure change it for a "standard "one" so some advice think carefully befor changing.
best regards and I hope the build is sucessful
Simon
I can only quote the seriel # of the cam that is in my Griff from new , it is a Kent 7845bdk/29 it is a high lift performance cam , and there is a huge difference , although I have driven a few Griffs and now wonder if that extra spine breaking performance is really worth it. The day to day driving of the car is rough to say the least, the idle is lumpy and trying to keep at 30mph in 4 th gear is impossible . Oh but when it is revved in anger then it is awesome. One of the reasons it went back to the factory was because of the uneven running at low loads it was there they identified the cam, the only cure change it for a "standard "one" so some advice think carefully befor changing.
best regards and I hope the build is sucessful
Simon
Listen up folks, there are a lot of irritable Griffs out there, mine was one of them and there is a cure, see here
www.pistonheads.co.uk/gassing/topic.asp?h=0&f=23&t=70243
My car, for the first time, feels like it's performing the way it was intended, it is smooth and well mannered, when it comes on cam and the carbs start to pour the juice in it accelerates like a scalded cat, power is significantly better, it sounds 'right' it ticks over like a dragster and under the bonnet looks great. I have no ECU, lambdas, throttle pot or air flow meter to worry about, it wont learn any bad habits and I can bin the air intake for better cooling. The only downside is that the carbs are a tad thirstier (that could be the kid with a new toy syndrome) and the solid lifters need tweaking every service (£40) I still can't get the hang of starting with a warm carb yet though
Steve, from my own experience I'd say that might not work for every engine.
Mine was a case in point, it had an absolute clean bill of health mechanically and electronically and the combined might of V8 Developments (28 years of Rover tuning) and 'The Guru' Mark could not get to the bottom of it. The only concensus seemed to be that because of the large valves the airflow might be a bit weird at low throttle openings, this in turn could cause the ECu to overcompensate resulting in it chasing it's own tail so to speak. Fitting something less sophisticated or indifferent to these subtleties might've done the trick in my case. The only curious thing is why it started to appear after a period of being fine.
Fact of the matter is, it's not a unique problem and fitting a hot cam might aggrevate the problem.
Mine was a case in point, it had an absolute clean bill of health mechanically and electronically and the combined might of V8 Developments (28 years of Rover tuning) and 'The Guru' Mark could not get to the bottom of it. The only concensus seemed to be that because of the large valves the airflow might be a bit weird at low throttle openings, this in turn could cause the ECu to overcompensate resulting in it chasing it's own tail so to speak. Fitting something less sophisticated or indifferent to these subtleties might've done the trick in my case. The only curious thing is why it started to appear after a period of being fine.
Fact of the matter is, it's not a unique problem and fitting a hot cam might aggrevate the problem.
Yes but your case is pretty rare. I've done several cam upgrades and seen the guys at Tower View/RT Racing and Mark Adams all go down this route and get superb results. So I would say carbs might be worth considering but they are not the panacea for everything and also introduce problems and issues of their own. They are mechanical and wear out and can go out of alignment. To be honest chasing a problem with an injection system is a lot easier than chasing on with a carb system (based on previous experience with various carb set ups).
I think your car was a big exception and not the rule.
I think your car was a big exception and not the rule.
I think we're both agreeing with each other albeit from opposite sides of the fence. I'm not saying carbs are a panacea to bad manners at all. What I am saying is that cars with bad manners that have been mapped could have a similar problem.
My car had the guys baffled, the carbs better than fixed it. The injection system would be the preferable choice (maybe) but maybe the old Buick throws it a curve now and then, possibly due to the huge variation in the hand worked heads. I'd like to see if changing them makes any difference.
My car is not alone in this either
My car had the guys baffled, the carbs better than fixed it. The injection system would be the preferable choice (maybe) but maybe the old Buick throws it a curve now and then, possibly due to the huge variation in the hand worked heads. I'd like to see if changing them makes any difference.
My car is not alone in this either
Yeah we are probably in violent argreement. 
To be honest your car has had a lot of mods done to it which makes it more and more unique and therefore prone or whatever the word you want to use to being a little bit difficult. I also believe that the more modified the engine gets, the less predictable the recipe can be and in some cases the more extreme the cure.
I also think that the low end smoothness is a bit of a luxury. Some engines don't like pulling away from 1000 rpm in fifth. Is that a real problem when all it takes is a gear change to solve the problem. You can't do that in a Cerbera so why should it be taken as essential in Griff or a Chimaera? If it goes like a scolded cat at higher revs, is this really worth worrying about? Labouring the engine in this way does make it more prone to pinking and predetonation.
It is not something that you can do in most other cars. Especially 4 cylinder Euroboxes?
>> Edited by shpub on Tuesday 6th January 16:39
To be honest your car has had a lot of mods done to it which makes it more and more unique and therefore prone or whatever the word you want to use to being a little bit difficult. I also believe that the more modified the engine gets, the less predictable the recipe can be and in some cases the more extreme the cure.
I also think that the low end smoothness is a bit of a luxury. Some engines don't like pulling away from 1000 rpm in fifth. Is that a real problem when all it takes is a gear change to solve the problem. You can't do that in a Cerbera so why should it be taken as essential in Griff or a Chimaera? If it goes like a scolded cat at higher revs, is this really worth worrying about? Labouring the engine in this way does make it more prone to pinking and predetonation.
It is not something that you can do in most other cars. Especially 4 cylinder Euroboxes?
>> Edited by shpub on Tuesday 6th January 16:39
I'm sorry mate but I beg to agree 
In my case the car ran fine until about a year ago. It gradually become more and more unmanagable in town (this was a bog standard car at this stage)and it was getting tappity, mileage was about 60k so I decided to go for a cam change. This didn't improve things and this is where my journey to enlightenment began, or rather didn't cos I still don't know what caused it. The problem mainly was at 30mph, you are right on the 2000prm point and you have to rev it in 2rd or chug along in 3rd most irritating.
In my case the car ran fine until about a year ago. It gradually become more and more unmanagable in town (this was a bog standard car at this stage)and it was getting tappity, mileage was about 60k so I decided to go for a cam change. This didn't improve things and this is where my journey to enlightenment began, or rather didn't cos I still don't know what caused it. The problem mainly was at 30mph, you are right on the 2000prm point and you have to rev it in 2rd or chug along in 3rd most irritating.Gassing Station | Griffith | Top of Page | What's New | My Stuff