piper 255 cam

[plasticpig72]

i wondered if someone has tried a Piper 255 cam (high torque i think) in their car.
I am finding the Piper 285 fitted at the moment very tiring for pleasure drives. Keeping the revs above 2200 rpm on Sunday drives a pain in the butt. I don't intend to do circuit driving and i would like something more agreable to drive with swmbo as passenger.
my car is a 1600m

[Dollyman1850]

The caravan cam !!

[Slow M]

Believe I had a 285 in my 2500, with a fair bit of head work, electronic ignition, high ratio roller rockers, tubular exhaust, and a throat per cylinder. I enjoyed that engine. Wouldn't have wanted anything milder. Memory said there was a distributor recurve kit.

Best,
B.

[plasticpig72]

the 285 splutters and just about starts to operate from 2200rpm.
Looking at pipers own cam data the 285 operates from 2000rpm to 6000rpm and is good for track days.
My Lotus Elan Sprint pulls smoothly from 1000rpm.
My 1600M splutters untill it reaches 2200rpm and then just starts to think about delivering the goods which is no good for me.
My boy racer days are in the past and i don't drive round the Goodwood Track anymore.
So has someone fitted a Piper 255 to tow a caravan behind their TVR or for retired peoples Sunday drive to the pub to talk about the good old days

[timelord]

I had a 285 cam in my 1600M in the past and can understand how you feel driving your car "normally", mine had a close-ratio gearbox to make matters worse! The last engine rebuild I changed to a Kent 234 cam, what a transformation! Still hotter than the standard GT cam but running on twin side draught Webers the car is more tractable from low revs but howls once over about 3500rpm to over 6000rpm. On the rollers my car makes 100hp at the wheels at 5750rpm but still produces 85hp at 2800rpm, and the close ratio box has gone too, first gear was too high for slow traffic saving lots of clutch slipping! Geoff

[tomtrout]

Plenty of low down grunt running the Kent 234. I don't know when it runs out of puff because I get scared long before it stops pulling!

[Dollyman1850]

plasticpig72 said:

the 285 splutters and just about starts to operate from 2200rpm.
Looking at pipers own cam data the 285 operates from 2000rpm to 6000rpm and is good for track days.
My Lotus Elan Sprint pulls smoothly from 1000rpm.
My 1600M splutters untill it reaches 2200rpm and then just starts to think about delivering the goods which is no good for me.
My boy racer days are in the past and i don't drive round the Goodwood Track anymore.
So has someone fitted a Piper 255 to tow a caravan behind their TVR or for retired peoples Sunday drive to the pub to talk about the good old days

Back in their day they were always called the Caravan cams. Its a bit better than a std GT cam but peak power is delivered a bit further down the range. They deliver much more torque and give a nice road car plenty of low down grunt. You have a light car so it depends what you want to do and what diff ratio and gearbox ratios you want. Slightly higher back end ratio and a 5 speed would make for a lovely road car with the old Caravan cam. if you want top end power and the rest of your engine is built to rev with 40's etc than you are undoing previous mods. The cam is an improvement on an otherwise standard engine.

N.

[plasticpig72]

well that settles it Piper 255 or if price is better Kent 234.
Many thanks chaps

[prideaux]

I am running a 245 on twin 40s lightened and balanced and ported with a 5 speed box rather nice smooth road car really all through the rev range and can be driven either as a lazy sunday driver style or if you want to drive using the full RPM in all gears she performs beautifully I cant give you more info than that as Alan who re built the car was a race car engineer and he built it as he wanted it to drive his plan I believe in talking to him was a Road/sprint car whatever the plan it does drive very nice
Andrew

[plasticpig72]

what was the camshaft that TVR used in the 1600M was it the standard Cortina GT cam or Escort Mexico
Does someone know!!!!
many thanks in advance
Alan

[timelord]

Engine was Capri GT, because of the rear sump, which is the same as a Mexico. I believe a GT cam was the same spec throughout the entire range, Geoff

[plasticpig72]

i have just removed the camshaft from the spare engine block which came with my 1600M. It is supposed to be the original one from when the car was made. The markings on the camshaft are IM-6250-DA and in another place RB4 and ford. I have measured the profiles heal to toe and they are just under 33mm (32.85mm to 32.98mm). Is this the ref n° for GT Capri cams
many thanks if someone can help to identify the camshaft please

Edited by plasticpig72 on Monday 27th October 10:40

[plasticpig72]

the engine runs very Well and clean but under 2200rpm it is very flat(crap)piper 285.
imho it is just a case of changing the cam for a normal relaxed road cam such as Piper 255 or Kent Cams X/flow "GT" CAMOHVGT from Burton. The engine is very solid and for sure it's not necessary to change the complet engine but only the cam.
With a milder cam it will also pass the polution contrôle for the mot much easier.

[bluezeeland]

plasticpig72 said:

and for sure it's not necessary to change the complet engine but only the cam ?

Hi Alan,

No, It won't, but the replacement cam should be 'adapted' to the present heads (don't remember what you got...).
Timing, carb and induction should be checked/reset, afterwards

Frank

Edited by bluezeeland on Tuesday 28th October 19:18

[plasticpig72]

hi Frank,
you are 100% right.
I think i will put a milder cam maybe Kent CAMOHVGT from Burton. The head has been flowed a little but not too radical about stage 1+ a little. Carbs twin 40 dcoe's.Duplex timing chain balanced and lightened. Dizzy Lucas same as Lotus Elan/ Cooper S no vacuum advance.
With the Piper 285 keeping it above 2200rpm for me is not relaxed driving.
If someone wants to buy it for track days and boy racing it's on the market for
12000 €uros

[bluezeeland]

Boy racing ? Thats me out then !

If the forum agrees on the 234, why not give Chris at Burtons a call, just to confirm, and order up the cam ? You are able to do the work yourselves, saving the labour, so its not massively expensive !

[Dollyman1850]

bluezeeland said:

Boy racing ? Thats me out then !

If the forum agrees on the 234, why not give Chris at Burtons a call, just to confirm, and order up the cam ? You are able to do the work yourselves, saving the labour, so its not massively expensive !

I like the 224 for a mild engine. I'm not an expert though!! I also moved away from crossflows a good few yeas ago. Lovely first engine to build though. Very simple and very rewarding to put together. I used to play with them a lot the first time around in escorts and fiestas.
If you are running 40's a 234 is ok for max power but as ever if you push up the rev range for power you will loose out down below. The 224 is only about 10hp down on the 234 but delivers more tractability lower in the rev range especially on a std twin choke carb..
N.

Sorry forgot to add..As a non expert who has only built a few of these engines I would advise that the deck height is critical. Blocks of kent engines often get skimmed to raise compression (flat top cylinder head) You will ALWAYS need to dry build an engine with a 224 cam to make sure the deck height won't cause piston valve contact. you will Definitely need pocketed valves with an upped compression and 234 cam. if you are down speccing your engine then I would assume you have the pocketed pistons already to allow for the higher lift of the cam you are taking out. Other thing is that you change cam and followers as a set. Also buy yourself some Graphogen to build up the engine and run a zinc additive in the oil on fire up.

This topic sort of come up a few years ago…..

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

Edited by Dollyman1850 on Tuesday 28th October 21:32

[tomtrout]

All good advice Neil but I guess as Alan is looking for a milder camshaft in his existing engine he will not have to worry about valves fouling on the piston crowns. I guess that as Alan has already removed a cam from a spare engine he will know that the job has to be carried out with the engine upside down (unless there is a magic trick to keep the followers up while withdrawing the shaft that I don't know about? Thought I would mention it just in case others are contemplating a change of cam in their crossflow.

So although not expensive, still a relatively big job.

[griff 200]

If you don't want to turn the engine over small magnets from a toy shop or e bay glued to strings works for me !!

[tomtrout]

Excellent tip but you can't change the followers with string and magnets!
Actually I guess you can if you drop the sump and push the followers up from below. Almost easier to take the engine out and flip it over!

Edited by tomtrout on Wednesday 29th October 11:26