CAMSHAFT CHOICE
Turbo Mini Forums

I am using the 274i cam with 1,5 rockers.
My thougths were: short inlet duration: the boost will make good filling.
Long exhaust duration to get rid of the "more than na" amount of gases.
Big LCA (112°) to reduce overlap (because TIP(turbine inlet pressure) is higher than boost pressure)
1,5 rockers to "compensate" for the short durations.
Engine made 141hp at 0,9bar boost on the rollers!
But interesting to hear from"the hungry lion cam " - I will give it a try for next season!

Bimmer Twinky headed and turboed A-Series:
http://www.minifreunde.at/harry/projects.htm

Turboharry...

Result!

just to knock every thing right out of the window on cam choice t3tone has just got 150 bhp at the flywheel running 10 psi with intercooler but wait for it , running a 276 kent on 1.5's.

i was bloody suprised to say the least.

just goes to show on every thing said about short or long overlaps, duration, and lift for turbo motors what they do and dont like, that this has just blown all the theory's out of the window, as a 276 has got longish overlap and lift all apparently a turbo doesnt like, and is very drivable round town apperently.

always looking for them bigger bunches of bannanas

Seems to be a lot of variation, which can only be a good thing on the quest to pick a good cam

I have not had any problems with 1,5 rockers over the years. Well, the only exception being my 970S engine with 8-port head. It would have run better with lower ratio...

Anyway, first cam I used was Stuart´s cam, the present one was Avonbar Phase 2. The engine is 1380. The engine pulls very strong from low down and RR figures verify this. The ports are conservatively cut, even if the valves are 36/31 mm, ex offset. It works as a package, change something and it may produce totally different results.

AlexF

use it on the mpi with the m45 s/charger no probs 132 bhp(5200 rpm) on the rollers but torque only 135 ft lbs @3900 - it is only a 1275 cc - also on 1.5 rr , tried standards didn't seem to make much difference drivabillity or power , which probably indicates something else is a limiting factor

I have been doing some thinking about my M45 build and decided on using the Avonbar Phase 2. But........I haven't bought it yet and so was thinking about the difference between supercharger and turbo cams. I haven't seen one advertised, but I am aware of one in Oz. Vizard and a couple of other turbo books I have read go on about the importance of opening the exhaust valve early. I assume that the 2 cam specs for an identical engine would just vary on this point. (assuming that you keep the lobe centre angles the same). I'm going to find out for sure before I waste my money. Allthough a P2 looks good at the moment for what I want......Do you use them on standard rockers? I have heard you do.......anyone?

stu (pile of parts roughly the same size)

Bugger off, I'm getting there.

Giallofly, the problem in Austria is we have only a few, very expensive RR. If you go there these guys often see a SU carb for the first time!!
So you can imagine how I trust them.
I want to deliver some graphs when our own RR is running! (rocker changes can be done very quickly, but not if you have to pay 55 pounds/hour and/or I have to travel 100miles to the RR)

Bimmer Twinky headed and turboed A-Series:
http://www.minifreunde.at/harry/projects.htm

Turboharry,

I think you you have misunderstood "result", it is a complimenet meaning "good result"

Personally i am not phased by bits of paper with figures on, just overall performance of the car when complete.

Sounds to be a very sorted engine package.

Jon.

Hi Giallofly,
yes I misunderstood then! Thanks for the compliment. The problem is you hear a lot of different good working engine combos, but everybody has a different sight what a good engine is. You never know until you try yourself. The phase 2 cam will have to be tried by me next season, because it seems that a lot of people swear on it.
Harry

Bimmer Twinky headed and turboed A-Series:
http://www.minifreunde.at/harry/projects.htm

i have the kent turbo not sure what one as i got no papers with it but it is supposed to be 649(exhaust) and 544 (Inlet) plus 1.5's non roller goes really good road and strip but i have been thinking of changing but do not know what to get.

179hp on 12psi 1293cc of pure A series
14.0et @101 mph

well guys after much Deliberation by all, THANKS. it would be nice for every one to put there engine specs (ie) cam,compression,boost ,power, outputs, etc on this thread. it will enable ALL to juggle the configurations and make a better choices for future engine rebuilds.
BENROSS:

That is a good idea.

Why not start a thread in a different category such as Knowledge Sharing?

I could post my intended spec but not much use really......

THANKS TOM i have just done so.
we can all, NEVER have enough
knowledge. Especially on the blown "A" Series engine.

BENROSS

Good idea...

My spec is very long, but in a word doc so i'll ctrl C & ctrl V it once i've found it!

To all,

I've got a Kent Cam in a box here that I've had since about 97/98/99 and it has KCRTM written on the box. Anyone know the specs of this cam as in timing and lift?

I've emailed Kent but no reply yet...

Cheers

Daniel

First 5-port EFI turbo in the world (built 1997, running in 1998)

Apparently this KCRTM is probably a KC500. I will be throwing this one in as I've been told its the best race turbo cam and since I don't use my car for street use anymore I think that will be ok.

Daniel

First 5-port EFI turbo in the world (built 1997, running in 1998)

I was reading this alng with all the other threads a search for phase2 (& pahse 2) threw up but can not find the lift figures .... anybody know?

Every day is a school day ...........

How fast and how expensive ...... the same question...

I found the data on here recently, but cannot found it now.

Anyway the attached may help.

Attachments:

6.21kb

Saul Bellow - "A great deal of intelligence can be invested in ignorance when the need for illusion is deep."
Stephen Hawking - "The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge."

286 at high comp. ratio