TB 42 Cam

[stevejl]

Hi fellas

I turboed my tb42 about 18 month ago and it was going good power wise but was useing alot of oil , as far as i know the engine was standard before I turboed it . Because it was useing oil I rebiult it and got it balanced and the cam re grownd. The cam was grownd by a so called turbo/cam expert and the rebiult engine does not got as good as the three parts f#*ked engine.
My question is is this the best cam for my 4by new engine specs are

Engine TB42 Bored .050

Cam IN EX
Running clearance .016" .019"
Lift @ Lobe 282" 282"
Advertised Timing Opens Closes
Exhaust 56º 27º
Inlet 25º 67º
.050" Valve Timing IN EX
Duration 213º 208º
Inlet Lobe lift @ TDC on the overlap .042"

Ignition
Regrafed dizzy with
pertronics flame thrower 2 electronic ignition
7amp ICE ignition module
ICE lightning race series coil
ice 9mm pro 100 series leads

Turbo Compressor Turbine
oil/water cooled AR .70 AR 68

waste gate 38mm external

Gas system
Impco 225 mixer
Impco E type converter with balance tube

inter cooler
1000HP water/air
Any help would be good if I can change cam fuel system or some thing to make it go better would be great Thanks Steve

[create]

Steve,
I wouldnt say that I am an expert on this one but I will throw in my comments.
I think your impco 225 is too small. I dont think it will have enough flow for a turbo engine. Are you running straight gas?

Is your regraphed dizzy still running vacuum advance? I got rid of mine and ran about 20 degrees static advance and that helped heaps.

I had a cam regrind done for my engine and I am really happy with it. The specs are-
inlet open 26 - inlet close 62 - exh open 72 - exh close 16 - duration 268/268
I'm running a TB45 engine straight gas with an impco 425 and it runs out of puff at about 5000rpm. I've got bags of torque really happy with it.

I think your spot on with your ignition, everything should be fine there.

Maybe put it on a dyno?

Phil

[hokey]

quite interested in this. my mate is rebuildind a tb42 for turbo atm and wants to get a cam done.

create: all the tuners i've spoke to say 225 is better size than 425. people make 200kwatw with a 225. just what i've been told

[big lux]

it took me awhile to find this when i was doin a tb42 turbo, should give a abit of an idea of what grinds do what. was about $800 when i enquired about them. http://www.crower.com/misc/m_cat.shtml" onclick="window.open(this.href);return false;

[create]

quite interested in this. my mate is rebuildind a tb42 for turbo atm and wants to get a cam done.

create: all the tuners i've spoke to say 225 is better size than 425. people make 200kwatw with a 225. just what i've been told

I'm no expert when it comes to turbo engines but from what I have seen a 225 is only good for an absolute max of 200rwkw. To get some head room I bought the 425 just in case I go turbo.
impco 225 = 329cfm
impco 425 = 460cfm

[cooki_monsta]

quite interested in this. my mate is rebuildind a tb42 for turbo atm and wants to get a cam done.

create: all the tuners i've spoke to say 225 is better size than 425. people make 200kwatw with a 225. just what i've been told

I'm no expert when it comes to turbo engines but from what I have seen a 225 is only good for an absolute max of 200rwkw. To get some head room I bought the 425 just in case I go turbo.
impco 225 = 329cfm
impco 425 = 460cfm

i have used both. the 225 when blown through is more then adequate for mid hp turbo gq's. i had a 425, but i had the common problem of rich idles, and backfiring. This turned my 425 into a bag of die cast steel inside its pressure hat.

im still running the 225, i picked up a small ammount of low down torque with it compared to the 425, and i also run the aussie b2 converter by lg systems.

my pick of the 2 is a clean air 225!

[stevejl]

hi
Thanks for your input. I have a two stage vacume advance sowhen it comes on boost it is ment to take out some timming. I have thought of making a new intake with a 425 on a 4 barrel carby butterfly setup. Mabye I should just get it dynoed so I don't keep chasing my tail, I know the engine has more to offer as it starts to go and then justs hits a wall. Will let you know when I get it going good. Thanks again Steve

[turbmav]

Mate check that cam duration at 50"it's all wrong on a turbo. Has less duration on the exhaust than inlet, thats crap, plus not any bigger than standard.

[stevejl]

Hi turbmav
what cam would you say. I have to pull the engine out any way so while it is out I will change the cam. can I buy one of the shelf or do I have to get one regrowned I have a standard cam handy if I have to grind one. Thanks for the help