Hey all,

I'm looking at getting some stage 1 cam's very shortly and i need to know what spec's would be best suited to lpg.

Secondly where do i get them from? because from what i've read it's best to avoid RPW and Tighe cam's.

thanks in advance

Isnt Mike thinking of upgrading his to a more wild set? Maybe his second hand ones? Also i saw Alan J post this:


Yes the Ralliart/380 cam is very very mild. The old "6" cam in the 163kw 3.5 ltr was 171 deg duration @ 0.050" and 9.05mm valve lift, the Ralliart/380 is 181 deg duration @ 0.050" and 9.8 mm valve lift, the cams Graham has just made overseas and returned to Aust with are 196 deg duration @ 0.050" and 10.9 mm valve lift. The LS1 is 206 deg duration @ 0.050" and 11.9 mm valve lift.

Cheers,
Alan

mikes going bigger? hmmm interesting
i was thinking of getting either 262 or 272 degree duration cams

Hey all,

I'm looking at getting some stage 1 cam's very shortly and i need to know what spec's would be best suited to lpg.

Secondly where do i get them from? because from what i've read it's best to avoid RPW and Tighe cam's.

thanks in advance

There does not appear to be any cams but those from Tighe at present. Graham Bell researched extensively but couldn't find anyone doing cams for the Magna apart from Dean Tighe. After driving all the way to Qld (couldn't get any sense via email) to personally meet with Dean Graham realised Dean knew nothing about cam design and grinding so Graham decided to go to the expense of doing a Magna/380 specific cam himself even though this was going to be expensive, and may not be successful.

There are some doing Magna cams based on using Lancer EVO masters. The first problem with those is they are very low valve lift so you need a lot more duration to get decent top end power, and then you lose bottom end power. Magnas are already sluggish at lower rpm due to inlet ports being too big and cams being retarded. The second problem is, because these people don't know how to design a cam (they just copy other peoples EVO cams) that the cam for the front bank is reversed. This places the opening ramp on the closing side and the closing ramp on the opening side. For a track engine this isn't a big issue but for a road engine the lifters can rattle badly and the valve seats are pounded and wear more rapidly.

Graham has gone to the trouble and expense of making 2 pairs of master cams. One for the rear bank, and one for the front bank, so that all the lobe flanks and ramps are on the correct sides of the cam lobes.

The next problem was that he couldn't buy blank billets except form Tighe. Graham didn't trust Tighe to heat treat correctly and the lobes were finished too narrow across the shoulders for what Graham needed anyway. So a couple of weeks back he flew overseas to a company he has used for NASCAR cams. They have a proprietary plasma process to build up the lobes of chill cast cams to endure 9,600rpm for 2-3 hrs in 355cu in V8s. (Some prefer steel cams with hardfaced welded lobes but others use cast cams as they have superior harmonic/resonance damping characteristics). They have used the process previously with roller cams (NASCAR are flat tappet) and are confident that the process will work on the Magna.

Graham is back with his cams last week. The last I heard from him is that he has them fitted to a dummy 3.5 6G74 engine to check valve to piston clearances, and they are OK. He is yet to do a dummy check on his 3.8 6G75. He got sidetracked doing a couple of more tweaks to the inlet ports on his test heads and thinks he will have the flow numbers in a few days. Once he finalises the head work he will fit the cams and heads and begin performance and endurance testing. If all works out without any issues there could be good cams available before years end. Hopefully!!!

Cheers,
Alan

At last a scientific, engineering approach to the problem.

Please keep us all in the loop.
Maybe Xmas pressy time.
Gerry

hi alan, how do you tell if the cams are "6" or another version. the reason i ask is my car was fitted with a second hand engine 30,000 kms before i got it and i have no idea what year/ model the engine came from. i am interested to see if i have say one of the 163kW engines or the lower power ones. cheers.

With these cams, can we not just used a std set and get someone to re-grind these if they know what they are doing?

With these cams, can we not just used a std set and get someone to re-grind these if they know what they are doing?

Yeh but who would you trust to do it? Thats the main reason i got Ralliart cams, no way i was gonna pay what RPW want and only heard horror stories bout Tighe

Alan, are they made by Andrews?

Yeh but who would you trust to do it? Thats the main reason i got Ralliart cams, no way i was gonna pay what RPW want and only heard horror stories bout Tighe

RPW get their cams from Tighe

hi alan, how do you tell if the cams are "6" or another version. the reason i ask is my car was fitted with a second hand engine 30,000 kms before i got it and i have no idea what year/ model the engine came from. i am interested to see if i have say one of the 163kW engines or the lower power ones. cheers.

AFAIK same engine different muffler.

AFAIK same engine different muffler.

Some of the older donks, ie up to s2 TJ, had a different cam profile and tune AFAIK. The S1 TJ sports/VR-X got better cams, muffler and tune than stock, and the S2 took the cams and tune on across the whole 6G74 range. If that makes any sense at all.

EDIT: better add i'm talking about older 6G74 engines. Too many draughts...

Alan thankyou very much for your detailed reply,would you say it'll be worthwhile waiting the 6 months or so for these or just have some ralliart cam's installed now...

I have fitted a set of these Tighe and to be honest was little impressed with the finish such as the champher to allow the cams to be fed into the heads were all but not there making fitting very hard

The lift was higher post fitting thus the lash adjusters had to bleed back a little but this is exactly what I expected.

The owner seems happy with them as well in so far as gains etc goes

Would be good if someone who actually does know what they are doing would start to make cams, this Graham seems to know his stuff so would be good to perhaps see him come on as a sponsor and support the club while the members can also support him

RPW get their cams from Tighe

Yeh i know, what i meant is i refuse to buy stuff from RPW period. And i have heard about people buying cams direct from Tighe and still getting problems, so i dont trust either.

Some of the older donks, ie up to s2 TJ, had a different cam profile and tune AFAIK. The S1 TJ sports/VR-X got better cams, muffler and tune than stock, and the S2 took the cams and tune on across the whole 6G74 range. If that makes any sense at all.

EDIT: better add i'm talking about older 6G74 engines. Too many draughts...

how would i tell whether i have a older or newerS2 engine?? my cars a Diamante SEI, (KE Verada) aussie made but engine was swapped out.

I have also used tighe cams and i have had no problems with them, but once the manual eventually gets installed i will be looking at upgrading, so if Graham goes ahead with it, i to will also be looking at supporting his product.

Alan thankyou very much for your detailed reply,would you say it'll be worthwhile waiting the 6 months or so for these or just have some ralliart cam's installed now...

To get the most outta these cams you should look at bumping up the compression a little and maybe a mild port job. You most likely will need to reflash your ecu.
I'm looking at a simmilar thing as you and thinking of installing lpg. So i'm interseted in replies. I'm gonna sqeeze Jason for some opinions soon.

Yeh i know, what i meant is i refuse to buy stuff from RPW period. And i have heard about people buying cams direct from Tighe and still getting problems, so i dont trust either.

Ill point you in the right direction when I get back to Perth, I know of a few mechs I would trust with cam grinds. You have heard the one in my 2.6 and thats a regrind, cant buy lumpy stuff off the shelf for my engine.

Ill point you in the right direction when I get back to Perth, I know of a few mechs I would trust with cam grinds. You have heard the one in my 2.6 and thats a regrind, cant buy lumpy stuff off the shelf for my engine.

I only ever listen to the wastgate on yours mate lol and after the probs i have had with mine aint no one getting near them lol

lol... aint no waste gate on mine.... just 3" turbo back with a gutted cat = pure turbo scream...but you give me ideas

back on topic, no worries, other wise I would recommend the guys that built my engine.

To get the most outta these cams you should look at bumping up the compression a little and maybe a mild port job. You most likely will need to reflash your ecu.
I'm looking at a simmilar thing as you and thinking of installing lpg. So i'm interseted in replies. I'm gonna sqeeze Jason for some opinions soon.

i'll only be opening the engine if i'm building it for forced induction otherwise the cost vs outcome dosn't seem worthwhile to me for an atmo build.

reflashed ECU is organised

Just as a bolt in cam, i'd be intersted in the Ralliarts benefits.

Although, some folks tend to think a cam is a magic bullet, they must work in harmony with other mods. ie compression, heads, exhaust for eg.

EDIT, I've been on the cam merry go round with my Harley. There are some decent bolt in cams, but to maximise gains you gotta do the above.

noob question here but what are regrinds?
are they stock cams remade to whatever you want?
is this a better option or should you buy new ones?

Yeah pretty much dude. its literally a re-grind... lol... kinda self explanitory

New Vs Regrind, has both its ups and downs... up side is cost of a re-grind is cheaper than a set of performance cams from a shop

hi alan, how do you tell if the cams are "6" or another version. the reason i ask is my car was fitted with a second hand engine 30,000 kms before i got it and i have no idea what year/ model the engine came from. i am interested to see if i have say one of the 163kW engines or the lower power ones. cheers.

Sorry I don't know. I think there is a number on the cam. I've sent Graham an email to find out.



Cheers,
Alan

Yeah pretty much dude. its literally a re-grind... lol... kinda self explanitory

New Vs Regrind, has both its ups and downs... up side is cost of a re-grind is cheaper than a set of performance cams from a shop

can't regrind a 3.5lt cam, there's not enough material on the lobe, that's why for 3.5lt engines they have to buy either ralliart or aftermarket...

can't regrind a 3.5lt cam, there's not enough material on the lobe, that's why for 3.5lt engines they have to buy either ralliart or aftermarket...

Wrong. You CAN get a 3.5L cam reground BUT the lobes must be built up via "hard" welding and then ground to the profile that is wanted.

TZABOY has reground/reprofiled cams in his car

Basically any cam can be reground. How successful/durable it will be is another matter. Most flat lifter cams can be reground without much trouble, especially those with bucket tappets. Roller cams can be a problem as the surface stresses are more concentrated and regrinding reduces the thickness of hardened heat treated material.

The other problem is if the valve gear isn't adjustable. With reduced base circle dia you have to be able to take up the slack. Lots of modern engines do not have adjuster screws. If they are bucket tappet engines then thicker adjusting shims are fitted but with non-adjustable hydraulic lifters you have to either lower the valve train, fit lash caps or use longer valve stems.

Regrinding does not usually reduce lift and duration. Lift is the lobe height minus the base circle diameter. If the lobe height is maintained and the base circle dia is reduced then the lift increases.

Low rev roller cams as used in big diesels can be welded/hardfaced but it's generally not successful in high rpm engines as the welding tends to crack or flake from the cast iron core. With flat tappets welding works well and is often used in high stress race cams to toughen the lobes.

Cheers,
Alan

hi alan, how do you tell if the cams are "6" or another version. the reason i ask is my car was fitted with a second hand engine 30,000 kms before i got it and i have no idea what year/ model the engine came from. i am interested to see if i have say one of the 163kW engines or the lower power ones. cheers.

Graham has got back to me and said that you have to look at the end of the cam/s at the gearbox end. The part number is stamped there followed by a number. The later 155/163kW cam has a 6. He also bought a donkey engine that he was told was from a 3.5 TH. It has 4 on the cams but he can't find their specs but remembers that they were less duration and lift than the 6 cams. His Ralliart cams have 7 on them.

Cheers,
Alan

cheers so i presume you mean on the end, under rocker cover? or directly on end under the cover plate? thanks alot!!

cheers so i presume you mean on the end, under rocker cover? or directly on end under the cover plate? thanks alot!!

Oh sorry, not under the rocker cover, just pull off the end plate.

Cheers,
Alan

Graham has got back to me and said that you have to look at the end of the cam/s at the gearbox end. The part number is stamped there followed by a number. The later 155/163kW cam has a 6. He also bought a donkey engine that he was told was from a 3.5 TH. It has 4 on the cams but he can't find their specs but remembers that they were less duration and lift than the 6 cams. His Ralliart cams have 7 on them.

Cheers,
Alan


The Number "4" cams have the same total duration (248 degrees) as the number "6" cams (the TJ 6 cams open the inlets and exhausts earlier (about 4 degrees) but also close them earlier (about 4 degrees) than the number "4" TH cams). The main difference between the TJ "6" and TH "4" is the valve timing opening and closing degrees and the valve overlap.

Valve overlap is also 11 degrees (TH 19 Vs TJ 30) more on the TJ number "6" cams than the number "4"

Snip....// His Ralliart cams have 7 on them.

Cheers,
Alan
I can confirm that the Ralliart cams I picked up on the weekend also have "7" on them following the part number.

He also bought a donkey engine that he was told was from a 3.5 TH. It has 4 on the cams but he can't find their specs but remembers that they were less duration and lift than the 6 cams.

Graham has just found the "4" cam spec notes and sent them to me.

"4"

Duration @ 0.075" valve lift - inlet = 166 deg
ex = 167 deg

Duration @ 0.300" valve lift - inlet = 59 deg
ex = 44 deg

Valve lift - inlet = 8.82mm
ex = 8.15mm

"6"

Duration @ 0.075" valve lift - inlet = 174 deg + 5% more than "4" cam
ex = 177 deg + 6% more than "4" cam

Duration @ 0.300" valve lift - inlet = 71 deg + 17% more than "4" cam
ex = 49 deg + 11% more than "4" cam

Valve lift - inlet = 9.05mm + 2.5% more than "4" cam
ex = 8.46mm + 4% more than "4" cam

Cheers,
Alan

Just to let people on hear know that the new Ralliart cams from mitsu (eg. front and back bank) have diffrent part numbers but they are all the same.... because someone from mitsu has marked them front and back but they are all front cams.
And they said that they are not going to make more Back ones to fix the up the f...up.:nuts:

Back to looking around for me:eek2: