odd cam combo?

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Tony Z
Posts: 1205
Joined: Wed Aug 30, 2000 2:01 am
Location: Cape Town, South Africa

odd cam combo?

Post by Tony Z » Sat Nov 18, 2017 12:28 pm

I've been asked to rebuild a 2L bus engine and the owner wants a little more "get up and go" but using as many stock parts as possible to keep the costs down.
Our local cam grinders dont have any T4 cam profiles but only T1 profiles.
I did think of one of these two options:
1) regrind exhaust lobes to Engle 100 and leave inlets stock
2) regrind all lobes to Engle 100
I also thought about asking them to open the LCA a little to bring the overlap down (maybe 110deg).

anyone have thoughts, opinions or experience in something similar?

wreck
Posts: 150
Joined: Thu Aug 14, 2014 2:07 am
Location: Brisbane Australia

Re: odd cam combo?

Post by wreck » Sat Nov 18, 2017 5:48 pm

I've a GM hydraulic grind from a 70's 6 cylinder Aussie muscle car in my 102x71 engine that works well. you would have had them in SA maybe under a different name, Holden XU1 Torana . All the grinds a friend uses for the engines he builds are local Aussie grinds meant for either 6's or V8's . you just lose a bit because most are meant for 1.5 to 1 rockers . See if the local cam grinders have a selection of grinds for other engines and see if there is something close to what you want .
No matter where you go , there you are !

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Tony Z
Posts: 1205
Joined: Wed Aug 30, 2000 2:01 am
Location: Cape Town, South Africa

Re: odd cam combo?

Post by Tony Z » Sun Nov 19, 2017 10:30 am

thats not a bad suggestion. One more thing to look into....
Thanks

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raygreenwood
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Joined: Wed Jan 22, 2003 3:01 am

Re: odd cam combo?

Post by raygreenwood » Sat Nov 25, 2017 11:43 am

This is type 4 2L engine?.....dont play around with odd grinds and type 1 grinds. In fact.....with type 4 and its lifter contact pattern which is totally different than type 1....you are really rolling the dice playing with regrinding at all. These are case hardened only. Grinding them...eapecially to totally reshape the lobe removes some or all of the hardening layer.

The type 4 cams already have HUGE issues with oil quality and lifter to lobe hardness matching.....the results of which can bd catastrophic. Its common.
Do not cut corners or reuse parts in the type 4 camshaft department. There are excellent grinds and quality of camshaft out there.

You can easily reuse every single original part that specs out in a type 4.....except the camshaft and lifters. It just does not pay. Buy a new cam.
Ray

wreck
Posts: 150
Joined: Thu Aug 14, 2014 2:07 am
Location: Brisbane Australia

Re: odd cam combo?

Post by wreck » Sat Nov 25, 2017 7:14 pm

Ray maybe in Australia we get away with it because of the big selection of oils for flat tappet engines . I've a re ground cam in my 2.3 that is 15 years old with 100,000 km on it , my professional engine builder friend has only used re ground cams in all his engines for the last 30 years . In that time he's had only two type 4's with cam/lifter issues and that was caused by soft lifters not the cams .
He prefers to use hydraulic because he hates any sort of rattle and lot of people comment how quiet his engines are , There are very few performance type 4 hydraulic cams on the market but heaps of hydraulic grinds for other engines so he talks to the cam people about what they recommend for what the custom wants in the engine and goes with that .
On a funny note , he rebuilt his son's 100cc dirt bike and wanted a higher lift cam . the cam bloke wouldn't tell him what it was till he got feed back on how it went , the result was a bike with a lot more poke and a ford RS 2000 cam profile !
No matter where you go , there you are !

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