aftermarket belt drive?

[3.4Z24]

has anyone found an aftermarket source to use a gilmer or HTD belt on the cam drive? if not, i'm going to have some custom pulleys made and maybe offer a kit to do this myself.

[Anonymous]

Why would you need one?

[grandprix34]

wats the HTD belt about? I had a crazy idea too of chaning the cam gearing frmo belt to chain since you can machine custome cams for a chain drive...it was only an idea

[jmgtp]

I think modding the physical features of the timing belt system in any way is asking for reliability issues. The stock setup isnt bad, just needs to be maintained, although I do feel 60k is too much for it. I think 40k is more realistic... then again I had the belt tensioner let go after 30k, everything else was ok though. I guess mileage isnt the best indicator, seeing how we all drive differently, I bet a car that is abused more and sees high rpm more often will wear the components of the belt system faster.

Anyways what are those belts you mentioned? Are they just higher performance belts? less friction or something?

[3.4Z24]

many aftermarket dry sump oil pump drives and GMC roots blower drives use gilmer and HTD belts. they have rounded or square teeth instead of hexoganal(stock) and you can get them with kevlar in the belts. i'm going to use the round teeth-they're more suited to high rpm use.

i'm not changing the tensioner system or pulley diameters. i just want a higher performance belt drive that doesn't shred itself.

2300 ford racing four cylinders convert to round tooth belt cam drives and are very reliable to close to 10k RPM and see the racing equivalent to 200k street miles before thier systems need maintenance. i don't think reliability is going to be an issue there.

i'm going to go ahead and send my pulleys off and do a have some prototypes made, then. i'll post on cost estimates when it's finished and keep updates on milage and wear.

one of the reasons i'm doing this is to keep teardowns to a minimum. i just picked up a '94 lumina z34, so in car belt maintenence isn't an issue there. but pulling the 3.4 out of my '95 cav everytime i need to change the whole belt drive system doesn't appeal to me.

also, i've heard of the alluminum pulleys wearing out. having them hard anodized seems to solve this and it's not an expensive process.

[Anonymous]

Whats a Cavalier Z34?

[RacerX11]

Whats a Cavalier Z34?

I'm guessing it's a '95 Cavalier with a 3.4 DOHC swap.

Marty

[RacerX11]

wats the HTD belt about? I had a crazy idea too of chaning the cam gearing frmo belt to chain since you can machine custome cams for a chain drive...it was only an idea

The cam drive type has nothing to do with machining custom cams. There aren't any blanks available, so your two options are regrinds of stock cams, or custom billet cams (lotsa $$). It will be the same cost even if you have a chain drive instead of a belt.

Marty

[bwawuz02]

i had the idea of changing it over to chain drive for a high performance (distant future) rebuild. i think all you would need to do is have a place like where michael has the pulleys made machine them out of solid chunks. stock cams, stock lockrings, smaller to fit chain: drive pulley, all 4 cam pulleys, idlers, and tensioner. the only hard part is figuring out exactly what size to make all the pulleys. get some titanium valve springs and beefier bottom end and you'll be revving to 9k+ in no time. anyone see why this wouldn't work? besides the fact that one might explode a lifter, but there is a lot of surface contact with the DOHC. and you'll prolly need a new puter.

[BowtieKid79]

Belts are better for high rpm use... they have MUCH less mass and less friction. i would not use a chain. It is not as simple as you make it sound... you have to have a way to oil it effectively and you also have to have chain guides to keep them from slapping around since they dont run under a lot of tension.

[bwawuz02]

well i doubt anyone will be exceeding 9k rpms with the stock belt. well at least not for very long intervals. i got changing my belt down to 4 hours on the 2nd attempt, it's not really that bad.

[brian89gp]

you have to figure out how to oil the chain.

[3.4Z24]

it's not a cav z34 yet. i'll post the engine build up here, then post the swap on the j-body.org site. should be a fun little screamer. hopefully everything will be ready to swap this spring.

[Anonymous]

Ohh... you're the guy that's been posting in the 3rd gen forum over there about it huh? I saw that thread when keeping up with the 3400 => 3rd gen thread.

[3.4Z24]

yea, that's me. i've been a big fan of the 3.4 TDC for years now. always wanted to do something funky with one because of it's great potential, and now i've got a worthy project for one.

i really like that the 3.4 is going to almost be a bolt-in.