What's everyones opinion on running a gilmer belt drive set ups on a 308? Please help

**IOUDAD** · 10-10-2012, 04:10 PM

Hey guys!
I've been told a mixture of things about gilmer belt drive kits and would like to know if anyone can help me decide weather to run one on my 308 or not!
I have finished my 500+ hp 308 install in my HZ ute and really love the look of the gimer belt drive kits and also the sound!
Alot have people have told me they are more trouble then they are worth :/ they have a habit of breaking and will just cause me drama..
Is this the case? As I want to dress the front of my motor up with the pulleys etc..
My motor is VERY responsive and I have been told this will put it under even more strain..
Any help or advice would be awesome

Thanks
Tenille

**HK1837** · 10-10-2012, 04:55 PM

I think you'll have more to worry about with a 500hp 308 in a HZ ute! What is the drieline?

**IOUDAD** · 10-10-2012, 06:47 PM

What are you referring to when you say more to worry about? It's running with a rebuilt and strengthened TH400 with a 3200rpm stall, it currently has a shortened 10bolt Salisbury diff (open wheeler) that is being replaced with a bullet proof shortened (due to mini tubbed ass end) 9" diff!

**HK1837** · 10-10-2012, 07:39 PM

I was thinking more about the chassis's ability to handle that sort of hp! :-) Reliably anyway. Plus stuff like unis, leaf springs, brakes etc!

I know little about Gilmer drives though, so can't really help on that front. Maybe look at what the carbied group C and group A cars were running, they were pulling 450hp or thereabouts. There are a few of them around still running as per original engine bays. Most of the A9X's that finished in the top 5 or so from 1979 are still kicking around, and a lot of the VC-VL Commodores are still around too. What sort of 308 is it that develops 500+ hp? I assume it is blown? Or at least stroked to near 400ci?

**Innuendo** · 10-10-2012, 07:59 PM

Hi Tenille,

The Gilmer belt pulley system will be fine if used correctly. These smaller 1" to 1 1/2" belt versions are NOT designed to make noise although can be forced to do so.
This is by overtightening and this is when they fail. The aluminum wares away due to friction. Gilmer pulley systems should NOT be confused with gear drives. If you want the noise, you should add straight cut timing gears.
If you want the billet pulleys because of look and to work as intended, don't expect noise and do not overtighten or they will eventually fail.

Brand also matters!

Regards, Smooth

**RAEME** · 10-10-2012, 09:10 PM

True that Smooth, Tenille love gilmer drive kits, as above you have to spend the cash on a quality unit. Mate of mine bought a cheaper one it's now in the bin. I have a straight cut belt on my supercharger and it screams. ( it's a bit too loud)
You need to be able to twist the belt back on itself 1/4 to 1/2 turn. I also had a Peter Jackson gear drive in my old police pursuit VL and it was superb noisy at low speeds and quiter at high rpm. I would expect you might already have a gear drive in your engine (500hp) plus you might need one.

**IOUDAD** · 10-10-2012, 09:43 PM

Originally Posted by HK1837

I was thinking more about the chassis's ability to handle that sort of hp! :-) Reliably anyway. Plus stuff like unis, leaf springs, brakes etc!

I know little about Gilmer drives though, so can't really help on that front. Maybe look at what the carbied group C and group A cars were running, they were pulling 450hp or thereabouts. There are a few of them around still running as per original engine bays. Most of the A9X's that finished in the top 5 or so from 1979 are still kicking around, and a lot of the VC-VL Commodores are still around too. What sort of 308 is it that develops 500+ hp? I assume it is blown? Or at least stroked to near 400ci?

I'll do some research into them over the next few days and work out what I should do.
The motor is a 308 crank so unstroked, and also naturally aspirated!
The motor has had some serious building to pump out this hp and was the most HP a well known Tasmanian mechanic has seen out of a naturally aspirated 308.
Spec:
Crain hi 6 ignition system
Full ARP stud kit in motor
Acel bearings
20 up on the bore
Crow push rods
HUGE Crow cam solid cam .680 tho lift
$8000 spent on porting and head work
750 Holley
Gide plates 4 push rods
Crane dual valve springs
Heads ford 4v valves
Ford roller rockers
Rockers are Yella Terra
10 to 1 completion ratio
Motor is balanced and blue printed
Standard stroke crank 308
Crank is brand new and was nitrated so are the rods
Flat top pistons forged pistons
Fel Pro head gaskets etc etc

--- Updated ---

Thanks for the helpful info Smooth!

**HK1837** · 10-10-2012, 10:53 PM

Geez it'll be lumpy! Would sound wicked though.

**L31 Sandman** · 10-10-2012, 11:53 PM

Hi Can you tell me the cam model number. I know its possible to go a little bit over 700 lift in a 308 but I have never heard of anyone putting in a cam that big!