johndregg

Active Member

• Sep 4, 2014

• #1

My V8 3.5 recently crossed 100k miles, she's running well on LPG mostly through two SU carbs, a very old set up. She also is fitted with a nice exhaust system and headers, I'm getting around 320 miles to a 90 litre fill up too. This improvement of about 60miles is down to running advanced timing and having replaced all the leads, plugs, coil etc (can't emphasise enough how important the ignition is on LPG)
I keep reading on here that at 100k the cam in a RV8 should be changed, the timing chain will be slack etc. Now, i have good compression in all 8 cylinders and under the rocker covers is as clean as a whistle, looks like new under there. Should i be changing the cam? And if so, what type? i would like a bit more torque, but maybe a standard overhaul will give me enough? Or i've also read that a 3.9 cam gives a bit extra?
What do you lot recommend? I mainly drive the car on the road but do do a bit of tame laning too.

 

zen

Well-Known Member

Events Planner

• Sep 4, 2014

• #2

kent h180 or 200, with new chain.sprockets and lifters.

 

Locky1978

Active Member

• Sep 6, 2014

• #3

I'm about to do mine and I'm gonna go with the 3.9 cam. But I will be using duplex timing kit.
I'm led to believe the 3.9 cam is the same as the standard 3.5 cam but has 2 degrees of advance build in.

 

Last edited: Sep 6, 2014

skunk98

Member

• Sep 10, 2014

• #4

Going to start mine today,and was wondering if anyone could give a rough timescale on how long it should take. Mine's an efi. I've got a 3.9 cam and oem followers,timing chain and gears going in.

 

zen

Well-Known Member

Events Planner

• Sep 10, 2014

• #5

all depends upon your skill..but setting tappet preload is a bitch..i assume you have 2 dial gauges to setup tappets and a degree type gauge for cam timing..

 

L

Laptom

New Member

• Sep 16, 2014

• #6

Do you need to set up tappet preload on a standard 3.9 cam?

 

jamesmartin

Well-Known Member

• Sep 16, 2014

• #7

Laptom said:

Do you need to set up tappet preload on a standard 3.9 cam?

Click to expand...

not if its std and heads havent been skimmed

 

skunk98

Member

• Sep 16, 2014

• #8

Managed to do it over 2 days quite well. Didn't use any gauges or any special equipment,just followed haynes manual and common sense. I marked the dizzy position well,and got the timing all smack on,when it went back together.
I changed the timing chain and gears as they were cheap enough from Baermach,made sure everything was cleaned properly before reassembly.and everything oiled that needed it. My old cam was badly worn and I changed the followers which was a no brainer really. When it was started,ti sounded smooth and nice. I'd do another one quicker,now I know what to do,so maybe an uprated one in the future.

 

zen

Well-Known Member

Events Planner

• Sep 16, 2014

• #9

to be honest, i wouldn't bother unless going whole hog with proper extractor headers, silly carb etc...

 

ronsealdeath

Sagging Member

• Sep 23, 2014

• #10

johndregg said:

My V8 3.5 recently crossed 100k miles, she's running well on LPG mostly through two SU carbs, a very old set up. She also is fitted with a nice exhaust system and headers, I'm getting around 320 miles to a 90 litre fill up too. This improvement of about 60miles is down to running advanced timing and having replaced all the leads, plugs, coil etc (can't emphasise enough how important the ignition is on LPG)
I keep reading on here that at 100k the cam in a RV8 should be changed, the timing chain will be slack etc. Now, i have good compression in all 8 cylinders and under the rocker covers is as clean as a whistle, looks like new under there. Should i be changing the cam? And if so, what type? i would like a bit more torque, but maybe a standard overhaul will give me enough? Or i've also read that a 3.9 cam gives a bit extra?
What do you lot recommend? I mainly drive the car on the road but do do a bit of tame laning too.

Click to expand...

Always do the lifters at the same time you change the cam. I read recently that the lifters pick up all the swarf in the oil and form nice little abrasive surfaces for the cam to get chewed up on! So a new cam with lifters in that state, won't appreciate it very much!

 

skunk98

Member

• Sep 23, 2014

• #11

I totally agree with doing the lifters, as it's you've got to take them out anyway. As I'm on a budget, I couldn't go for a better cam.
Hopefully I've attached a picture of my old cam showing the badly worn cam lobe.

 

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G

griffman

Active Member

• Sep 24, 2014

• #12

You must ALWAYS fit new tappets with a new cam.

I hope you followed the 20-minute rule as well - run for 20 mins on gorst start-up between 2 and 3000rpm - don't let it idle..

make sure you put some zinc additive in your oil as well and change the oil and filter after 500 miles.

BTW as Zen says the Kent H180 is best for an auto and the H200 for a manual - real steel viper hurricane good all-rounder suitable for both

 

skunk98

Member

• Sep 24, 2014

• #13

Ran it for about 10mins around the estate,checked for leaks etc, and all ok. Ran it around for 3 days with cheaper oil in,then drained it and put Mobil 2000 semi and slick 50. Now runs very smooth. Not any real noticeable power difference,as it's a standard upgrade cam,but nicer to drive and easier on hills.