Top 3.5l V8 DIY Improvements and Upgrades.

[DT-P38]

Hi there,

I have spent my spare time, over a week or so, trying to find info on DIY improvements and upgrades for a 3.5lt V8, with zero success. Thought info would be easy to find in the defender-county section or the good oil, but nothing. Tonnes of stuff on POOMA's and all the other TD's but nothing (I can find) for the little old petrol jobba!!! Feel free to tell me where to go if I am looking in the wrong spots!

The vehicle in question ("The Count") is an '85 County 110 we have recently purchased which looks to be pretty much standard but does already have a set of extractors. I intend to refurb and restore him to original but would like to try and gain a little extra poke with out spending mega bucks on a rebuild.

So what simple stuff can a "have a go" DIY'er realistically do to the 3.5 to help it along? Will definetley be doing the usual service items so for example, is there anything to be gained from spending up on leads & plugs? It is mixer type dual fuel, so is it possible to set up carby running for power? Are there carby tweaks/changes that may help? Any advantage from desludging or fuel or oil additives? Not trying to make him into a drag car, just sort of optimising my spend/efforts where possible.

I really don't know that much about this sort of thing so any comment, direction or advice would be really great!

Thanks, Dave.

[lambrover]

Has is got the factory carbs?

I had a factory V8 county and ripped the engine out and stuck an Isuzu in it, got sick of really bad fuel consumption. Mine had a Holley carb, I think the factory SU's are better though. There is bound to be a some one along soon with more info for you mate.

Sent from my iPhone using Forum Runner

[Pedro_The_Swift]

remember it is a a very old design,,
and only 3500cc's
you will never get it to launch like a 5 litre Jag.
can you remove heads?
clean up the ports, fit a bigger cam and rev it like you stole it,

mine went quite well over 3K

[101 Ron]

Fit later model 4/4.6 litre heads....equals 20 HP.
Up grade camshaft and timing chain.
Look in classic range rover section.

[DT-P38]

Has is got the factory carbs?

I had a factory V8 county and ripped the engine out and stuck an Isuzu in it, got sick of really bad fuel consumption. Mine had a Holley carb, I think the factory SU's are better though. There is bound to be a some one along soon with more info for you mate.

Sent from my iPhone using Forum Runner

Yep it has twin strombergs from what I can tell.

[justinc]

I would recommend as stated a port cleanup and match, a decent cam and an upgrade to the real 'HIF' SU's, not the CD175's you have on there at the moment. They aren't easily tuneable as much, LOTS of needle profiles available for the HIF and a must do if changing cams and exhaust IME.

Also, some of the hi comp 3.5's with decent cam etc can perform very well, even in a big 110.

JC

[DeeJay]

Dave,
You forgot to say it's on gas !!
I'd go for a Edelbrock or marinised Holley and get a secondhand single inlet manifold off a Rangie - they come up on Ebay occassionally & get rid of the twin Strombergs the plumbing is just a bit too complex & restrictive for LPG. Then get it tuned on gas, maybe a cam & better dizzy. That & what Justin says will just about get the best out of it. Have a look at a better exhaust as a last thing..

EDELBROCK PERFORMER MANIFOLD LAND ROVER V8 ED2198 | eBay

Rover v8 4 barrel manifold holley custom | eBay

[justinc]

Dave,
You forgot to say it's on gas !!
I'd go for a Edelbrock or marinised Holley and get a secondhand single inlet manifold off a Rangie - they come up on Ebay occassionally & get rid of the twin Strombergs the plumbing is just a bit too complex & restrictive for LPG. Then get it tuned on gas, maybe a cam & better dizzy. That & what Justin says will just about get the best out of it. Have a look at a better exhaust as a last thing..

EDELBROCK PERFORMER MANIFOLD LAND ROVER V8 ED2198 | eBay

Rover v8 4 barrel manifold holley custom | eBay

ahh, yes well back to single carb for you, then!

jc

[DT-P38]

Dave,
You forgot to say it's on gas !!
I'd go for a Edelbrock or marinised Holley and get a secondhand single inlet manifold off a Rangie - they come up on Ebay occassionally & get rid of the twin Strombergs the plumbing is just a bit too complex & restrictive for LPG. Then get it tuned on gas, maybe a cam & better dizzy. That & what Justin says will just about get the best out of it. Have a look at a better exhaust as a last thing..

EDELBROCK PERFORMER MANIFOLD LAND ROVER V8 ED2198 | eBay

Rover v8 4 barrel manifold holley custom | eBay

Thanks mate!

[lebanon]

I am running a couple of HIF SU Carbs and have changed the the camshaft to a 3.9 type.

Later on I have installed a 4.2L engine fed with the same SU carbs.