3.5 V8 ROVER CYLINDER HEAD TEST

In the video we compared twoV8 Rover engines, both have the same 9.75 compression and mild cams shafts, but one has been uprated with lightly ported 4.6 cylinder heads and some light porting to the inlet manifold

[@1971RoverP6]

Another excellent study Graham! Very happy with your rebuild of my V8 (engine 1 in the video) GAN 340J. Best, Sean

[@nFlames2]

That Buick 215 was a well engineered engine for its time, it whet in to testing back in the late 50's.

[@KompressorPete]

Great video - thanks!
Please share more dyno tests with cams, carbs, heads etc. on the 3.5.
There must be a way to reach higher torque figures porting/flowing the heads and intake and carbs. 260 ft-lb should be possible - or at least a good goal 😊
Has anyone used David Vizards IOP software or his porting strategies on the Rover V8’s?
I would like to do that myself.
That Sound is just unbeatable - Tony Pond at 7.000 rpm in the Manx Rally - goosebumps 😊❤

[@plum66]

Luvvin your spec comparison tests. What effect, either alone or with other mods ca come from using the twin downpipe exh manifolds? These were used on Range Rover EFI engines onwards.
These effectively turn the exhaust system from 8-2-1 layout to 8-4-2-1

[@PenguinMotors]

without doubt there would be a gain in power/torque, how big would depend on the rest of the engine sspecification

[@TechOne7671]

Good experiment mate, shows how the hype isn’t always true. I rebuilt a standard 4.6 for my Westfield and another one with 4.0 pistons and rods to increase comp ratio. The standard one is on the car and I have run up the high comp one in the test bed with no issues although not got it in the car yet. If you weren’t so far away I’d bring the engine to you to dyno run to see the difference on paper. Cheers for the videos.

[@PenguinMotors]

4.6 has quite a low compression ratio as standard, so raising it to around 10:1 should make a big difference, that said a 4.6 makes a lot of torque anyway so i imagine your westfield will have traction issues whatever the compression!

[@tiitsaul9036]

What's the intake manifold like on these engines? I'd assume a classic American 2 plane manifold would perform better. I have no idea what's available for these engines.

[@PenguinMotors]

Standard twin su manifold is a dual plane manifold but it’s pretty ugly so I would imagine if you could make an adapter to fit the standard su carbs to an edlebrook manifold you will find a power gain, that’s something it intend to try at some point

[@bobawatsit]

port matching and radiusing corners in the good old days worked a treat, increased airflow also bumped up CR and overall torque ... not so much now with most 4 valve engines
if your looking for low end TQ/HP do as above advance the STD cam and try 30 deg seats on the IN valve

[@tiitsaul9036]

Interesting as always.
Would Bell mouth on the filter box entry make any difference? Or length of the entry pipe?

[@PenguinMotors]

i dont think a bell mouth would do much, the air box really needs a much bigger intake pipe

[@paulriggers1558]

my old rr has some small headbolts next to the exhausts, this isn't what we are talking about is it?

[@PenguinMotors]

yes, obviously the head bolt holes in themselves make no difference to performance, but the 10 bolt castings are a better design