Rover V8 3.5L to 4.6L upgrade DYNO TESTED! Rover p6 - Part 7

Back in the day at main dealer we would fit offenhauser inlet with 390 cfm with vac secondarys (or 600cfm) drove so much better and about 6mpg better (19-25mpg). Original inlet manifold was absolute shite....

Fuel consumption?

Hiya bud great video it's something iv been knocking around in my head for a while now iv got the option of doing a SD1 3.5ltr rebuild or go for the 4.6 option the very thing of doing a 4.6 on su carbs and a cam it's for an off road trialing truck the carbs sounded the simplest of options what I was thinking of doing with the SD1 engine was give it a good freshen up with a full lighten and balanced bottom end a cam and some minor port work similar to what you just described the reason I was looking at the SD1 was I believe it has one of the higher compression ratios as standard and I noticed that the 4.6 is lower compression would I be better starting with the 4.6 with and bumping the compression ratio up abit and a cam straight away instead of looking at the SD1 engine also it would be on a manual box, any advice would be gratefully received and once again good video pal

Thanks guys, my dad owns a P5B Saloon, I am usong these sounds for a video game! :)

Fantastic stuff - just love these engines and have always loved the looks of the P6.

It's rather interesting to see how you folks down there deal mainly with small displacement engines and rather small power outputs. Where I'm from right in the middle of th U.S., it's hard to find somebody who builds an engine that's less than 325 cid, or for you metric folks, 5.3l. I personally am gathering parts to build a 470 cid engine, and I feel like it's still small.

there ain't no substitute for cubic inches

I loved the old Rovers... but have also owned 3 TVRs with the RV8s fitted (2 x 390SEs, plus 1x 400SE). Have a look at what TVR and owners of their RV8 cars had done to them, for some extra tips. 👍

probably would have picked up more topend power the 4 barrel carb God intended

Great video

Be interesting to see what the 3.5 with better breathing can do if you get the chance to do one. 👍🏻

I believe this is basically the Buick / Oldsmobile aluminum V8 engine from the early 1960s. Am I correct?

Hello sir please help me with the direction of piston most especially where the word front faces for both sides

Why go to all that trouble and not put a Holley.4 barrel.on I ran 3.5 in an Mgb.for 15 years

Enlarged by stroking?

What sort of price range would it be for an older model Range Rover Classic rebuild, to perhaps 150 hp, and improved torque throughout the range, working mostly with improved efficiency, thus keeping the petrol consumption in the same general region? Is this even possible? :)

I would be very interested to see what a Ford Essex 3.0 engine can produce without enlargement - back in 1984 i recall reading a copy of a British car mechanics type' magazine where someone un-named fettled an Essex to produce 250HP in old money with a set of triple Carbs and possibly some intake and exhaust tampering but not by enlarging the CC. Having owned a RR Classic 3.9 I have to say the V8 was very under welling in terms of torque/power. Yes the RR was heavy and I made adjustments for that but it was a very flacid engine. I took the engine out and replaced the camshaft and followers etc, etc, and it ran very well on completion but other than the sound that V8 is pretty sluggish in my opinion

Excellent video

Sounds wicked and goes well!
3.9 in my mgb is great with edelbrock and headers

Hi, I have a 4.0 liter long block and some 3.5 heads from a RRC. I was thinking a 4 barrel and a mild cam. I was hoping to replace my tired 3.5 liter on my defender. What carb would you suggest in terms of CFM? How many HPs would you guestimate?

Hey, will the 3.5 head gasket fit the 3.9 without issues?

Great video. I am looking at buying a 4.6 to replace to 3.5 in my Rover SD1 VDP EFI

What power output do you think you could you expect from a 3.5L Rover V8 in Stage 3 set up with tubular exhausts?

Hi Graham, great video and great numbers there!!!.
IT is possible to put 4 IDF webers there?

Is having the correct cc of the engine on the log book a necessity for proper insurance cover?

I loved this, what a great video (and series). I've got a '69 Series 1 P6 V8 which has the 3-speed BW35 box. I would take the 4.6 in that set up every time. Why? You can put the 3.5 in '2' which locks the box, and leave it there all the way up to about 65mph from a standing start. It's all torque which still embarrasses a lot of modern cars. Now, with that 4.6, that's rocket ship territory where it all counts from 0-3500 rpms. Then '3' should kick in... I imagine it would pull a p6 easily up to 140mph easy. Not that you would want to without a Police-spec front air splitter.

I saw this engine in an Osca at an autocross back in 1964, it was called a Buick 215 cu. in., I have always been enamored with that engine.

I think that car needs some suspension bushings etc Engine?? A 302 Ford is smaller and makes more power

How about changing them nsu carburettors.. into something more advanced?

Did the bores on P6s exhaust manifolds match the heads on 4.6 ? I had to use a tongue sander on mine similar tho in P5b cast iron but they matched in the end Ps: I had installed a 4.0litre ports were massive compared to standard 10:5;1 P5b which were tiny by comparison

Interesting stuff Graham, I raced a rover V8 powered MK2 Cortina for 30+ years, 3.5 and then 3.9, the final spec was 471 GMC supercharger 650 double pumper Holley, stage 2 high flow heads, blower cam, 7.:1 pistons, Helix clutch and ford T9 4 speed, the best ET was 12.00 @117 mph I never put it on a rolling road but looking at the numbers and the weight of the car I recon it was around 350 - 400 bhp the maximum boost was 5-8 psi , I always wondered what this engine could have been pushed to, what do you think? I sold the car after Shakespeare closed and now have a Camaro.

I don't get it. whats the point if the engine can't breath properly? Its crying out for better carbs and cams surely??

I feel like im watching a usain bolt trying to breathe through a cigarette. Those twin SUs, omg. 50 hp per litre. Pribably could have got those figures out of a standard rover v8 with some cams and a decent intake system? Im not an expert so maybe im wrong.

Back in the day I owned an SD1 3.5 running twin Strombergs but always looking for a bit more power I bought and fitted a brand new 390 cfm Holley carb, offenhouser manifold and Mallory distributor which straight out of the box really improved the bottom end power but the top end suffered a bit which was a bit surprising. Because dyno's weren't round very corner in these days I was happy enough with the low end gains to live with it.

Just shows what it could have been, put together properly!. Nuff said!. 🙂

How about the original Buick engine compared to what has been done to it through Rover.

Buick and the Rover are port limited. They just can not flow the air for higher RPM power.

Want a 5.0...😂

whereabouts are you guys, didn't hear you mention and can't see a website address or link

What sort of budget are we talking about going from 3.5 to 4.6? I have a Land Rover 101 with the standard (low mileage) low compression 3.5 V8 and i'm contemplating upping the capacity but don't know whether to just drop a second hand 4.0 or 4.6 into it or having the original engine capacity modified.

Great Video really enjoyed seeing this! We're looking to engine swap a 4.6 Top hat into a 3.9 V8 Range rover classic, so some interesting information here

I have a TR7 with the 3.5. I would gladly trade up to the 4.6.

I'm a bit late to the party having just seen this and it's not that different to mine - my knackered 4.6 heads were saved with a set of very very slightly bigger valves (ones that don't need new bigger seats) and like you I used the standard cam, carbs, airfilter, etc off the old 3.5. My 3.5 exhaust manifolds had been built for looks from box section and I thought were awful for flow but I still got the same as you, 201bhp and 291lb/ft so maybe they're not so bad after all. The difference in driving is just staggering, it's definitely the best engine mod you can do IMHO. 4mpg better fuel consumption too :)

Great video, thanks for sharing it - can't argue with those numbers! That torque is gonna make a 1275kg car move alright. Reading about this conversion and talking to a few people, with a manual car you will eventually break the half-shafts if you use it in anger. To my knowledge most of the drivetrain isn't that different from the 90BHP 4 cyl, so I'm surprised it copes as well as it does, but no escaping the fact it's much weaker than the SD1 which was engineered from the start for the V8. I'm guessing anyone seriously contemplating this is NOT running the notoriously weak 4 speed manual or the BW autos which are pretty much on the limit. The final drive (which has only an extra pair of planet gears) and UJs are going to have a drastically reduced lifespan I'd suspect.

torque

Great upgrade - would have been good to do straight comparison with all the different exhaust manifolds P5B - P6 you've done - twin pipes from SD1 & range rover - MG RV8 and a typical aftermarket 4 into 1. Another good comparison would be - SUs you've done - Stromgergs - 2 barrel 38dgas - 4 barrel weber & holley and injection. Please more honest videos

What happens with the crank? Is it shorter? As far as i know the cam will need to be longer for the distributor

This 4.6 sounds beautiful ❤