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

[@paulholtom7317]

Very nice! I have a 4.6 with Edelbrock 500cfm carb and Edelbrock intake manifold port matched to a pair of stage 3 ten bolt heads, Stealth cam and mapped ignition (MSD 6AL-2 programmable). With free flowing headers it made 325 ft lbs of torque at 4000 rpm. Over 300 ft lbs between 3000 rpm and 5000 rpm topped out at 315 bhp @ 5800.

[@sidecarbod1441]

Show off!

[@No.Handle31]

I want to do this type of build for my friends Land Rover. But he is being an idiot and going with the Diesel engine from a P38.

[@waheedkhunji7475]

Did stealth camshaft good ?

[@paulholtom7317]

@@waheedkhunji7475 I'm happy with it. However not really compared it with other fast road cams available.

[@sydsnott5042]

Niiiiiiice. 👌👍

[@terran5569]

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.

[@towgod7985]

Always enamored with the Buick 215 / Rover 3.5. One of the most underated engines of all time. You chose well. Cheers.

[@darrenhowes4720]

This 4.6 sounds beautiful ❤

[@brianmac8260]

Cor blimey! Just as well the Rozzers hadn't got one of these! Just kidding, amazing job Graham!.

[@daveshongkongchinachannel]

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

[@performancedownunder5773]

I’ve had several P4’s which I guess are my style of car, a 3 litre coupe’P5 and an SC2000. I did look at a V8 P6 but was put off by the way the guy just started it up and revved it right out. I just thought if that’s the way he treats it I’ll stay away. That’s the closest I got to owning one. Ultimately I was put off the P6 because the one I owned couldn’t handle corners in the snow in the Devon countryside. The P4’s were absolutely brilliant, having been careless enough to put one in a ditch, I was fortunate enough to be able to put it in reverse and get out. The lesson for me at the time I guess was that the P6 wasn’t exactly a country bumpkins car, even a V8. I’m talking now about hills and corners that need a rev to get up in the snow and handling to stay on it, I just felt that the P6 was a little too long in the wheelbase for my needs at the time. The ditch didn’t happen in the winter. Nonetheless the P6 is an absolutely beautiful car to drive, the open roads of West Australia would suit them perfectly, and that V8 is the most beautifully tuned I have ever personally heard, and the way it was respectfully revved is how I would treat my own car cold. Always a pleasure to watch your videos, relaxed, informative, and just really enjoyable. Thanks for that.

[@PenguinMotors]

thanks for the feedback, i like to test, not wear out or break engines. I like to bare the owner and final use in mind. there no point in pushing the rpm to the limit if that not how its going to be used.

[@davidgerrard8661]

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

[@normannippy8471]

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.

[@goratgo1970]

Quite interesting read for me as I have the new Holley carb. but like to know if the Offy manifold you have is the split plane? For distributor I got the HEI and an MSD box.

[@normannippy8471]

If I remember correctly it was an offenhouser dual plane inlet manifold. It ran like a clock with the holley, much better than the twin carb setup and a coin would sit on its edge on the rocker cover when idling but top speed was down slightly maybe 5mph and I could almost feel it holding back at full revs but I dare say different jetting would have solved that problem. It was really good on fuel too if driving sensibly but lucky to get 10 to the gallon flat out.@@goratgo1970

[@Predator27007]

What an excellent video

[@PenguinMotors]

thanks

[@malcolmwhite6588]

@@PenguinMotors no, the Americans don’t say “there ain’t no substitute for cubic inches!” that doesn’t rhyme and sound American LOL they say, “there ain’t no replacement for displacement”! 😂

[@kennyh5083]

I am not positive but I believe by.. changing the Cam, and timing cover you can convert the newer late model Aluminum Rover V8's to use a distributor. Is this true???@@PenguinMotors

[@freddieparrydrums]

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

[@grahamw56]

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. 👍

[@isickofit]

Graham! This is a great vid! Excellent editing and top content. It's been too long since I visited Penguin central. Liked. Subscribed and catch up soon I hope.

[@DarrenGroves]

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

[@Bombardier9011]

Excellent video

[@twin40dave]

Wow what a difference, nice job guys well impressed 👏

[@IanS-o3j]

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 :)

[@PenguinMotors]

Yes my client reported improved fuel consumption too

[@ThatsClassiccars]

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

[@gileshamilton4462]

Just think what it would do with a free flowing heads , cam and 4 barrel webber !!! owe and a nice set of ex manifolds ... knocking on the door of 330 im guessing and not far off that in torque if not a tad more !

[@PenguinMotors]

it would certainly be interesting to find out

[@stewartnoel9810]

Great video

[@koitorob]

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.

[@PenguinMotors]

you can enlarge a 3.5, but you cant actually make a 3.5 into a 4.6, so if you want a 4.6 you have to start with a 4.6 bottom end. you can use your 3.5 heads timing covers, ancilleries etc on a 4.6

[@adamhall2530]

Great video Graham how's about a standard but stroked pinto

[@PenguinMotors]

its in the pipeline

[@adamhall2530]

I'd also highly recommend the burton bf63 cam which never seems to get much coverage but them that have it always highly rated it my self included its got a very long spread pf power and produces a lot of talk torque and from reasonably low down 2

[@martynwhite3811]

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

[@PenguinMotors]

Some of that will be coming in the nearish future, problem is without going down the route of channel sponsorship it’s simply too expensive to do that sort of testing unless I have a clients project which lends itself to doing some testing

[@bertiewooster3326]

I have mgbgtv8 standard 3.5 engine apart from 4 branch tubular exhaust on the Northampton Motorsport RR produced 160BHP at 5000rpm .

[@PenguinMotors]

is it an original Bv8 low comp lump? 160 sounds strong if it is :) did you use RV8 or block hugger manifolds?

[@bertiewooster3326]

@@PenguinMotors It is original engine and heads (35k), the manifolds are tight to the engine no holes have been cut in body still on SUs but lot of time spent on getting them jetted correctly poppet valves on carbs removed car goes really well lazy to drive as well the MGBGTV8 is potentially a wolf in sheep's clothing for little money.Standard cam.

[@PenguinMotors]

@@bertiewooster3326 thats good :)

[@VintageCustomCars]

Nice builds, i also just started my V8 Rover P6 after 20 years :) will see how the engine behaves, maybe will do some mods. Greetings from Vilnius

[@PenguinMotors]

thanks Good luck!

[@kennyh5083]

I want to give you some of my money in exchange for some basic info on these Rover Aluminum V8 engines! Plz tell me how I can do this?@@PenguinMotors

[@MichaelThomas-be7gq]

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.

[@PenguinMotors]

the 4.6 almost makes the gearbox redundant!

[@user-fd1sd7hr9o]

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

[@PenguinMotors]

Its in the pipeline, but got to work my way through a stack of clients engines before we can "play"

[@user-fd1sd7hr9o]

@@PenguinMotors less you tubing more working then 😝😝😂😂😂

[@barryhuddlestun3098]

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

[@peterbroad1772]

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.

[@PenguinMotors]

I know at least one 4.6 fitted to a bw65. It seems ok, but to be honest it’s always going to be a case of how hard it’s used. Same for running a 4 speed manual the gears are reasonably wide, so if driven with sympathy I wouldn’t expect to to immediately expire, that said the one this video was about was fitted with an LT77 and so is my own car which is waiting for a 4.6 transplant

[@peterbroad1772]

@@PenguinMotors Awesome. The thing is, if I had this conversion, would I use it "sympathetically" at all times - with ~£5k of engine work on the table - of course I wouldn't! I have a tuned 3.5, it's not fast but TBH I think in some way it might miss the point in this type of car. What's disappointing driving it, is the thing just doesn't rev. So given the practical limits of the car (for a start you can only really run 205 tyres), there might be a good case to make a "fast road" car that's more "playful" and willing to rev, rather than being outright fast - oh and a sharper throttle response than SUs give might be nice. This comes from driving Stags. I was really disappointed at standard Rover conversions, as the engine couldn't be more different than the OHC Stag engine. OK admittedly the fact the Rover will stay in one piece is a big plus - but the Stag, with similar power to the 10.5:1 Rover will spin up to 6,500 fairly easily and there is actually a purpose to going above 4000. In real A/B roads with bends and 60mph limits, this is far more fun than driving it like an EV and really these are playthings rather than transport these days.

[@pokebass1]

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.

[@PenguinMotors]

reason is we dont really have any large capacity engines

[@Goober-o3n]

It's not so much the capacity..its what you do with it...most v8 rover motors end up in cars that don't weigh 2 ton...so they don't need a big block....there was a chap in the 1980s and 90s called Steve Green....ran a mk1 cortina with a v8 rover....the last incarnation of that car before it was wrote off( the original mk1 ...not the spaceframe one)... had a 5ltr rover...that did low 9s over the quarter ..and stood on its ass when he launched....that car..driver...and engine is legendary.....check him out..there's still videos on KZbin..

[@iava1981]

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

[@PenguinMotors]

absolutely you could, id love to try a set but its a hideously expensive setup

[@robleary3353]

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

[@TbsDltn]

😎 👍...that mill needs some wildcat heads me thinks

[@PenguinMotors]

that would help, what it really needs is an induction upgrade :)

[@thomasschaefer9312]

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

[@andypdq]

Interesting video, at the moment I'm doing the same with an SD1, I was recently given a 4.6 which was stored in a building which caught fire, rocker covers and plenum top were melted in places, but the short engine seems ok. I'm thinking 4.0 pistons, to give it a bit more compression, 4 barrel carb and intake, mild road cam, I have some ported heads from a 3.5, I have Rimmer bros tubular headers and sports exhaust on the car. In the RR the 4.6 made 220 hp, I'm hoping for 250 hp and 300 lb ft with these mods. Am I being too optimistic? Subscribed.

[@PenguinMotors]

sounds reasonable

[@markellis796]

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.

[@PenguinMotors]

i would of guessed you had something like 350bhp, but the torque would of been huge, you must of broken a good few T9's. Natrally aspriated its always going to struggle to make real big numbers, the engine simply doesnt flow air well enough to make real power and they dont take kindly to high rpm with, but with forced induction i would of thought 600bhp wouldnt be too hard to achieve.

[@markellis796]

@@PenguinMotors Thanks for the reply, yes broke a few gearboxes, props, axles, clutches, bellhousings.. the limiting factor was really upgrading the drivetrain to accept more power, I was going for a Tremec 600 but when Shakey and York closed I lost interest, I know of one guy that ran 30psi of boost on methanol with his rover that was pushing out well over 1000 BHP and ran in the 7's with a Pop, outa my price range though ££

[@darrenhowes4720]

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

[@PenguinMotors]

Crank is actually longer and requires a spacer when used with p6 timing cover and cam. For cam use 3.5/3.9 long nose cam

[@poodumrover1]

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

[@PenguinMotors]

yes they did

[@BackPackMac]

I have a 3.5 and would like to do what you have done. So to be clear: you have replaced the bottom end and heads? Did you keep the upgraded cam from the 3.5? did keep all ancillaries including oil pump?

[@PenguinMotors]

Yes all the 3.5 ancillaries fit sump/cam/ timing cover oil pump everything fits. If you fitting it to a rover p6 with power steering you need to cut a tiny bit away from the power steering bracket, and drill out a hole in the alternator bracket to take a larger diameter bolt, same with the engine lifting brackets

[@assistantto007]

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

[@PenguinMotors]

probably, but seeing as the car is now driving around in America I don't suppose its relevant

[@andy1way]

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

[@PenguinMotors]

hard to say, aside how well the cylinder heads actually work, cam and induction choices will make a big difference, you could easily be somewhere between 250-300bhp

[@MrRossKendall]

want an edelbrock 500 and manifold to test it on it? can drop it round. i got a 3.9 in the escort but my exhausts are horrible, mgb blockhuggers

[@PenguinMotors]

Ross it would be great to of done that test, but time doesnt allow, that car is already being prepped ready for shipping to America where it will now live. That said there will be more v8 builds in the pipeline so you never know it could come in handy.

[@MrRossKendall]

@@PenguinMotors well you know i got it if you want to test it.

[@1957powerwagon]

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?

[@PenguinMotors]

4 barrel carbs are not really my thing but I would suggest Holley 390 or Weber edlebrock 500

[@devonrod]

Great video, I notice the P6 was a 3500S, does that mean the exhaust manifolds on the test engine were the larger bore ones that were fitted to the 3500S ?

[@PenguinMotors]

It was the 3500s manifolds fitted for the test

[@devonrod]

@@PenguinMotors I have a brand new 4.6 in my car, its got a Crane 1/2 race cam, twin Ford 2.5 V6 34 DGAS weber carbs that have 24mm venturis, on a very rare twin two barrel Edelbrock inlet manifold, I have the standard smaller bore P6 exhaust manifolds and a twin 2 inch stainless exhaust with balance pipe and straight through silencers, it goes really well, I am guessing the smaller P6 exhaust manifolds are fine except for higher revs, any thoughts ?

[@PenguinMotors]

I don’t think the smaller manifolds will make much difference especially if mated to the bigger bore exhaust. But I do think you would be a lot better off with the 38dgas carb or probably better still a 40DF15 carb

[@devonrod]

@@PenguinMotors Thanks Graham, that was my conclusion about the exhaust too ! I have a pair of the bigger bore exhausts but they have been cracked and welded so I was reluctant to install them, the twin 34 DGAS carbs are fine, I have a good pair of 38 DGAS that I might try some time.

[@PenguinMotors]

@@devonrod i guess you know the JR Wadhams have reproduced s manifolds, they are not cheap but are good replicas

[@willdatsun]

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

[@PenguinMotors]

That’s because engine work is a side line and I already have more to do than I can handle

[@MorningNapalm]

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? :)

[@PenguinMotors]

To get 150 bhp All you really need to do is rebuild it with with high compression pistons

[@No.Handle31]

I have a question a friend of mine wishes to build a off road buggy. Wants to use a later Rover V8 4.0 EFi . Is this a good way to for power and reliability or should we stick with good old fashion carbs?

[@PenguinMotors]

Both can be very good, it’s hard to beat the simplicity of carbs in terms of it’s easy to get an engine up and running on them, but done right efi does have its own benefits in terms of efficiency etc, I would say you friend should go with whichever he or whoever will tune it is most familiar with

[@No.Handle31]

@@PenguinMotors Thanks for the information cheers.

[@grahamw56]

Have a look at the TVR 400SE installation (I've owned one, plus two TVR 390SE's). From experience... very reliable. My 400SE made an honest 240bhp and 250lbs of torque on the rolling road, but was also good on fuel, and a smooth drive.

[@garybrown4854]

I would like to see that done to a P5B

[@PenguinMotors]

There’s a few P5’s with 4.6 fitted, they are ok in straight line!

[@burtvincent1278]

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

[@PenguinMotors]

Correct

[@raytarrant514]

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....

[@stevek3036]

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

[@PenguinMotors]

over the years ive worked on a fair few Essex V6 engines, but ive never actually rebuilt or done any performance modifications on one. my understanding 230 odd bhp isnt too hard to get

[@AMMARONE65]

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

[@PenguinMotors]

I will do, it’s just most of my clients prefer the original SU carbs

[@AMMARONE65]

@PenguinMotors True that such vehicles need to be kept original .. but believe me if you would do an advanced module they would love it .. respect to what you do. Keep it up ..

[@juniorkaciru9123]

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

[@PenguinMotors]

Front would be towards timing chain end of engine

[@juniorkaciru9123]

@@PenguinMotors hello,, thanks what about for a range rover 3.5l v8 direction of pistons written front for both sides please

[@juniorkaciru9123]

Also which side should the dowels face on the block

[@PenguinMotors]

you mean the ones which locate the heads? pointy end up

[@juniorkaciru9123]

@@PenguinMotors hello please can I have your email so that I can send to you the pictures that I need your help

[@nickflick3938]

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

[@PenguinMotors]

No you can’t use a 3.5 head gasket on a 3.9 because of the bigger bore on the 3.9. But you can get 3.9 gaskets in steel or composite

[@vannesharose6604]

@@PenguinMotors ok thanks for replying... unfortunately I already ordered the gasket; however I have a 3.5 engine but ordered a 3.9....am I at an all lost situation?

[@PenguinMotors]

you could use a 3.9 gasket, but its not ideal, gaskets are cheap anyway

[@vannesharose6604]

@@PenguinMotors ok thanks again, I agree the are cheap online; I live in the Caribbean which makes it costly to get here

[@paulwisdom5383]

How much do these 3.5s share with the later range rover 4.6 V8?

[@PenguinMotors]

Tappers, rocker assemblies and push rods are the only truly same parts, but the heads will interchange and all the earlier components such as sump, timing cover, cam, timing gears will fit in the later 4.6 block

[@ldnwholesale8552]

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

[@PenguinMotors]

The car it went in had an uprated anti roll bar and shocks and actually was quite good. 302 wasn’t an option

[@paulrunell7821]

torque

[@sailinggreenpearl2571]

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.

[@PenguinMotors]

hp yes, torque not a chance

[@element271]

What CR and cam are you using? Thanks

[@PenguinMotors]

it was Standard 4.6 compression, which is i recall correctly is 9.37:1, cam was a newman Ph1

[@element271]

@@PenguinMotors there are 8.37 CR pistons and 9.35 CR pistons depending on country and year. Do you recall? I am building a 4.6 with the same carbs at the moment.

[@PenguinMotors]

@@element271 CR was defiantly 9.3, if it were in the 8's i would of done something to give it more compression

[@element271]

@@PenguinMotors ok thanks.

[@mikethompson7296]

Can you cure the air starving by fitting 2" SUs off a Jaaag?

[@PenguinMotors]

2 inch carbs are an option on one of these, But the factory air cleaner and poor intake manifold are a bigger restriction than the 1.75 inch su's

[@alex79buckland]

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

[@PenguinMotors]

The 4.6 does have a lower compression 9.37 from memory, but it’s easy to raise it a bit. Sometimes a low compression can work in your favour though, if you use full throttle at very low rpm and a high load the lower cr is better as the engine will just get on with it. Same conditions and high compression it tends to stall or pink. Either way the the 4.6 give so much more torque it’s a far better starting point

[@alex79buckland]

@@PenguinMotors thanks pal would you recommend a piston to bump up the compression if I go that route and is there a cam that you would recommend for response abit more peppy than a standard cam

[@PenguinMotors]

If you’re going 4.6 route just use steel head gaskets that will give you about half a ratio compression, provided the sealing surfaces are good steel gaskets are as good as the composite ones. If you want grunt right at the bottom of the Rev range I would suggest a Newman ph1

[@alex79buckland]

@@PenguinMotors Yeah grunt from the bottom but also to pull through the Rev range Iv had a 3.9 disco V8 but on a twin su setup and a 3 speed auto from early rrc and I wasn't that impressed with the engine but I think it was a little tired and the auto box I just couldn't get on with I was more impressed with the 300tdi setup I had in another truck but I'm wanting to build my own setup rather buy a truck with someone else's setup plus the V8's sounds beautiful and it's an itch that needs to be scratched yano 😉 it's a toy for a hobby and it's fun to be a big kid on times aswell as following a disaplin

[@PenguinMotors]

@@alex79buckland ph 1 cam sees torque fall off fast after a little over 3K on a 4.6 so perhaps go one more? ph2?

[@dkdjfr]

Enlarged by stroking?

[@PenguinMotors]

4.6 has bigger bore and stroke

[@dkdjfr]

@@PenguinMotors I was thinking if it was a stroked 3.5 l engine.

[@buggerlugz6753]

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

[@PenguinMotors]

the point is we were not allowed to fit better carbs, but that aside the extra torque is very noticable even with restricted intakes

[@MrSpitfireMustang]

Fuel consumption?

[@PenguinMotors]

What about it? I’d your worried about fuel consumption don’t have a V8! Although In fact the owner reported the 4.6 to be using less fuel than the 3.5. Used to

[@MrSpitfireMustang]

@@PenguinMotors Yeh, just interested. Why stick with stock low compression, high consumption. Not a criticism just a query.

[@PenguinMotors]

@@MrSpitfireMustang TBH we could of given it more compression, but the car drove really well, and we are already pushing the boundaries of what the the cars chassis and running gear can cope with

[@MrSpitfireMustang]

@@PenguinMotors Cool. Fair enough.

[@daledavies2334]

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

[@daviddonoghue5438]

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

[@PenguinMotors]

Because the client was taking the car back to america with him, you cannot import a modified car into the USA

[@marshgatelaneposse]

Mmmmmm pro charger

[@Arthagnou]

seems to be alot of lost Horse Power. 9.5:1 pistons, roller lifters and rockers along with a real exhaust probably add 50-100hp if you rev it to 7k

[@PenguinMotors]

you dont need roller rockers or 7k to add 100bhp, but that wasnt the brief

[@nicholasagnew2792]

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

[@PenguinMotors]

4 barrel would of probably picked up a bunch more power although we weren’t allowed to fit one because it wouldn’t of been factory original

[@breebw]

there ain't no substitute for cubic inches

[@kenjohnson6338]

Want a 5.0...😂

[@PenguinMotors]

to buy? to test?