Omega Owners Forum

Chat Area => General Car Chat => Topic started by: peter the butcher on 22 April 2013, 09:05:35

Title: V8
Post by: peter the butcher on 22 April 2013, 09:05:35
was having a disscusion with a friend, and we were talking about my old favourite beastie, a Rover SD! Vitesse 3.5 twin plenum. I had the fuel injection removed, and replaced with a 4 barrel Holley carb, stage 3 heads and the normal cam. On the bench it got to 260 BHP :) , not to bad, a 60 increase on standard. Are the any still out there tho? not seen one for a long time now

Peter
Title: Re: V8
Post by: peter the butcher on 22 April 2013, 09:09:24
oh, forgot, it also had a stainless sports exhaust from tubular manifolds to the tail pipe, nothing fancy, just a single tailpipe, but sounded marvelous on full chat in a tunnel or underground carpark :D
Title: Re: V8
Post by: Marks DTM Calib on 22 April 2013, 09:14:21
Thats a rare power increase for the asthmatic Rover V8 and as good as many TVR's with greater cc.

The fuel injection is capable of giving more power than the carb to
Title: Re: V8
Post by: Elite Pete on 22 April 2013, 09:48:05
I had a TR7 convertible with a 3.9 V8, which had been tinkered with, that also had a 4 barrel holley, Offenhauser manifold, 4 branch manifolds and gave me a stiffy whenever I thrashed it :)
Title: Re: V8
Post by: Sir Tigger KC on 22 April 2013, 09:49:45
I had a TR7 convertible with a 3.9 V8, which had been tinkered with, that also had a 4 barrel holley, Offenhauser manifold, 4 branch manifolds and gave me a stiffy whenever I thrashed it :)

Take it that was a few years ago then Pete?  :)
Title: Re: V8
Post by: Elite Pete on 22 April 2013, 09:51:05
I had a TR7 convertible with a 3.9 V8, which had been tinkered with, that also had a 4 barrel holley, Offenhauser manifold, 4 branch manifolds and gave me a stiffy whenever I thrashed it :)

Take it that was a few years ago then Pete?  :)

It's been a while since i've seen the old boy ::) ;D ;D
Title: Re: V8
Post by: YZ250 on 22 April 2013, 10:05:30
was having a disscusion with a friend, and we were talking about my old favourite beastie, a Rover SD! Vitesse 3.5 twin plenum. I had the fuel injection removed, and replaced with a 4 barrel Holley carb, stage 3 heads and the normal cam. On the bench it got to 260 BHP :) , not to bad, a 60 increase on standard. Are the any still out there tho? not seen one for a long time now

Peter

I had a Moonraker Blue 3.5 Vitesse twin plenum for about five years.  :y

I know of two fully restored SD1's. One is a 3.5 Vitesse TP and the other is a 3.5S.  :y When I say fully restored, I mean stripped right down to the bare chassis with all panels removed to leave just the framework. They have both spent in excess of £12K rebuilding these cars.  :o :o
Panels can be sourced from India I believe. Although I wouldn't do it, you've got to admire the dedication of people that do this.  :y
Title: Re: V8
Post by: Marks DTM Calib on 22 April 2013, 11:37:19
Its interesting to note that the twin plenum (which is actualy a single plenum with twin throttles) added pretty much no agin to engine output when compared to the Vitesse power plant.

With some tuning the setup becomes more useful but in reality, the throttle was never the big restriction.

Rover V8's have a major issue and that is the head design, porting etc helps but bottom line is that for big gains you need new heads (there are now some available!).

If you consider a 3.5 with stage 3 heads which have improved gas flow and slightly larger valves (gets you close to the original Buick heads ability before Rover buggered the design up), throw in a typhoon or hurricane cam (or similar e.g. 285 although the racey ones make them idle VERY badly), toughened timing chain, rhodes lifters and the like then your still not reaching the point where the throttle is limiting and interestingly, from my experience, these rarely see above 230-240 on a dyno with EFi.
Title: Re: V8
Post by: omega3000 on 22 April 2013, 12:01:47
Still a few around on the auction sites and some tasty ones that have had a lot spent on them ... love these cars but think i would shove a chev v8 in it and be done with it ..
Title: Re: V8
Post by: peter the butcher on 22 April 2013, 13:32:04
I had a TR7 convertible with a 3.9 V8, which had been tinkered with, that also had a 4 barrel holley, Offenhauser manifold, 4 branch manifolds and gave me a stiffy whenever I thrashed it :)

Take it that was a few years ago then Pete?  :)
yeah, it was about 8 years since
Title: Re: V8
Post by: peter the butcher on 22 April 2013, 16:21:50
Its interesting to note that the twin plenum (which is actualy a single plenum with twin throttles) added pretty much no agin to engine output when compared to the Vitesse power plant.

With some tuning the setup becomes more useful but in reality, the throttle was never the big restriction.

Rover V8's have a major issue and that is the head design, porting etc helps but bottom line is that for big gains you need new heads (there are now some available!).

If you consider a 3.5 with stage 3 heads which have improved gas flow and slightly larger valves (gets you close to the original Buick heads ability before Rover buggered the design up), throw in a typhoon or hurricane cam (or similar e.g. 285 although the racey ones make them idle VERY badly), toughened timing chain, rhodes lifters and the like then your still not reaching the point where the throttle is limiting and interestingly, from my experience, these rarely see above 230-240 on a dyno with EFi.

that figure was given to me by the engine people up here in doncaster, when I went to see what they had done, I personally never had it tested in the car.
just a note tho, I was thinking at the time of putting a "blower" on it along with a "fast road cam" that Rimmer Bros had in there brochure, but like a lot of things then, money ran out and it was not achieved :(

Peter
Title: Re: V8
Post by: Marks DTM Calib on 22 April 2013, 16:39:44
If it had the heads and a standard cam then it would be barely over 210bhp at best as its the cam that unlocks the head work.

The 3.5 cam as fitted is pretty poor (the twin plenum didn't get anything special here) to the point that even the 3.9 Efi cam gives an improvement.
Title: Re: V8
Post by: dbug on 22 April 2013, 16:53:18
Remember stuffing one of these V8s into an MGB many years ago (before MG offered a V8 version), had flowed, balanced and ported heads, a "half-race" cam, holley carb - around 225 bhp.
Title: Re: V8
Post by: Elite Pete on 22 April 2013, 17:06:53
It wasn't all about the power in my TR7. Get the roof off and with it being low with stiff suspension and the noise of the V8 it felt like you were doing 200mph :)
Title: Re: V8
Post by: dbug on 22 April 2013, 17:16:34
It wasn't all about the power in my TR7. Get the roof off and with it being low with stiff suspension and the noise of the V8 it felt like you were doing 200mph :)

Was a shame the TR7 didn't follow Harris Mann's original designs which were stunning - got changed, for the worse, due to US market needs.  Originally designed to be fitted with a V8, and again finances dictated a 4 pot, until the emergence of the TR8, and various Grinnalls.
Title: Re: V8
Post by: Elite Pete on 22 April 2013, 19:13:15
It wasn't all about the power in my TR7. Get the roof off and with it being low with stiff suspension and the noise of the V8 it felt like you were doing 200mph :)

Was a shame the TR7 didn't follow Harris Mann's original designs which were stunning - got changed, for the worse, due to US market needs.  Originally designed to be fitted with a V8, and again finances dictated a 4 pot, until the emergence of the TR8, and various Grinnalls.

Believe it or not, the first TR8 was built in 77-78 and only made for the american market which is a shame because it was loads better than the TR7 :'(
Title: Re: V8
Post by: dbug on 22 April 2013, 22:00:34
It wasn't all about the power in my TR7. Get the roof off and with it being low with stiff suspension and the noise of the V8 it felt like you were doing 200mph :)

Was a shame the TR7 didn't follow Harris Mann's original designs which were stunning - got changed, for the worse, due to US market needs.  Originally designed to be fitted with a V8, and again finances dictated a 4 pot, until the emergence of the TR8, and various Grinnalls.

Believe it or not, the first TR8 was built in 77-78 and only made for the american market which is a shame because it was loads better than the TR7 :'(

Believe it as I have been a TR Register member for nearly 40 years.  But did you know prior to 1978 approx 150 prototype TR8s built using the SD1 V8 - the first being made in 1972.  These prototypes, generally unbadged, were sold off by BL (most in UK) on the second hand market.  The TR Register holds full records of all TR8 manufacture.  As you say most of the production models made were destined for the US and Canadian markets, although a number stayed in UK.  Believe the V8 drophead came out 1978, and were based on the original Harris Mann designs (original designs were for dropheads not fixedheads) - these are quite rare now.
Title: Re: V8
Post by: henryd on 22 April 2013, 22:04:10
It wasn't all about the power in my TR7. Get the roof off and with it being low with stiff suspension and the noise of the V8 it felt like you were doing 200mph :)

Was a shame the TR7 didn't follow Harris Mann's original designs which were stunning - got changed, for the worse, due to US market needs.  Originally designed to be fitted with a V8, and again finances dictated a 4 pot, until the emergence of the TR8, and various Grinnalls.

Believe it or not, the first TR8 was built in 77-78 and only made for the american market which is a shame because it was loads better than the TR7 :'(

Believe it as I have been a TR Register member for nearly 40 years.  But did you know prior to 1978 approx 150 prototype TR8s built using the SD1 V8 - the first being made in 1972.  These prototypes, generally unbadged, were sold off by BL (most in UK) on the second hand market.  The TR Register holds full records of all TR8 manufacture.  As you say most of the production models made were destined for the US and Canadian markets, although a number stayed in UK.  Believe the V8 drophead came out 1978, and were based on the original Harris Mann designs (original designs were for dropheads not fixedheads) - these are quite rare now.

The drop top is quite a looker compared to the tin top.
Title: Re: V8
Post by: dbug on 22 April 2013, 22:14:55
It wasn't all about the power in my TR7. Get the roof off and with it being low with stiff suspension and the noise of the V8 it felt like you were doing 200mph :)

Was a shame the TR7 didn't follow Harris Mann's original designs which were stunning - got changed, for the worse, due to US market needs.  Originally designed to be fitted with a V8, and again finances dictated a 4 pot, until the emergence of the TR8, and various Grinnalls.

Believe it or not, the first TR8 was built in 77-78 and only made for the american market which is a shame because it was loads better than the TR7 :'(

Believe it as I have been a TR Register member for nearly 40 years.  But did you know prior to 1978 approx 150 prototype TR8s built using the SD1 V8 - the first being made in 1972.  These prototypes, generally unbadged, were sold off by BL (most in UK) on the second hand market.  The TR Register holds full records of all TR8 manufacture.  As you say most of the production models made were destined for the US and Canadian markets, although a number stayed in UK.  Believe the V8 drophead came out 1978, and were based on the original Harris Mann designs (original designs were for dropheads not fixedheads) - these are quite rare now.

The drop top is quite a looker compared to the tin top.

Absolutely :y

As I said the original designs (droptop) were stunning, but BL went with the fixed head (droptops were a no no then in the US) and completely fecked up Harris's original designs, changing the proportions etc.  It became shortened (and looked stunted as a result).  Harris was a TR enthusiast, owning a TR6, and designed the TR7 as an improvement to the TR6.  It turned out not to be and for many years the TR Register wouldn't recognise the TR7 as a TR!!  So TR7 owners were excluded over that period.
Title: Re: V8
Post by: symes on 22 April 2013, 23:05:20
Why spend all your cash into a 3.5-better off getting 3.9 or 4.2 dont bother with 4.6 as for some reason its weaker-so I was told by Land rover specialist or go 5 liter like I have ;) But mine is Buick not rover-as prototypes were done that way-S.U carbs were fitted because Holley would'nt deal :y And I know 3 people with sdi rovers-1 is 3.5 and other two are 3.9 ex plod
not my favourite rover though as suspension was not as good as p6 IMO this is mine
(http://i1181.photobucket.com/albums/x429/sy427/rover%20p6/blackrose014.jpg)
(http://i1181.photobucket.com/albums/x429/sy427/rover%20p6/blackrose017.jpg)
Title: Re: V8
Post by: dbug on 22 April 2013, 23:53:59
OMG - are they furry dice I see? ::)
Title: Re: V8
Post by: Elite Pete on 23 April 2013, 07:06:01
It wasn't all about the power in my TR7. Get the roof off and with it being low with stiff suspension and the noise of the V8 it felt like you were doing 200mph :)

Was a shame the TR7 didn't follow Harris Mann's original designs which were stunning - got changed, for the worse, due to US market needs.  Originally designed to be fitted with a V8, and again finances dictated a 4 pot, until the emergence of the TR8, and various Grinnalls.

Believe it or not, the first TR8 was built in 77-78 and only made for the american market which is a shame because it was loads better than the TR7 :'(

Believe it as I have been a TR Register member for nearly 40 years.  But did you know prior to 1978 approx 150 prototype TR8s built using the SD1 V8 - the first being made in 1972.  These prototypes, generally unbadged, were sold off by BL (most in UK) on the second hand market.  The TR Register holds full records of all TR8 manufacture.  As you say most of the production models made were destined for the US and Canadian markets, although a number stayed in UK.  Believe the V8 drophead came out 1978, and were based on the original Harris Mann designs (original designs were for dropheads not fixedheads) - these are quite rare now.

TRDC for me, i've always loved the TR7/8  :)
Title: Re: V8
Post by: Marks DTM Calib on 23 April 2013, 08:23:20
Why spend all your cash into a 3.5-better off getting 3.9 or 4.2 dont bother with 4.6 as for some reason its weaker-so I was told by Land rover specialist or go 5 liter like I have ;) But mine is Buick not rover-as prototypes were done that way-S.U carbs were fitted because Holley would'nt deal :y And I know 3 people with sdi rovers-1 is 3.5 and other two are 3.9 ex plod

4.2 engine is a very rare beast, not a great deal made as they used the old Iceberg diesel block (so a similar block to the 4.0 and 4.6 note the 4.0 is the same cc as the 3.9)

The 3.9 and 4.6 share a common 94mm bore with the 4.6 being a longer stroke. The bottom end on the 4.0 and 4.6 is FAR superior to the early 3.5/3.9 with much improved heads and the fewer head bolts (which is considerably better). Add to that a much better fuel pump setup and an improved fuel injection system and you get a better lump.

The only issues I have seen on the 4.6 is dropped liners (normaly following over heating or when run on  buggered cam for any length of time) but you also see this on the 3.9.

If going for a 5 litre then the 4.6 is the place to start as the extra bottom end strength is needed to stop the mains caps 'wandering'.

Although at the end of the day, if looking for V8 performance, these days you would not even consider a Rover V8 (and probabaly wouldn't for the last 15-20 years)