Ultima 720

Author
Discussion

shaunsmith

Original Poster:

1,229 posts

224 months

Saturday 29th November 2008
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I'm Shortly in the market for a GTR preferably a 720. However, never seen any for sale 2nd hand. Are there any in existance?

Thevet

1,805 posts

240 months

Saturday 29th November 2008
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try speaking to Carlo at www.topgear-cars.co.uk he recently sold a 720 for a mutual acquaintance, and although may not get many 720s to sell, he has experience of buying, owning, running and selling such cars.

Gulf -LS7

1,922 posts

211 months

Saturday 29th November 2008
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Please think about what you want the car for, a 720bhp SBC is going to need a lot of attention/maintenance....

I would seriously look at a LS engine if you want to have that much power. If you are going to use it mainly on the road an ls will be far better.


Wilder

1,509 posts

216 months

Saturday 29th November 2008
quotequote all
Gulf -LS7 said:
Please think about what you want the car for, a 720bhp SBC is going to need a lot of attention/maintenance....

I would seriously look at a LS engine if you want to have that much power. If you are going to use it mainly on the road an ls will be far better.
would this really need more maintanance than any other SBC?. One thing is to regularly check the cam if its a solid roller cam, but any SBC doesnt really need that much to keep it running sweet, and normal servicing can be done yourself.
I believe the 720 is actually a very nice car to drive on the road, but I would ask for the demo to be in the factory car to satisfy yourself that this is what you want.



Edited by Wilder on Saturday 29th November 18:05

suntiger1965

3,546 posts

209 months

Saturday 29th November 2008
quotequote all
Wilder said:
Gulf -LS7 said:
Please think about what you want the car for, a 720bhp SBC is going to need a lot of attention/maintenance....

I would seriously look at a LS engine if you want to have that much power. If you are going to use it mainly on the road an ls will be far better.
would this really need more maintanance than any other SBC?. One thing is to regularly check the cam if its a solid roller cam, but any SBC doesnt really need that much to keep it running sweet, and normal servicing can be done yourself.
I believe the 720 is actually a very nice car to drive on the road, but I would ask for the demo to be in the factory car to satisfy yourself that this is what you want.



Edited by Wilder on Saturday 29th November 18:05
As Kyle said the LS route is certainly the way forward.... there a lot of highly stressed high horsepower stroked 350 chevys out there designed for 250 hp and now with 720hp that wont last that long...(and yes solid lifters need valve adjustment checks regualarly)

The LS engine even in standard form is some engine which will last alot longer and is the the way forward. I went out in the factory demo car which some say is 500hp and some others 530hp and quite frankly unless you are racing or trying to break records was plenty fast enough and possibly sometimes quicker than a 720hp as you could plant the gas pedal without worrying about wheel spin etc etc..

We all dream about being the fastest man on the road but in reality you have still got to be able to drive it on the road. Mine one day will be a ls engine with a couple of turbo's which sounds nutty but with low boost and turbos coming in later, the mpg will be good and power adjustable to driving conditions(ie turn up the boost).... but again a dream and in reality will be a standard LS engine for 1-3 or years before i get bored(knowing me 6 months and the money will run out)...

what ever way you go try the demo car first , you will be very very supprised

dom


738 driver

1,202 posts

200 months

Saturday 29th November 2008
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Hmm, perhaps to keep it at 720hp is more what Kyle is saying.
Even a mere few thousand miles of regular oil/filters/plugs servicing will likely leave you well short of the original output! You need to be really keen and on the ball with the mechanics of an older design, high HP, pushrod engine.
I love engines and have messed for years so SBC is fine for me, for now.......... but if I didn't it would be LS for sure... Maybe the case one day..who knows?
Whats 720 anyway?.... a figure on a dyno sheet! I'll bet there are owners, who if completely honest, would swap a few HP for some other more-desireable quality in their engine combo which better suited their use.
Maybe have a good think about your own, honest requirements,time and resources before you decide.
Good luck.

738 driver

1,202 posts

200 months

Saturday 29th November 2008
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Sorry Dom,
virtually repeated your post.... you're much quicker on the keys than I.
Whats all this about roller adjustment? I'll be hiding from 'BigJoe' if word gets out Im adjusting more than once a year!!!! laugh

Gulf -LS7

1,922 posts

211 months

Saturday 29th November 2008
quotequote all
Wilder said:
Gulf -LS7 said:
Please think about what you want the car for, a 720bhp SBC is going to need a lot of attention/maintenance....

I would seriously look at a LS engine if you want to have that much power. If you are going to use it mainly on the road an ls will be far better.
would this really need more maintanance than any other SBC?. One thing is to regularly check the cam if its a solid roller cam, but any SBC doesnt really need that much to keep it running sweet, and normal servicing can be done yourself.
I believe the 720 is actually a very nice car to drive on the road, but I would ask for the demo to be in the factory car to satisfy yourself that this is what you want.



Edited by Wilder on Saturday 29th November 18:05
I think you would need a rebuild every 5000 miles/12 months imo for it to....... 1. to maintain its 720bhp (i doubt that is achievable from a normally aspirated SBC). 2. be reliable.

The valve springs etc will be very stressed and at a 8000rpm rev limit how long do you realistically think it will last??

I have spent quite a lot of time with Tim Adams{Race engines} and he has told me a SBC running over 500bhp(proper) with a high lift solid cam setup will need a yearly refresh, especially the top end.

738 driver

1,202 posts

200 months

Saturday 29th November 2008
quotequote all
For the majority user Kyle thats probably 100% correct.
But........if you can spare 10mins before and after lay-up periods and are mechanically understanding/interested, that wouldn't have to be the case.
Its just not attractive to most owners.
So you, Dom and I agree, LS for ease....and most other positives!

shaunsmith

Original Poster:

1,229 posts

224 months

Sunday 30th November 2008
quotequote all
Cheers lads & thank you all for your advice. The car won't really be for road use as such it will be for track days predominently including, Ring, Vmax, Fighting Torque & TOTB type events although wont be trailered.

Shaun

suntiger1965

3,546 posts

209 months

Sunday 30th November 2008
quotequote all
shaunsmith said:
Cheers lads & thank you all for your advice. The car won't really be for road use as such it will be for track days predominently including, Ring, Vmax, Fighting Torque & TOTB type events although wont be trailered.

Shaun
well if you are driving to the ring and enjoying the laps, dont even think SBC, just put in the LS engine and enjoy.....cool

dom

Thevet

1,805 posts

240 months

Sunday 30th November 2008
quotequote all
suntiger1965 said:
well if you are driving to the ring and enjoying the laps, dont even think SBC, just put in the LS engine and enjoy.....cool

dom
Why? Been to ring and only reason didn't drive was 3 passengers, SBC didn't miss a beat, would happily drive if was on my own, I'm sure LS and EFI are better, but a well set up SBC isn't all bad, as shown by the simple success of the afternoon's rebuild.....I have missed the noise so much

suntiger1965

3,546 posts

209 months

Sunday 30th November 2008
quotequote all
Thevet said:
suntiger1965 said:
well if you are driving to the ring and enjoying the laps, dont even think SBC, just put in the LS engine and enjoy.....cool

dom
Why? Been to ring and only reason didn't drive was 3 passengers, SBC didn't miss a beat, would happily drive if was on my own, I'm sure LS and EFI are better, but a well set up SBC isn't all bad, as shown by the simple success of the afternoon's rebuild.....I have missed the noise so much
Its all down to personal opion but its up to you. Im sure a SBC with 720 hp wont last too long running to and fro from the ring and racing arround the track. A few years yes but horsepower will be down and rebuilds to be expected...

An almost standard LS7 will last so much longer and not need the constant adjustments of a high milage SBC... If we were talking standard or even mildly tuned HP SBC then that would be different, but 720 hp out of a forty year old engine is a lot to expect to ask of it to last ..

The Ls7 engine in standard form will last for 10's of thousands of miles, maybe 100,000 miles with out problems as it was designed as a road engine in a car weighing far more than an ultima...The SBC was only designed as a road engine producing 250hp and race engines with piston skirts half the size and compressions ratios high, it will only be time im afraid.

If i was building now with these newer generation engines id go the LS route..100%. yes there are plenty of guys running arround the track (Luckyp etc) but the Ls7 wasnt arround then.

dom

Wilder

1,509 posts

216 months

Sunday 30th November 2008
quotequote all
I dont agree with the above statement.
My engine is an SBC, and is a special custom built order from the block up (4 bolt with splayed main caps).
Not all SBC, even high power ones are going to self destruct, as so much depends on the quality and preparation of the engine build, along with the careful matching of the componant parts.
Yes, it will require more checking of course, but if its done with precision and a skilled builder, it should last.

The LS7 requires some serious modifications to get anywhere near 720 bhp, and the cost is simply prohibitive unless your willing to spend around £25K, and that, I believe is maybe why Shaun considered the SBC as an option.



Edited by Wilder on Sunday 30th November 19:05

shaunsmith

Original Poster:

1,229 posts

224 months

Sunday 30th November 2008
quotequote all
I shortly get back my TVR Sagaris which has had the engine completely reworked (over engineered) to eradicate all the issues with the Speed six engine which in standard guise is unreliable with crap standard components then additionally Supercharged & extensively modified throughout the car for track use. I think around tracks & events it would give a 500 bhp Ultima a run for it's money or near perhaps. So what I would like to achieve is the next level of performance or even the next level after that perhaps which is 720 catagory I believe. Preferably, I would not like to turn up at events with a 'nearly' car which I think my Sagaris with 500 bhp would be as what I have seen recently at TOTB & Fighting Torque events etc.

I have a capped budget of around 50K so a new 720 is out my range & will be keeping my Sagaris too as My addiction to TVR's will not go away or diminish but my addiction to Ultima's is also beyond severe now. Idealy one simliar to the black one which has been recently sold by the looks. Maybe i'm slightly crazy but it's oughtright performance I'm after, incredibly long term reliability is secondry I'm prerpared to put up with that as I have a friend / engineer to sort what's necessary at a reasonable cost etc.

Finally, is a 720 achieavable for 50K? Approx how long in mileage would a well maintained 720 SBC last before major work etc? what would a LS7 alone cost with around 700+ bhp? How much or what was the black 720 up for recently.

I dont know much about SBC engines or LS 7 engines either. But there's one thing for certain I would like to have an Ultima with a savage or brutal perfomance way beyond my modded Sagaris...

Shaun

Gulf -LS7

1,922 posts

211 months

Sunday 30th November 2008
quotequote all
Wilder said:
I dont agree with the above statement.
My engine is an SBC, and is a special custom built order from the block up (4 bolt with splayed main caps).
Not all SBC, even high power ones are going to self destruct, as so much depends on the quality and preparation of the engine build, along with the careful matching of the componant parts.
Yes, it will require more checking of course, but if its done with precision and a skilled builder, it should last.

The LS7 requires some serious modifications to get anywhere near 720 bhp, and the cost is simply prohibitive unless your willing to spend around £25K, and that, I believe is maybe why Shaun considered the SBC as an option.



Edited by Wilder on Sunday 30th November 19:05
Im sorry but it will not cost 25k to fit an Ls over a SBC, a LS3 with 600bhp has just been sold on PH for 5.5k thats cheaper than you can build a SBC for with a similiar BHP. It runs efi as standard a dry sump etc etc. If i knew what i do now when i bought my GTR i would never have bought a car with SBC, especially a SBC over 500bhp!!


Wilder

1,509 posts

216 months

Sunday 30th November 2008
quotequote all
There are a number of threads about the LS7 engine and some very knowledgable engine builders on this forum who can give you specifics about the costs, and whats involved to take it over 700bhp.
As a long time TVR devotee, I can tell you no Sagaris will live with a 500 bhp Ultima.

Gulf -LS7

1,922 posts

211 months

Sunday 30th November 2008
quotequote all
shaun pm sent

shaunsmith

Original Poster:

1,229 posts

224 months

Sunday 30th November 2008
quotequote all
Wilder said:
There are a number of threads about the LS7 engine and some very knowledgable engine builders on this forum who can give you specifics about the costs, and whats involved to take it over 700bhp.
As a long time TVR devotee, I can tell you no Sagaris will live with a 500 bhp Ultima.
Cheers, I will check them out. M'mm My Sagaris is not like no other it is Superchaged with around 500 bhp could be a lot more but would probably be undriveable. In comparison 360 bhp in a standard one if your lucky, then yes yor right no other Sagaris would live with a 500 bhp Ultima.

shaunsmith

Original Poster:

1,229 posts

224 months

Sunday 30th November 2008
quotequote all
Gulf -LS7 said:
shaun pm sent
Thank You. However, I'm in Frankfurt on a borrowed laptop & need a 'noose' as i can't watch anymore German TV... Reading the posts you lads have put on my thread has saved my life!!! Seriously, I'm home on Tueday so I will read it then bud.