Tuscan LS1 Convertions
Discussion
Have Have recently started to convert Tuscan speed six to LS
first thing you find is the exhaust ports come out directly onto chassis rail
these rails are 22 inches apart, any LS engine is 21 inches wide leaving half
an inch a side for exhausts and clearances
Have looked at the low res pics people have posted LS Engines they seam very High in
the chassis
Would anybody like to comment on just how much the crank centre has been lifted
to get these engines "in"
we can all put smoothie covers over offending mal practises
first thing you find is the exhaust ports come out directly onto chassis rail
these rails are 22 inches apart, any LS engine is 21 inches wide leaving half
an inch a side for exhausts and clearances
Have looked at the low res pics people have posted LS Engines they seam very High in
the chassis
Would anybody like to comment on just how much the crank centre has been lifted
to get these engines "in"
we can all put smoothie covers over offending mal practises
As stated before... junk the standard manifolds.
Fit these and there is plenty of clearance.
As for engine height... depends very much on which sump you have as most wet sumps are about 8 inches deep. That will determine the height of the engine. In addition, the Speed Six lump - and I use the term advisedly - is very deep and it's top is located just below the wipers.
The LS T350C goes for its MOT on Monday. The next Tuscan is almost ready for the engine to drop in. I spent some time preparing it this week. No chassis mods what so ever on these cars.
Fit these and there is plenty of clearance.
As for engine height... depends very much on which sump you have as most wet sumps are about 8 inches deep. That will determine the height of the engine. In addition, the Speed Six lump - and I use the term advisedly - is very deep and it's top is located just below the wipers.
The LS T350C goes for its MOT on Monday. The next Tuscan is almost ready for the engine to drop in. I spent some time preparing it this week. No chassis mods what so ever on these cars.
Edited by shpub on Saturday 11th September 17:56
Am i missing something here almost every American speed shop sells several LS sump pans (oil pan)
since you only have the anti roll bar to work around this does not justify lifting the engine
The speed six is an inline double overhead cam engine even thow the top of the cam cover is just below the wipers, the main mass of the unit, the crank, flywheel and clutch are very low in the chassis
The LS engine is a V8 pushrod engine most of the mass is around the crank axis
It is normal automotive engineering practise to keep this as low as possible the usual factor that determines the crank height in a chassis installation is the diameter of the flywheel and clutch pack
to suggest an installation would have critical dimensions worked around a pickup truck oil pan is a little worrying
For the sake of all our sanity would people please note, a sump pan from a sports car not a truck is required when doing these conversions
Can i suggest you could get together and form the "Mile High Club"
since you only have the anti roll bar to work around this does not justify lifting the engine
The speed six is an inline double overhead cam engine even thow the top of the cam cover is just below the wipers, the main mass of the unit, the crank, flywheel and clutch are very low in the chassis
The LS engine is a V8 pushrod engine most of the mass is around the crank axis
It is normal automotive engineering practise to keep this as low as possible the usual factor that determines the crank height in a chassis installation is the diameter of the flywheel and clutch pack
to suggest an installation would have critical dimensions worked around a pickup truck oil pan is a little worrying
For the sake of all our sanity would people please note, a sump pan from a sports car not a truck is required when doing these conversions
Can i suggest you could get together and form the "Mile High Club"
As you said yourself, what you are doing for your conversion is not commercially viable and you have the advantage of access to the right facilities which many would be envious of...
In the end there is a choice:
Mount the engine where the Speed Six sits and not have to worry about the cost and effort in cutting chassis rails, modifying bodies and all the other issues caused by the fact that the Tuscan chassis was not designed for a V8... or
Mount the engine as low as possible and have to get a shallower sump (which may or may not cause starvation issues), remove the body, mod the chassis and body etc etc etc.
As I understand it, you went for the chassis mod because you didn't want to compromise the headers on your engine. The headers are nothing special and are in fact the same as I used on my Cerbera. They came with the engine pull. I had the same challenge but I felt that modding the headers was a more cost effective way forward than modding the chassis. I have had several Ls 'experts' comment that my modded headers severely restrict the engine but when I point out that the car dyno'd 50 bhp more than the GM spec so where exactly was the restriction... the conversation goes quiet. Since then I have worked on the headers that I showed in the picture and they provide really good clearance and have better breathing.
As for weights etc... for a start the LS is about 45-50kg lighter than the speed six. It doesn't have the additional weight of the throttle bodies, OHCs etc that the speed six has. These are right at the top of the engine which makes it very top heavy. Mount the engine where the speed six was and compared to the original design, the LS is 45kg lighter and is less top heavy which means that everything is still in your favour. Yes it would be better to mount the engine lower but and this is where the decision making diverts, are the advantages worth the many thousands of pounds needed to change the body and chassis to do it? For most people, the answer is simply no.
While this may not be as ideal as getting the engine a bit lower, it is more practical and this translates into less effort and cost. It doesn't mean that it is fundamentally wrong. It is just a different, more pragmatic implementation. The Speed Six is a very top heavy engine, especially compared to the LS.
Corvette actually made a shallow sump for the LS - I have one in my Cerbera - but at 24 inches wide it doesn't fit. I had to modify it to squeeze it in. It came with the engine and it was cheaper to mod than to get a new one. It was reported to suffer from oil starvation issues when the engines were tuned up and the cars thrashed on the track. I did add some more traps to help address this and the oil pressure has been solid from day 1. One of the alleged reasons why the cars went to fly by wire throttle was to enable the ECU to limit the throttle and power when the oil pressure went low when cornering. Corvette then changed to a deeper more traditional sump design which solved the problem. To get anything better really means switching to a dry sump design which again increases the costs dramatically.
In the end of the day, any conversion is a set of compromises. It would probably cost about £8 to 10K including the time and effort to do the mods to get the engine where you have put it. If the decision to do it was done to improve the handling, I reckon that investing half that into a set of Ohlins would bring a lot more improvements than that gained by sitting the engine a bit lower.
In the end there is a choice:
Mount the engine where the Speed Six sits and not have to worry about the cost and effort in cutting chassis rails, modifying bodies and all the other issues caused by the fact that the Tuscan chassis was not designed for a V8... or
Mount the engine as low as possible and have to get a shallower sump (which may or may not cause starvation issues), remove the body, mod the chassis and body etc etc etc.
As I understand it, you went for the chassis mod because you didn't want to compromise the headers on your engine. The headers are nothing special and are in fact the same as I used on my Cerbera. They came with the engine pull. I had the same challenge but I felt that modding the headers was a more cost effective way forward than modding the chassis. I have had several Ls 'experts' comment that my modded headers severely restrict the engine but when I point out that the car dyno'd 50 bhp more than the GM spec so where exactly was the restriction... the conversation goes quiet. Since then I have worked on the headers that I showed in the picture and they provide really good clearance and have better breathing.
As for weights etc... for a start the LS is about 45-50kg lighter than the speed six. It doesn't have the additional weight of the throttle bodies, OHCs etc that the speed six has. These are right at the top of the engine which makes it very top heavy. Mount the engine where the speed six was and compared to the original design, the LS is 45kg lighter and is less top heavy which means that everything is still in your favour. Yes it would be better to mount the engine lower but and this is where the decision making diverts, are the advantages worth the many thousands of pounds needed to change the body and chassis to do it? For most people, the answer is simply no.
While this may not be as ideal as getting the engine a bit lower, it is more practical and this translates into less effort and cost. It doesn't mean that it is fundamentally wrong. It is just a different, more pragmatic implementation. The Speed Six is a very top heavy engine, especially compared to the LS.
Corvette actually made a shallow sump for the LS - I have one in my Cerbera - but at 24 inches wide it doesn't fit. I had to modify it to squeeze it in. It came with the engine and it was cheaper to mod than to get a new one. It was reported to suffer from oil starvation issues when the engines were tuned up and the cars thrashed on the track. I did add some more traps to help address this and the oil pressure has been solid from day 1. One of the alleged reasons why the cars went to fly by wire throttle was to enable the ECU to limit the throttle and power when the oil pressure went low when cornering. Corvette then changed to a deeper more traditional sump design which solved the problem. To get anything better really means switching to a dry sump design which again increases the costs dramatically.
In the end of the day, any conversion is a set of compromises. It would probably cost about £8 to 10K including the time and effort to do the mods to get the engine where you have put it. If the decision to do it was done to improve the handling, I reckon that investing half that into a set of Ohlins would bring a lot more improvements than that gained by sitting the engine a bit lower.
I have to ask what BHP should you expect from the conversion,my 4.3 lt upgrade produces 439 at the flywheel and im wondering if i went the wrong way.
I have to say the conversion has made a world of difference to the engine it no longer sounds tortured its very smoothe right through the rev range.
it started life as a Tuscan 2 S I really cannot see these cars with more than 460 bhp they would be leathal if they are not already
Simon
I have to say the conversion has made a world of difference to the engine it no longer sounds tortured its very smoothe right through the rev range.
it started life as a Tuscan 2 S I really cannot see these cars with more than 460 bhp they would be leathal if they are not already
Simon
Nice to see pics not just talk
Still think the fitting of an LS just as much of an unknown as the speed six is,
would like to see pics of stuff like engine mounts, exhaust manifolds fitted
As we get further into this subject It just seams to get more complected and the
Word "Compromises" does not really inspire much confidence
I take it to mean "quality against cost," not sure this is really the way to go
seams strange the Tuscan as been out Ten years and very few have been converted to LS
I have had cars with LS engines in and spoken to both the UK recognised specialist
Both seam to doubt the simple cam change to 500HP
Monkfish performance and Knight racing
Also how can one conversion cost twice the price of the other, doesn't add up
Still think the fitting of an LS just as much of an unknown as the speed six is,
would like to see pics of stuff like engine mounts, exhaust manifolds fitted
As we get further into this subject It just seams to get more complected and the
Word "Compromises" does not really inspire much confidence
I take it to mean "quality against cost," not sure this is really the way to go
seams strange the Tuscan as been out Ten years and very few have been converted to LS
I have had cars with LS engines in and spoken to both the UK recognised specialist
Both seam to doubt the simple cam change to 500HP
Monkfish performance and Knight racing
Also how can one conversion cost twice the price of the other, doesn't add up
a simple cam change and that would make it a 500 bhp install.
Ye that looks simple
http://www.summitracing.com/parts/TFS-K306-500-460...
![](http://thumbsnap.com/sc/TzGOAvR8.jpg[/img]</a> <a href="http://thumbsnap.com/2cOM7NUZ" Target="_blank">[img]http://thumbsnap.com/sc/2cOM7NUZ.jpg)
I think 440 HP is about max for stock valve train
To replace a Speed Six with an engine that is has push-rods and valve springs that are not strong enough for the cam lift/duration/duty is a waste of time
Is there something about keeping the TVR unreliability
Ye that looks simple
http://www.summitracing.com/parts/TFS-K306-500-460...
I think 440 HP is about max for stock valve train
To replace a Speed Six with an engine that is has push-rods and valve springs that are not strong enough for the cam lift/duration/duty is a waste of time
Is there something about keeping the TVR unreliability
shpub said:
I would expect around the 450-475+ with similar torque figures. An extra 50 bhp can be obtained through a simple cam change and that would make it a 500 bhp install. We can detune the engine if you don't want the power... 
The 500 HP cam swap is quite a claim,On top of the engine components you have named i would expect the LS1 rocker-arms and the studs that retain them to be very close to there limit
Not to mention such things as the radiator, T5 gearbox, clutch, drive shafts, and exhausts
475 HP seams to be the point were the Chevy tuner's go up on size with these ancillary items, going from 2 1/2 inch to 3 inch pipes on a vette is one thing, but doing it in TVR is another, the same would apply to the radiator, its a
massive job to get a bigger rad in the front of a TVR (an aftermarket 500hp rad would be topical be 33" x 18") add to that the clutch, gearbox box, diff and drive shaft issues i would say the cost of going from installing a 440hp
LS to a 500hp LS is around Double
all of this is well documented on any of the Corvette camaro and LS forums the only difference being a camaro chassis is 32 inch's wide in the engine bay and a Tuscan is 22 this adds to the time and costs
I think the min costs of the parts for a 450hp LS swap are
Engine 4000
Sump 2000
gearbox 2000
Clutch 1000
starter and alt 400
Ecu 1000
wiring 1000
exhaust 1000
add something for engine mounts, gearbox cross-member, hoses, air filter, fuel pump, reg, filter and all the odd and sods, your near 14K for the basic parts
I,ve Just got a feeling we are going to see 500hp LS Tuscans showing up, running 400hp cooling systems and 1 3/4" exhaust, then slagging off an engine that is in fact a true masterpiece
Grant
Errr For a start... I am not using an LS1 but an LS3 derived engine... My car has an LS1 but I don't use them in the conversions.
I don't need to spend thousands on sumps, ECU, wiring etc because I have developed a way of reusing them. That means I don't have to spend thousands replacing parts that the car already has. That allows money to be spent elsewhere on the transmission if the owner thinks it is needed. With a 500 bhp build, I would strongly recommend it but some people don't drive their cars aggressively and want 500 bhp for the pub. Equally I suggest waiting until they have driven the car with the lower power before seeing if they want to go more. I also point out the potential risks, the solutions and costs and let the customer participate in the decision making.
As for rads... If more cooling is needed then it can be added by simply replacing the rad for a more efficient one. My 600 bhp supercharged wedge runs cool on such a rad. Its the same size as the original, which just happens to be the same dimensions as the Tuscan rad. Same physical size - just about 20% more cooling capacity.
The SP6 conversions do cost a little more than a Cerb AJP but by being smart and not simply throwing money at it and replacing everything, the costs can be kept down to a minimum.
I don't need to spend thousands on sumps, ECU, wiring etc because I have developed a way of reusing them. That means I don't have to spend thousands replacing parts that the car already has. That allows money to be spent elsewhere on the transmission if the owner thinks it is needed. With a 500 bhp build, I would strongly recommend it but some people don't drive their cars aggressively and want 500 bhp for the pub. Equally I suggest waiting until they have driven the car with the lower power before seeing if they want to go more. I also point out the potential risks, the solutions and costs and let the customer participate in the decision making.
As for rads... If more cooling is needed then it can be added by simply replacing the rad for a more efficient one. My 600 bhp supercharged wedge runs cool on such a rad. Its the same size as the original, which just happens to be the same dimensions as the Tuscan rad. Same physical size - just about 20% more cooling capacity.
The SP6 conversions do cost a little more than a Cerb AJP but by being smart and not simply throwing money at it and replacing everything, the costs can be kept down to a minimum.
Edited by shpub on Tuesday 4th January 08:52
@shpub
hi there,
im starting an tvr tuscan ls3 conversion next month, have to wait for the engine.
the headers u posted before are they custom made, or can i order them somewhere?
i would like to order a pair of these headers, so i dont have to bother with building custom headers for this project.
regards jbdexter
hi there,
im starting an tvr tuscan ls3 conversion next month, have to wait for the engine.
the headers u posted before are they custom made, or can i order them somewhere?
i would like to order a pair of these headers, so i dont have to bother with building custom headers for this project.
regards jbdexter
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