Just a "what if"
Discussion
I have a 350i convertible and I was wondering what else might need attention if I wanted more power.
So hypothetically, Let's assume I want 300bhp instead of the standard SD1 Rover's 190bhp offering. Ignoring how I achieve this, what would break first and what would need attention? It is currently a standard PAS car with standard Jag LSD and uprated driveshafts, I think from a 400, as one of the originals snapped (Common issue I was told!) Everything else is currently as TVR intended
Obvious questions relating to strength are:
1. Is the chassis up to it?
2. Clutch
3. Gearbox (Rover SD1 so I assume LT77?)
4. Propshaft
5. Diff and driveshafts
6. Brakes
7. Wheels and tyres
It is fun as it is but a little more oomph is always fun!!
So hypothetically, Let's assume I want 300bhp instead of the standard SD1 Rover's 190bhp offering. Ignoring how I achieve this, what would break first and what would need attention? It is currently a standard PAS car with standard Jag LSD and uprated driveshafts, I think from a 400, as one of the originals snapped (Common issue I was told!) Everything else is currently as TVR intended
Obvious questions relating to strength are:
1. Is the chassis up to it?
2. Clutch
3. Gearbox (Rover SD1 so I assume LT77?)
4. Propshaft
5. Diff and driveshafts
6. Brakes
7. Wheels and tyres
It is fun as it is but a little more oomph is always fun!!
Well my 450 SEAC is just shy of 300bhp and my previous 390SE was 250 bhp. There's no obvious differences in the chassis. I did fit uprated clutches to both but not sure they needed it. Standard LT77 gearboxes, 390SE had the larger vented 2 pot Granada brakes which were fantastic. Both have standard Jag LSDs. So in a nut shell apart from maybe front brakes to vented, I don't think any other changes are needed.
KKson said:
Well my 450 SEAC is just shy of 300bhp and my previous 390SE was 250 bhp. There's no obvious differences in the chassis. I did fit uprated clutches to both but not sure they needed it. Standard LT77 gearboxes, 390SE had the larger vented 2 pot Granada brakes which were fantastic. Both have standard Jag LSDs. So in a nut shell apart from maybe front brakes to vented, I don't think any other changes are needed.
That actually sounds quite promising! I have rebuilt various engines and I do love a project. Rover V8 engnes are readily available as are parts both standard and tuned! I fancy a thumping great carburetor too as I find them easier to deal with than fuel injection!! (Old school me!)If I was being cruelly honest, wanting a 'fast' car I'd start with something else. You can bung a big motor into anything but if the whole package isn't up to the task all you have is a selection of compromises.
The Granada vented brakes aren't THAT good, the Princess 4-pots are not that much, if at all better (I started with one and went to the other, including braided lines). Put it this way, my works Connect van stops better.
The LT77 isn't a 'sports' gearbox, the wedge chassis isn't that rigid (and that's ignoring the added flex caused by all the corrosion that WILL be there, unaddressed for 40 years), cumulative play in all the chassis bushes... I'll stop now.
...but don't let that stop you
PS the LSD wasn't 'standard' on a 350i, maybe an option or fitted later.
The Granada vented brakes aren't THAT good, the Princess 4-pots are not that much, if at all better (I started with one and went to the other, including braided lines). Put it this way, my works Connect van stops better.
The LT77 isn't a 'sports' gearbox, the wedge chassis isn't that rigid (and that's ignoring the added flex caused by all the corrosion that WILL be there, unaddressed for 40 years), cumulative play in all the chassis bushes... I'll stop now.
...but don't let that stop you
PS the LSD wasn't 'standard' on a 350i, maybe an option or fitted later.
Wedg1e said:
If I was being cruelly honest, wanting a 'fast' car I'd start with something else. You can bung a big motor into anything but if the whole package isn't up to the task all you have is a selection of compromises.
The Granada vented brakes aren't THAT good, the Princess 4-pots are not that much, if at all better (I started with one and went to the other, including braided lines). Put it this way, my works Connect van stops better.
The LT77 isn't a 'sports' gearbox, the wedge chassis isn't that rigid (and that's ignoring the added flex caused by all the corrosion that WILL be there, unaddressed for 40 years), cumulative play in all the chassis bushes... I'll stop now.
...but don't let that stop you
PS the LSD wasn't 'standard' on a 350i, maybe an option or fitted later.
Ha ha! You don't sound like you are keen on wedges!! The point wouldn't be to get a faster car but to make the wedge a little more lively. I have had much faster cars in the past. The LSD has been there from new. I took it out not long ago to replace seals and I am pretty sure no-one else has ever been there. My brakes are standard but seem pretty good. (try a 1970's Porsche 911 for comparison!). And again for the gearbox, I agree but compared to the Porsche I had it is brilliant. (Road reports of the time said that if you had never driven a Porsche 911 (1978) then you would be forgiven for thinking that the extremely long gear lever isn't actually connected to the gearbox!). I do agree about the chassis though. These tubular chassis are really an unknown quantity. They can look fine but I have seen many articles in the past where bodies are removed and a whole host of horrors are uncovered! But I suspect the truth is that the tubular steel is really massively overdesigned and can tale an awful lot more than the standard cars throw at it, even with corrosion present. If that wasn't the case then there would be stories of chassis' twisting and breaking up on older cars and I have never seen that.The Granada vented brakes aren't THAT good, the Princess 4-pots are not that much, if at all better (I started with one and went to the other, including braided lines). Put it this way, my works Connect van stops better.
The LT77 isn't a 'sports' gearbox, the wedge chassis isn't that rigid (and that's ignoring the added flex caused by all the corrosion that WILL be there, unaddressed for 40 years), cumulative play in all the chassis bushes... I'll stop now.
...but don't let that stop you
PS the LSD wasn't 'standard' on a 350i, maybe an option or fitted later.
I have a YB Cosworth in a Tasmin 200 chipped to 270 BHP and that's a Trailing arm chassis.... so anything is possible!!
It's got the BW T5 gearbox (so can't comment on your gearbox). It has the powerlock Diff. It currently has the smaller drive shafts but TBH I'm surprised these havent let go and I do have a set of the bigger drive shafts that will be fitted shortly. That would be one recommendation.
Trailing Arm gets a bad wrap so I did fit some early upgrades that fit around the bushing to support it and these seemed to have worked as I haven't broken it .... yet!!
It has the AP 4 pot princess calipers and the AP bells and rotors (as fitted to the SEAC). If you push hard enough they do stop the car. I supect the lack of feel is more to do with the lack of servo. But I think you would need to do something about the braking.
One other thing I did was to fit a roll bar. It was initially more of a safety consideration but I think it has helped considerably with chassis flex.
Regards
Steve Evans
It's got the BW T5 gearbox (so can't comment on your gearbox). It has the powerlock Diff. It currently has the smaller drive shafts but TBH I'm surprised these havent let go and I do have a set of the bigger drive shafts that will be fitted shortly. That would be one recommendation.
Trailing Arm gets a bad wrap so I did fit some early upgrades that fit around the bushing to support it and these seemed to have worked as I haven't broken it .... yet!!
It has the AP 4 pot princess calipers and the AP bells and rotors (as fitted to the SEAC). If you push hard enough they do stop the car. I supect the lack of feel is more to do with the lack of servo. But I think you would need to do something about the braking.
One other thing I did was to fit a roll bar. It was initially more of a safety consideration but I think it has helped considerably with chassis flex.
Regards
Steve Evans
keynsham said:
Ha ha! You don't sound like you are keen on wedges!! The point wouldn't be to get a faster car but to make the wedge a little more lively. I have had much faster cars in the past. The LSD has been there from new. I took it out not long ago to replace seals and I am pretty sure no-one else has ever been there. My brakes are standard but seem pretty good. (try a 1970's Porsche 911 for comparison!). And again for the gearbox, I agree but compared to the Porsche I had it is brilliant. (Road reports of the time said that if you had never driven a Porsche 911 (1978) then you would be forgiven for thinking that the extremely long gear lever isn't actually connected to the gearbox!). I do agree about the chassis though. These tubular chassis are really an unknown quantity. They can look fine but I have seen many articles in the past where bodies are removed and a whole host of horrors are uncovered! But I suspect the truth is that the tubular steel is really massively overdesigned and can tale an awful lot more than the standard cars throw at it, even with corrosion present. If that wasn't the case then there would be stories of chassis' twisting and breaking up on older cars and I have never seen that.
I appreciate my wedge for what it is, but I don't think of it as a fast car. I just like owning something few other people have or will. If I want to go quickly I get on a bike.I've done several wedge chassis repairs, the worst of which had no coupling between the shell and chassis along both sills. Even Oliver Winterbottom acknowledged that the shell was an integral part of the overall rigidity. If you go back to the Grantura the chassis was glassed-in to the shell!
The wedge shell is effectively rubber-mounted which is a compromise in itself, not helped by the rubber perishing and the sill plates corroding. Often you can see the door shutlines alter as you jack the car up, so something is flexing. Oliver W. said they only added one more diagonal brace to the chassis backbone for the DHC.
I'd be surprised if there weren't more modern discs and calipers you could use but it needs someone to sit and try things - it may be that Ford maintained the relative distance from caliper mounting to disc centreline so calipers from something more recent might work, but I'd guess that the really beefy stuff has mounting holes spaced much further apart (and may well need larger rims to fit under). As Steve also hints, a better servo could improve matters.
I went for the supposed upgrade to the AP 4-pots and am honestly not convinced there's much if any improvement; the pad surface area is smaller and it overhangs the disc, losing even more contact - the calipers weigh about the same too so no benefit there. But 'everyone says' so maybe it's just me.
Not sure how hard you have to be trying to shear the driveshafts mind. My mate has a 500 Griffith with substantially more power than my 390 (it'll spin the wheels in 3rd when you're already doing 60) and the half-shafts are no chunkier than the wedges'.
Edited by Wedg1e on Tuesday 4th June 17:57
SEvans said:
One other thing I did was to fit a roll bar. It was initially more of a safety consideration but I think it has helped considerably with chassis flex.
If you are interested, there are a number of very detailed threads about roll bars maybe 10-15 years ago including some dos and don'ts. Also, the windshield header is not at all structural.Wedg1e said:
I appreciate my wedge for what it is, but I don't think of it as a fast car. I just like owning something few other people have or will. If I want to go quickly I get on a bike.
I've done several wedge chassis repairs, the worst of which had no coupling between the shell and chassis along both sills. Even Oliver Winterbottom acknowledged that the shell was an integral part of the overall rigidity. If you go back to the Grantura the chassis was glassed-in to the shell!
The wedge shell is effectively rubber-mounted which is a compromise in itself, not helped by the rubber perishing and the sill plates corroding. Often you can see the door shutlines alter as you jack the car up, so something is flexing. Oliver W. said they only added one more diagonal brace to the chassis backbone for the DHC.
I'd be surprised if there weren't more modern discs and calipers you could use but it needs someone to sit and try things - it may be that Ford maintained the relative distance from caliper mounting to disc centreline so calipers from something more recent might work, but I'd guess that the really beefy stuff has mounting holes spaced much further apart (and may well need larger rims to fit under). As Steve also hints, a better servo could improve matters.
I went for the supposed upgrade to the AP 4-pots and am honestly not convinced there's much if any improvement; the pad surface area is smaller and it overhangs the disc, losing even more contact - the calipers weigh about the same too so no benefit there. But 'everyone says' so maybe it's just me.
Not sure how hard you have to be trying to shear the driveshafts mind. My mate has a 500 Griffith with substantially more power than my 390 (it'll spin the wheels in 3rd when you're already doing 60) and the half-shafts are no chunkier than the wedges'.
It was my brother in law who used to own the car who broke a driveshaft. one of the ends where the UJ fits actually snapped off. He told be it was a weak point on the original 350i and the fix was to fit later beefier 400 ones which he did. I had an interesting discussion about brakes with a friend yesterday too which went like this....I've done several wedge chassis repairs, the worst of which had no coupling between the shell and chassis along both sills. Even Oliver Winterbottom acknowledged that the shell was an integral part of the overall rigidity. If you go back to the Grantura the chassis was glassed-in to the shell!
The wedge shell is effectively rubber-mounted which is a compromise in itself, not helped by the rubber perishing and the sill plates corroding. Often you can see the door shutlines alter as you jack the car up, so something is flexing. Oliver W. said they only added one more diagonal brace to the chassis backbone for the DHC.
I'd be surprised if there weren't more modern discs and calipers you could use but it needs someone to sit and try things - it may be that Ford maintained the relative distance from caliper mounting to disc centreline so calipers from something more recent might work, but I'd guess that the really beefy stuff has mounting holes spaced much further apart (and may well need larger rims to fit under). As Steve also hints, a better servo could improve matters.
I went for the supposed upgrade to the AP 4-pots and am honestly not convinced there's much if any improvement; the pad surface area is smaller and it overhangs the disc, losing even more contact - the calipers weigh about the same too so no benefit there. But 'everyone says' so maybe it's just me.
Not sure how hard you have to be trying to shear the driveshafts mind. My mate has a 500 Griffith with substantially more power than my 390 (it'll spin the wheels in 3rd when you're already doing 60) and the half-shafts are no chunkier than the wedges'.
Edited by Wedg1e on Tuesday 4th June 17:57
Brakes stop your car and are nothing to do with acceleration. So assuming you haven't added mass to your car, then at any given speed, the braking force to stop is the same regardless of whether you have 100bhp or 1000bhp.It doesn't matter how fast you accelerate, as at the point you apply the brakes, there is just a mass at a given speed that requires a braking force to stop it. The only reason to upgrade the brakes on a car that has more power is if you are actually going to drive it faster than it would go with standard power. Considering we have speed limits which the standard brakes are more than capable of dealing with, unless you do track days, the additional braking ability of an upgrade is not necessary for a road car. Unless of course your standard brakes are rubbish to begin with. A certain MG Midget I used to own would be in that category!! Just a though!!
keynsham said:
It was my brother in law who used to own the car who broke a driveshaft. one of the ends where the UJ fits actually snapped off. He told be it was a weak point on the original 350i and the fix was to fit later beefier 400 ones which he did. I had an interesting discussion about brakes with a friend yesterday too which went like this....
Brakes stop your car and are nothing to do with acceleration. So assuming you haven't added mass to your car, then at any given speed, the braking force to stop is the same regardless of whether you have 100bhp or 1000bhp.It doesn't matter how fast you accelerate, as at the point you apply the brakes, there is just a mass at a given speed that requires a braking force to stop it. The only reason to upgrade the brakes on a car that has more power is if you are actually going to drive it faster than it would go with standard power. Considering we have speed limits which the standard brakes are more than capable of dealing with, unless you do track days, the additional braking ability of an upgrade is not necessary for a road car. Unless of course your standard brakes are rubbish to begin with. A certain MG Midget I used to own would be in that category!! Just a though!!
One could argue that the more powerful car regains lost speed sooner so that the frequency with which you need to brake outweighs the time the brakes have to cool... so 'uprated' does not necessarily mean more stopping power per se, but better 'recovery'. Hence vented discs.Brakes stop your car and are nothing to do with acceleration. So assuming you haven't added mass to your car, then at any given speed, the braking force to stop is the same regardless of whether you have 100bhp or 1000bhp.It doesn't matter how fast you accelerate, as at the point you apply the brakes, there is just a mass at a given speed that requires a braking force to stop it. The only reason to upgrade the brakes on a car that has more power is if you are actually going to drive it faster than it would go with standard power. Considering we have speed limits which the standard brakes are more than capable of dealing with, unless you do track days, the additional braking ability of an upgrade is not necessary for a road car. Unless of course your standard brakes are rubbish to begin with. A certain MG Midget I used to own would be in that category!! Just a though!!
The wedge halfshafts are fabricated rather than forged (as in, say, the Jaguar setup) so poor weld penetration or any of a myriad of other defects could lead to a breakage, I wouldn't say it was a weak point of the vehicle. TVR did subcontract quite a few parts and were at the mercy of the QA procedures of those companies... chocolate cam followers, anyone?
Wedg1e said:
keynsham said:
It was my brother in law who used to own the car who broke a driveshaft. one of the ends where the UJ fits actually snapped off. He told be it was a weak point on the original 350i and the fix was to fit later beefier 400 ones which he did. I had an interesting discussion about brakes with a friend yesterday too which went like this....
Brakes stop your car and are nothing to do with acceleration. So assuming you haven't added mass to your car, then at any given speed, the braking force to stop is the same regardless of whether you have 100bhp or 1000bhp.It doesn't matter how fast you accelerate, as at the point you apply the brakes, there is just a mass at a given speed that requires a braking force to stop it. The only reason to upgrade the brakes on a car that has more power is if you are actually going to drive it faster than it would go with standard power. Considering we have speed limits which the standard brakes are more than capable of dealing with, unless you do track days, the additional braking ability of an upgrade is not necessary for a road car. Unless of course your standard brakes are rubbish to begin with. A certain MG Midget I used to own would be in that category!! Just a though!!
One could argue that the more powerful car regains lost speed sooner so that the frequency with which you need to brake outweighs the time the brakes have to cool... so 'uprated' does not necessarily mean more stopping power per se, but better 'recovery'. Hence vented discs.Brakes stop your car and are nothing to do with acceleration. So assuming you haven't added mass to your car, then at any given speed, the braking force to stop is the same regardless of whether you have 100bhp or 1000bhp.It doesn't matter how fast you accelerate, as at the point you apply the brakes, there is just a mass at a given speed that requires a braking force to stop it. The only reason to upgrade the brakes on a car that has more power is if you are actually going to drive it faster than it would go with standard power. Considering we have speed limits which the standard brakes are more than capable of dealing with, unless you do track days, the additional braking ability of an upgrade is not necessary for a road car. Unless of course your standard brakes are rubbish to begin with. A certain MG Midget I used to own would be in that category!! Just a though!!
The wedge halfshafts are fabricated rather than forged (as in, say, the Jaguar setup) so poor weld penetration or any of a myriad of other defects could lead to a breakage, I wouldn't say it was a weak point of the vehicle. TVR did subcontract quite a few parts and were at the mercy of the QA procedures of those companies... chocolate cam followers, anyone?
As an A frame car it is already years away from the O.W. wrong way around front end and rear trailing arms AND it has moved on to struggling to support the C.S. evolution of a huge front ARB and heavy springs with a poor differential lower mount . My reality is that I have a SEAC chassis/interior with a 2.8 in, with a body dropping through poor chassis/body supports (due it it's weight). As a 2.8 (read NO BHP) the rear ends flexes on the two lower mount bolts (there are pictures on here of that failing) and the car takes a 'set' on the suspension after you lean on a rear corner, if you turn right and right the car 'feels' stable, but R/L and right again twists and reacts poorly to steering input. The 450 I used to look after had these traits with an abundance of silly forward motion, which is seriously good fun BUT not fast. (I won't be selling my 280DH any time soon, once the chassis out riggers and body mounts are fixed it will be fun again). IMHO, do nothing, go out and have fun with it as it is. A@
Working from the back of the list - tyres first. Tyre choice makes a hell of a difference with traction and feel.
You might want to go to 9Jx16 wheels for the rear and 245 tyres to get that power down onto the road.
Brakes - change up to mintex pads all round. 4-pot princess are fine on the front. The rears don't do a lot, just keeps the rear getting in front.
To keep them fettled, use them hard at least once a day.
Go around the chassis with a hammer, the pipes should "ring" and not sound "dull" which is a sign they have corroded from the inside.
You might want to go to 9Jx16 wheels for the rear and 245 tyres to get that power down onto the road.
Brakes - change up to mintex pads all round. 4-pot princess are fine on the front. The rears don't do a lot, just keeps the rear getting in front.
To keep them fettled, use them hard at least once a day.
Go around the chassis with a hammer, the pipes should "ring" and not sound "dull" which is a sign they have corroded from the inside.
I have the story of the "Gredge"...5.0 HC Griffith engine in a 350i Wedge that Chris, aka Jack Valiant built, I may be able to share it but all rights belong to Chris, if you are a member of the TVR Wedge owners UK on FB then it is in the file section, very in-depth ...I will see if I can post it in a documented form....need to ask permission...
“The Gredge is a joining of souls of the power of the 500 Griffith and the presence and sound of the Wedge!” ...By Chris aka Jack Valiant
“The Gredge is a joining of souls of the power of the 500 Griffith and the presence and sound of the Wedge!” ...By Chris aka Jack Valiant
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