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GT6_Mark
07-19-2008, 11:24 PM
Building my must do and nice to do lists for my recently acquired '86 280i. One of the nice to dos I am thinking about is a power steering conversion. Anyone done this and able to offer some advice - parts sources/installation tips etc?

It looks like the manual rack on the car is a European Ford part from a Cortina. If so, it seems like a Pinto rack could be a candidate. Does this make sense?

Thanks.

GT6_Mark
07-23-2008, 05:44 PM
Surprised that nobody has any thoughts/ideas/advice to share on on this topic.

kennypinkerton
07-25-2008, 10:03 PM
Why would you want power steering? Is there a lot of effort involved in steering a 280i? Seems like a lot of added weight/complexity and HP robbing PS pump to replace the manual rack if it is sufficient.

GT6_Mark
07-28-2008, 08:15 PM
Some 280is came with power steering. The steering is very heavy at low speeds and not convenient for in-town daily driving. Robbing a few horsepower, when there's plenty enough anyway, is less a concern than having a decent daily driver. A conversion looks to be a piece of cake, there is easy access to the rack and it should be possible to source stock Fords bits to complete the work if I can get a pointer on where to start.

Grady
07-29-2008, 12:51 PM
I spent some time fighting with a vibration in my front end. It turned out to be an invisibly warped set of rims but along the way I discovered how much "feedback" shimmies up to the steering wheel.

In addition to boosting the very slow speed turning - which on my 280 with wider and lower tires is a bear - P/S would dampen out the kick-back from every grove and bump in the road. I'd say a plus.

The trick would be to boost the low speed turning, add some dampening and not boost the mid to fast steering. No idea if that's easy or hard.

Also I can't image a Pinto would make a sophisticated donor unit. IIRC, the un-boosted Pinto was pretty hard to turn - too much for my mother who was looking at a new '73(?) wagon and the one with p/s was typically over-boosted (2 finger steering) at all speeds. If my memory is wrong - apologies to all Pinto owners.

It's low on my list of upgrades but might be interested if it worked. Grady

GT6_Mark
07-29-2008, 02:55 PM
This job is not high on my list of things to do, but it looks like it would be easy. The rack is simple to access and there is plenty of room at the front of the engine for pulley/pump.

Without power steering the low speed load is too much for my wife to handle, and I get less negative feedback from having toys if she gets to play with them as well.

Therefore, if I can source parts, it would move right up the "to do" list.

I'm just stabbing at the Pinto rack being an option. The European Cortina looks to be the basis for much of the TVR's front end and in my mind this translates to Pinto. Certainly, the rack is not very wide.

Someone must know what power rack the factory fitted.........

Grady
07-30-2008, 09:56 AM
Have you asked on the Wedge Forum? https://www.pistonheads.com/gassing/forum.asp?f=12&h=0

Not to belabor the point, but I'd be concerned about over-boosting and loosing the tight steering at speed.

I think the amount of boost is generally not variable. Its been reduced form the over-boost of the '60-'70 to give a more "European feel". But thinking of my newer cars (a Jag and and US SUV) the steering effort is not noticeably affected by speed.

I recall variable effort being an innovation in Corvettes at some time in the not too distant past - maybe in conjunction with an electric pump?

I agree there should be enough space. Maybe a hot-rod shop could give you some guidance on sourcing modern parts. Grady

Grady
07-30-2008, 10:01 AM
One other thought...

I recall that some BL racks (Spitfires or MGBs?) would gunk up and slowly get stiffer and stiffer. Disassembling and cleaning made a huge and better difference.

Again, no idea if that would apply to our racks. Grady

mrtvr
07-30-2008, 07:51 PM
I happen to have one of the US-spec 280is that was fitted at the factorywith PAS (power assisted steering). I also have one with manual steering. I had driven a 1983 Tasmin for 15 years with manual steering and the feel at low speed was directly proportional with the size of tires you had on the car. The wider the tire the harder the steering effort. I found the lightest feel tended to come with a 195 series tire.
My PAS fitted 1987 gives a nice assist at low speed but you barely feel the difference at highway speed. It's definitely not over-assisted by any means.
My 1984 is currently fitted with 195 series tires and is not a handful at all to drive with the manual steering. I guess it's all in what you are accustomed to.

mrtvr
07-30-2008, 07:59 PM
By the way, to answer the question of what power rack was used on the 280i...all power assisted racks after chassis # FBO19415, was a Supra/TVR rack, according to documentation....this would mean any of the series 2 cars in the States were probably fitted with this rack, apparently with some modifications by TVR. But, don't forget, with TVR nothing is cast in stone and cars vary based on what was available at the time of production. Not that many US cars came in with PAS, perhaps only a couple of dozen series 2s. In the home market, prior to the Toyota unit, TVR used both a Ford sourced and Rover sourced PAS unit.

GT6_Mark
07-30-2008, 08:58 PM
Grady, thanks for the idea of checking the current rack for gunk. I want to replace the gaiters/boots anyway, so I might as well pull the rack off while I have it on my lift this weekend.

Marshall, this is intended to be a regular driver for me so I'll give up some feel for convenience. I have a Capri 2.8i PAS pump/bracket along with a bunch of other "collectible" stuff that will get shipped here in a month or so. It will be interesting to see if this works, and the timing also gives me time to hunt down a Supra power rack. My guess is that this will be a project for October.

I'll report back on how this shapes up.

mrtvr
07-31-2008, 02:02 AM
OK Mark, sounds good. I'll look forward to an update from you.

Marshall

Grady
07-31-2008, 11:07 AM
Mark - Let me know if the gunk check does any good.

Marshall - I'm sure you're right about tire size - I think mine are 245s so it's a pair of huge patches to turn at slow speed. Guess it's too late to complain to the seller <grin>.

Grady

TXCoyote
08-12-2008, 08:32 PM
Haven't visited in awhile but I will chime in here. According to Steve Heath you could have either A/C or PAS with a Tasmin in the US. Most owners chose A/C with only a handful of cars coosing PAS.

Marshall is definitely correct in tire size. Bigger is definitely not better. Ideal sie for the front is 195/65 or 195/70. Steering is easier and handling is much better. My car had 205's when I got it and it wouldn't turn at all. With 195's I can almost turn the wheel one handed at a crawl.

Also, with the anemic Ford lump, you don't want to lose any more power than you have to.

mrtvr
08-13-2008, 07:56 AM
Russ,
Regarding the choice of either A/C or PAS here in the states, I believe your statement is correct regarding Series 1 and 1.5 cars with the upright radiator just in front of the engine. However, with the Series 2 cars with the nosecone radiator, things changed with all the extra space available. My 1987 came from the factory with both A/C and PAS. Also, I believe all wedges that came to the States were fitted with A/C. I could be wrong, but I believe that to be the case.

Marshall

GT6_Mark
08-13-2008, 08:40 AM
I have 205/60's, so 195/65 or /70s might be a real alternative option as re-tiring is something that I want to do later this year anyway. I'll get some "temporary" 195s mounted to see if this is the way to go.

Anyway, it looks like I have tracked down all the parts I need to do the power conversion - full front end from someone parting out an '84 Supra here locally and two PS pumps/brackets - one from a Euro Capri 2.8i the other from a Euro Granada 2.8i - in the UK (along with a 5-speed transmission.) This stuff will need overhauling, so the PS project is going to slip down my to-do list. It's looking like November/December time frame.

I'll report back on progress or any other findings.

TXCoyote
08-13-2008, 03:05 PM
Russ,
Regarding the choice of either A/C or PAS here in the states, I believe your statement is correct regarding Series 1 and 1.5 cars with the upright radiator just in front of the engine. However, with the Series 2 cars with the nosecone radiator, things changed with all the extra space available. My 1987 came from the factory with both A/C and PAS. Also, I believe all wedges that came to the States were fitted with A/C. I could be wrong, but I believe that to be the case.

Marshall

You may be right Marshall, I was just quoting from the book. I don't think he differentiated the different series.

As for PAS, it would be nice but I would only do mine if I found a rackk that I could get replacement parts for. Toyota sounds good, I look forward to seeing what Mark comes up with on that.

mrtvr
08-14-2008, 05:35 AM
Some additional information about the steering racks TVR used, in a conversation with Steve Heath recently, he told me the 'Supra' racks were made by a company called Supra, not taken from a Toyota Supra. I don't know if the Supra company is still in existence. As I have a couple of customers very intent on doing a PAS conversion, I am working on a couple of other leads and will report as I find out how they pan out.