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TR7 - Mild Tuning....

The all purpose forum for any TR7/8 related topics.
Beans
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Postby Beans » 28 May 2010 22:21

To add a little fuel to this discussion ...

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This engine's bottom end and cylinder head is bog standard (so no balancing, porting and polishing).
It’s got a TT “fast roadâ€￾ cam and special (slimmer) valves, SU HS6 with ram pipes inside K&N filters, standard Delco dizzy converted to Lumenition ignition and a Bosch 6 Volt coil.
Also the standard exhaust was ditched for a tubular manifold and a 2" diameter system.

After setting up on a rolling road to get fuelling and ignition sorted properly, it produced 135 bhp.

Has been utterly reliable over the years with very decent fuel economy and good drivability.

<center>Image
<font color="blue"><i>1980 TR7 DHC (my first car, currently being restored)
1981 TR7 FHC Sprint (better known as 't Kreng)</font id="blue">
<b>[url="http://www.tr7beans.blogspot.com/"]<u><b><font size="2"><font color="red">My Weblog</font id="red"></font id="size2"></b></u>[/url]</b></i></center>

nick
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Postby nick » 29 May 2010 00:23

What is the performance penalty for the cat-converter? Mine is still attached. Should I ditch it?

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nick
'79 TR7

Hasbeen
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Postby Hasbeen » 29 May 2010 01:05

Red, you are a master of understatement mate, which is great,
provided others don't take youe advice as gospel. Your few odds &
ends do add up to quite a bit, so to help Hoops, & others who might
be seduced by a $200 Rover V8, I'll list a few.

Radiator, you'll need a bigger one, plus new hoses, etc.

Brake upgrade. Good 7 brakes are marginal for a 2.0L, not good
enough for a V8.

Bell housing, & a flywheel, & clutch, if that V8 is an auto, most
are here in Oz.

Tubular exhausts, & a full tail pipe setup.

Prop shaft, preferably with UJ.

Low ratio diff.

Said quickly it sounds a bit, but if you add the sensible things
like new subframe bushes, & rear sespension bushes, [while the
thing is apart]. Subframe lowering kit realy aught to go in, & a
decent carb, & inlet system while you're at it.

Then this thing's going to go so hard [quick/fast], that you'd
better upgrade the springs & shocks.

The 7v8 is a wonderful car, & worth all the effort to build, but
don't go in with your eyes shut. Most of the conversions I know of
were finished by the second owner. They always cost 3 to 5 times as
much as planned, & take months.

Making a 2.0L go hard enough to be real fun is not too hard, & costs
peanuts, & with the way the price of fuel is going, you can afford
to drive it more often.

Of course, what you really need is one of each.

Hasbeen

Bobbieslandy
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Postby Bobbieslandy » 29 May 2010 01:13

I fell into that trap, i bought a Rover V8 for about £80 off of eBay with the intention of turning my 7 into an 8 for a few hundred quid. Then i saw the price for a bell housing, £300 new, around £100 second hand if you're lucky enough to find one. That alone opened my eyes and put the lid on the idea of a V8. I then went down the sprint route, £0000s of pounds lighter and still got a car up on ramps[:D] i guess if you're going to do anything properly then it's gonna cost ya.

Rob.

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Hasbeen
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Postby Hasbeen » 29 May 2010 02:20

Further to my earlier post, I'll put the mild 2.0L tune into real
world perspective.

I keep my cars in good condition, with everything up to scratch, &
well tuned.

I've has 4 TR7s, with 2 of them bog stock. These 2 were one of each
carb set up, 1 with Zeniths, & 1 with SUs. I found no noticeable
difference in performance between them. My present 7 has over
160,000Km on it, has never had the head off, & has the mild
breathing improvements described earlier.

My local town offeres me the perfect sight to test the tune of my
cars, for no effort. Comming out of town the speed limit goes from
80 to 100Km/H at the very bottom of a long moderate hill. Over this
hill is a 2.5Km long gentle down slope. The hill allows me to test
acceleration & power, & the down slope I use to test brake drag, or
any change in other friction. All well, & they will hold their
speed, in neutral.

With the stock cars, if I hit the hill at 80 both would have to go
back to 4Th to come even near holding that speed. They would loose
a few Km/H. They would accelerate to about 90 if put into third.

With the slightly tuned car, hit the hill at 80 in 5Th, & give it
1/2 throttle, & it will be doing 100Km/H by about half way up the
hill. That is a dramatic performance increase for such a simple
tuning job. As mentioned before, these cars respond much more than
any others I have owned, to small improvements.

If the cars were given a bit of a run up, & hit the hill at 100Km/h,
the tuned car doesn't notice the hill at all. The stock cars if
left in 5Th, would be down to under 80Km/h at the top. If put in
4Th, would still slow to about 95Km/H at the top.

If that townie, with the Fiat X19 is in convoy with me, & I stick it
in 3Rd, & rev the whot not's off it, the stock cars will not drop
any speed, & the honour Triumph will have been upheld, as there is
no way that Fiat can hold it's speed, up that hill.

This, I believe, puts the results of these easy tuning efforts into
a real world perspective.

To add a bit more perspictive, If I floor the 8, anywhere on the
same hill, it will drop back to second, with a chirp of tyres, &
just a little smoke. It will be at drivers licence threatening
speeds, in about 2 seconds, but who needs a car like that, [except
me, that is].

Hasbeen

Hoops
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Postby Hoops » 29 May 2010 13:52

Beans, what kind of torque figure do you get?

I do like the idea of tuning the 2L as i can do bits at a time, where as the V8 i would have to save up all the money and take the car off the road (my only car).

Still cant decide, as i mentioned, i am at the point where after the brakes and suspension i will be spending money on the engine, and at that crossroads [:D]

Cheers

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FI Spyder
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Postby FI Spyder » 29 May 2010 17:58

Doing some mild tuning/optimizing the 8V four is a good idea as you can get some decent performance. Sprint isn't an option here as they were never imported and imported used heads are pretty pricey. You can still get decent TR8's here for $5,000 to $6,000 so if your going that direction it makes more sense. There is even a TR7V8 with spare FI V-8 (bent crank) spare overhauled 4, spare 5 speed, spare TR7 parts car, all for $2,500.


TR7 Spider - 1978 Spifire - 1976 Spitfire - 1988 Tercel 4X4 - Kali on Integra - 1991 Integra
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Beans
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Postby Beans » 29 May 2010 19:39

<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Hoops</i>

Beans, what kind of torque figure do you get? ...<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">
Standard European spec engine produces 161 Nm of torque @ 3700 rpm.
This engine produces that amount of torque @ 2900 rpm.
Maximum torque is 176,5 Nm @4200 rpm

<center>Image
<font color="blue"><i>1980 TR7 DHC (my first car, currently being restored)
1981 TR7 FHC Sprint (better known as 't Kreng)</font id="blue">
<b>[url="http://www.tr7beans.blogspot.com/"]<u><b><font size="2"><font color="red">My Weblog</font id="red"></font id="size2"></b></u>[/url]</b></i></center>

Hoops
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Postby Hoops » 29 May 2010 20:23

Ah cool, thats one reason i was looking at the V8, for the torque as even with my old sprint, low down acceleration was not very good (in 3rd doing 30 for example) where as the V8 will solve this.

So i can roughly get 130BHP out of a tuned 2L 8v, 130Bhp out of a standad 2l 16v and 135Bhp out of the 3.5 V8, all at different price and difficulty [:D]

Thats even more to think about. [:(] [;)]

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Beans
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Postby Beans » 29 May 2010 20:39

Power is not the only factor to get a quick car [;)]

<center>Image
<font color="blue"><i>1980 TR7 DHC (my first car, currently being restored)
1981 TR7 FHC Sprint (better known as 't Kreng)</font id="blue">
<b>[url="http://www.tr7beans.blogspot.com/"]<u><b><font size="2"><font color="red">My Weblog</font id="red"></font id="size2"></b></u>[/url]</b></i></center>

Bobbieslandy
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Postby Bobbieslandy » 29 May 2010 21:41

Have you thought about getting your car Dyno'd and set up properly before changing the engine? something i probably should of done.

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jeffremj
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Postby jeffremj » 30 May 2010 15:04

Back in the mists of time, I uprated an old Triumph Dolomite 1850HL to a 2000HL with fast road cam - I used TR7 bits including the airbox. I put this on an old rolling road and got 90bhp at the wheels which equates to around 120bhp at engine - note that this had the Dolomite exhaust manifold which it just a tube going backwards so add 5bhp to get a TR7 value (125bhp at engine). At around the same time I put a Dolomite Sprint 16V with a mild uprated cam on the same rolling road and got 105bhp at the wheels - 135bhp at engine.
A few years later I put my TR7 16V with fast road cam (but lowered compression - used TR7 pistons) on the same rolling road and got 120bhp (150bhp at engine).
Later on I fitted proper 16V Mahle pistons and got 140 bhp at the engine on a state of the art rolling road.

This means that some rolling roads seek to flatter.

Summary, with existing SU carbs and filter box you will probably only 'really' get around a 10-15 bhp increase in power with a fast road cam.

Note also, that on the same hi-tech rolling road, a TR7 V8 with a Holley carb only got 155 bhp after hours of fettling, so 140bhp from a 16V is not bad. My TR7 V8 gets 165bhp on said rolling road - with standard SUs [;)]

Let's face it, if the likes of Ford and Vauxhall only managed to get 150bhp from 2 litre 16V engines (Astra GTE etc.) with fuel injection during the 1980's, that is probably the maximum we would get for a reasonable outlay!

Hoops
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Postby Hoops » 31 May 2010 10:15

Cheers, will have to try out a rolling road then, see what i am really getting.
Before i make a decision.

[:)]

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jeffremj
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Postby jeffremj » 31 May 2010 11:51

<blockquote id="quote"><font size="1" face="Century Gothic, Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">
Cheers, will have to try out a rolling road then, see what i am really getting.
Before i make a decision.<hr height="1" noshade id="quote"></font id="quote"></blockquote id="quote">A good idea [:)] Try and use a rolling road that gives results that have been compensated for ambient temperature, otherwise you won't get true comparisons from one day to another. Here is my TR8 output showing compensation:

http://www.btinternet.com/~triumph/images/tr8apower.jpg

And here is the video of the power run:

http://www.youtube.com/watch?v=abuC4ce0PMA

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