Slow Acceleration

[scarface031]

I finally got my tr7 on the road

It's a five speed

It seems like it is very hard to accelerate though...

Is this just part of the car?

I could be in 1st gear and pedal all the way down, and it just seems like it's trying too hard.

The brakes are not sticking, any suggestions?

Thanks,
Justin P

[tr8coupe]

[:D]simple just drop a big v8 and u will have a nice smile when accelerating [:D]

BMW Z1 ( sold)
Westfield sport carbon (sold)
Eurosport x1/9 turbo (sold)
TR8 coupe
fiat coupe 20vt red wow bargain
Ginetta G27 (sold)
TR7 v8 monster on 245 tyres all round (sold)
TVR VIXEN (sold)
Alfa GTV 3.0 CUP lol(sold)

[FI Spyder]

Shouldn't have too much trouble accelerating. The main problem is the lower rpm range of the 8v motor coupled with a 3.9 diff which make the first gear pretty much a stump puller for this engine ( worse for the 8-1 N/A engines). While more power is always welcome, it's still better than others.

- - -TR7 Spider - - - 1978 Spitfire- - - - 1976 Spitfire - - 1988 Tercel 4X4 - Kali on Integra - 1991 Integra - Yellow TCT

[Hasbeen]

I assume you do have oil in the gearbox & diff, so there is not some mechanical transmission problem.

That means either your engine has very poor power, quite possible if it has had a long hibernation. Plenty of running to polish surface rust off bores, & free up sticky rings usually helps. It is worth shouting the thing a bottle of STP oil treatment, it is great stuff for freeing up sticky rings.

I'd be looking for something making one or more brake drag. They don't have to be sticking on, just not retracting fully to give a bit of extra drag. Our cars really don't have much spare power to overcome even a little extra.

When they haven't been used for a while, the rubbers in the calipers can tend to stick to the pistons when applied. A good hard run through a bit of bumpy twisty stuff should get them right off. Do this & check if the acceleration is better.

Both the hand brake cable & the leaver on the back axle can also stick a bit & generate drag.

Go for a brisk drive, [if possible], then feel the temperature in each wheel to see if one, or one end of the cars brakes are getting hot. If any are, suspect old hoses which degrade inside, making the release of pressure very slow.

Try cracking the bleed nipple on each caliper, & the back one. First notice if there is any residual pressure making any nipple squirt a little fluid. There shouldn't be.

Then try your acceleration, without touching the brake pedal at all, & see if it is better. Sorting I find is really a matter of elimination the possibilities, rather than a flash of genius.

Hasbeen

[Workshop Help]

Yes, the acceleration thingie. For now, let's tastefully ignore our friend, tr8coupe, and his remark, tho it does have a certain validity to it.

Let's review; you indicate in your profile an age of 18, your car is a four cylinder TR7 with about 86 horsepower, and school buses and garbage trucks are out accelerating you from stoplights. Is this about right?

Since Christ was a PFC and Hector was a pup, the TR7 driver has always been unsatisfied with the acceleration of the car. Yes, even the early Federal cars of 1975 and 1976 with at most 92 horsepower fresh off the showroom floor, lagged behind in traffic. Owners sought far and wide here in the U.S.A. for more power and none was to be found.

The other factor was more psychological in that the car sitting still looked like it was going about Warp Factor 7, which meant even with double the power, it still would have seemed to be too slow.

Then there's the whole youthful expectation thing which we all go thru. Without going thru an entire textbook on the topic, let it suffice to say, relax and after a few decades it'll all be better.

Now, as to the car itself. Without knowing what year the car is, or it's actual condition, I will humbly and respectfully suggest a comprehensive tuneup may help. New spark plugs, new ignition cables, clean the distributor cap contacts and rotor tip, install a K&N replacement air filter in the stock air cleaner assembly, balance the air flow and synchronize the carburetors, confirm the ignition timing at the factory recommendations, oil the distributor advance plate and confirm it is not sticking which will prevent the timing mark from advancing, thus holding back the power delivery.

This should keep you busy this weekend.

Mildred Hargis

[scarface031]

I am 19 years old since February

I own a 1976 TR7 Dual SU HS6 in okay condition... For a 76


All the work I have done so far as follows:

<i>Fuel pump replaced</i>
<i>Gas tank restored</i>
<i>Plugs and wires</i>
<i>Oil pan dropped and cleaned</i>
<i>Repaired main harness</i>
<i>Electronic ignition</i>
<i>Rear brake job</i>
<i>Passenger front brake line replaced</i>
<i>Clutch and slave cylinder replaced</i>
<i>Battery</i>
<i>Parking brake fixed and adjusted</i>
<i>Both calipers cleaned and greased (Fixed dragging brakes)</i>
<i>Carbs rebuilt</i>
<i>Timing adjusts 2 degress ATDC at 800 rpm</i>


When I first drove it, the brakes dragged, so I took of the calipers and cleaned everything up. I did not take out the piston.

I can now press the brakes, and they release. I can push the car around easily (I weigh 140lbs)

When I am in first gear, I can put the pedal all the way down, and it seems like it doesn't want to go above 3,000 rpm easily. Shouldn't the tires slip a little?

I'm a pretty relaxed driver, I know its a weak car, but my lawnmower accelerates faster, and its a push!

Thank you everyone for the constructive posts! I really do love this for, I greatly appreciate the time you guys put into this

Thanks,
Justin P

[scarface031]

And how do I oil the distributor advance plate and confirm it is not sticking?

[Workshop Help]

To test for the ignition advance unit functioning, hook up your timing light and observe the timing mark as the engine is accelerated. The timing mark should advance from 2 degrees ATDC at idle to about 14 degrees BTDC at about 3000 RPM, give or take.

If no movement is observed, the advance plate in the distributor is gummed up and sticking in place.

Removal of the distributor advance plate involves removing the two itsey-bitsey screws holding the plate in place. DO NOT DROP THESE SCREWS! Pull the plate out and clean and lubricate the plate so that the plate is freely rotating. Then reinstall without dropping the two itsey-bitsey screws.

I have an article around here someplace in the Forum. Please use the SEARCH function at the top right of your screen to locate it for your perusal.

Mildred Hargis

[scarface031]

Here are the links, just in case anyone is wondering:

http://www.forum.triumphtr7.com/topic.asp?TOPIC_ID=14298&SearchTerms=distributor,advance,plate

http://www.forum.triumphtr7.com/topic.asp?TOPIC_ID=11667&SearchTerms=distributor,advance,plate

[scarface031]

My acceleration is much smoother now that the mechanical advance is working!

I do not have a vacuum advance, I hope that doesn't matter