RR results - thoughts?

[TB Rich]

Just had a scan on this forum and found the following ratio sets for various 197/200 boxes.

Generally it's advised to run in the gear closest to a 1:1 ratio (considering a gearbox is basically a torque multiplier). All of the boxes below have 5th as being the closest to 1.0 ratio and therefore the most appropriate gear to use on the RR. RR's however that measure coastdown losses should in theory even it out.


TL4 003
1 3.181
2 1.947
3 1.482
4 1.205
5 1.026
6 0.872


TL4 024
1 3,18
2 1,95
3 1,48
4 1,21
5 0,97
6 0,81


TL4 031
1 3,36
2 2,10
3 1,51
4 1,21
5 0,97
6 0,81

 

[sideways danny]

you shouldn't be looking at the power figures so much as the fueling on that graph. It's RIIIIIIICH!!!!!! I'd straight off be looking at cam timing there, something quite wrong

 

[Yiannis197]

Chris have you had your car mapped? Who changed the belts for you mate?

 

[lewisflintham]

How do you know what gearbox you've got?

 

[Chrisgti6]

Car isn't mapped and I did the belts (using Renault tools and the Renault technical guide) but I will recheck the timinng sometime in the near future. How far out would it need to be out to give the above results and would it still make that sort of power with incorrect timing?

What sort of AFR should I have been getting?

 

[Raptor6767]

Just had a scan on this forum and found the following ratio sets for various 197/200 boxes.

Generally it's advised to run in the gear closest to a 1:1 ratio (considering a gearbox is basically a torque multiplier). All of the boxes below have 5th as being the closest to 1.0 ratio and therefore the most appropriate gear to use on the RR. RR's however that measure coastdown losses should in theory even it out.

+1 :thumbup1:

 

[sideways danny]

12.5-13:1 from 4k onwards is ideal. so in places you have 25-30% too much fuel (or fuel not being made use of by something wrong)

 

[sideways danny]

mine was done in 4th gear,thought they were all done in 4th:001_unsure:

depends on the type of dyno. 5th is actually the closest to 1:1 gearing for the 197/200. My rollers, because of the type of load brake fitted (ie not computer controlled), if you run in 4th you will get low figures as the engine accelerates too fast and never gets put under load. I always run 6 speed gearboxes in 5th, and 5 speed boxes in 4th (except for a couple of very low power cars that havn't had the power to rev out in 4th so used 3rd). 5th in a 197 has an almost identical terminal speed to a 172 in 4th.

a more modern active/closed loop load dyno like a DD or a superflow can apply load to slow down the power run, and use the amount of load applied in its calculations to keep the figures correct.
Every dyno uses either an rpm pickup on an ht lead, or a manually input ratio of engine to roller rpm. If your limiter is in about the right place on the graph, the ratio is about right

 

[Chrisgti6]

12.5-13:1 from 4k onwards is ideal. so in places you have 25-30% too much fuel (or fuel not being made use of by something wrong)

Thanks Danny, what else could possibly cause fuel to be unburnt? Only reason I ask is that it feels no different to it did before I did the belts so it could be an issue that was already there.

I'm going to check/correct the timing in the next couple of weeks anyway, but if that turns out to be ok - what next? CLIP diagnostics time?

 

[Yiannis197]

what next? CLIP diagnostics time?

Remap time!

 

[nutnutwelshman]

Meg Time???????

 

[Iain 007]

Hammer Time.

 

[Chrisgti6]

Map it or meg it seems to be the fix for everything!

no point mapping it until I fix what's wrong with it!

 

[sideways danny]

Compression test it. It may have been badly remapped, or even have a faulty lambda that's causing long term trim values to be way out. Needs a full diagnostic check over

 

[Chrisgti6]

Compression test it. It may have been badly remapped, or even have a faulty lambda that's causing long term trim values to be way out. Needs a full diagnostic check over

Thanks Danny,

I'll sort the timing first (if it's out) chuck a set of plugs and a clean air filter in then run it again. If it's still bad i'll get it checked out.

Chris

 

[Mi16chris]

Far to rich unless u had a turbo on there lol

Check cam timing and try and fined out on the map on it is stock

 

[Mentalpen]

Isn't there an issue with some belts being fractionally oversized so if set correctly the timing is out and needs to be compensated for?

 

[sideways danny]

Isn't there an issue with some belts being fractionally oversized so if set correctly the timing is out and needs to be compensated for?

if the timing is set correctly, small differences in the belt won't matter. Thats exactly why the F4R is a non key-way'd engine to start with. it would only matter if the pulleys had not been slackened before fitting the new belt (ie the job done wrong)

 

[Mentalpen]

Ok I just recall something to do with a tensioner issue that allowed it to go past the stops, I then wondered if it would cause this sort of issue.

 

[Chrisgti6]

I used the full set of proper tools, and the horseshoe remained I place throughout. The pulleys we're slackened off as they should be (using the tool to hold them) before the new belt was fitted. After fitting and torquing everything up the engine was rotated a few times and the horseshoe slotted back in (it was tight, but had been all the way through. I could get in by hand though.)

I'm fairly certain I did the belt properly, however I will still check the timing is set correctly before doing anything else.

whats the quickest way just to check the timing? Pop the caps out of the end of the cams, set to tdc and put the pin and horseshoe in? If they all go in then it should right shouldn't it?