Twingo Adey's Twingo GT (F4R+T 2.0ltr engine swap)

[bloke]

What's this i hear about 175lb/ft by the way

 

[Adey]

What's this i hear about 175lb/ft by the way

accidental stress testing lol

 

[andybond]

BMEP is literally just specific torque output used to compare engine output of different sizes. If tuners / engine builders are quoting this as directly comparable to cylinder pressure then they're talking out of their posterior - the graphs above have an identical (as near as dammit) BMEP from 2,200 to 3,750 (as the torque is the same) but you can see that the cylinder pressure varies quite a bit over that range. A big BMEP just means that you have a high torque for that capacity.

It was actually one of the guys that worked on the meg 250 map that I quoted that from!

engines fail but they will be failing due to fatigue rather than an instant pressure spike

I think its imperfections in the rod castings that caused the early ones to fail. Weak fuel pump is now causing ringland failures. As you mentioned everything is build to a budget to just exceed the specs

 

[Adey]

accidental stress testing lol

does make me wonder how much more it can take....

 

[andybond]

does make me wonder how much more it can take....

Everything is good once.
Repeatable tests are where its at.

 

[Adey]

Everything is good once.
Repeatable tests are where its at.

indeed. my concern is the rods more than anything. they, though ive not checked them will probably be piss thin. im looking around for upgrades on a budget. would be nice if a renault diesel rod would drop in. i just need to find the specs of mine then try and find a match elsewhere

 

[bloke]

Rods will probably be thicker than you think. There will no doubt be something that will be a straight swap or some Chinese ones off aliexpress, generally around £150 if they do them.

 

[Adey]

Rods will probably be thicker than you think. There will no doubt be something that will be a straight swap or some Chinese ones off aliexpress, generally around £150 if they do them.

thats what im hoping, be nice if they were nice and chunky like a c1J rod but i dont think they will be that big

 

[Adey]

rods have a different part number to the non turbo so that a good sign that they are somewhat stronger. Turbo rods 7701477856 non turbo rods 7701469247

 

[Adey]

Gt D4F(T) / D4F non turbo
Crank 8200156373/ same
Rods x 4 7701477856 / 7701469247
Rod Bolt 7700861631/ same
Conrod bearing set 7701472839 same
Mains 7701472840 same
Piston 7701477824/ 7701475781
Rings 7701477843/ 7701475787

 

[bloke]

From part numbers we found for the 133 rods they looked like toothpicks. When we opened an engine up though this is what we found.


That's next to piston and rod from a 197.

 

[Adey]

not too bad then. dont suppose you could measure one when you get chance. i found these from a derv engine. MEATY! but possibly not needed. @bloke what torque did the 133 run?

 

[Mark Davis]

@Adey - currently watching Clarkson on Dave ripping in a Twingo.

 

[Adey]

asked someone of ebay to measure up a 1.5 derv rod for me....

gudgeon pin 24.08mm approx
end to end 131.80mm approx
big end 46.84mm approx

just need to find the spec on a tce rod too

 

[bloke]

was about 200lb/ft for a year or so and then 220ish when we wound the boost up.

 

[Adey]

Still not had the gasket set turn up yet to see if the tf035 (still unsure if its a 10t or 12t) is a suitable candidate for the twingo but i did give it a little clocking to somewhere close. Everything came apart with ease and moved nicely, if its a goer ill have to knock up a actuator bracket to suit and a downpipe but nothing too taxing.

 

[Adey]

Got this dp on its way to me, made by Protoxide in Italy who seem to be the only company supplying tce Decats. A chap on the twingo fb page had it sat in his garage for a few years. Nice little noise and flow upgrade for the twingo and hopefully i can chop the flange off at a later date for use with the bigger turbo. Was measured up at 2.25inch and from what i gather the stock item is 1.5 to 1.75 inch and obviously has a Cat in there too. Hopefully itll turn up ready for fitting next weekend.

 

[andybond]

Are you not going to need a map tweak once fitted?

 

[Adey]

Map has had the cel/warnings switched off already and the stock cat wasnt really showing as a restriction. To get the most from it yeah a map tweak will be needed but i dont think its going to change anything enough to be a worry. Plenty have fitted decats and theres been no faliures attributed to it, mines pushed a little more, i guess time will tell #boom #blownhg lol

 

[andybond]

You are braver than me! The standard meg can survive a cat removal without a tweak.

A tweaked meg will lean out..