[engine_work] Budget 16V Turbo In Laser Green

[peter 20]

100W special hand warmer

[peter 20]

well finally got the car back together with a no #4 on the exhaust and a #2 pulley on the inlet.

 

not much good for a road, it wont idle very well at all needing about 1500rpm to keep it steady, I'm guessing that's down to the low compression and higher lift cams?!

 

Ill try swapping the pulleys round tomorrow!

[petert 587]

Low compression and bigger cam timing is always going to be an issue off boost. Is it really only 7:1? Maybe the standard cams weren't such a bad idea? Have you heard how high the 208 idles?

 

[wicked 103 3 Cars]

Measured the lift on the new cams and the're about 10mm. The standard are about 9mm.

 

Also did a compression check all cylinders are 125psi :0 seems a bit low but the CR could be as low as 7.1:1 sound about right?

 

You cannot derive your static compression from a compression test, unless you know the closing point of your inlet valves very precisely.

 

With longer duration inlet cam, your dynamic compression will drop (this is what you compensate with higher static compression on N/A engines with wild cams).

 

But if your static compression is really 7.1:1, then it's no surprise that i won't idle on wild cams, since won't have much pressure in the cylinders off-boost.

[peter 20]

i don't actually know what the CR is i did a compression check with the the gti6 head and cams, it was 125psi.

 

It now has a s16 head with bigger cams but i haven't checked the compression again.

 

 

The pistons were from an 8v turbo ~8.5:1 then machined so will be slightly less. I'm not sure on the squish? volume but i can imagine the volume in the 16v head is greater than the 8v one. I also used a .2mm thicker head gasket.

 

However it does pull really well higher in the revs. Ill try swapping the pulleys back over tonight and try it again.

 

 

 

The 208, if not all? serious race stuff idles pretty high. I don't use the car that often now so if this setup makes serious power then i can live with it.

[welshpug 1,657]

I guess you are forgetting to hold the throttle open if you are getting consistent results that low, or your gauge is buggered.

[peter 20]

forgetting? i've never held the throttle open when doing a compression test.

My 2.1 mi16 was ~220psi with the throttle shut.

 

 

Anyway i swapped the pulleys round #2 on exhaust #4 on the inlet, and it made zero difference to how it idles, took the car for a spin and it didn't feel much different but i do think it lacks slightly top end now! certainly no increase low down power though!

[peter 20]

boost at 0.5 bar, it hits the limiter in 5th in less than 1/4 of a mile.

[peter 20]

Had the car at york 1/4 mile.

 

It ran a 13.7 @ 102 with only 0.5 bar of boost. I think that's pretty good.

 

It would have ran much better but the paddle clutch is quite snappy so it was difficult not to wheelspin.

On my last run I went on the lane where the drag cars had been, this resulted in the gearbox exploding violently with bits of shrapnel exiting via the radiator.

 

 

A friends 1.7 supercharged fiesta ran a 13.2 @ 110. Still "awaiting rod out of block" that's on a totally standard engine and ecu! Then he noticed it had a boost leak so it was only boosting 7psi instead of 10.

 

All in all quite a good day!

 

I thought BE geaboxs were quite strong?!

[welshpug 1,657]

BE boxes are strong, but not that strong, you are doing THE worst thing you could to one to be fair

[peter 20]

It was a 1.6 box and it did 16 extremly hard launches.

 

Ill try putting the 306 td box back on, the ratios are very long though.

[welshpug 1,657]

It wont be any stronger...

 

the casing is a little stiffer which will help, but internals are much the same design.

[peter 20]

no, but it hasnt got holes in!

 

ml5t, but it wont fit because of the turbo manifold

 

what does pug1off 500hp thing use?

[carlh.1 8]

When he built my engine I think I remember Matt saying he used a quaife gear set and custom made final drive with a plate diff. Don't quote me on that I have slept since then

[peter 20]

oh dear that sounds expensive.

[dcc 855]

its not a constant 500bhp though. I'd suggest you either dull down the launches or just bite the bullet and get a proper gearbox for the engine.

[peter 20]

what would a proper gearbox be??

 

 

dull down the launches, never!!!

[kyepan 291]

check the oil temp in the box, and fit a remote pump and cooler, that sorted out one chaps box issues

[peter 20]

the planet gears had sheared clean in half.

 

Miles recomends changing the diff, as the planet gears are the weak point, this sounds promising! easy fix really.

 

I dont think the gearbox oil would have been hot, the car had been sat for a bit.

 

 

I intend to rev the car flat out then drop the clutch with slicks. Would that be a step too far for even for a decent diff?

[welshpug 1,657]

Not if you fit a decent LSD, but you will break the next weakest link, probably the driveshaft joints.

 

sidestepping the clutch really is not the quickest way off the line with a 205.

[Tom Fenton 1,542]

check the oil temp in the box, and fit a remote pump and cooler, that sorted out one chaps box issues

 

Apparantly it did, but no one ever saw any evidence of it, in my opinion this falls under the "only post first hand verified fact" forum guidelines?

[peter 20]

The driveshaft aren't a major concern, I can use 406 ones.

I would imagine the gearbox is still the weak point.

 

 

I don't side step the clutch, but I was trying to emphasise the fact the drive train will be getting hammered with wide grippy slicks and a paddle clutch.

[NFS 32]

Ive been looking forward to seeing more vid of this, wheeerrrrree arrrreee thheeeyyyyyyyyyyyyyyyyyyyyyyyyyyyy.

[rallyeash 155]

I controlled smooth launch at around 5k keeping a balance between power and grip will be much smoother and quicker than dropping the clutch at 7k.

Realistically whatever tyres you run on a fwd road going 205 your going to get wheel spin so why put so much load on the drivetrain.

 

My 205 is 230hp n/a, does loads of trackdays, the odd hillclimb and plenty of standing starts and I don't have gearbox issues. That's with a plate diff and R888's.

[Tom Fenton 1,542]

It is torque that will cause the problem, and a turbo 16v motor will have a dollop more than your NA motor. Unless you buy proper drag racing slicks such as Hoosiers then you will most likely break traction before you break bits of gearbox, standard planet wheels excluded, as they wear and can cause issues on standard cars. Do not mistake circuit racing slicks with drag racing, the rubber compounds are very different, if you used a set of soft Hoosiers round a circuit you would be lucky to get 5 laps.