Mi16 Back From Mapping And Not Happy

[chris 417 mi 28 2 Cars]

Just got my 205 back from the rolling road at my local tuning company and not pleased with the resut at all

 

heres the results :

 

graph 1

 

graph 2

 

Spec of engine :

 

mi16 rebuilt 2 years ago with standard head refitted

catcams cams & vernier pulleys

Jenvey throttle bodies running on omex 500 ecu

Pugspares 421 exhaust manifold

 

The clutch is brand new, its had bigger injectors fitted from an 1.8 20v turbo engine (249cc i think) and all new leads rotor arm and dizzy cap.

 

Why is the power sooo far down when other members of this site have seen higher gains from less extras

[welshpug 1,627]

links dont work!

 

how does it drive?

[B1ack_Mi16 67]

Can't see the pics, just get redirected to main page of photobucket.

[chris 417 mi 28 2 Cars]

it wont let me add any pictures, for some reason the total space left has gone down to 17k when its usually 250k ish, how can i get some pictures up ?

[brianthemagical 1]

so what was the max bhp then? are you sure your correctly comparing fly and whell figures?

[petert 554]

Use this link:

http://s62.photobucket.com/albums/h95/chrisl417/

 

140hp at the wheels is not too shabby, but I would have expected 145-150hp at the wheels. There's lots of variables of course - compression, ignition timing, cam timing etc. How much time did they spend on the later two?

[Miles 331 1 Cars]

That is bad, From the pic's the head looks like if it's been worked on as the std ports (inlet) are nothing like that, With it set up correctly you should see over 200bhp (Flywheel), Are the injectors OK etc

[pug_ham 242 3 Cars]

it wont let me add any pictures, for some reason the total space left has gone down to 17k when its usually 250k ish, how can i get some pictures up ?

You should have the option of attaching the picture to your account on here when you are creating the topic or making a reply (fadd reply not through quick reply).

 

Graham.

[chris 417 mi 28 2 Cars]

140hp at the wheels is not too shabby, but I would have expected 145-150hp at the wheels. There's lots of variables of course - compression, ignition timing, cam timing etc. How much time did they spend on the later two?

 

The car was on the rollers for approx six hours with the guy telling me he had tried everything to get 200 hp but to not avail

 

That is bad, From the pic's the head looks like if it's been worked on as the std ports (inlet) are nothing like that, With it set up correctly you should see over 200bhp (Flywheel), Are the injectors OK etc

 

The other head in the photobucket album is the old hfh one, the one thats on now was a standard one from matt at QEP. injectors were from ebay and seemed ok, any way to double check though ??

 

 

Really Cant understand why its so down on power, unless its the rollers reading under or possibly due to the temperature in the bay where the dyno is (check ambient temp on the graphs ).

 

You should have the option of attaching the picture to your account on here when you are creating the topic or making a reply (fadd reply not through quick reply).

 

Yeah i have ..but it will only let me add pictures up to 17k not the usual 250 k, only done this since 2 days ago though, could a mod have a look to see if anythings been disabled on my account please

Edited July 12, 2007 by chris 417 mi

[Richie-Van-GTi 70 2 Cars]

injectors came from a low milage audi 1.8 turbo so should be fine, if they were at fault I would of expected the tuners to notice it TBH. Im driving it home this morning but its been a while since I drove it in its previous state so going to be hard to make a comparison to before.

I still maintain, dont worry too much until its seen a different set of rollers as a comparison.

[Sandy 189]

If there was a problem with the injectors, the mapper would have been well aware of it.

[Super Josh 4]

What compression ratio are you running now?

 

 

 

Josh

[kate205gti 4]

hmm that does sound low - did they check cam timing?? does it feel restricted at any rev range? apart from the bhp figure how does the car feel?

 

bhp is great for boasting about down the pub but means feck all really if the car feels and drives fast then who cares

Edited July 12, 2007 by kate205gti

[Richie-Van-GTi 70 2 Cars]

right, just back from driving it about 25-30miles.

There is a serious lack of power low down, to the point I was cogging down on a 1 in 7 incline. Off load the throttle responce is amazing, under load however it feels as though its borking slightly and doesnt want to go, theres no notable difference when it comes on cam either. Its definatley slower than before even though its about 7 bhp up on before, probably due to lack of midrange.

At the moment the trumpets are very short (about 50mm) but when the car first got the bodies the guy at omex in gloucester had tried various trumpets and said these were the best. However at that point the engine wasnt cammed and it made 185bhp which seems a reasonable figure for a rebuilt MI on jenvey's. Since then its dropped power with piper cams and now still down on cat cams. I suspect a poor map but any imput is appreciated as this should be over 200bhp now.

 

the print outs give the afr at around 13's right through

Edited July 12, 2007 by Richie-Van-GTi

[Richie-Van-GTi 70 2 Cars]

What compression ratio are you running now?

Josh

 

 

standard CR.

[Sam 4]

Isn't the spray pattern on a turbo injector wrong for an N/A engine?

[petert 554]

You need to do two things:

 

1. Measure the lift at TDC on the inlet cam

 

2. Check the cranking pressure

 

 

It sounds suspiciously like it's low on compression.

Edited July 12, 2007 by petert

[Richie-Van-GTi 70 2 Cars]

A couple of things I thought may be factors.

standard dizzy igntion, can the omex 500 do ignition and if so whats required as Im guessing it may not be correct for the set up.

Fuel pressure reg, doesnt have a vac pipe on it, I know its probably mapped around this but would there be any benfit from fitting one?

 

I know chris has spoke to Matt at QEP and his advice was the cam timing is out.

[gizzmo 3 1 Cars]

right, just back from driving it about 25-30miles.

There is a serious lack of power low down, to the point I was cogging down on a 1 in 7 incline. Off load the throttle responce is amazing, under load however it feels as though its borking slightly and doesnt want to go, theres no notable difference when it comes on cam either. Its definatley slower than before even though its about 7 bhp up on before, probably due to lack of midrange.

At the moment the trumpets are very short (about 50mm) but when the car first got the bodies the guy at omex in gloucester had tried various trumpets and said these were the best. However at that point the engine wasnt cammed and it made 185bhp which seems a reasonable figure for a rebuilt MI on jenvey's. Since then its dropped power with piper cams and now still down on cat cams. I suspect a poor map but any imput is appreciated as this should be over 200bhp now.

 

the print outs give the afr at around 13's right through

 

i think uv answeared your own question piper cam,cat power dropped each time, im no expert but as an engineer was taught that we must have a datum to work from, my new head with catcams is currently with matt at qep and funds allowing my bottom end will be rebuilt soon so as part of the work he will be setting up the cams which will be the datum the other compenents will be referenced to

[Miles 331 1 Cars]

Yes the OMEX 500 can does the lot, Just get a coil pack which gets shot of that horrid Dizzy thing the ECU has a inbuilt amp as well, but shouldn't the RR sorted the timing out as it's not a long job if the cover's are off

[Richie-Van-GTi 70 2 Cars]

the cams themseleves shouldnt be the issue though, it has to be down to either the map or the cam position, assuming the engine isnt dropping compression which although not checked as yet it doesnt seem likely since it had a fairly recent rebuild and every gasket is new, valves just reseated etc.

[Anthony 1,000]

Cam timing would be my first suspicion - get that wrong and it's very easy to get an engine that's as flat as a pancake and has disappointing power figures.

 

Worth doing a compression check though as others have stated to make sure that's there's nothing really wrong, although I really would have expected the RR operator to have done that as a matter of course if the engine wasn't producing the goods.

[petert 554]

If the inlet cam timing is retarded it will lower the effective compression. Remember that the compression stroke doesn't start until the inlet valve closes. Thus why I said to check both inlet timing and compression.

[brumster 135 1 Cars]

If the inlet cam timing is retarded...

 

Steady on, the inlet cam timing gets sensitive about remarks like that

 

Watching this thread with interest as I'm keen to see what it was, in case I face the same issues

 

I take it you have checked for small rodents trapped in the throttle body trumpets? Goes without saying, really. Sorry, I'll try and offer something constructive next time

[Richie-Van-GTi 70 2 Cars]

the inlet cam and exhaust cam should both of been set to the figures quoted by cat cams and matt at QEP by the company that done the mapping. Im going to try and fudge an extension bar together for my DTi today and check it tonight when chris is home from work. If its not set up as it should be then Chris is taking it straight back to the comapny and demanding it is all redone correctly.