Timing issue?

[speedysmartypants 0]

ive jus done my headgasket and i removed my spacer plate in exchange for a standard gasket. car is a bit lumpy and theres no power when you put your foot down. could this be the ignition timing as it was mapped with the lower compression? ive checked the cam timing, plugs and leads.

thanks for your time

chris

[CorradoVR6-Turbo 0]

So your running the same set up besides the spacer gasket?

[speedysmartypants 0]

yep. ive checked everything and the ignition timing is the only thing i can think of

[CorradoVR6-Turbo 0]

The timming is fixed regardless of coilpack or dizy,have you 100% got the cam timing correct? are you dizy or coilpack?

 

The spacer plate should not affect the running low down,but higher up the mapping will probably differ than before,does it idle ok?

 

Why have you taken the spacer plate out?

[speedysmartypants 0]

my car is a dizzy. slightly lumpy on idle.smooth to drive and fast unless u floor it when as it gets to say 3500 revs is feels like it dont wanna go anywhere. i checked and checked the cam timing yesturday and its spot on. i went to a standard gasket cos i had a spare one and i had blown the gasket with the spacer in 300 miles. i used arp studs n nuts and it doesnt say in the instructions but u r supposed to heat the car up to one full cycle then retorque the nuts. the heat releases the stress in the bolts apperently and then they arnt at the right torque. andy at storm said he thinks thats why it went anyway. he says the same thing happened to him the first time he used arp bolts and he rang them up and thats what they told him. i was jus trying to do a quick fix cos i had an unused standard gasket. ive got to rebuild the bottom end soon and do the valve guides and valves (2mm oversize) n port the head.

anyways r u sure the timing is fixed? i would have thought u would change it for different compression? i used a 2mm spacer plate so would it not have to spark later to allow longer to fill the cylinders up? i dont know enough bout cars

[CorradoVR6-Turbo 0]

I use ARP with spacer plate etc and ive only torqued my bolts once on both my cars and have never blowen anything... :scratch:

 

As for the timing,its fixed as in you cant turn the dizy to change it but in the mapping side it will be changed in the ECU.

 

I would go back to your spacer plate if it was mapped with it mate.

 

other than that is there any fault codes?

[speedysmartypants 0]

i havnt used a vagcom yet to see. yeah i guess ive got to go back to the spacer plate. did u use one metal gasket and split it or use two? i used one and split it but i was thinking of using two one one the bottom of the spacer and one on top of it. may take the compression too low though? the other prob i had with the spacer is that the car kept stalling when stoping from high speed like pulling off the motorway from 80-90 coming to a stop and then it would stall. andy played with the trottle body but couldnt stop it happening. he said hes only had the problem with cars running lower compression and low boost. doesnt stall now im back to standard compression?

[CorradoVR6-Turbo 0]

What a load of tosh,stalling cos the CR is lower :lol:! stalling is down to the mapping mate...not the engine(depends),but supercharged and with your system ie idle valves are not the best.

 

Have you an idle valve or has it been removed? has your car been mapped with airflow meter or without?

 

I used one later 3 layer metal gasket,split it into three,chucked the flat centre section away and added the spacer plate.

 

Did you use two three layer metel gaskets either side of the spacer plate?

[CorradoVR6-Turbo 0]

like this..

 

[speedysmartypants 0]

i did the same as u with the spacer. it was mapped with the maf and idle vave. when he was fettling after i took it back he removed the black box thing off the idle valve. he thought it was down to the throttle body shutting too quick or something. i know he played with the damper. u reckon he couldnt be bothered to map it again?

[CorradoVR6-Turbo 0]

If you look in the FI thread,you will see how many peeps have problems with stalling,low running issues etc with superchargers,as the supercharger is consitantly drawing more air that the engine can cope with it need to be recirculated into the intake.

 

Same priciple when you are as you described,80mph coming to a jusnction and stalles,to much air flow via the airflow meter,overfuels and stalls....

 

Does your supercharger dump air to atmosphere or intake?

 

I had this problem,this is what i did as i got sick of stalling.i dumped the idle valve all together.Then i adjusted the idle with the throttle stop on the throttle body,never stalled. Downside is when cold, you need to give it some throttle untill a little heat as no idle valve to controll this.

 

Other than that...OBD2

[speedysmartypants 0]

dumps to intake. ive only just connected the recirc valve up cos when i had the spacer plate andy said the compression was too low to use it as the cylinders were taking everything given to them and the recirc valve would jus mess with the maff signals.

[CorradoVR6-Turbo 0]

Mate,there could be many reasons..i would go back to who you got the mapping done and get them to sort it out.

[speedysmartypants 0]

yep. cheers for your help mate

[Toad 0]

i went to a standard gasket cos i had a spare one and i had blown the gasket with the spacer in 300 miles. i used arp studs n nuts and it doesnt say in the instructions but u r supposed to heat the car up to one full cycle then retorque the nuts. the heat releases the stress in the bolts apperently and then they arnt at the right torque. andy at storm said he thinks thats why it went anyway. he says the same thing happened to him the first time he used arp bolts and he rang them up and thats what they told him.

 

Did you have the head skimmed when you removed it to fit the spacer plate?

[speedysmartypants 0]

no but it was refurbed by stealth in febuary and they said they made it like a brand new head so i assumed they did. when i did the gasket spacer i refurbed the head myself and stealth dont appear to have done a good job so maybe they didnt skim it. they didnt clean the valves or change the guides which needed doing badly. anyway ive got some oversize valves to go in and im gunna get it ported so i will get it skimmed then.

[Kevin Bacon 5]

I always check my ARP nuts 500 miles after installation and usually 1 or 2 need nipping up, but they're never loose enough to cause gasket failure.

 

Even standard VR6s can stall pulling off the motorway mate, let alone charged ones!. Mine used to do exactly that and I eventually traced it to a sticky idle valve. When cruising along at 80 constantly, the fuelling is lean, which causes high exhaust gas temps and guess what soaks all that heat up? Yep, the idle valve. When it's asked to open again after an extended period of being shut, it can sometimes jam shut momentarily because of all the heat soaking, causing the stall. You'll probably find it's OK after than first stall? Brand new valves are OK with that, but old, dirty ones tend to stick. There is a little screw in the idle valve (coverd by resin etc) which can be adjusted to stop it closing fully, which sometimes helps too......

 

Your stalling is almost certainly that or a dying / dead MAF mate.

 

When you say the engine is flat and gutless below 3500rpm, can you hear any pinking? The timing could be too high because you usually add on timing with spacers to compensate for the lack of compression, as much as 20% at some rpms and loads.

 

Regarding Stealth's heads, I've found they can be a little "wanting" at times too.

 

I like to replace all guides, all springs and all valves regardless, cause I'm ultra fussy, but Stealth tend to reuse any that are still in spec, which is fair enough and common practice with "standard" rebuilds. If you want a "Full" rebuild, you need to ask them as it costs more. New stainless valves from VW are quite expensive.

 

My schimmel head was brilliant for the money..... 12 brand new Ferera 1mm oversize inconel valves, 12 new guides, surface filled and skimmed, new HD double springs, titanium caps, cut back intake valves (stem diameter reduced), 3 angle seat / valve job ( more flow in / out of the port) and port matched (to Schimmel intake) inlet ports, uprated exhaust studs, etc etc....

 

That was ~ £650 plus shipping, which was very competetive at the time for that spec. 28,000 miles later, still running sweet and using far less oil than one of Stealth's heads.

[speedysmartypants 0]

I always check my ARP nuts 500 miles after installation and usually 1 or 2 need nipping up, but they're never loose enough to cause gasket failure.

 

Even standard VR6s can stall pulling off the motorway mate, let alone charged ones!. Mine used to do exactly that and I eventually traced it to a sticky idle valve. When cruising along at 80 constantly, the fuelling is lean, which causes high exhaust gas temps and guess what soaks all that heat up? Yep, the idle valve. When it's asked to open again after an extended period of being shut, it can sometimes jam shut momentarily because of all the heat soaking, causing the stall. You'll probably find it's OK after than first stall? Brand new valves are OK with that, but old, dirty ones tend to stick. There is a little screw in the idle valve (coverd by resin etc) which can be adjusted to stop it closing fully, which sometimes helps too......

 

Your stalling is almost certainly that or a dying / dead MAF mate.

 

When you say the engine is flat and gutless below 3500rpm, can you hear any pinking? The timing could be too high because you usually add on timing with spacers to compensate for the lack of compression, as much as 20% at some rpms and loads.

 

Regarding Stealth's heads, I've found they can be a little "wanting" at times too.

 

I like to replace all guides, all springs and all valves regardless, cause I'm ultra fussy, but Stealth tend to reuse any that are still in spec, which is fair enough and common practice with "standard" rebuilds. If you want a "Full" rebuild, you need to ask them as it costs more. New stainless valves from VW are quite expensive.

 

My schimmel head was brilliant for the money..... 12 brand new Ferera 1mm oversize inconel valves, 12 new guides, surface filled and skimmed, new HD double springs, titanium caps, cut back intake valves (stem diameter reduced), 3 angle seat / valve job ( more flow in / out of the port) and port matched (to Schimmel intake) inlet ports, uprated exhaust studs, etc etc....

 

That was ~ £650 plus shipping, which was very competetive at the time for that spec. 28,000 miles later, still running sweet and using far less oil than one of Stealth's heads.

 

sorry for my ignorance but i dont know what pinking is so please tell me. i bought some new 2mm oversize valves off a guy from the vr6 owners forum for £110 which i thought was a bargin. i will try and get the guy whos gunna do my head to copy what you've had done to your head. apart from ports matched to schimmel intake cos i dont have one. any recomendation on an adsact specification? theres suposed to be something special about his valve guides but i cant remember what cos i have a head like a siv. thanks for your help

[Kevin Bacon 5]

Pinking / pinging / detonation / knock is caused by fuel exploding, rather than burning in a controlled manner.

 

Petrol engines are considerably quieter and smoother than diesel engines (except early 90s Fiesta engines!) for that very reason, the fuel burns. Diesel fuel explodes, hence all the clattering noises they make....and that's what pinking sounds like in a petrol engine....a diesel type clattering when you put your foot down hard at low to medium revs.

 

Pinking is BAD. It's usually always caused by too lean a mixture or excessive timing, and in rare cases, too much fuel. Your ECU should control pinking (knock sensors) before it becomes audible, but sometimes slow and tired knock sensors don't react quickly enough.

 

That's a good price on the +2mm valves. That really is the limit on the 12V head though, any more and they start touching eachother!

Yeah leave the inlet ports as they are then for now.

Valve guides are normally just bronze for it's good anti-wear properties. I'm not aware of anything special in that area, but if your man can fit something better, all the better for you!

 

If you use the Schimmel cams or similar with those bigger valves, and providing the exhaust gases can escape quickly, you'll see some nice power and torque gains across the whole range.

 

Are you going turbo? I've got a memory like a sieve aswell....

[speedysmartypants 0]

ive not noticed any knocking yet. i would love to go turbo in the future but for now i want to push for a modest 350bhp with my rotrex. its gunna take me soo long though cos it costs soo damm much. near future plans are the head done properly, 83mm wossner low comp pistons, uprated fuel pump and uprated injectors. ive got to strip my gearbox (never done one before) to change the diff bearings from my missus hitting a hay bale on a duel carrage way at 60mph. it totaly screwed the cars handling and im slowly replacing everything to try and recover it. the diff actually knocks if you wheel spin and over bumps. bit worried it may pop out if i dont do it soon. hopefully by the end of the year i will have sorted everything then i can get some sort of cooling and crank up that boost!