Went out testing the car last night after doing some suspension mods brought the car on boost in second and bang!!!

 

eh? How does that happen?

 

Blimey!! If you're gonna break something though, may as well make a pukka job of it!!! Lol!

 

hi
is that a jenvey one

mark

 

My brother did that on his Alfa 155.

It was caused by a dropped inlet valve that allowed a big slug of fuel air mix back into the intake just before it was ignited by the spark.. boom...

 

Rang jenvey this morong they said because it was a backfire ie explosion it would not be coverd under warranty and it would be Ł650 to repair plus vat

It did this to the bonnet

 

Not good mate but I'm sure a man of your means will have it up & running in no time

 

bet you shit your pants

 

Yes mate

 

It also dropped this onto number 3 piston I dnt no how but it didn't damage anything on the way in !!

 

What you going to do Dean?

 

Was it on a base map?

 

As I said on the phone, it's a fucker but you're so lucky the engine is still mint.

 

holy fuck!.. but i suppose it is cast alloy and quite thin.. i best get some money to gary quickly for a inlet as i can see the queue growing...

 

I've ordered all the parts for the engine and will have it built back up first thing after checking it all over as for the inlet I dnt no as of yet as Gary is on holiday and mapping is one week away!

 

not good dean,hope you can sort a inlet asap

 

Jesus! Like someone else on here said, if something's gotta give, might as well go in style, hope it doesn't happen to you again mind.

 

alloy HO inlet again then, no????
shitter pal, thin walled alloy inlets do have their weaknesses if backfiring i guess.
gary on holiday is a bigger too, going to have to wait i'd guess, really can't see the money for replacing the jenvey to be fair.

 

funny how everyone ranted and raved about how good these where, deano is sooo lucky it didn't take the whole engine out, for 1300+ I would of expected a bit more structural integrity than that, oh well crazycage to the rescue it is,,,,again. But dean don't forget to ask gary for the flow figures and bench tests :-(

Chin up young jedi

 

It's clearly had some force go through it, Dean said Jenvey told him these inlets are tested to 3 bar and fail at 6 bar! And yes, I have a Jenvey lol

 

when gary gets back will see if he is up for trying to replicate a miss fire, how the hell you do that I don't know, only way I can think of is seal a plenum up and tap a spark plug hole, fill it with some fuel the power the plug, I havnt a clue but it would be interesting to see.

I know gary has redesigned his inlets further now, removing the trumpets for one and has now adopted a much smother bezel style shape which is cnc machined into the plenum face from one billet. He is working closely with a very experienced engine builder and hopefully will be doing some flow tests on his and other inlets just to see what the results are. This is something I have yet to see another (including jenvey) doo but its a requirement everyone seems to want.

Out of interest what sort of boost equivalent would be generated by a misfire? Surely mk1 focus rs inlets and likes would be prone to breaking in this sort of situation? mind you they probably don't misfire lol

 

Any inlet would fail from an inlet backfire!!

 

its the first time ive ever heard of such thing which was why I was a bit surprised. Is there a way to test for this sort of scenario sizt?

 

Depends on cam timing, general engine spec and what the map is like on there already. It's most common when hitting the limiter/launch control w/ignition cut when using nitrous (hence the danger to manifold thing in the original fast and furious ) but it's not un heard of for a FI engine to pop it's inlet

 

Glad all is well with the engine mate.

 

Just to add as well, you were lucky with the engine. Also I imagine that Gary could use part of the Jenvy inlet when making you a new one

 

I've seen it happen a few times on various engines over the years. Unfortunately, engines run in semi sequential / batch fire configuration are more prone to it as the fuel injectors fire in pairs but only one cylinder will have the inlet valves open. This means that the other cylinder will be left with fuel sat on the back of the inlet valves for a brief period until they open.

We can reschedule the mapping Dean, that's no problem. I'll give you a bell later on to discuss.

 

If the shit really hits the fan let us know, I'm sure you could borrow a inlet on a you bend it, you mend it terms.

 

 

Maybe worth looking into a burst panel mate. Quite common on expensive intakes, normally used with the nitrous lot as they love blowing the inlets to bits.

 

Thanks very much for the offer mate I may have one sorted fingers cross

Engine is getting built back up first thing in the morning! As for the jenvey Daz c is going to try and work his magic with it !

So fingers crossed everything sounds sweet when it starts back up

And thanks for the comments boys

 

did think that after the offer lol.

 

Major shitter

 

Very poor casting for the money but it would take a lot to withstand an inlet back fire, how that ended up in the cylinder without touching is madness

 

F##kin hell thats mad.Glad the rest of the engine is ok.

 

I cant believe you guys when you say "very poor casting". This is an event the manifold was never intended to encounter, and his map was way off. Its his own fault for pushing the car on boost on a half finished map, not the inlet manifold. Casting or not, this would have f***** every intake manifold out there.

 

Cheers for that

 

F**k me you did a proper job on that!! Sure you'll be back on the road in no time!!

 

not entirely true is it though, when i was first setting up my old megasquirt on the zetec turbo i had loads of backfires through the inlet at first and didn't blow it up, it was a thick cast item though.
it seems that being only tested to 3BAR and exploding at 6BAR is a bit disappointing though.
lot of money for what you get IMO, one of the reasons i didn't venture into one, but it hasn't gone over night, it has done many hard launches up the pod already i believe.

 

Cable tie the fucker together it be alright