Speedworks

So last season a local Belgian race team purchased the white/yellow/black Pettit race FD.

However last season they didn't manage to get the car running correct and today (race season opens tomorrow) they blew the engine again (3 times last year)

Every time the apex seals blew.

Dispite several attempts to get a tech spec on the Pettit race engine, I haven't found anything usefull yet (if you do please post or mail me)

Basically it's a single turbo (don't know which one) witha Halltech E6k (I presume) engine management.

I'm not a part of the team but regularly in contact with one of them and trying to think along what could be going wrong.

Last year they had the FMIC setup as Pettit build it, but overheated every time. I suggested them to go V mount which turned out to be the solution for heat problems.
Last Thursday they did a 2 hour testing session which went verry good, no probs.
Todays time training turned out a disaster as the engine failed again.

engine spec (as far as i know)
13b REW
single turbo
Vmount
Halltech E6K
Greddy type S and Tial BOV's(could be Greddy Race BOV as well)
LARGE race radiator

Main issue according to my own limited experience is that the fuel/air mixture is wrong and is causing detonation, which (as we all know) is fatal for the rotary.

Moreover they went to 3.5mm Apex seals (they told me,no idea who sells those) and they are still breaking them. Some serious detonation should be there as the engine was newly rebuild and confirmed 100% OK.
Basically they acould be running it pretty lean which could be a factor. The team always raced Miata's and they might be tuning it like a piston engine, which is all wrong. Secondly, they are in the endurance class so the could have it running towards the lean side for fuel economics... no good

Another issue is that their ignition timing might be off track as I inquired for the porting on the enigne. This being a pretty important factor in respect to setting ignition timing. They answered it was a normal port (as in NO porting at all)
A single turbo, 13b Rew wth NO porting making +- 450HP ??...uhmmm don't think so. Unless screwing up the boost is the only thing you do.

I also know they are running 4 equal injectors. Which could work although after reading several single turbo setups they always run richer injectors in the secondaries (850/1600cc fe)

I know this isn't much info, but it's the only one I have at this point and I will be mailing to my contact for extra info's.

I would just like you guys to give me some of your brainstorming ..

Many thanks

Neal

Carl Byck

For starters, nobody can help, until we see the ignition maps at a minimum, optimally, we need port type, injector sizes, fuel delivery specifics(devices/line sizes for critique), plugs used, fuel map, Ignition type, AFRs, oil, and water temps, turbo, on and on. I would get this info, and post it on the Engine management forum. Why won't Petit provide the info? Carl

JEC-31

My thoughts exactly. I've heard of problems like these (not knowing what's inside) when ppl run vintage cars built by long-gone shops - but Pettit?


One thing that caught my eyes was "3rd blown engine". Who's rebuilding them, or if replacing what are they replacing them with - Mazda remans?

PureSephiroth

well there's the problem...
They have a Haltech. They should use it. They need to get to a dyno with a wideband and tune their A/F ratios. If its detonating that's why they're cracking seals...

Speedworks

Well that's my opinion.

Carl, I'm going to send your questions to them and hope they will be able to give some good info.
I'm also going to stop by the shop this week as it's notso far from my work. Maybe get some print out/screen copies from the Halltech to work further.

Thanks in advance!

PS. I will send an inquiry to Pettit as well. They should be able to give some decent info

RETed

I don't understand why it's blowing up?
Are you using bad gas?

If the race car was running well before being sent to you guys, why would it start eating engines all of a sudden?
Did they switch the map out???

If you can get a hold of the map, I'll be glad to give it a quick scan to make sure everything is kosher...


-Ted

RacerJason

iTrader: (5)

That very car ran in my series; the SCCA SPEED World Challenge during the 2001 season. The team that campaigned it is local to me and I can forward you their contact info if you wish as I know they didn't have as many problems as it sounds you're having.

Cheers, Jason

PureSephiroth

if the engine was running well before and now started going through engines then perhaps they are using a lower octane fuel than the car is tuned for. That could be causing detonation and cracked apex seals as well.

Godzilla-T78

I have a whole list of tech specs from that car and have quite alot of knowledge about it having spent so much time at pettit during my stay doing media and pr. email me if you have any questions. Also last i checked it was running a Link system not haltech.

Speedworks

Any technical info would be highly appreciated from my side.

You can always send it to speedworks@pandora.be

The fuel/octane issue could be something to work on. i have no idea if it's OOk to use octane boosters or race fuel at all in the series Pettit ran the car.

By accident I was reading the regulations for the series over here and it said tha the teams should use pump gas at ALL times.

Pump gas meanshere 98 octane leadfree super fuel. I know the euro 98 oct and US fuels are not quite thesame, so I see this could be a driection to look out for.
Godzilla, could you send me those specs?

Many thanks

Neal