Engine Dowling......what is it, when is it required? I notice most of the high hp cars in Aus have their engines Dowled. When is this required? Is it more needed on a drag car than a road race car? At what hp level is it recommended?

 

500hp+


-Ted

 

what exactly is it?

 

it's used with high boost high output rotaries. basically it uses more dowels as reinforcement of the housings to keep them from being pushed/flexed out from the rotors and also from cracking the side housings.

 

There also seems to be an increasing thought that maybe a very rigid type of plate 'ontop' on the sump would be better for reducing flex.

I've also seen this method done a few times..

but as others have said, really not worthwhile until your running crazy ammounts of boost in a high Hp application.

Edited because it was incoherent, possibly because of the bottle of red wine consumed before posting.

 

Thanks guys, so it won't be necessary for my plans on a measly 400 hp

 

From what ive heard the 87-88 Blocks have a tendancy to twist once there in the 350 HP range and up. The rear plate always seam to crack this happened to a friends Turbo II pushing 375 RWHP the car ran high 11's. This is why having the motor pinned is recommended, but I still have to say its all about tuning. BDC told me he doesent believe in pinning his motors. But I say everyone has a different opinion on this subject.

 

Bingo.

I've seen motors not even breaking 300hp to the wheels crack dowel pins due to detonation.

I believe RICE RACING is making 550 to the wheels with an undoweled motor.

Keep the engine out detonation, and the doweling becomes almost unnecessary.


-Ted

 

Absolutely!

Friend of mine is making 550 to the wheels on his daily driven street ported series 4 block with no doweling.

Granted thats on 116 octane and 23 psi but still moderate timing.

And i've made around 400 rwhp for 2 years on my stock j-spec no problems.

Jason

 

Great info guys, it's nice to hear it's in the tuning, I plan on getting my motor professionally tuned so hopefully I won't have any problems.

 

Is dowling used in high HP N/A's power that a very large bridge or P-port would make?

 

Not that I know of...

It's mostly for high boosted turbo motors.


-Ted

 

i was told by a good builder/tuner around here that running higher boost around 15psi on a decent single turbo would twist the block a bet and you should get your engine dowled. at least two or three..

 

nah i've run over 20 psi on mine, no problems. and 15 for a 3 years, between 3 different turbos.

get it tuned correctly

 

Well like RETed said, as well as Rx_treme, and my self previously stated and agreed upon. Its all about tuning. Then again everyone is entitled to there own opinion. I would say if your not boosting very high like White FC stated then it wouldnt be necessary. But im thinking of doing it as a preventive step more like a precaution, due to the fact that I have someone here locally offering to pin my block, and brush the plates for $275.00 which is not exspensive at all considering they do very good work, and its all done with the proper equipment.

 

And who might that be?


-Ted

 

Marko of ForceFed (a local builder tuner, not very well known outside the lower manildand of British columbia, Canada.) is the most likely builder.

He's said before that dowelling is necessary above 300 hp... but I completely disagree.