Modifications to production based engines

[Roninho]

Hello,
every now and then i see some articles stating that multiple cars (GT cars and Daytona Prototypes for example) have modified production based engines.

What i am wondering is, how much do these race engines still resemble the Original engines? Are these just small changes or do they involve big changes? And what type of changes?

thnx

[Damian Baldi]

Originally Posted by Roninho

Hello,
every now and then i see some articles stating that multiple cars (GT cars and Daytona Prototypes for example) have modified production based engines.

What i am wondering is, how much do these race engines still resemble the Original engines? Are these just small changes or do they involve big changes? And what type of changes?

thnx

They generally keeps the block and crankshaft, but the rest is usually new. Fuel, water and oil pumps change to electric, or mechanical but lighter and more robust versions. The biggest work for development are the engine's cylinder heads, cams, valves. Most of the work is there to get more power.

Some constructors usually just develop the cylinder heads. Some examples of this are F1 Matra v12 engine from 1967/68 (using a Ferrari block), and Yamaha F1 engine from early nighties (using a Judd v10 block). They saved time using an existing block.

A reverse example is the v8 used at the TC2000 here in Argentina. It uses a british v8 engine, made from two Kawasaki Hayabusa cylinder heads. This way they saved all the work to develop the heads, just working a new block.

I have to say that I like the use of stock engines blocks, as current P2 and DP classes do.

[andrewc]

In the case of Formula Three until the new bespoke racing engines came in last season, the engines had to be production based, and the rule was that you could remove metal but not add metal.

Thus the production blocks were lightened and polished, often bored out or skimmed to desired capacity. Heads were polished and ported and skimmed with bigger valves (if possible), different seats / valve guides.

Cams, valves, cranks, rods, pistons and flywheels were generally special special items for this application.

The cars were dry sumped and the sump and cam cover were generally used as structural mountings to bolt engine to the tub.

Front cover, bell housing, inlet, exhaust and ignition systems were often completely unrelated to the road car as well.

[carbon_titanium]

Originally Posted by Roninho

Hello,
every now and then i see some articles stating that multiple cars (GT cars and Daytona Prototypes for example) have modified production based engines.

What i am wondering is, how much do these race engines still resemble the Original engines? Are these just small changes or do they involve big changes? And what type of changes?

thnx

About GT cars, GTE cars keep the block and crankshaft of the street engine, while all other parts are replaced with more updated parts. The main aim is not to achieve insane power outputs as old GT1 cars (that unrestricted had >700hp) but to gain enough torque to set the lowest possible revlimiter!
examples: street 458 italia revlimit is at 9000rpm (570hp)
458 italia GTE revlimit is at 6500rpm (about 500hp)

[Roninho]

Thank you guys for the replies.

As for the updates that are done on these engines, are those newly developed parts or are those parts that have to be available to the public as well? So really developed by the engine guru, or use items that are available?

[Roninho]

And additionally: Is the work that is being done on the engines ''Hi tech''? Or is this relatively ''simple''?(as in you just need equipment, budget and obviously some talent for this)

Since i have a bit of trouble of explaining what i'm actually trying to ask a bit of explanation to this question
The story of an OEM sayin ''we race our production engines'' is obviously a nice marketing story, but what i wonder is how much technology is being put in the updated/racing versions of these production engines. Are they really still the production engines or are they true racing engines having not much in common with its mother the production engine?

[Damian Baldi]

Another good example is the Porsche Cayenne engine that won Daytona in 2010. It was sent to Lozano Brothers, and finally it was a Porsche engine with lot of parts used to tune up Chevrolet engines.

[carbon_titanium]

agree, more or less like the engine used by the audi in DTM that comes from an honda unit if am I not wrong

[Damian Baldi]

I would like the idea to give a block and crankshaft to the teams to let them develop the heads with a partner, instead to give them a generic engine like the P2 in 2017. That way engine tuners will keep a place to work.

[carbon_titanium]

Originally Posted by Roninho

And additionally: Is the work that is being done on the engines ''Hi tech''? Or is this relatively ''simple''?(as in you just need equipment, budget and obviously some talent for this)

Since i have a bit of trouble of explaining what i'm actually trying to ask a bit of explanation to this question
The story of an OEM sayin ''we race our production engines'' is obviously a nice marketing story, but what i wonder is how much technology is being put in the updated/racing versions of these production engines. Are they really still the production engines or are they true racing engines having not much in common with its mother the production engine?

usually each manufacturer has his own tuner specialist; that could be inside the same company or not.
The 5.5 V8 of corvette DP has been tuned by richard childress racing; most of ford racing engines are tuned by roush and yates; sprint cup chevrolet engines are tuned by hendrick motorsport! and if memory helps me, the engines used in first models of 550 GT1 have been tuned by BMW USA

[deggis]

Somewhat related: http://www.racecar-engineering.com/a...ves-the-breed/