silverboy

Any suggestions?

911Jetta

You RS owners are never satisfied...and have the $$ to really take these cars to the next level! I love that.

I've learned so much about these engines and what's possible from reading (and rereading) threads from both Colin (9Meister) and Geoffrey (Racetek Engineering). These guys are doing incredible things with our engines...and they also do a wonderful job sharing their findings and explaining it in simple straightforward way. When I win the Lotto....

964RS to get the first 9m 4.0 litre race engine....
https://rennlist.com/forums/showthre...ferrerid=19642

9m 4.0 litre 964/993 engine in development
https://rennlist.com/forums/showthre...ferrerid=19642

9m 4.0 litre high lift - 450hp & 400lbft at flywheel - in stock 964RS!
https://rennlist.com/forums/showthre...ferrerid=19642

9M USA Dyno Chart
https://rennlist.com/forums/showthre...ferrerid=19642

There are many, many more threads! Great reading.

silverboy

911Jetta - thanks a lot for the links. Very informative. I love this engine. I am looking at a 3.9l kit, DRC cams, ARP head and bottom end bolts. I now have a FVD LB2 and straight pipe exhaust. Also just bought steel wide body fenders and rear flares with Fikses so it should look pretty hot!

NineMeister

My advice is not to build a mongrel engine and expect it to make good power. The overall performance of every engine built is not defined by the sum of the components, it is defined by how well the components selected complement each other and this can only be determined by extensive testing and development.

I've built many engines that make great power and have built many more that don't, inevitably we find that the ones that underperform are due to one or more components that are either not manufactured properly or where small design changes have had a dramatically negative effect on expectations. A recent example that comes to mind was a 9m built 3.82 litre race engine that ran had run at 425hp for nearly 4000 track miles which I subsequently rebuilt with a GT3 crank, new 9m rods & a complete high lift valve train. First pulls on the dyno it made only 370-380hp, however roll forward 3 month on the dyno & after several cam timing & valve clearance changes it posted over 450hp (even though I am still not happy with the cam profiles we ended up with). We then found huge improvements in acceleration on the road by writing individual cylinder 3D fuel trim tables for the Motec M800 ecu & the car now clearly outperforms the customers own 997GT3RS.

So, to go back to your original question: a properly component-matched 3.75 litre on Motec will outperform and outlive a mongrel 3.9/4.0 litre, so don't be duped by the old adage that bigger is always better.

Indycam

Or maybe reverse engineering a known good motor ?

On a completely separate and unrelated subject ,
how much to rent one of your 4l motor for the weekend ?

JHC5478

I own a 91 C2 Targa. I have recently been pondering whether to upgrade to a newer more powerful ride or tweak my 3.6L. The car has 80k miles, HKS -2" springs, and 17" cup wheels.

The threads posted by 911jetta are great, but i didnt notice anyone upgrading, nor did i see any references to, Targas. Im wondering if this is simply due to lower build numbers and less popularity as a track chasis, or if there is a deeper reason...

Colin, do you see a lot of customers upgrading power levels in their Targas? Can my chasis handle 350-375hp for street/light track purposes without significant additional structural upgrades? Is there a way to get more information on US builders that have worked with the Ninemeister upgrade packages?

Thanks-

Black930

I have heard that they will twist a bit. No experience with it. Just what I have been told because of the power.

silverboy

Indycam - the 3.6L is a decent engine but plagued by design flaws in the exhaust and its barn door type MAF.

Colin - I would like to set up a '9M' pedigree type of motor but don't want to spend too much given this my second P car. My expectations are not high. If I'm able to hit between 300 to 335 BHP I would be happy with the following mods - 4.0L, DC 24 cam, FVD LB@ + tune, full exhaust. I think there is low hanging fruit for this power range. Above that then the marginal utility of money spent gets painful.

JHC - nothing wrong I guess with doing that but like Black said you can't expect much in the handling dep't given the chasis flex.

Rocket Rob

Geoffrey who is active on the RL 964 forum works with Ninemeister. I would start with him. http://www.racetek-engineering.com/

elbeee964

O.T.
Dear Lord... just when you think the 'barn door' MAF vs. film sensor kerfuffle rested in peace, up it rises, again, all zombie-like.

(cuing Loren in... 3... 2... 1...)

evoderby

"Have fun" ;-)

evoderby

If 300-335Bhp is your goal and you're on some sort of a budget then why do you insist on increasing displacement?? I'm not saying that a 4L engine with cams and MAF will not perform, it just seems a bit overkill with the potential of mismatching components just like Colin warned you about.

If you want 4L then by all means go ahead, make sure you get the best kit possible as some oversize piston designs a quite poor in terms of power. If on the other hand you're willing to make best use of what you have got a MOTEC or equivalent kit with MAP sensor and large injectors will already bring you 325Bhp. Dropping the engine for cams and sports springs/retainers adds to the budget and gets you well across the upper level 335Bhp mentioned by you.....

Do you have an RS flywheel already? The money saved on pistons/barrels easily allows factoring this in......really makes your horses dance!;-)

Rgds,

Harald

silverboy

Motec is a good idea too I guess but not cheap too. I got the car used and it rides like it has an LWFW. Builds revs quickly and sometimes dies in traffic when revs drop sharply.

I was also planning on having my head ported by someone I know who has over 35 years experience.

I just think increasing displacement is a easier way of getting HP. I can always add the other stuff like a Motec in the future.

sml

I'd prefer to have the reliability & performance of Motec first ... and then add the other stuff like increasing displacement in the future.

clutch-monkey

i've actually seen a track car coupe that was originally a targa - apparently the logic behind it was that the extra bracing that came with the targa car added to the stiffness when converted to a coupe, giving it an edge over a normal coupe