3.4 Dyno Chart

[Jeff Alton]

Originally Posted by icarp

Small port size meaning 34 mm from the stock 80-83 3.0 engine ?
Or 39.5 from 78-79/ or the 42.5 from the 3.2?
thanks Jeff , great job

Small port 80-83. Blended in the guide area and ITB manifold blended/matched. This is the first small port/decent displacement motor we have built. Very happy with the results.

On the larger port motors, although very pleased with the power/tq, I would love to be able to play around with injector placement/throttle plate height etc...

I have seen too many different dyno plots of similar motors with a GT3 or 964 intake manifold on top of the ITBs with varying degrees of curves. I am not sure if we could get more torque out of this 3.4 with one of these manifolds. However, I would love the chance to play around with different manifold/cam/exhaust combos to see what is really there.

Everything we do we like to verify before we offer an opinion...

Cheers

[KNIGHTRACE]

Here is a 3.2 I built over 14:1 compression big cam big valve for a comparison.

[KNIGHTRACE]

not the best cam for this application but it is a good running motor the AFR gauge is only hooked up on one side.

[KNIGHTRACE]

[KNIGHTRACE]

Their doing good work in BC, I couldn't get the pump gas dyno sheet to upload but I was just trying to share as results are similar. Nice work.

[Jeff Alton]

Looking good there Knightrace! A little lower AFR and some more power sitting there?

Tell us some more details about this motor!

Cheers

[KNIGHTRACE]

Yes, the dyno was break in and reference, fine tune after in car. dont know end result but seemed a little faster.

[mikedsilva]

Seems like an amazing amount of performance from a 3.2... wow

[KNIGHTRACE]

Pretty good but not a chance it will run on pump fuel. Full race motor almost 6" rods. Thanks though, William

[stownsen914]

Very nice results Jeff and Knightrace!

Knightrace - I realize it may be part of the secret sauce, but any chance you’d be willing to share the cam grind used in that motor?

[Jeff Alton]

Knightrace knows what he is doing, there is no doubt of that. I can understand not sharing all the small details! Great work on his end.

[slow car]

Just ran my 3.4 ,46 PM),GE60, twin plug,1,5/8" headers( open) 10.5:1 JE

Be interesting to see what the new mods will produce ....50mm PMOs, GE80s 12.5;1 JE total seal rings 1.75 headers.
102 octane. will do .
Motor striped now.

[K24madness]

Originally Posted by Jeff Alton

And the latest 3.2SS that just got tuned.

When judging results of a motor build I look at the shape of the power curve to determine if I achieved the desired results. To me this is an ideal curve for a street driven 911. The power (torque) comes on strong 4K+ and stays there through redline. That flat curve in the proper working range is what I look for. Below 4K it’s not slouch either. Plenty of torque before it comes on the cam. Well done Jeff!

I see you’re working with John for Cams. I enjoyed my conversations/collaborations with him. By focusing on the before dyno curve we achieved exactly what I was looking for out of my build.

[Jeff Alton]

^^^ Thank you.

yes, john has been great to work with over the years. Torque is what makes these motors fun on the street and fun on track. Sure, we could get more peak power, but the power band gets a fair bit more narrow.

cheers

[KNIGHTRACE]

OK, I will share what the specs are on the motor, it is an average race build not off the charts. Heads were 3.2 heads with larger valves radian cut both. My 1 3/4" headers compression about 14.2:1 and the cams were 171/141 webcam Gt3 oil pump and rods were Carillo custom length around 6" but I cant remember. 70.4 stroke, 98mm cylinders. On numbers it is easier to get the small motors to make big HP per liter because of the short stroke it takes longer to stabilize vacuum in the intake runner and the effect of that is your peak torque number is higher in the rpm range. (TQ)(*RPM) divided by 5250 so HP numbers are a cumulative result of rpm. I am in the process of producing some heads that have already made over 130 hp per liter. They will be made on extreme castings. My piece of advice to guys building there own street motors is this. ALWAYS go with more stroke in your air cooled motor if it is a street or autocross car.. Please do not fall for the short stroke myth.. I know myth is a hard word but it only is important in race application where your above 5500 rpm all the time and have to run a certain liter for your class. This is my best advice I can give to anyone building a motor. William Knight

[sp_cs]

I should have followed your advice more keenly, William. Although, thanks to your design input and cam choice, I have an excellent engine, it could have been more; I had to fit a GT3 pump anyway, so should have fitted the 80.4mm crank. With the cost of all the work I had undertaken, it would have been relatively cheap at the time.

[jpnovak]

Great numbers for all these builds.


Now on to this snippet...

Originally Posted by KNIGHTRACE

I am in the process of producing some heads that have already made over 130 hp per liter. They will be made on extreme castings.

This deserves its own thread...

I am listening.

[KNIGHTRACE]

If anyone wishes to contact me for crankshafts. I stock up to 82.4 mm and factory motorsport 80.4 mm. KNIGHTRACE@MAC.COM
I also modify your crankshafts into a kit of mine and rods and pistons and 78.4 mm is very affordable if you start with a 3.2 crankshaft. my number is 615.969.4917 William Knight
example on a 3.2 I can have your cylinders made to 98 mm and there durable and the crankshaft to 78.4 mm and you have a 3.55 liter motor and it is a brilliant change and quite affordable.

[Jeff Alton]

I am with Jamie...

And yes, we will be in tough knightrace to talk some more! Thanks for adding to this thread!!

Cheers

[KNIGHTRACE]

Heads are going to be on the Super Veloce motor first I am pretty sure, I will let Taormina Racing release information on the new motor. William