Down on power... A LOT

[Peter]

Got my car back from the dyno this weekend but the result was to cry for...
I expected at least 200+... the person that tested it said something is very wrong..

I ll tell you first about the specs: 2276, MS230 heads, JPM cam (282° @ 0.050), IDA's with 40 vents, 1 5/8 header, pointless 009 with flamethrower coil, should be around 11/1 CR (now I am doubting)

The engine is tuned now and drives well, no strange sounds, it just lacks a lot of power: it produced only 165 hp

I wonder if my cam is already going flat, so I will first check that, the cam timing could be wrong too (I just installed it at 0)

Some ideas? I know the header and vents are small but still..

Thanks!

[Peter]

Something I forgot:
the tuner said the engine didn't want fuel:
he could only get it to run well with 135 main jets ... anything more and it would sputter and go way rich...
Very strange to me!?

[BeetleBug]

Hi Peter,

Flywheel HP or Wheel HP? And have you checked that the engine basics are OK? Done a leak down test? Checked lift? Does it actually fire on all 4 @ all rpms?

If the engine basics are OK then there clearly must be some parts in the mix that are not "compatible" Until today the least HP I have heard of using those exact heads was a 2332 with a FK89 cam, approx same CR as you and it produced 207 Flywheel HP. The reason - his exhaust. He later changed to a CSP exhaust and it produced 238 Flywheel HP after the swap.

Best rgs
BB

[alex d]

fuel pressure?

[Peter]

checking the lift is the first what I will try..
a leak down test is not the same like a compression test? not sure

It actually sounds pretty good 

[Peter]

BB, can you specify a bit on engine basics?
a compression check and lift check will tell me everything, no? or valve opening time is also needed?

I wasn't there when the test happened, but I drove it after the tuning and feels and sounds normal

[BeetleBug]

BB, can you specify a bit on engine basics?
a compression check and lift check will tell me everything, no? or valve opening time is also needed?

I wasn't there when the test happened, but I drove it after the tuning and feels and sounds normal

Engine basics:

- Runs on all 4 at all rpms
- That the cylinders are round
- Have correct lift
- Correct basic timing
- non leaking valves

A compression test will just tell you if one or more cylinders differentiate from the others. A leak down is basically the only test you need to perform and it will tell you if you have a leak and where the leak is (piston rings or valves)  

A engine with such efficient heads as yours need:

- Compression
- Air
- Ignition
- Fuel
- High RPM
- And a good exhaust

From what I can read above I instantly react on the 40mm vents and your small exhaust.

-BB-

[Peter]

Thanks a lot!
I know where to start now

[leec]

Header seems small for those heads?
Also, it's one rolling roads result, could it be they are inaccurate rather than your engine being the problem?
Lee

[Peter]

header is small, I know, but still I expected more power.
and about the dyno, I highly doubt something is wrong with that

[LGK]

Hello Peter,

Was this 165hp with fanbelt? Engine dyno or rolling road?

You have 48 intake valve,what's the sense of fitting MS 230 heads if you "choke" it off with to small exhaust and vents?

Dem's engine made 214Hp with smaller camshaft then yours ,still 48IDA's,and it was a 1 3/4" header.Compression less the 11/1 ...and 044 heads.

A healthy 2276 with MS 230 heads,and stock 48IDA's with no raptor-stuff,still makes close to 240-245Hp,even at 10.5/1 compression depending the camshaft.

You're not talking about the torque,what numbers you got?

Something is way off ,check everything as per beetlebug suggestions...i'm sure you will find the culprit.

Good luck to you.

Steve@flat4to6.com

[Peter]

Hello,
Here's the dynosheet...
it was on a rolling road and belt on.
Honestly I built the bottom end to get 220 - 230 hp,
but re-used some parts from the past that could be updated later (like venturies and exhaust)
and drive like that for a while until funds allow for a better exhaust etc..
It seems to work ok until 5500 and then the torque decreases rapidly.
I guess thats the evidence that I am choking it, right?

[Peter]

Just took off a valve cover to check the valves for lift..
I turned the engine over and measured the difference in valve height with a caliper.
For all 4 valves I have a lift of 15 mm and the camlift is 11.07.
Looks correct with my 1.4 rockers..
Next buy the tool to make the leakdown check...

[Erlend / bug66]

Weird curve..

You could probably give it less fuel down below, and more on top if I read the curve correctly.

Is there some weird ignition going on in the dip?

[Jim Ratto]

do you have some kind of filters on the air horns? the 135 main jet comment leads me to ask that

I'd wonder about ignition break up as well. Or wrong emulsion tube.

[Fiatdude]

Usually there's a cross over of the torque and HP at about 5300 -- So what I'm looking at is the HP line staying flat or falling from 5800 on up to 7000 -- which could be valve float, too tight of valves, spark/ignition woes or restrictive exhaust/intake. -- -- It's like the engine reaches 5800 and says "that's it, I'm done"

[Zach Gomulka]

Usually there's a cross over of the torque and HP at about 5300

Horsepower and torque ALWAYS cross at 5252rpm, since HP is a function of TQ. I believe since this was measured in Newton meters it does not?? Not sure, anyway it's difficult for me to analyze a graph that doesn't do that.

Peter, considering you're measuring wheel HP, with the belt on, I don't think you're down a whole lot. There is an easy 20% more at the flywheel.

[alex d]

11:1 compression ratio will need some spark, you might want to try with something more powerful that what you have in there ignition wise

[Felix/DFL]

That lambda curve looks really bad.
Lambda x100 same scale as hp...

Its way too rich down low and way too lean up top. Lambda 1,2-1,37 max? That will cook it and no suprise that the curve drops.
Maybe not enought fuel suply? The 135 main is even not suited for that combo...the transition to main is even bad (massive drop 3500rpm), what's your jetting?

Didn't the operator tell you something about the bad lambda? Maybe consider changing that too.
At full throttle lambda 0,85-0,87 is your aim.

Checking to main vitals is ok, but it looks thaz fuel/jetting is your problem...

[Torben Alstrup]

Usually there's a cross over of the torque and HP at about 5300

Horsepower and torque ALWAYS cross at 5252rpm, since HP is a function of TQ. I believe since this was measured in Newton meters it does not?? Not sure, anyway it's difficult for me to analyze a graph that doesn't do that.

Peter, considering you're measuring wheel HP, with the belt on, I don't think you're down a whole lot. There is an easy 20% more at the flywheel.

Wake up guys. That´s only correct when you measurew in lbs. with Nm it does not do that.

Apart from that, sumtin´s wrong. But I can´t tell you what. Maybe cam timing.
The exhaust is definitely too small for those heads and cam.

T

[neil68]

I have a similar engine 2332 cc with MS230, 10:1 CR, IDA's with Raptor 44 mm vents & stacks, Raptor cam with 10.8 mm lift and 15.2 mm with Scat 1.4's and Wasp Stage 2 header with Magnaflow muffler.  This combo made 204 HP to the wheels on a Dynojet roller.

I would recommend at least 42 mm venturies, F2, 180 mains, 3 mm needle valves and a larger header.  The Wasp alone is said to be worth 13.5 HP on a 2276 cc engine, in back-to-back testing.

[LGK]

To Zach,

I believe Peter's dynosheet shows corrected FlywheelHorsepower,even if it's on an rollingroad dyno,it can measure and calculate flywheelpower and loss at the wheels/gearbox,at least that's how my rollingdyno works...

Peter can  confirm maybe?

Rgds Steve.

[PPRMicke]

Just took off a valve cover to check the valves for lift..
I turned the engine over and measured the difference in valve height with a caliper.
For all 4 valves I have a lift of 15 mm and the camlift is 11.07.
Looks correct with my 1.4 rockers..
Next buy the tool to make the leakdown check...

Hi
Would think that it is an ignition problem that you have for the lambda curve
or it overflows needle valve (maximum pressure 0.20 bar )
/// Micke

[volkskris]

To Zach,

I believe Peter's dynosheet shows corrected FlywheelHorsepower,even if it's on an rollingroad dyno,it can measure and calculate flywheelpower and loss at the wheels/gearbox,at least that's how my rollingdyno works...

Peter can  confirm maybe?

Rgds Steve.

Not Peter, but it was corrected to flywheel HP.

[Zach Gomulka]

To Zach,

I believe Peter's dynosheet shows corrected FlywheelHorsepower,even if it's on an rollingroad dyno,it can measure and calculate flywheelpower and loss at the wheels/gearbox,at least that's how my rollingdyno works...

Peter can  confirm maybe?

Rgds Steve.

Not Peter, but it was corrected to flywheel HP.

That makes more sense. Thanks for clarifying.

[Peter]

Lambda suddenly got really rich, he could only get it down by using the 135 jet I believe.
No filters, Jim.... And the tubes are the F4's....
I still have some Wasted spark coils somewhere... they are begging to be used.

[Jim Ratto]

Lambda suddenly got really rich, he could only get it down by using the 135 jet I believe.
No filters, Jim.... And the tubes are the F4's....
I still have some Wasted spark coils somewhere... they are begging to be used.

F4 should be working opposite of what's going on.
It should come on, on the richer end, as the load comes on at mid-low rpm, and without correct air corrector, go lean up top.
Something is off. What air corrector jet is in it? Are the 135 mains you're using true 135 (never been drilled)
The other thing would be header size, choking engine off and causing a ton of reversion.
A substandard ignition won't like any of the above.