why is my engine not powerful?

[Matti johansson]

Do you run on tps (alpha n) or vacuum (map)
If you run Tps that ignition table wont give you any nm.
Too small numbers around 3000rpm.

Did the tuner use any knocksensing device?

With that camshaft and singelthrottleblade. I would go by TPS not map, it would be too erratic.
And choose a good tps, not the bosch Volvo 850, that is also too erratic. Bmw have one with internal return spring that gives solid readings.

What afr or lambda did he aim for, and did he reach it?

Tell him that you want afr or lambda readout on dyno sheet.

.
/Matti

[bmw2101]

its on map sensor, and it is a bmw one! he was aiming for 14 afr i think, i did get a print out but i never kept it. Im not sure how he does knock sensing but he is a really good tuner, quite well known over here.

i think that cam is a low quality one, is that the problem?

[Matti johansson]

no, its not lowquality.
just a lowpricecam that probably dont do youre engine right.

you see when looking at youre ign table i dont know what ign it gets when on map since it migt be a restriction in the intake and then it moves to more vacuum at rpm.

but i think youre engine will take about 30degrees(probably more when 11:1) from 3000, and it does not get near that what i can see. so i think you have more to get out of it.
volvos are not so sensitive and what i see the inj table is more "modern" than what this engine wants. think more litke a distributor!!

how long time did the first dynosession take?

[bmw2101]

it is strange but he said he defo wanted to use the map sensor as itll run smoother. I was also told by someone over here who also runs a rolling road, that the plenum style setup i have [the kjett with injectors welded into it and a 63mm inlet] and a 300deg cam do not go together. That is why i was really interested about the H cam.

Chris had the car for maybe 1.5 hours on the rollers, but it was a running car when he got it, he has mapped it maybe 8 times before with different set ups.

It at one point had a t4 cam in it, and it had a lot less power, it had the lh 2.4 style inlet then, and it pulled strong all the way threw, worked really well. thats the power i need, not top end..

[Matti johansson]

Well, maybe the cam will do the job, but i dont think the ignition is fully tested. Maybe uptop. But if you get the midrange up maybe you e got a killer!!

I would have aimed for 13,2 afr. And tested more ignition.
On dyno if youre unsure. Do 26deg stiff from 3000 and up, do 2-3 runs. Then test +2deg and see the different. Then do +2 again and youll se when it doesnt gain as much, then youre getting close.

And if youre curious, connect to megatune and show rpm, map and ignition (if you have afr show that to).
Put it in high gear and film steady with telephone.
Then we will se what ignition it gets, if the intake is restricting, and if it gets fuel.

[bmw2101]

right ok, im going to take the car out on saturday. I can do a log and ill play it back threw megalog viewer, and you can see how the ignition is when i drive. Looking at the table, and roughly guessing i think it is about 25 degs mid range, but i am only guessing.

I do have a lambda but it isnt reading correctly, it must need calibrating or something, it is miles off.

[quattro]

Matti, would you say this power/torque curve is typical for a Volvo B23 original VOC rally engine?
https://www.dwautokonsult.se/voc-crossk ... mappning-1

As far as I can tell it's showing power at the wheels.
If that's the case, then max power is about the same - and at the same rpm - as the engine in this thread
But the torque curve is looking much better. Hardly any dips at all, just a fairly small one at 3300 revs.

It points in the direction of the cam. It has too much duration for the engine set-up.
And I think you are right about the ignition as well.

[Matti johansson]

His whp is in my dyno engine hp. so a voc at 154-160 ehp is fairly normal.

There is a chanse that the cam can work even with much duration, and that is because of restricted intake, it wont make maxhp, bur it will be a long curve wich sometimes kan be easier to drive than a stron engine with short curve