Pinto dyno run

[rallyrob]

If only...

It's the biggest mistake anyone could ever make... But I have heard similar stories.

Lets just call it stupidity, along with carelessness.

[Erikmex]

These things happen. Everything is fixable

[Dyno]

Good point re. double enrichment, I guess that situ can cause a nasty rich dip in power when coming on cam that would appear off cam related

Double enrichment is what you got when you miss a corner, end up with to little rev's, engine make sad sound and if you still try hold on the power in worse case start to shake like mad end finally stall.

On the dyno, I'm talking about a water brake in not controlling the RPM this point is very clear visual. The wider you open the throttle the worse it's running and finally stall when you fully open. If this dyno is in closed loop RPM you will miss this point compete because the dyno start to reduce the power when the engine fail to make the RPM's. Same for the rolling road. I was not aware of this issue, what it caused and how to correct it before I learned to use my dyno in the correct way. I do know what it cause, know how to minimise but your can never get rid of. As long as you got the right cam, carbs and tune the problem will be out of the power band you normally use. If you start with the wrong cam or any other wrong setup it can end up as a full disaster

And yes, it can make a huge dip in the torque graph

[mariors2000]

Hi Erikmex I seen a early post back a couple of years that you had 196 hp with an srd mainfold and ht1e camshaft or did you have ht1 cam in before I'm confused or have I read wrong cheers Mario.

[Graham]

As and aside when i talked to SRD about buying a manifold of them they didnt claim any top end power gain but said it would give more midrange.

we have just run andy pipes 2.3 pinto up on T+R's rollers, with the SRD manifold ( it did have an ashley 3 piece), as ever they started very late in the day, and in my book the job was never finished, they wouldnt allow my to swing the cam timing, or even wind more than 22 degrees max advance into it! so what we could of ended up with is guess work, and as i also changed the head spec its not a proper back to back comparison either but results were interesting, torque was up 7lbft, we had the same peak power but at 1000rpm lower so we currently have 208bhp at only 6500rpm!

[Dan Johnston]

K&N’s can rob a lot of power, I usually use ITG filters, I have one for this car, generally when there’s a lot of stand off carbs work better with a filter. They seem to prefer having a small chamber to dampen the pulses when using a cam with a lot of overlap, I’ve seen cars perfectly set up with the inner wing covered in black fuel....but there’s virtually no stand off with this engine so I don’t run filters often, it’s only used for sprints and trackdays

My pinto with GP1 Head & cam & 48's drop dead once i popped on filter socks on my long 120mm trumpets ...

[katana]

I believe anything located close to the open end of a trumpet / ram pipe will hurt performance - open or free flowing foam. An ideal solution IMO is the ram pipe in a plenum / chamber that allows the intake to draw from front, sides and even behind and of relatively 'still' air. The old 'tea strainer' type that clip over the ram pipe flow loads of air but muller hp big time! I think a minimum of 1" / 25mm clearance over the ram pipe is good although more is better - foam, even open cell types just disturb air flow, leading to turbulence - not good over carb jets.

[Erikmex]

That was first engine test before I ran the engine in properly

[Erikmex]

I guess it depends on the head Graham. I’m using a Vulcan Ultimax head, the gains were on the top end. When I first swapped it ran lean with a 160main, it was fine with that main on the grp2, swapped to a 170main and it gave much more top end and held on to power longer, that was in combination with a 2deg cam timing change

[Graham]

I guess it depends on the head Graham. I’m using a Vulcan Ultimax head, the gains were on the top end. When I first swapped it ran lean with a 160main, it was fine with that main on the grp2, swapped to a 170main and it gave much more top end and held on to power longer, that was in combination with a 2deg cam timing change

the engine needed a shit load more fuel in the midrange

i wanted to swing the cam timing, but didn't get the chance, which is what happened the last time that engine was on the rollers, i did get to have a quick play with inlet trumpet length, interestingly by shortening them i could get it to hold onto power longer after peak, all be it at the expense of a bit before and at peak itself, so as a mod in isolation shorter trumpets were not of benefit, but if a timing swing can lift peak torque up the rev range a bit then in conjunction with the shorter trumpets it could be win win