Guy Croft Lincoln UK 01522 705222

Hello, Concerning the books, I have both. The first one is full of highlights of many colours. It helped me a lot to prepare the head and the engine. Thank GCT (former GCRE). I take the occasion you give me to give a feedback to Guy concerning the second one. In fact it is difficult (for me) to read...

I hope it just doesn't get too complicated here (hint - Robert!!) that I have to start looking-things up B4 I post!! G More complicated is more interesting ! I would like to get a summary concerning the proportion of the effect of the waves and the other ones on the filling of the cylinder. Even a ...

Thank you Tom (merci beaucoup même!)

mv² ! of course. So v is more important.

Guy,

You can move the thread but say where it will be ;o)

Thank you for this forum. The learning way.

Robert

Wow ! 1 % of contribution... I did not know that it was so low... Is it true ?! What do you mean by "momentum of the moving air/fuel column" ? Is it the gas velocity ? Cross sectional area is crucial, since I reduced from 45 to 40 mm the intake runner (trumpet) the power increased a lot. T...

OK Timinator. Let's speak about pressure waves instead of resonance. So the waves can be tuned according to the length of the runner and the camshaft timing in order to increase the incoming pressure (or the reverse in fact). In the equation I use there is a coefficient k giving the rank of the harm...

OK Guy. So I have to take precaution using this maths and avoid plan on the comet (direct French expression translation meaning to avoid dreaming).
I will come back to you for specific questions implying commercial matter so may be directly by e Mail.

Best regards,

Robert

Thank you Guy for your post. Sorry I don't understand your phrase "I don't want to rain on your parade Rob but this is GC Q&A" (you know I'm French and I don't master English totally, I would say partially) The calculations I made are based on tract length and camshaft timing. The rela...

The photo is from Internet I have no snapshot from mine. The dimensions are in the previous attached picture. When you say "higher resonance adds a lower amount of wave pressure" do you mean higher harmonic or higher revs ? I agree concerning the higher harmonic. I learn if it is revs. Tha...

I am convinced on resonance existence (the dyno curves show them). If I modify the length of the intake tract I can get a resonance with a lower harmonic (H2) at about 6900rpm. Since the signal is higher for the lower harmonic (fundamental is not targetable) I wonder how it can improve the torque so...

Hi Timinator, I use it up to the shift light set up at 6250rpm. The ECU cut ignition at 6500. The pistons are cast (105TC OE) not forged. I precise it is FI and static ignition. Do you think it can be used more than 6500? I just want to analyse this case in order to improve it. My header (exhaust) i...

From my very very small experience I want to share here for analysis my “results”. This is the curve of my engine (130TC, original cams, preparation of the head following the best I could do the GC recommendations, valve grinding by GC, guide from GC, CR 10.7:1) I calculated the resonances of the in...

Hi Guy, It is a pleasure to read you. I see a BIG hump at 3500 ! I try an answer: To fill the cylinder we need 2 phenomenon’s, the flow and the acoustic (superimpose onto the first). Blower certainly brings more flow without need for acoustic ? In fact my concern was how to increase filling with the...

Hello,

I cannot imagine there is no answer about this question...
Waiting for the specialists, will be patient. :)

Robert

Hello, On my Montecarlo I used new pipes and so used the same routing as original. But if I have to redo that I will use braided hoses directly from M/C to spliter (T), proportioning valve and calipers avoiding as much as possible brass unions. Concerning fuel I would try to keep the gasoline the co...

Hello Guy, This is a question about matching well the resonances of an engine system (intake and exhaust). From your experience, is it better to shift the intake and exhaust resonances in order to spread the humps on the rev band or is it better to have the same revs ? So is it better to have more h...