jim wat kind of headers are u gogin to chose the dc one on ur car or a better header
aint the kamiakze header the best one out
Forget the word "psi"... it simply doesn't matter as a reference. There are sooooo many variables that affect pressure that making comparisons between two engines is almost impossible. A fair comparison is blower speed... and ultimately, CFM. There is a point in any blower where the lobes are moving so fast that they can no longer ingest air on the intake side to pump through the blower and ultimately into the engine. This point effectively destroys volumetric efficiency and generates super-heated intake air. This "point" is a blower speed... lets use 15000 rpm as an example. This means that if I wanted to keep my maximum blower speed at 14900 rpm, and I have an engine redline of 8500 rpm, I would try and create an overdrive ratio of 1.75... which would actually create a blower redline of 14875 rpm. Whatever the "psi" is at this blower speed, with my displacement, my exhaust, my intake, etc. is... what it is. Incidentally, I hope that it is only 11 psi so that I do not have to change MAP sensors... the GM 3-BAR is really ugly !!!
At lower boost levels, both the LHT intercooler and water injection will create lower intake charge temperatures, and thus allow one to increase boost slightly without incurring detonation. Unfortunately, since high-boost applications are already reaching the performance limits of the blower itself, there is no headroom for gain. Blowers have efficiency ranges just like turbochargers do... when you keep them within those confines, you will make the most power possible.
Consider BoostedEX's example again: His bone stock JDM B16A (1595cc and 10.2:1 compression) @ 10 psi made 207 wheel HP. I installed a CRV shortblock with Crower rods and JE pistons (1973cc and 10.5:1 compression), and using the exact same pulleys as before, made 252 wheel HP @ 7.5 psi !!! So, by increasing displacement and increasing compression, we made large gains without changing the blower speed.
How is this you say...
Simple. The additional displacement offers greater breathing power within the engine... it will use more air per revolution than a B16A will. Since the blower moves a fixed amount of air based on rpm, it would make sense that less pressure would build within the intake manifold. Also, the blower is most efficient at lower blower speeds because the amount of time that the blower lobes are open to ingest air at the inlet is LONGER... which translates into greater fill per revolution. As the blower speed goes up, the fill rate goes down. When the blower lobes reach redline, the fill rate is dismally low and the air within the intake manifold begins to recirculate... which makes REALLY HOT AIR !!! Obviously, there are additional scientific forces which also affect the airflow (intake pressure pushing back toward the blower to limit incoming air is just one), but I am simply offering an example or two to illustrate the TRUTH about what we can and cannot accomplish with the Gen 3 M62 blower.
jim wat kind of headers are u gogin to chose the dc one on ur car or a better header
aint the kamiakze header the best one out
I am using the DC Sports JDM 4-1 with the 2.5" collector.
<font size="2" face="Verdana, Helvetica, sans-serif">Yes!!! Very good idea. Please make a new thread, I'll be the first to sign up for one of those babies!Originally posted by JRCivic:
mgro,
I am considering the creation of a high-boost stepper pulley for race applications only... maybe we should create a new thread to test interest in this piece !!!
We will have to figure out how to properly predict boost levels first though, your results with BoostedEX still baffle me...<font size="2" face="Verdana, Helvetica, sans-serif">Napkin check: the blower displaces 1litre/rev and redlines at 14k, thats 14000litres/minute. One cubic foot is about 28.4litres. At 90% VE the flow is about 444CFM, pretty close!
CFM... that is an interesting discrepancy. Oscar gave me the figures, and I assumed them to be true... unless I have somehow misquoted them. Maybe knowing the formula to find potential HP from a given CFM would bring this into focus better. I may have gotten the CFM number incorrect, however, I am fairly certain that the flywheel HP value is accurate.
Corky Bell's books show crank-HP to be about CFM/1.5, a quick Google confirms this. 460CFM thus gives us 306 crank HP. I guess you can spin the blower a little faster, and our Honda engines are probably more efficient then the typical engine so 300 Wheel-HP should probably be possible- just!
<font size="2" face="Verdana, Helvetica, sans-serif">Hmmm, I agree- if its only 1.5 degrees that cannot be it. The larger bore will probably negate part of that anyway. If its not timing then it must be CFM, but the last figure in my post above shows the difference in CFM to be tiny at these pressure differences (10->7.5psi)?!?
As for your theory about timing between the 1.6L and 2.0L engines... there is only an additional .5 degrees of timing in the big motor at peak over the JRSC HIGH BOOST maps... and no more than 1.5 degrees more throughout the powerband !!! Now, I would not say that this alone would create nearly
60 wheel HP, nor did intake temperature seem to make any difference.
What about cam timing and de-shrouding of the valves in the bigger bore engine, could those be a factor increasing the Ve???
best regards,
Mark.
ps: don't forget to start that thread on the stepped-up stepper pulley! [img]tongue.gif[/img]
mgro,
I am using an Unorthodox Racing Ultra Rc crank pulley (my design) and my stepper pulley with the stock blower pulley (4.0"). I am considering the creation of a high-boost stepper pulley for race applications only... maybe we should create a new thread to test interest in this piece !!!
heheheh
CFM... that is an interesting discrepancy. Oscar gave me the figures, and I assumed them to be true... unless I have somehow misquoted them. Maybe knowing the formula to find potential HP from a given CFM would bring this into focus better. I may have gotten the CFM number incorrect, however, I am fairly certain that the flywheel HP value is accurate.
As for your theory about timing between the 1.6L and 2.0L engines... there is only an additional .5 degrees of timing in the big motor at peak over the JRSC HIGH BOOST maps... and no more than 1.5 degrees more throughout the powerband !!! Now, I would not say that this alone would create nearly
60 wheel HP, nor did intake temperature seem to make any difference.
well, I haven't posted here in probably 4 years, but it is nice to see that this engine is almost ready to go. Good luck hitting your power and e/t goals [img]graemlins/thumbs_up.gif[/img]
how about adding a wet kit in there nos 80 shot go for low 11
I am prepared for a dry shot... 50 to 75 HP. I put RC 550's in this engine for that very purpose !!!
Excellent thread, I can't wait to see the engine fully built and running. I am about to rebuild my GSR motor and reading this makes me want to increase displacement to 2 liters. [img]graemlins/thumbs_up.gif[/img]
I was wondering, I saw a pic of your fuel line and I want one for my GSR in my Civic, where can I order one of those fuel lines?
I haven't posted in this forum in a while, I guess I have been missing out....
Congrats on your 4000th post.
Let's play "Fear Factor".
Your task is to place a 200 hp Honda power plant into a 1978 Alfa Romeo Spider.
P.S., I'm gonna keep the GSR [img]biggrin.gif[/img]
Posting Permissions
Bookmarks