I originally posted this in JRSC thread just wanted more input.

Hey so I accidentally bought a m45 instead of a m62 blower.

http://hondamarketplace.com/showthread.php?t=2967999

So I just bought a m45 blower with lht after cooler with heat exchanger really cheap. I got all excited since I got the deal so cheap I forgot that LS and b20 JRSC are m45s.


So what should I do?

Will the m45 still make pretty good power on my motor. Its a sleeved 83mm motor set up for turbo 9:1 comp and b16 head with supertech valvetrain.

Should I just run the m45?

Is there anyway I could keep the JRSC manifold and lht cooler and just mount a m62 blower?

Should I just sell it?

Thanks lemme know whats possible.

 

Some things posted from the JRSC thread


Quote:
Originally Posted by Veris
Effectively no one has hands on experience with a m45 on a B-series vtec. Only a handful of JRSC were made for the Del Sol vtec in the mid 90s before they switched to the m62.

320whp is IMO the maxium output on a m62.

The most people have made with the m45 [that I am aware of] is 210whp. I suspect the upper limit is around 230whp in a perfect setup.

I base it on this estimation.
320whp x (45/62) = 232whp

I can't comment on what options you have with that version of the lht cooler. I'd contact John at LHT.
Yah 232 is a little low for me =(. Especially for a fully built motor lol can make like 220 all motor if i up the compression.

Ricer no 7 by me

I make 187 whp on 9:1 compression now. Will it fit if I just redrill the holes on the flange or do I need the m62 to fit properly. Should I just slap it on see what it makes?

 

Quote:
Originally Posted by Natural Aspirations
The LS manifold is the same as the B16/GSR with different holes drilled. It is possible to widen the opening and attach the M62 and keep the LHT intercooler

Ricer no 7 by me

Has anyone done this. I think I can pick up a m62 blower pretty cheap and use the JRSC LHT manifold.

 

how much did you pay for it? that LHT manifold is worth its weight in gold because they charge 1100 dollars for just the manifold to be retrofitted. id love to get my hands on one of those but i dont have the finances for it.

 

the thread is there about how much a paid. I Paid $1600 that is why I jumped on it.

Might sell it

 

i see the ad, if you paid 1500 for it, its worth a shot at keeping it, run a much larger heat exchanger behind your front bumper, something intercooler sized to keep those temps WAY down, not that dinky little fluid cooler that came with it. the only issue your gona have with that blower is you may need to run a larger pulley rather then the 3.0 that is attached to it, the kit was designed with a pulley that max's the blowers RPM @ 7000rpm, not the rpm's your probably revving to with your vtec setup, which will push it over the limit that eaton recommends.

 

1600 after injectors.

Yah I rev at least to 8000 rpm. Any suggestions which pulley to use. An is it worth it will I actually make some power I was originally shooting for something like 280 with the m62. But with the m45 will 240 whp be possible? If not I probably going to sell it.

 

emailed lht with some questions

anyone have any input

 

The issue is air flow, the m45 just wont flow enough cfm to make the higher power numbers your looking for. If you can modify the manifold to put a m62 on it, I would go that way, if not I would see if you can't sell this one and go to the aftercooled m62. No sense in doing it twice if your wanting the 280ish out of your setup you will need the m62.

 

I'm kind of leaning towards selling it. The thing is my car is at a shop right now getting rebuilt. So hoping I could just slap this once it done being rebuilt. With 240 whp I might be craving more power though.

 

Go here to my website and use my GSR calculator.

http://www.ftlracing.com/media/CALCS/

Update the engine displacement to yours.
Update the m62 blower to a m45.

Then play with the pullie configurations to see what is possible.

Keep the blower speed below 18000 rpm. Blower pullies under 3.4" are unheard of but may be possible. Typical recommendation is 3.8" or larger to prevent slippage. Some people have made as low as 3.4" work for street applications.

I got you'd need a stepper pulley, and crv pulley, and a 3.2" pulley to generate 230whp. Blowerspeed would be 18200rpm. You'll have pulley slippage issues with a pulley that small, but it is doable.

People suggesting snake oil, ie 275whp on a M45 don't know what they are talking about. It'll require the above crank and alternator pulleys plus a 2.5" blower pulley and blower speeds of over 25,000 rpm. This on a blower designed for 14,000 rpm.

Good luck with your decision and project.

 

if you dont mind me asking, im looking at your LS calculation sheet, how did you come up with flow efficiency calculations?

 

It was based on head flow numbers using a vtec head as a baseline. Then fine tuned based on real world results. If memory serves .85 or .88 was the 'theortical' estimate. They gave results slightly low so they were fudged higher.

 

Thanks I'll try to play with the calculator. Kinda confusing

 

It seems to read incredibly low, i put in my numbers and it comes out to around 194whp even with the specs i gave it for my new setup, when my calculator that I used with actual flow bench numbers input, seems to read about 70hp higher.

 

My calculator has accurately worked for dozens of setups. In 5+ years you are the first to complain about its results. In a perfect setup it might be a few whp low. On a very poorly tuned setup it could be a high. There is NO way it is 70whp low.

I suspect your calculator (what ever it is) is bhp vs whp and ignores blower losses, but I have no idea. You've provided too little information for me.

 

And what are you using to calculate your numbers?

 

Im using desktop dyno to calculate crank horsepower. Your calculator seems to net me about 190whp.





granted thats the sim with the smaller set of cams, my other sim reads about 20hp higher.

 

Two differences stand out.

1. Your calculator is showing 10psi vs 6.6psi in mine.
2. Your calculator is bhp (flywheel) vs mine (whp).

My response is simple. Your calculator is calculating boost incorrectly. Your blower overdrive (1.9 vs 1.85) and displacement (1973 vs 1979) is basically the same as mine. My m62 generates 10psi. A blower 1/3 smaller won't generate the same boost.

In regards to flywheel my calculator does show it in the cell above whp. ie 190whp or 236 bhp (crank).

It is of note that if you generate 10psi in my calculator you will get 213whp (278 crank). That matches your calculator's output. I used the crv crank and a endyn/mvm stepper with your 2.8" blower pulley to achieve this.

 

so your estimate on how much boost the blower will make is based on taking a 1/3rd of the psi away from what you get on your setup with a M62? if im understanding that properly? Also, how am i supposed to correctly calculate blower belt drive ratio, i was under the assumption it was the crank pulley size divided by the snout pulley size, in this instance 5.875/2.8 = 2.1, correct?

 

No the estimate is based on flow and displacement. The m45 is 1/3 smaller. Delivers ~1/3 less air flow.

2.1 is correct as the blower overdrive. I mis-typed at 1.9. My calculator showed it correct.

 

so using these corrections i get



with a 20% drive train loss, yours shows 173whp, blower efficiency of 60%

so i input that on dd and i get this



so..since this is only crank hp i do the calculation for a 20% drive train loss, and i get 217whp...right?

 

Drive train loss is 12-15% in a FWD honda.

Your calculator does not appear to be removing blower losses. In this case ~ 20whp.

 

So did you sell it or keep it? imo you should sell it! you dont wana make similar power to what a properlly built n.a motor would be 220+whp. In the end your deff gonna wana take it off and want more power, the motor dont even need low comp. pistons let alone sleaves! and second your motor is built for a turbo why not just slap a properly sized turbo kit and tune that and make gobs more hp than what the jrsc would. get a good turbo that will spool quick and support the hp you want, or Look into a rotrex or vortex or pro charger centrifigal superchargers. you can tune that motor with any of these style super chargers and easily hit 400+hp! with a great liniar power band! youl never get that kind of mid and top end with a jrsc. If i had sleaves i would be boosting 15psi on my ITR motor and hit 400- 450hp! theres a civic tuned at churches that made 450hp @16psi on the same procharger unit so the potential for big peak power is there. Dont get me wrong i pumped out 285hp out of my last JRSC setup and that freakin motor was killer! i swear it was fun! I remember walking all over a moded evo on a uphill tug match! his turbo was way out of its range! i dominated his turbo cause of its lag! but i find the pro charger unit im using to be more effecient,The jrsc is fun for a lil track car but its just it makes you thirst for more power especially when your passed by a another car with a simple n.a setup like a K swap.
https://honda-tech.com/forums/showth...2556604&page=9

 

The car was originally built for a GT35r set up. I was running it NA saving up for my turbo kit. It was going to be a drag car. Then kinda got tired of drag so my new build was going to be for road racing auto x and fun street power. So I was going to go with a gt28rs or a m62 with lht intercooler.

The motor is being rebuilt right now since its leaking oil and has a blown head gasket. There cracking it open seeing whats wrong with it. So if the pistons are toast I'm upping the compression to 10:1.

I'll probably either go m62 lht or a gt28rs

I donno about the rotrex or vortex expensive and pretty much same as a turbo.

Just came in the on the 30th so still deciding what to do with it.