MaxBoost

I sold my Jun III's that were in my last setup, and I plan on buying something more aggressive from EF-1. But I need advice on which grind to choose, since I'm using more stroke and jun valvetrain

Here's my setup
B18 Block
GE Sleeved
85mm Ross Pistons
Crower EconoLite Rods
GSR Head
Jun Valvesprings
Jun Ti Retainers
Jun Cam Gears
Skunk2 IM
Erik's Racing 70mm TB
HeaderTech SS Header w/ 3" Merge
Stock Exhaust with 3" QTEC
Hondata to tune it all

Compression will be 12.3:1

What cams?

They must work with my GSR LMA's or if ITR's are any different, then I guess I could upgrade if I had too. Also they must be compatible with my valvesprings and retainers. Also I guess I can't go with too much duration b/c I don't think my block will be safe to rev past 10,200 daily w/ those thin sleeves. Choices are below.

M20--> 274 duration 11.5mm lift. Available in Regrind
M21 --> 274 duration 11.6mm lift. Forced Induction (FI), NA for Smaller motors
M22 --> 284 duration 12.1mm lift. Strong NA, Wild FI
M23 --> 292 duration 12.1mm lift. Spicy NA
M24 --> 298 duration 12.1mm lift. "JUN Killer" NA Drag
M24E --> 303 duration 12.7mm lift
M25 -->310 duration 12.1mm lift High RPM NA Drag
M25E -->316 duration 13.25mm lift

Thank's for the help.

b19coupe

Stay away from any cams with much more lift than 12mm with GSR LMA's and Jun springs. If you want to upgrade your LMA's to ITR and get a better valvespring for high lift, you should be good for any cam except the M25E-that one is going to require more care to install.

MaxBoost

So I would assume that my choices are the M24 and the M25, I can't really run the E's b/c they have so much lift. I wonder what if I would be able to make more power from the M25's with the extra duration, or if that duration would just make my powerband to peaky, and need me to rev it too high.

dfoxengr

id run the M24

MaxBoost

If I go with Toda or Portflow valvesprings and ITR LMA's can I run the M24E's safely??

Looking at the specs of the M25E's I think, it's safe to say that they are race only cams. Those things are huge.

MaxBoost

Bump! Come on guys, I need help cus if I want my motor finsihed sometime this century I need to order my cams already.

dfoxengr

ask ef1

MaxBoost

BTW: Nice motor setup B19coupe. It's good to see someone who takes the time and spends the money to do everything possible to make a motor run right. Nice selection.

indomotor

Do you know how much your head flow?In order to get the right cams for your combination,you need to refer to the cfm chart so you won't over cam your set up!

slofu

first things first: for what price Rocket offers the ef-1 springs and Ti retainers, and the reported problems/failures with Jun's stuff, i'd worry about running even Jun 3s for long with that valvetrain, let alone wilder cams, and i'd certainly invest in the ef-1 stuff (in fact, i already have).

next, are you using the 87.2mm b18c crank, or the 89mm b18a/b, b20b/z crank? i don't think you'll have a problem with either on the GE sleeves at <11K rpm if everything is measured, balanced, matched, and assembled properly (ask SgT, Larry at Endyn, Erick's Racing, of IB Jeff), but the 1.58:1 r/s ratio with the 87.2mm crank and stock-sized rods will be a bit easier on the sleeves than the 89mm crank, unless you get longer rods and appropriate pistons (wrist pins moved up). Endyn and Import Builders offer these. you can use the larger crank and gain the 40cc from the longer stroke, and still retain the same 1.58:1 r/s vs the 1.54:1 stock B18b/b20b r/s ratio. this will also slow the piston speed a bit, and allow the engine to breath more easily, extending the power band. (see graphs on http://www.importreview.com to see the difference.) using shorter rods and the same stroke can yield better low-end power (sacrifices some high rpm power), but is generally harder on things, especially bearings, rings, etc.).

also, the head and manifolding should be configured together to account for the bore, stroke, rod length, desired rpm band, and application before you choose the cams.

it seems as though the m24s should work well for you, but there's only one way to find out...

MaxBoost

I was going to invest in either the EF1 or Toda Valvesprings and have my Jun Ti Retainers TiNitrided to increase hardness. Until then I was going to use some milder cams.

As far as the stroke. I'm using an 89mm Ls crank, with crower "long "rods, and ross 85mm pistons w/ the wrist pin moved up a bit to help out the r/s ratio.

My head will be stock for a while, later I will be adding a custom head ported for 51mm ITB's..

MaxBoost

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hybridvteceg &raquo;</TD></TR><TR><TD CLASS="quote">ask ef1 </TD></TR></TABLE>

Cus he's impossible to get a hold of.
Rocket & Camp1320 are both impossible to reach.

dfoxengr

foreal. that sux..lol..harass them

slofu

if you get the ef-1 springs, which i'd recommend over the Todas (for $ and quality), get the ef-1 Ti retainers. i think that Rocket said that he guarantees them against defect/failure when used with his springs. (i don't think that he'll replace your engine if one breaks and causes total failure, but the fact that he's making a guarantee on a race part says that it was likely made for street use, unlike Jun's, etc. products made 'for race use only', which virtually exempts them from all/anyresponsibility in the case of any problem.) also, i think i remember him saying that he heard from a reliable source that Toda B-VTEC springs were just Honda H22A outers with stiffened inners- at a premium price. ef-1 springs are so damn stiff, that i'd venture to say that if you mis-shifted and hit ~12K rpm, the valvetrain might be ok, even if you tossed a rod or melted a piston.

70mm TB seems too large for use with your 2L and S2 IM. from what i've read, large plenums (like Skunk2 IM) "like" smaller TBs; 64mm should suffice.

good choice on the header and tuning. Jun cam gears are also good.

ITBs are cool, but loud, and gas mileage sucks ***. low-end hp/tq isn't the best, either. i'm really curious to see how Larry's (ENDYN's) new carbon fiber intake manifold performs. it's supposed to make power up to 11K rpm, with the proper configuration(s), without killing low/mid pwr. i don't doubt that it does well (as it should for ~$1200), but again, i like to see results. (his 2L engine is close to yours- 89mm stroke, 1.58:1 r/s ratio, b18c head, hytech header, 13.44:1 c/r, 84.5mm bore.) i think he said that he pulled 185 ft/lbs at the wheels from 6K-9400RPM- i don't know if that's with the new intake or not, and again, i don't doubt it (check out CHEETAH's graphs), but with all of the drama/doubt/hate on the boards, i'd not be surprised if he never posted a graph. (look at the h-t drama over Jerry's IB engine- FS; see classifieds.)

a few details which should help you: the core-shift in the skunk2 IM castings is usually bad; the runners typically underhang the intake ports in the head significantly, creating a step which the intake charge has to "climb" up into the intake ports of the head; this causes lots of turbulence (bad), and a likely loss of power/efficiency. get some Devcon Liquid Aluminum (not JB Weld, etc.); it's not cheap, but it works well. use some Prussian Blue Compound to measure the amount of mis-match at the intake ports, rough up and clean the runners of the S2 IM free of oil, etc. with acetone (don't get fingerprint oil on them, either), and fill in the dimensional difference with the Liquid Al, about 1" up into the manifold runners. this should be done preferrably after the head has been ported, though a slight 'step' backwards can help prevent reversion without harming positive flow (as long as the step is not too big). apply the stuff with a clean tongue-depresser or similar instrument, and make a 'dam' with some masking tape on the IM flange, to help keep the liquid in place. you can also drill some small pits/holes in the intake to help the liquid stick, or even drive small srews up through the bottom of the runners, around which to form the liquid, so as to help better secure it. it is thermally stable to 250F, but you don't want it to shake loose and fall into the engine (ouch).

sanding the sharp edges of the pistons (domes, valve reliefs) might help prevent detonation, and having the combustion chambers in the head opened to 85mm to match the cyl bores will help, and make things flow better.