wotsup, yer i was just wantign to no, if i get a new cam, powerband ruffly like 5000-7000rpm.. wot do i have to do to let the engine safely rev to 7000-7500 or above, and wot can the stock valve train ect handle,
thanx
fraza
wotsup, yer i was just wantign to no, if i get a new cam, powerband ruffly like 5000-7000rpm.. wot do i have to do to let the engine safely rev to 7000-7500 or above, and wot can the stock valve train ect handle,
thanx
fraza
dont worry mate, that'll buff right out
are you efi? if you are, the rev limiter will limit you to 6500 on the a20a3. but your best bet for help would be rjudgey. just wait til he finds this thread and you'll have more info than your wallet can handle.
on the a20 it does not have alot of power....and snoopy the rev limiter is like 6850RPM lol i red lined 2nd today...and hit the damn rev limiter....i was doing close to 75-80...i love my cam gear...it pulled strong....
anyways the best bet is to rebuild the whole engine with racing parts...
1989 Honda Accord LX-i
B18c1 swap since 7/2011
175whp and 132tq
Redzone tuned
rebuild the whole engine, lol im not made of money, i just wanted to upgrade the cam like not ALOT but a bit, so the engine can still handel it on stock internals
dont worry mate, that'll buff right out
Originally Posted by fraza
yeah but dont hope to be reving to 7-8 k....this is not a V-Tack engine...
1989 Honda Accord LX-i
B18c1 swap since 7/2011
175whp and 132tq
Redzone tuned
There is no power up there. Theres no reason you need to rev that high on this engine. Mind you the a20 is not made to rev that high hence the redline.
I know on the 87 Manual it says the fuel cut is at either 6350 or 6500 rpm. The stock tach is not perfect and can be slightly off. One I hook up my laptop to my car there definately is a varyance between wht my ecu sees andwhat the gauge is displaying in the cluster.
Back to your question. If you really wanted to rev that high you'd need some good headwork with larger valves stiffer springs to compensate for valve float to go along with that cam you are thinking about getting made. Not to mention youd need to have to build the bottom end to keep it from grnading since you plan on running it to 7500-8000 on the regular.
The a20 dont ned to rev that high. The rreason the b and k series rev that high is to compensate for small displacement. The a20 was not made in that way.
If your looking for a good high end cam concentrate on something that gives best performance from 4500 to redline. Plus I dont know about your cars over there but over here the ecu cuts out the fuel at a certain rpm. If your cars ecu is setup like this also youll have problems reaching that 8 grand redline you want since the ecu will cut fuel shorlty after the engine sees red.
Go with the mildest cam you can find which concentrates on mixture and torque, e.g. Colt cams mild tri flow, then combined with some headwork, bit of a skim, exhaust Header, exhaust system, intake flowing, some TB mods, CAI matched to TB, Accel injectors, FPR, 4th Gen map sensor and that should be good for 150-170bhp depending on what head mods you do. The camshaft dictates howmuch the valves lift off the seats and for how long, this gives you a set powerband, but if you alter the efficiency of the head, this will increase the rpms even further as much as 1000rpm extra can be had form the same camshaft in two different engines e.g. a stock one and a heavily moddified one. I had an A18 head heavily moddified with Big valve conversion, revved to 7k rpm with a 272 degree camshaft, had an ET1 with same 2.0l internals same CR ratio, but this head had much nicer inlet ports evenly spaced out same bore spacing widths, but this only had stock valves yet this engine with the same camshaft was able to rev to 7.5krpm. Unfortunately never go to try the 285 degree camshaft as the rods broke and went through the block at 7.5k rpm!! So i guess thats the limit on those things!!
Stick with the above setup and keep the stock rev limiter and you will have a torque monster, as well as a lot of BHP especially if you have a big valve conversion done as well but your talking a reasonable amount of money but worth it.
In relation to what valve springs you should use if you did want to ever run 7k-8k rpm you would need valve retainers from ET1 head which are doubles, and then get yourself a set of exhaust valve springs for A20 Heads and use those all round with the internal double exhaust valve spring from an A18 prelude head. That's the best combo for around 7k-7.5k if you want 7.5k-8k or more then it would be 2G Prelude Exhaust double valve springs all round. If you wanted a good allround set of valve springs and easier to find then A18 ones are pretty good will go upto 7k-7.5k and you won't have to convert to double springs as they are singles on the intake side. I like having hte doubles but there not always needed.
This setup would be very similar to Mikes at Openloop and you should seee similar increases maybe a little less as he's pro but if you make 160-170bhp i'd say thats reasonable increase his is pretty well tuned and has a dyno to fine tune it which is why he's able to reach nearly 200bhp with his setup, obviosuly his intake and TB makes up the extra difference.
160-170bhp on a A20 is achievable without too much of a hit on the wallet but if you want to get more than that and have a redline over 7k rpm you will need some serious out lay to achieve that.
ya... misconseptions with the a20... one of hondas touqiest engines... tourqe is Bottom end...
the shift time on your accord when hauling should be about 5200 rpm...
yeah, sounds about right. maybe a little higher, like 5500. but yeah, when i run it to redline, it doesn't pull that much harder. although it does have the "vtec" kick in at about 3800. i'm serious. it's like my car switches over cam profiles like in vtec. almost dead then boom, power to redline. i'm inclined to believe it needs a good tune.
and maybe b-series revs high to make up for displacement, but the smallest k-series motor is the k20a. it starts out big as ours is and just gets bigger. they rev that high because they can flat out flow enough air to make power up there. that's why with i/h/e, new cam, hondata reflash, people are seeing 250+ whp in na k setups and they're still dd streetable.
Aside from the head, the other limitation is the stroke length. Engines with a long stroke just can't rev as high without flying apart. Stronger and lighter pistons and connecting rods will compensate for this but only to a point. Long stroke engines are good for low RPM torque. And low RPM torque is what most people want, not high RPM power. Low RPM torque is what helps you beat the guy next to you at the stoplight.
C|
haha thanx guys i think i understand now, hi reving a20=$$$$$
if i go for a tork monster, wots the hiest lift the stock valve springs can handel, as i can get a cam grinded for around 100 buks so just for now i wouldnt mind a bit of xtra power for cheap but once i get the money rolling in ill redo the whole head, and the rest fo the engine
fraza
dont worry mate, that'll buff right out
sweet man...torque FTW
1989 Honda Accord LX-i
B18c1 swap since 7/2011
175whp and 132tq
Redzone tuned
I have a stage 1 regrind from Colt. Seems pretty good at the low end.
STAGE 1 - PRIM INT 270° .384 LIFT
SEC INT 260° .384 LIFT
EX 274° .402 LIFT
These guys also have an A20 cam with a higher lift and less duration. I've never heard of anyone using one though.
http://www.webcamshafts.com/
Lift: .406/.430
Duration: 232/252
Duration at 0.05": 214/234
C|
do you run this cam with stock springs? or have u upgraded, coz i dont no where im gonna find a20 springs here in aus, or can i use some tuffer springs off a different stock honda engine?
dont worry mate, that'll buff right out
stock springs will be fine for mild slight wild grinds.
Alex.
They should be fine if you go with the mild cams, if your worried stock 2G carb prelude springs are good, also when you change your cam make sure you use new rockers unless the old ones are in very very good nick, you can re-surface them but you need to know what your doing off and also very time consuming.
I used stock A20 exhaust springs and stock A18 intake springs because they are a little stiffer, and I had them already. The stock A20 springs will be fine though. I think mostly you need new springs for much higher lift or higher reving.do you run this cam with stock springs? or have u upgraded, coz i dont no where im gonna find a20 springs here in aus
C|
+1 on the A20 coming alive in the upper 3K RPM range
if im gonna be aiming for a torky engine, should i bother with a b series manifold swap, or keep the a series, or is there another manifold, coz i no that the b series are tuned more for the hi revs, and i need a low tuned 1
dont worry mate, that'll buff right out
hehe noobie question...i cant find any cam gears for the 89dx searched for hours
yeah, that's because all those that exist are already owned. if you want to buy a brand new one, join the group buy we're trying to assemble. if you don't mind a used one, talk someone into selling one they have.
yeah the b16 manis are tuned for 7-10 RPM range....unless you can find one for low revs.
1989 Honda Accord LX-i
B18c1 swap since 7/2011
175whp and 132tq
Redzone tuned
i wouldnt mind a used one...
get new pistons-new valves-stronger springs...
the A20 is a long stroke motor, it is not good to over-rev it. Your bearings and rods will take a beating. I have also heard stories of the cranks in these cars snapping in half. I think 7000 is more than enough, you should work on optimizing power down low.
There is a fuel cut rev limiter on our cars but on the carbed motors the engine will over-rev due to the extra fuel left in the bowl after cutoff
Eric
3geez member since October 12, 2000
"All this worldly wisdom was once the unamiable heresy of some wise man." - Henry David Thoreau
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