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Discussion Starter · #1 ·
Ok i recently was at redline in 3rd gear and made the biggest mistake ever - went to snap 4th and went to 2nd - well it over reved and bent 5 exhaust valves. So i went to a import performance shop that i heard did great work from a few ppl and gave them my head - this is what they did to it - full port & polish job, multi angle valve job, polished combustion chambers, Milled the head 11 thousandths i think they said, 0.5mm Skunk 2 oversized valves, Skunk 2 Ti retainers, Skunk 2 Dual valve Springs, also port match my intake manifold. My other Mods include MSD 6-AL - Cold Air Intake, 4-2-1 Header, Stock cat with 2.5" custom pipe to HKS universal - Fidanza Flywheel and Unorthadox Stage 1+ windowed kevlar clutch -

Ok my problem is that almost everytime I stop at a red light or whatever it wants to idle real low and most of the time is quits on me - my compression reads 145-140-140-145 which i know is very very low - Could my cams be out of time??? - I know the problem doesnt lie in the valves cause the head was put on a flow bench prior to installation and it flowed 56 cfm more than stock - Whatever the problem is - is also causing me to run very rich and i have more power from 4500 to 5000 rpm then when vtec kicks in at 5000 - when vtec kicks in at 5000 it actually bogs down and i feel a drop in power and it takes a very long time to actually get to 5500 - Any Suggestions?????
 

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Did they compensate for the altered timing when they milled the head?

When you mill your head, you throw off your cam timing and have to compensate for it. Since you didn't mention it, that's what I'd bet on.
 

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with all that work you should of put some cams in there too

those compression #'s look really low
 

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What type of port job did you have done. I hope its not a racing one those cfm numbers look high. IF you port too much out of the head it can slow the speed of the air coming into the combustion chamber which can cause the bad idle. Once you mill the head or add a thicker head gasket the only way to get the timing of the cams back to TDC is to put some cam gears on it and adjust them back to TDC.

If you got the Ti retainers and the springs why not cams themselves. I don't know that it would help you problem but it was kind of pointless to do all that other expensive work and NOT get cams.

Another thing, did you check your compression with the fuel pump fuse pulled and the throttle at WOT and while the engine is warm? Those compression numbers are really low if you did do those things while checking and have a milled head to bump up compression.

Double check everthing that you did when you installed the head back on the car. its possible that something was forgotten or messed up. Has the car always run this bad once you got it back to running? Do you have a VAFC?
 

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Discussion Starter · #5 ·
well the money that went into the head was saved up for a turbo kit when i accidently ruined my motor - i havent gotten around to getting cams yet b/c im still saving for turbo kit - but i did just buy a set of STR cam gears and hope to get them on soon - so the head is milled then which way would i need to adjust the cam gears to get the cams at correct TDC??? - Also the car has been running like this since the head work it self
 

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Discussion Starter · #6 ·
Im putting the cam gears on this saturday but how should i adjust them - im pretty sure it was milled 11 to 13 thousandths?????
 

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If they head was milled only that much you shouldn't of really got a perforance hit. It's only a degree of timing that you should advance the cam gears. Have you tried to adjust your idle? I'd go back to the tuner and ask them regarding the compression numbers since they should be in the 180-190 area especially with your increased compression.
 

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Discussion Starter · #8 ·
Then what is causeing the power band to be before vtec when it hits??? i get more power from 4500 - 5000 then i get when vtec hits at 5000 - - - from 5000 to 5500 i actually feel it boging down and losing major power - dont quote me correct on how much the head was milled but what is my problem????
 

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.011 mill probably isn't enough to throw your timing off that bad. with the oversized valves you should be looking at some 10.8:1 or so compression which would mean you should be blowing like 215psi or so.

Something is WRONG with the valves seats or the head gasket or something compression of 140 is very very bad. You should focus all your attention on why your compression is horrible. That is your main and most serious problem.

Oh and just as a note you never verified that you did the compression test correctly...WOT, fuel pump fuse out, warm engine.
 

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vector4 said:

Oh and just as a note you never verified that you did the compression test correctly...WOT, fuel pump fuse out, warm engine.
thats what I'm thinking, it is a common mistake and should be double checked.
 

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The power jump has to do directly with the head work. If your really flowing that much more air, you're going to need to adjust the fuel timing. After all that work, you really need a vafc and a dyno (or a standalone ... but thats a bit much i think for na). The cam gears (from what ive been told, i cant confirm or deny it) move the power band up and down. So having bad cam timing would move the power band down or up. However, i'm also thinking that because your fuel curve is off ... your hitting the stoich point 'sooner' than before .. (your getting more air sooner so your power band is shorter ... burning that same amount of a/f with less effort). I'd really take it back to the shop you got it done at and complain. Make sure to ***** about the numbers ... and make sure to ***** about not fixing the cam timing.
 

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Discussion Starter · #13 ·
ok did the compression readings and just as i thought - it read 160 - 150 - 150 - 160
i talked to a local tuner shop and they said that the cam gears being off in the same direction could be affecting the power band and the compression like so - im hopefully getting the cam gears on tommorow but i hope everything goes well - which way should i tune the gears to go back to original TDC - and any tips on the belt removeal , installation - going with helms manual but i hate that auto tensioner - ANY TIPS PLEASE
 

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They're BSing you. The cam gears being off by 1 degree doesn't cause compression to drop. Are you doing the compress test warm and with the throttle body full open? You want to advance the cam gears 1 degree.
 
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