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4g64 dohc swap using two timing belt tesnioner pulleys

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darknezz7

Proven Member
571
80
Mar 30, 2014
Eugene, Oregon
So I thought I had the thread that I found this originally in saved but I guess not?

Went to put on the second tensioner pulley and it doesn't work like this makes it sound. The idler pulley sticks out the back while the tensioner one is inset, so the pulley edge sits against the metal.

What can I use here as a spacer?

This is what I'm talking about. 4g64 block with 4g63 head and cam gears using 4g63 timing belt and two tensioners.

"Best way is to use two tensioner pulleys. Replace the idler pulley with a tensioner pulley. Line the cams gear up to tdc like a 2l setup. Lock timing the belt to the cams gears using zip ties. Put the crank to tdc for number one cylinder. Tension the belt on the old idler pulley side first. Then do the tension on the hydraulic tension side. You can use a standard 2.0 timing belt this way. Plus the car will idle perfect this way. You can degree your cams from this point if you like but you might better off leaving it alone. "
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So how did he make that work ?

I want to be able to site where I got this pic and quote from too.

Thanks!

All I can find is this someone else mentioning the same thing... I'd like to find the original person that did this so I can site them in my build.
 
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I figure the easiest way to help you is to show you a picture of how mine is. Here's how its set up:
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Also are you using 4g63 cam gears? Your cam timing will be 1/2 tooth off on both if you do. You either need adjustables or 4g64 DOHC gears. Extreme PSI has them for pretty cheap.

EDIT: Oh I see, easy fix to the issue. Just get the 4g64 DOHC belt. If you look up the belt for a 94 Galant GS, it was an NA 4g64 with a DOHC head. I got a Gates belt for that for around 35 bucks. It fits perfectly. The 4g63 belt is too short and requires a lot of finagling to get to fit. I dont see any reason to do that when you can just get the correct one easily. Also I believe NAPA and other parts stores can probably order them, I got mine from Rockauto.
 
I seem to remember reading that original thread some time ago... I believe that the OP of it referred to using a 'stack of washers' and a longer bolt to make up for the difference on the adjustable tensioner in the stock idler pulley location.

I was interested in doing the same on my 2.4L 4g64 / DOHC setup, but just ended up using the OEM 4g64 DOHC belt & cam gears, as illustrated in bmxfelon420's post.
 
My specific question was "What can I use here as a spacer?"
Using stock 4g63 gears.

A stack of washers and longer bolt is what I thought of too but wanted confirmation.

Want to use 4g63 belt cause more common and can get the kevlar. It also says "You can use a standard 2.0 timing belt this way. Plus the car will idle perfect this way" so I should not have to adjust the cam gears.

We might end up doing the dohc belt if have to...

Thanks keep the info coming. I want to compile all this in the build.
 
Yeah the last time I entertained the whole 2.0L belt-on-a-2.4L block & DOHC head was over 6 years ago, when I first built up my 2.4, long before that thread even existed. It was rumored that it was possible and I would have researched the idea more if it wasn't for having other things to mock up at the same time. -Basically ran out of time before I had to stuff it all into the car and ended up settling for the OEM 2.4L DOHC method. Please keep us updated with your findings. I might revisit this on my next T-belt change.
 
Hey guys so there's something I've been thinking about and I thought I'd just ask. I understand the relation between a dsm and a evo, what I don't understand is how a gtr fits in this event yet a vehicle like a sti or srt 4 are excluded. Just something I was curious about if anyone has an answer.

My specific question was "What can I use here as a spacer?"
Using stock 4g63 gears.

A stack of washers and longer bolt is what I thought of too but wanted confirmation.

Want to use 4g63 belt cause more common and can get the kevlar. It also says "You can use a standard 2.0 timing belt this way. Plus the car will idle perfect this way" so I should not have to adjust the cam gears.

We might end up doing the dohc belt if have to...

Thanks keep the info coming. I want to compile all this in the build.

The OEM belt is hard to find, but the Gates belt is really easy. I'd be skeptical of the car having 100% correct cam timing that way unless you broke out a degree wheel and checked it. Yes the belt is the right length so it would move in a similar number of rotations as stock but there's 6mm of extra deck height that still figures into the equation. I'm not sure if someone ever checked valve and piston events using the two tensioner method but it wouldnt be a half bad idea. Especially if you have had the head, block, or both machined. That can screw up valve clearance and with a not 100% ideal setup already i'd be extra cautious with it.

Personally, i'm not worried about getting a belt. I can pretty much walk into any parts store and get one, and I dont think a kevlar belt is necessary really for a street car. They are nice though and I can see if you were running some crazy valvetrain that puts a ton more leverage or super high RPM itd be extra insurance.
 
FWIW, ExtremePSI has always had 4G64/DOHC stuff in stock... it's where I got my OEM 2.4L T-belts & cam gears:

http://www.extremepsi.com/store/home.php?cat=865

bmxfelon420, you share a lot of my same concerns while I was building mine & (ultimately) why I ended up just going with the OEM 2.4L setup

Yeah I remember I almost ordered it but couldnt justify 92 dollars for a Mitsu OEM belt when the Gates is as good or arguably better quality wise for 1/3rd the price. Not hating on OEM in any way, but I've been on medical leave AND assembling a car. A bit of a tight budget here.
 
Yeah I remember I almost ordered it but couldnt justify 92 dollars for a Mitsu OEM belt when the Gates is as good or arguably better quality wise for 1/3rd the price. Not hating on OEM in any way, but I've been on medical leave AND assembling a car. A bit of a tight budget here.

I hear yah... Those were better times for me financially back then. Gates does make some good belts! -That's the only brand of accessory belt(s) that I haven't shredded and/or thrown off the car yet! But when it comes to timing, I'm old school... OEM-only (seen too many others fail prematurely).
 
Ok well I'd still like to try and use the 4g63 belt if I can get some solid answers on it.

But for sure I can use the 94 galant dohc belt and stock 4g63 cam gears just remark them.
gates # T256, its $65 at oreilly

Good info
 
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Interesting. The only thing i'm wondering about that thread is if the evos have a difference in their setup that allows them to swap like that. Also, you wouldnt use the timing marks on the c
Ok well I'd still like to try and use the 4g63 belt if I can get some solid answers on it.

But for sure I can use the 94 galant dohc belt and stock 4g63 cam gears just remark them.
gates # T256, its $65 at oreilly

Good info
Yeah as I understood when I was researching the swap before I bought anything using the 64 belt with 63 gears screws up timing. If I understand this right, the 63 belt with 63 gears will be correct. Im not sure how much timing one tooth is but i thought each cam would be off by an amount not doable by a whole tooth. (with mismatched belt/gear combo)

The easiest way to think of this is as a big circle. Consider your cams to be "orbiting" the crank. On the 64, they orbit 6mm farther, which is why the cam gears are different. by keeping the 63 setup and belt length you are essentially pulling the "orbit" back in. The only concern id have really is valve clearance. If youre in spec, Id say go for it. You have to be careful with the higher piston speeds when it comes to that.

In any case, try the washers as suggested earlier and let us know if its in time. Maybe you could make a solid spacer for it? Id like to see how it turns out.
 
The block and head have been surfaced and it has oversized valves... Definitely dont want any tapping that would be horrible.

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the forum is freaking out giving errors and not working right all day or my computer....[DOUBLEPOST=1408766746][/DOUBLEPOST]
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The block and head have been surfaced and it has oversized valves... Definitely dont want any tapping that would be horrible.

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the forum is freaking out giving errors and not working right all day or my computer....[DOUBLEPOST=1408766746][/DOUBLEPOST]
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Ah, in that case you're going to want to check that for sure. Any difference in angle/size will need to correspond to the valve reliefs in the piston, to prevent very bad things. Check into that for sure no matter what you do. I didnt worry about it in my build because I somehow managed to get a block and head that didnt need machined at all. Also with stock cams and a thicker than stock head gasket (just because its MLS not to bandaid the issue) I'm way on the wide side for sure.
 
Its stock cams for now and a thicker than stock mls also.

I already torqued it down, the clay between the valves to measure is out then? I'll have to do some more research. This is my first CUSTOM build btw.
 
Great vid, wow I really need one of those valve spring tools!

There's nothing I can set it at where it would be on the safe side and still run good?
Really just trying to get this back together and driving right now, all fine tune adjustments and power will be later.

I do not want to put it under any hard running conditions though and ofc definitely don't want a chance of valves hitting...

If i got the 4g64 dohc belt would I not have to worry?

Oh I found this again, great instructions and pictures. Looks like it can be done with the head on.
But I also need the degree tools and adjustable gears it looks like..
http://www.4g63turbo.com/tech/4g63-camshaft-degreeing.html.

Might be time to get those tools and learn this anyway.
But I also see "Although, I've never seen it being a problem on a DSM. Most aftermarket piston manufacturers cut the valve reliefs quite generously so unless you're running some outrageous duration cams you seldom have clearance problems but still checking the piston to valve clearance is highly recommended."

It does have wiseco pistons with big reliefs, stock cam and thick mls head gasket. I'm thinking it will be fine but would like a simple way to check or confirmation of a timing procedure proven to work in this situation.
 
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Most of the stuff to do it can be bought at Harbor Freight and be fine for that purpose. I'd agree that the aftermarket reliefs are larger, but the wisecos have more compression than stock pistons too so they will have less of a dish. You may be ok, but there's also a chance you may not be so I'd try to check if you can. If the amounts milled off of your head and block+head gasket thickness are greater than a stock uncut head/block+stock composite HG, theres more of a chance of it being ok. The only thing that I'm unsure of personally is the oversize valves. On my build I have an unmilled block, super light milled head (did not do a full surface cut into the head), thicker HG and stock size valves and stock cams. I will check it when I do a cam upgrade just to be sure though.
 
So I need one of these to measure cam lift?

I don't see a degree wheel but will keep searching or maybe order one.

I was hoping to get the motor timed up by now and not have to do all this fuss, its all a learning process for me though.

Thanks for all the help
 
I was just looking, Ill just print and laminate a wheel.

the http://m.evolutionm.net/showthread.php?t=615476 is a great thread once you sort through the crap.

The correct answer to this is, either belt will work and to just properly degree the cams no matter what combo because everyone's is different so there is no one answer fits all.

Now I can still do this with stock 2.0 cam gears right? just have the slack on tensioner side, degree cams and then tension.

Thanks for all the help! I will pick up a dial indicator plus stand for it and do this right while learning something very important for custom engine building. Need to know info for future cams and builds anyway![DOUBLEPOST=1408852914][/DOUBLEPOST]Oh, is it absolutely necessary I do the solid lifter mod to have zero lash since I am NOT using a aftermarket cam?

as stated here http://www.4g63turbo.com/tech/4g63-camshaft-degreeing.html

I have extra lifters and can do so if needed.

would be nice to just degree and time it up as is and go though!
 
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You have to keep in mind that when degreeing if your cams require adjustment you can only adjust in whole tooth increments with stock cam gears, which are something like 3.75 degrees? I'm not 100% sure but you wont get it exact that way. If you have stock cams, and stock gears, just line up the marks and test the valve clearances. You need the solid lifter in what youre measuring so the measurement is accurate. Degreeing really only comes into its own with aftermarket cams, so you just need to test the clearances to make sure you're not below spec.
 
Thanks, that's exactly what I needed to hear and what I concluded too. Yeah each tooth is 3.75* so I realized I wouldn't be able to fine tune it. I do want to learn this now though so I'm going to go ahead and get the dial indicator and check it out. Will get some adj cam gears in the near future.
 
I'm finishing up a 4g64 with a 1g DOHC head, and I'm just trying to figure out the extra stuff. I was wondering what timing cover you guys used. My first thought was the 1994 Galant 4g64 dohc timing cover, but I can't be sure on the part numbers and everything is showing discontinued.

Holy hell, I just realized this is a 6 year old thread....
 
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