ROLLER VALVE LIFTERS??????

mini freak out. I have my head off this weekend to replace the head gasket.

I have had lifters on the shelf awaiting this moment but the ones i pulled out are very different.

Attachment 1841

On the right is the one I removed. SUPRISE: its a roller, and the oil hole is in a different spot.
On the left is the one that is supposed to fit. Summit Racing: SUM-HT951.


It could be a bad cross reference. I picked it up from an african Hilux forum studying performance 4y options. They believe the toyota lifters are crap and have switched to a hi-revving chevy replacement.
http://www.hilux4x4.co.za/views/viewtopic.php?f=3&t=3858

How did a roller end up in my engine???? I'd love to run a roller, I just don't want this be the cause of my valve train tick. Any one who is a Racer will know that the highest point of friction in any motor is between the lifter and cam. Any one who had driven a van will know a know it needs all the help it can get in terms of power.


ANY WHO.....

Can any one confirm dimensions of a stock lifter?
Dimeter?
Length?
Distance, Flat end to oil hole?

Thanks!!!

That blows my mind too. Finding roller lifters in one of these is very interesting & I suspect somebody would have gone to a lot of trouble to make these fit/function correctly. Is this a roller on a solid lifter, or is it some sort of hybrid roller/hydraulic? Either one would blow my mind because I'm not aware of any such hybrids & solids would need to be adjusted periodically. Were there any mods to the rockers to make them adjustable?

Another point of interest is that roller lifter looks to be too tall. Does your engine have custom length push rods? (stock length is roughly 6 3/8"). As interesting as this mod is, unless you can figure out and deal with the adjustment issues, I would probably go back to stock. Of course this would mean a new camshaft, new lifters and likely a new set of push rods. Fortunately OEM push rods are still available & are actually cheaper than aftermarket (at least they were last time I checked).

As for stock 4y measurements, I have a few sets of well used OEM 4y lifters and a couple sets of new Enginetech #L6005-4 4y lifters. Taking rough measurements using a 6" caliper I read the same on both (used OEM & new AM). Dimensions are .842" outside diameter & 1.998" overall length. I didn't measure down to the push-rod surface, but they look to be identical. Distance from cam end to oil hole is 1.360" on OEM & 1.380" on AM. Tim

PS: I checked that thread you linked to, but could find no mention of a performance mod using chev lifters.

the rollers are hydraulic. I have them soaking in kerosene in hopes to rehabilitate them until i have my hands on some thing else.

2.600" tall
0.84" dia
1.785" cam to oil hole

push rods are stock. AND not bent.

sum-ht951 lifters match the stock dimensions.

I'll talk to my engine builder when i pick up my head up tomorrow about the conversion.

I wonder if THESE would work? Same diameter, but nothing about length. On your roller lifters, is the push-rod surface inset down low in the lifter? How about a picture from the top? Tim

I think the summit rollers you posted look like mine.

Measureing the depth of the cup on the push rod side is tricky.

Summit HT-951 = 0.274 lip to the bottom of the cup.
Mystery Roller Rocker = 0.284 (but it uses a larger hole so the caliper drops in a little deeper)

Below are The rollers installed in Cyl 1 at TDC Power Stroke. It looks SOOOO stock. Are you sure the 3y didn't use these? My bottom end is a 3Y.
Attachment 1842

Now here are the summit HT951:
Attachment 1843

They sit MUCH MUCH deeper in the bore.

Is push rod length the same on a 3Y?

Which one looks right?

I never really messed with 3y's & don't know if the deck is higher on a 4y block, but if it is, then the 3y push rods would need to be shorter. I used to mess with high performance chevs back in the 80's and ran roller cams, but the lifters I ran were always solid (with roller on the bottom). Until you posted I didn't know you could even get hydraulic roller lifters :dizzy:.

Anyhow, this is interesting. I do know that KC has had lifters out of his 3y (posted pics are somewhere) and his were the standard old flat bottom lifters (no rollers). Might be worth pursuing a mod like this, but since standard stuff is cheaper and seems to last well past 200k miles, I think I'll stick with what I know. Keep us posted with what you find out. Tim

PS: I measured a 4y push rod and it comes out right around 6 3/8" long

I'm stuck between what is "supposed to fit" (hydraulic tappet) and What it ran with (hydraulic roller), albeit noisy.

I'm tempted to go with what i knew worked in the past. Hydraulic Rollers.

I'll see if someone can match the dimensions and get new rollers.

Did you notice the retainer that keeps the roller from twisting in the bore?
Is that tapped hole in the block for the bracket always there???

A flat tappet does not need that and is made to rotate in the bore for even wear.

Yeah, I noticed it & that also threw me for a loop. I'm now thinking this has to be a stock set-up for this engine, but certainly not anything they did for the US market. I'm guessing that engine was built for a different market & imported here. I just took a look at a bare 4y block I have sitting here and the casting is different. There is no metal in the location where that bracket is attached, there is just a large (about 1") oil return hole there.

Based on this, I'm thinking I agree with your decision to try & find new roller lifters. If info isn't available I'd probably order 1 of those rollers from Summit and compare. If it's the same, then order another 7. Tim

Is this possibly a newer JDM replacement block? Isn't the 3Y more common in other markets? Maybe this was a factory upgrade after they stopped production for the North American market.

http://forums.justcommodores.com.au/...-ecotec-2.html

About halway down the page someone says that sbc hyd rollers fit 1y2y3y4y

So what kind of performance parts can be put into a 4y to up the rpm limit as well as increase top end power? I maybe able to fix forklifts but i know nothing about engine performance

Gushaman, I'm of the opinion that it's best to stay stock on these. High performance mods usually boil down to compromising reliability and economy for more power. If you had an OEM set-up like coronan (roller lifters), then I'd try to keep it that way. If you have a big budget and lots of time, making high performance changes might be an interesting project, but then if you had the time/money, why mess with a 4y? Tim

If your going to change the topic, dont hijack, please start a new thread.

I agree with Tim. I have done much reading. The Africans and Australians have aftermarket support for the 4y. Maybe 120hp unless your go to forced induction.
There are $1000 of mods i would like to do to my 4Y.... But I think my money would be better spent on a swapping in a VW TDI.

I know a guy who put one in his Tacoma and is getting 33mpg and has just under 200 hp.
Search: TDIclub.com

If you want to tinker with the 4y because its what you have.....
Study these sites:
http://brianlawson59.blogspot.com/p/efi-conversion.html
http://www.hilux4x4.co.za/views/

My best Mod for drivability so far has been 4.88 gears in rear diff coupled to the 5 speed. I can cruse any speed I want on flat. I have 30" tires. My RPMs are about 3500 @ 75mph. MPG's went up. I get 22 mpg.

My bad, wasnt meaning to hijack. Asked an old timer at my dealership about thos today. He said yes he has seen the rollers in 4y engines from south america. He wasnt surprised about the push rod length either. He said the bores for the tappets may be slightly different. He said that while north america only saw the 4y installed in forklifts after 1989, in south america (most likely africa and australia as well) tjere were "performance versions" that were supposed to good for maybe 50 more horsepower. He has seen them in used s.a. engines he imported