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Location:
adelaide
Registered:
May 2002
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 Slightly modded 18R-GE - What cams would be best?
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Tue, 20 January 2004 15:55
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Hey, all u 18RG owners, what pistons/cams do u run??
ive got an 18R-geu with 88250 bottom end and pistons(i think???they have smallish domes with flycuts for the valves) and 88270 head with standard EFI gear, surge tanke etc..
I have 88270 cams in it at present.
Do you think there is much more potential for this engine with more aggressive cams? I think it has slightly earlier pistons in it, unless someone can confirm 18rgeu 88270 pistons having domes. so would this warrant putting the 88250 cams in the head?
Does anyone have the comparative specs of the 88230, 88250, and 88270 cams??
Is it worth me buying a set of 88250 cams and trying them?
what benefits/drawbacks would i expect to experience, considering my head is EFI not carbie?
Because i am probably getting the motor dynotuned in the near future and i'd rather get it tuned for the best cam setup, as far as power and all-round drivability is concerned.
Thanks for your advice and comments anyone,
Cheers
Guy
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blackRA28
[Updated on: Tue, 20 January 2004 15:57]
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Location:
Adelaide
Registered:
June 2003
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Re: Slightly modded 18R-GE - What cams would be best?
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Wed, 21 January 2004 03:34
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We are currently running 88251 cams, but are getting another set of those cams reground to a genuine toyota mild permormance setting, should be somewhere around 270 degrees at .1mm lift (280 degrees total duration) I don't know the specs for sure. 10.5mm ish lift too.
THis is costing $120 for the pair, but is not a cosworth (welded) type regrind, so new shims will be required, but at $5ish each, its no big deal.
We are using these with 9.7:1 pistons with a mild port polish 88270 head and old style 40mm solexes.
The carbies will probably be a restriction, but regency are not our friend, so an efi conversion is off the cards.
DO NOT TELL REGENCY that you've got efi gear on a non efi block, it will cost you thousands to get it legal.
Just tell them that the whole lot is EFI, and hide the computer behind the glove box and say that its all 18rgeu gear if it isn't.
Anyway, I've been told by someone who seems to know what he's talking about that changing cams with an AFM set up screws with the efi big time.
The AFM and computer don't cope with anything other than stock.
You could go for a UNI chip type thing, which can be used as a piggyback to your stock computer to readjust it to suit the change.
The better option is to go for a MAP sensor set up, holden (yes, yes, I know  ) camiras have a MAP sensor and can be used for an 18rgeu with better cams.
With low compression pistons, higher duration cams may lose quite a bit of bottom end benefit. usually, from what I've noticed, people take the compression up as they take their cam dration up, that way they don't lose too much active compression (and bottom end) while reaping the top end benefit of the higher duration cams.
If anyone think's I'm wrong, please correct me.
Guy, if you want any 18rg help, don't hesitate to PM me, I'll give you my details on request. We've rebuilt one of these suckers, so we know a little bit about them now.
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Location:
Adelaide
Registered:
June 2003
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Re: Slightly modded 18R-GE - What cams would be best?
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Wed, 21 January 2004 03:37
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Also, 88251 cams appear to have the same lobe details as the 88270.
There may still be some 88250 (non adjustable sprockets) cams at Just Wrecking Toyotas near Wingfield.
They may not be 250 cams, but they were in a 250 head.
Anything after 88250 had adjustable cam sprockets.
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Location:
adelaide
Registered:
May 2002
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Re: Slightly modded 18R-GE - What cams would be best?
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Wed, 21 January 2004 05:56
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No worries Steve, thanks for that it was a lot of useful advice and info..
Im now uncertain what path to take the old 18Rgeu, on the search for more power.
If i went to regency i wasnt going to tell them about the internals! when i bought the motor i was under the impression that the motor was a complete stock 18R-GEU, but only after finding bent valves we noticed the domed pistons. I am not sure where they are from, but while looking at the lower part of the timing cover there was an -88250 stamped in it which leads me to beileve it is an 18R-GU(88250) with the efi(88270) head. still uncertain.
All the EFI is Factory 18RG apart from the AFM(22R-E), and fuel pumps. Analog fuel-only ECU, electronic dizzy, and spring-type flap AFM.
Hmm maybe i wont mess around with cams at present, better to keep it as economic as i can at the moment anyway. I may continue and save up for a custom turbo kit map sensor etc, but it may end up costing more than an S15, GT4 or similar front cut... 
One reason i brought up this topic is because my car suddenly died whilst driving at low RPM a couple of weeks ago, was at about 2000Rpm in 4th and then POP! out the intake side.. ecu auto cut off.
Couldnt work it out because was still getting plenty of spark and fuel, just wouldnt start and sounding foul.
Once home took off rocker cover and crank, to find that the exhaust cam is not turning!
Steve, u may be able to remember the short timing pin/dowel that aligns the cam to the cam gear, This small pin either snapped or dislodged itself from the press fit. But i fail to see how it could have moved or fallen out becasue the large washer on the front of the cam gear covers it almost completely.
We have tracked down another dowel which will probably fit, but im just hoping no other damage would have been caused to the block/internals.
Did you use new valve springs in your rebuild Steve?
anyway,
thanks again for the advice!
keep u updated on how it goes,
Guy
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Location:
nth ringwood, Victoria
Registered:
August 2002
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Re: Slightly modded 18R-GE - What cams would be best?
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Wed, 21 January 2004 05:59
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black ra28 i have a full TRD motor thats fresh has trd valves springs and retainers plus forge pistons and trd billet cams the pistons are 10 .2 to 1 the haed has been done plus it has new chains and guides it needs carbies and manifold plus extractors to get the best out of it i wont 2000 for it thats a bargain and all thats been done to it was run in on the dyno
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Location:
SYDNEY
Registered:
August 2003
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Re: Slightly modded 18R-GE - What cams would be best?
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Wed, 21 January 2004 07:53
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I have an 18rgu with all the geu efi gear. So 8.7 comp pistons would be in it. A 88250 head and I use the 88750 adj cams. I get 400 to 450 lit/100 kls so its not to bad as a daily driver.
Though when I put the better cams ie.88231 cams 145 hp 18rg earlier cams it revved very high with no power until the 6000 rpm range.Where as the 88750 you get lower toque and better daily driving. So I swapped them back and put them in the cupboard. I have extractors, new internals. So to suggest to you not to change cams at this stage, you should have a nice fairly smooth ride, add perf cams start revving. Thats my experience.
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Location:
Adelaide
Registered:
June 2003
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Re: Slightly modded 18R-GE - What cams would be best?
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Sun, 25 January 2004 04:31
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I know why you're valves went then Guy,
those little pins/dowells in the cams the hold the gears on are NOT pressed in.
They are free fitting, and by realigning and mixing and matching holes in the cams and in the gears, is how you adjust the cam timing.
There is a washer with one flat side on it, the flat side is there so that the peg can be removed to adjust the timing, once timing has been set, the flat side of the washer MUST be pointed away from the peg, ie., 180 degrees around the cam from it.
That washer that was almost covering all of it, should have been covering all of it, that is the only thing that holds the dowell in.
replacement dowells are easy to find, one of ours is the shaft end of a drill bit, that shouldn't snap in a hurry and they come in a variety of diameters, so you can pick the right size.
Yes, we sourced new valve springs, we went for Performance Springs part no. RR4 sourced through TW Engineering. From reports, they should be good to 9000 RPM.
As far as turbo goes for these conversions into an RA28, yes, it will cost more than a half cut, for sure.
You may be able to get it running for less, but the emissions test to get it legal will cost you thousands in SA, it is reportedly cheaper to drive to sydney, get it tested there, then drive home.
I hate bearing bad news, but a car made after July 1976 is a real pain in the ARSE as far as legalities go.
Keep me up to date with any progress or problems, I'm always interested to know stuff about these engines.
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Location:
Adelaide
Registered:
June 2003
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Re: Slightly modded 18R-GE - What cams would be best?
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Sun, 25 January 2004 04:48
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I forgot to mention a few things.
the casting gen. number on the timing case doesn't mean a whole lot.
Our 18RGU (came with a 88253 head and 8.7:1CR) came with an 88230 dizzy and a 88210 timing case.
I have seen an 18rgeu with a 88250 timing case before. All it means is that they didn't have a need to redesign the timing case from the 18rgu to the 18rgeu.
I have never seen a 88270 timing case, so I don't know if one was ever made.
All 18rg/u/eu pistons are domed, just to different heights.
The 8.7:1 domes are about 4mm tall.
The 9.7:1 domes are about 6-7mm tall.
The 8.3:1 domes are lower than the 8.7:1
Omegaman, I'm not too surprised that you didn't get benefit from the 88231 cams. The 8.7:1 CR pistons aren't suited to that cam profile, you would have lost more active compression when those cams went in, and starting with a low CR, this is quite likely to have a negative effect on performance, and especially low down torque.
The lack of adjustable cam timing would not have allowed this issue to be partially over come through the timing adjustments possible in the later model cams.
It's a real pity that the cam swap didn't work for you and I can see why you would have switched back, the bottom end torque of these engines is a huge benefit over their 18rc cousins.
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Location:
adelaide
Registered:
May 2002
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Re: Slightly modded 18R-GE - What cams would be best?
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Wed, 28 January 2004 13:16
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Thanks again for the info and advice Steve, i will keep you posted on how it goes when i get it running again, and ill definately chat to you if we run into issues..
CelicaRA45 that sounds like a ripper of a motor and if its still around in about 8 weeks i mite buy it, but at present my lack of spare funds restricts me.. I am saving tho, just got a new job!
But why would you be selling such a good motor, it obviously was expensive to build and you didnt even put it on the road? were the dyno results not what you had aimed for?
what carbies was it using?
Could you inject this motor or would that pose a restriction compared to webers/quads throttles say?
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BlackRA28
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Location:
Adelaide
Registered:
June 2003
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Re: Slightly modded 18R-GE - What cams would be best?
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Thu, 29 January 2004 03:20
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I dare say that you'd have issues getting that past an emissions test.
You'd most likely have to run an atfermarket programmable computer and probably a MAP sensor set up, Webers on a motor like that would go through the fuel something fierce, and the EFi would give better midrange, which is always better if you've got an engine that has had cam work.
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Location:
SYDNEY
Registered:
August 2003
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Re: Slightly modded 18R-GE - What cams would be best?
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Sat, 31 January 2004 13:13
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Steve m
I'm glad there is a reason for the lack of power when I changed cams,i don't feel so confused now.I guess I now need some new pistons 9.7.1 or just use the cams as paper weights.
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Location:
Melbourne
Registered:
October 2003
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Re: Slightly modded 18R-GE - What cams would be best?
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Sun, 01 February 2004 02:39
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i've got an 18rg how do i know if's a U aswell? Its got carby's
fitted. Is there an easy way to tell what pistons i have? like a model code which means "this bottom end was released with 8.7:1" or even for the head which i could see if it's a E head?
There's lots of scrappy information around, but i suffer from short term memory loss, so if someone could put it straight for me in one chunk it'd be good.! thanks.
Also, what can the 18rg rev to safely, and whats it rev to to make power.. mines does power to about 6500. but still has good bottom end torque so i think is standard. Whats the potential of these engines with a good porting job, high comp pistons, and a matched set of perf cams? (ie, anyone dyno'd or put one down a 1/4)?
Thansk
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Location:
Brisbane
Registered:
October 2002
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Re: Slightly modded 18R-GE - What cams would be best?
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Sun, 01 February 2004 06:00
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| Quote: |
> Here's some head numbers off Al's 18RGs:
>
> 88250:
> - 49657 single spring early rgu single dump ex ok head small studs on ex
> - 52978 same as above
> 88253:
> - 73086 double spring late rgu good head to start with large studs on ex
duel dump man
> - 62744 single late rgu still good head may be small stud ex should be
single dump
> - 81784 double spring late also
> - 87278 double spring late also
> 88270: these are ale efi heads all double springs alll good heads these
are the ones you use
> - 35140 biggest ports biggest valves no smog ports best casting
> - 08037
> - 49383 very late head newest ive seen
> ?:
> - 81225 same as above double late rgu if the head is a 11111-88253 not a
11111-88270
> 88253 88270s would be the heads of choice since these need very little
work from the factory these willl make lots of power with little porting
they will make a lot more power with a lot of porting the castings are a lot
thicker around the ports so there is a lot of room
the 88250s can be made good but the ex studs should be changed up to 10mm
ones for best sealing
all of these engines should have 8.5s to 1 but the efi 88270 heads they
should have 8.3 to 1
just be glad you dont have any of those 11111-88230 or 88210 heads they are
good paper weights
hope this helps your info of what you got there sounds like my garage
i think i have 15-18 heads right now
cary
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my 18RGU makes power to about there too, maybe with mild porting, mild cams and the 9.7:1 comp u may get about 170 odd,
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Location:
adelaide
Registered:
May 2002
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Re: Slightly modded 18R-GE - What cams would be best?
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Mon, 02 February 2004 13:33
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mine runs stock 18rg ECU and efi setup with 22RE afm, 18Rgeu head cleaned up, still not sure about the pistons could be GU or GEU, but it goes like hell, excellent midrange power and all round bottom end torque, but it can just rev out to about 7500 still picking up and sounding fine, i think the rev limiter or fuel cuts slightly up there so its lucky its not even tuned and running a bit rich...
i have kept up with a 13B Rx-2 with 85 kw@wheels from a rolling start without pushing her too hard, so i want to know what kW it puts down at the wheels once back up and running again.. 
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