max b.h.p. without forced induction?

[JMR_AW11]

Of the engines I quoted Raw did the 1st which gave me c. 145 BHP - can't remember how much it cost but it wasn't as low as £740 - some of that work was done by BJP (I think he's called Paul Jackson).

It was BJP and Mech in Cheltenham who did the next ultra expensive job - BJP did the head and supplied various parts like throttle bodies, cams, verniers and the OMEX and Mech set it up and mapped it, part of the cost being add-ons by Mech who claimed they had to do additional machining because BJP didn't quote or take account of piston clearance etc. properly. In fact the owner there was very critical of BJP and others who quote certain cams, lifts, durations etc. and then leave the builder to sort out issues. I was less than impressed by the time taken, delays and promises made/ not kept and the cost. I think quite a few of these people quote figures that sound good but wouldn't be achieved from some of the less comprehensive, quick add-on fixes they suggest - I'd like to see them proved and if they could, then would ask why they didn't achieve the same for me!

By the way, having read your last posts I do fully get your message and see where you were coming from, so stand corrected and don't want to rile you up!

It's just that I think anyone would be mad to spend say £1000 + on, let's assume, a bog standard Mk1 without starting with the chassis before the engine both for value for money and usability. If the suspension etc. is done then fine, just don't make the same mistakes as me

Then, as Paul notes - he didn't pay me, in fact I'll probably end up paying him! - getting a serious hike in power from a 4AGE is expensive and might lead to reliability issues, hence the defence of the sc engine or transplants

I recognise those names. I live near Cheltenham and I've been to Mech. The guy who runs it (Brian) is very down to earth and talks a lot of sense.

I helped him get his second rolling road running by finding some obsolete electronics parts for it.

I'm sure if we were all sat in a pub this mk1 MR2 tuning debate would have been 'smoother'

That's the trouble with text based discussion, you get one shot at making your point and it is open to scrutiny and misinterpretation etc and I've misread plenty of posters' views myself etc etc.

However, I do think there is a place for lowish budget 4AGE tuning and I'll be very interested in what Tom and Andy achieve on Tom's car.

I don't think anyone's going to compare it to an engine transplant for sheer grunt but if they do get useful figures and good drivability they could become mk1 MR2 heroes!

I understand that you are very track oriented hence your views on uprating suspension first etc. I agree with you on this but some road users will just want a bit more bhp as the stock car can be very flat to drive especially with two people and a full tank of fuel.

BTW are you the guy who sold the F plate track car (reg = F EAM?)
That car did look good and I bet it drove well on track.

[luthor1]

I've got Toms car at present and I've been road mapping it this evening with the wideband, it's all going fairly well and I'm just waiting for the 'inevitable' problem to happen!! For a 168,000 mile old engine, it's surprisingly youthful!

Can really feel the crap cams, and rubbish compression ratio in there!! Oh - and toms ultra-quiet 'straw' exhaust pipe!

don't worry Tom, she'll be running well soon! Already feels waaay better at the bottom end... and the T-VIS kicks in properly now after I got my logic 100% out on the programmable port, it was open at low revs and closed at high!! Hehehe

Once I've got a reasonable map on it, will take it up the Dyno and see what gives, then start to spend that tuning budget and see where we get.

Andy

[dgh.mr2]

JMR . . . it did seem that this thread had the potential to get a little contentious as Internet debates seem easily to do but I hadn't intended for my posts to make it less smooth, just honest and based on my experience. Guess I just love Mk 1s so much and have spent so much time on them I can't resist leaping to their defence!

The Mech reference is to the right company - God knows what would have happened if I'd just had the head sent back by BJP and got a local garage to fit it! Probably an immeadiate blow up . .

Yep, it was me who sold the car but luckily I have it back now sans engine and box so coincidentally am now trying to decide/ cost which will be the better option - to transfer the sc engine in and sell the rolling shell or to sell the car to fund a transplant, which is why the thread grabbed my attention. Paul's reference to the all alloy V6 is making me dither as it does sound v. tempting!

[LimeyMk1]

High comp HG, filter and exhaust resulted in:



As many know it resulted in the engine blowing a hole in a piston but could (and should ) have been easily prevented without too much loss of performance.

[JMR_AW11]

High comp HG, filter and exhaust resulted in:



As many know it resulted in the engine blowing a hole in a piston but could (and should ) have been easily prevented without too much loss of performance.

Sorry to hear about the holed piston (done this a few times on bikes myself)

The only comment I have on your bhp/torque curve is that it looks like the rpm scaling might be wrong (by >500rpm?) as it shows you have lost loads of torque by 5500rpm.

I thought that the stock engine gave peak torque at 5500rpm and peak power at 6600rpm so your plot looks different.

edit:
The other thing that looks odd is the dip assoc with the TVIS crossover. It looks to be at 4000rpm which looks too low by about 500rpm.

[luthor1]

Something doesn't look right in terms of the shape, but the 2 graphs cross (as they should) at 5250rpm!

Andy

[LimeyMk1]

The torque curve (which most interested me) confirmed the way it drove, pulled really well at lower revs all the way to redline.

A friend who owned an SC prefered it to his car.

[luthor1]

When raising the compresison, you'll speed up the burn, and hence require less timing which of course you can't modify yourself on the stock ECU.

If I compare the figures I use for ignition timing from the Saxo (10.6:1) -VS- MR2 Mk1 (9.4:1) there is a DRAMATIC disparity. Peak power Peak timing on the Saxo is 22 degrees BTDC, on the Mk1 it's 34!!!

I would imagine the high compression increased the efficiency of the engine/burn and hence it then required less timing

Andy

[cmux]

Paul's reference to the all alloy V6 is making me dither

My advice is don't dither.

[Bender Unit]

quote]Also, for £6,000 to only be making 8bhp more than the 5-valve engine in standard trim (with a catalytic convertor!!!!!)[/quote]

The 20v BT doesn’t make anything near the claimed factory output – 140 if you’re lucky. 150bhp with a remap and a conservative performance tune.

you see chaps Mr dgh here is living in the real world,gone out and spent the money it takes to achieve what you are talking about.Ok he maybe paid over the odds but all this talk of being able to hit 170bhp for £1000 is pure fantasy,quadruple that is much more realistic.

A lad on my forum has just made 133bhp at the rear wheels. Basically a stock engine with a filter, exhaust and manifold, 264 cams and a mappable ECU. Drive losses will be greater as that’s on a FR set up. That’s pretty damn good for the minimal money involved and all of those bits were second hand bargains.

[BarronMR]

A lad on my forum has just made 133bhp at the rear wheels. Basically a stock engine with a filter, exhaust and manifold, 264 cams and a mappable ECU. Drive losses will be greater as that’s on a FR set up. That’s pretty damn good for the minimal money involved and all of those bits were second hand bargains.

But how much would it cost the OP to reproduce those same figures??

I suspect £1000's...

Bargains are great but they can't be had by everyone, also did the guy do all the fitting and mapping himself?

[Bender Unit]

Second hand 4 branch - £200
Second hand cams - £300
Air filter - £25
Second hand ECU - no idea, doubt it was expensive
Mapping - again unknown wouldnt have been more than £400

Bargains are great but they can't be had by everyone, also did the guy do all the fitting and mapping himself?

TBH if the OP cant fit a set of cams, manifold, filter etc then he wont be able to swap an engine either so labour would apply for both options. Also all that stuff is readily available in the Corolla world - you can also buy new if you want.

[PW@Woodsport]

If we are talking costs of tuning and gains per £ then....

mk2 turbo rear clip £500
Other parts required £400-£500

Owner does all the graft as per above,total cost £900-£1000

BHP=220,raise boost with a £20 grainger BHP=250+

Fit a rev3 for say £500 more and you are touching 280bhp-300bhp for under £1500.

mk1 4age tune using 2nd hand parts roughly £1000 for 150bhp? = 28bhp gain,thats 0.028bhp per £ spent. (based on figures in this thread,presuming everyone can get such bargains)

mk1.5 using rev3 + second hand/new parts roughly £1500 for 280bhp =158bhp gain ,thats 0.1bhp per £ spent and you have 280bhp,not 150.

Even if you factor in the labour of a garage like us doing the conversion it works out at 0.045bhp gained per £ spent,almost double the value for money than if you did ALL of the 4age labour yourself.

End result....The 4a is a bottomless money pit with very little actual return in performance for your money,in my opinion of course and based on the calcs above

[dr_wilkinson]

The 20v BT doesn’t make anything near the claimed factory output – 140 if you’re lucky. 150bhp with a remap and a conservative performance tune.

I beg to differ; my totally standard 20v silvertop (even used the factory airbox in the boot) produced 149bhp - on a RR that I trust not to bull$h1t me on figures. Interestingly I tried a run using a TOMs ECU, which actually produced slightly less power and a worse torque curve on the rollers!

If you look at all the information on the web claiming that the 20v engines produce low power, it's usually from the States where they use low octane fuel, and consequently get nowhere near the same power from an engine as we would using 100RON.

As for the rest of the debate, it makes for interesting reading... Just wish I could make up my own mind over which engine to use in my track car!

Rich[/i]

[luthor1]

Second hand 4 branch - £200
Second hand cams - £300
Air filter - £25
Second hand ECU - no idea, doubt it was expensive
Mapping - again unknown wouldnt have been more than £400

Bargains are great but they can't be had by everyone, also did the guy do all the fitting and mapping himself?

TBH if the OP cant fit a set of cams, manifold, filter etc then he wont be able to swap an engine either so labour would apply for both options. Also all that stuff is readily available in the Corolla world - you can also buy new if you want.

Yeah that's about right!

Let's of course not forget that not everyone has the ability/time/space to fabricate a complete engine replacement, and let's further not forget that everyone's target is not necessarily the FASTEST that the money can buy. Personally, and I've said this a million times, I don't want a 250bhp Mk1, maybe other people do, that's great, but personally I love the 4AGE engine

It's not always about the money everyone! Sometimes people just want 30/40 bhp more than they have now and *don't* actually want to swap their engines over for another one!

Don't forget that for the cost of your Mk1 Turbo transplant fitted by somebody else, you'll be looking at the thick end of £3,000.

You can buy a REALLY REALLY nice MR2 Turbo entire car for that!

Oh - but people WANT a Mk1??? I hear you!

Well - maybe people WANT the 4AGE engine that goes in it too?

[Bender Unit]

With all said and done a mk1.5 does make good financial sense. If I didnt have the 86 I know what I would be doing Alot of bang for little buck.

beg to differ; my totally standard 20v silvertop (even used the factory airbox in the boot) produced 149bhp - on a RR that I trust not to bull$h1t me on figures. Interestingly I tried a run using a TOMs ECU, which actually produced slightly less power and a worse torque curve on the rollers!

If you look at all the information on the web claiming that the 20v engines produce low power, it's usually from the States where they use low octane fuel, and consequently get nowhere near the same power from an engine as we would using 100RON.

Sorry the ST or BT they don’t reproduce anything near the factory figures. A mate has run both a ST and BT in his sprint car both have been mapped using OMEX, both had a good 4 branch and exhaust system and meticulously maintained. The ST made 150bhp and the BT makes around 160bhp – these are conservative performance tunes as he wants reliability. That lad also has a 20v BT powered AE111 and has had that on the dyno and it only made 145bhp (totally stock). Being a mechanic both his cars are maintained to a very high level – his sprint car is better prepared than a lot of show cars I have seen.

In AE86 circles they have been fitting 20v’s for years now, and the majority view is they don’t make anything near what they claim as stock – you will need a few mods and mapping to get you around the 150 / 160bhp mark.

[dr_wilkinson]

As said above mine has been proven on a TAT dyno at 149bhp, so my personal experience is that the engine IS good for factory output figures.

There could be several reasons why others aren't getting good power from the 20v... If the ECU doesn't see a speed signal from the instrument cluster it loads a different map - does the AE86 cluster output the correct signal for the ECU? If not maybe this is the reason people are seeing lower bhp figures in these cars (with std ECU). I've also read of BT ECUs having problems with the VVT chip burning out, which would cause poor performance.

Why your mate is getting such low figures running on aftermarket mgmt I don't know (unless those figures are at the wheels?). The AFR on my standard ECU was way too rich from about 6500rpm upwards, and this is where a decent aftermarket setup should realise good improvements over stock figures...

[Bender Unit]

As said above mine has been proven on a TAT dyno at 149bhp, so my personal experience is that the engine IS good for factory output figures.

All depends on the tester and the dyno set up to be fair. A lot of places get it wrong. A mate had a dynoed 130bhp 4age – yet in a straight line dig I left him for dead with my pathetic 118bhp.

There could be several reasons why others aren't getting good power from the 20v... If the ECU doesn't see a speed signal from the instrument cluster it loads a different map - does the AE86 cluster output the correct signal for the ECU? If not maybe this is the reason people are seeing lower bhp figures in these cars (with std ECU). I've also read of BT ECUs having problems with the VVT chip burning out, which would cause poor performance.

Wouldn’t make any difference chap, these engines are running OMEX standalone engine management, the stock ECU is in the bin. The guy in question is a Yota tech by the way so knows the engines well and equally also says they never made the power they claimed from factory.

Why your mate is getting such low figures running on aftermarket mgmt I don't know (unless those figures are at the wheels?). The AFR on my standard ECU was way too rich from about 6500rpm upwards, and this is where a decent aftermarket setup should realise good improvements over stock figures...

Thing is those are good figures compared to what it would make stock. With a more aggressive tune he would potentially hit 160bhp but any more would require headwork (cams etc). Don’t get me wrong with that 150bhp it’s a quick car with a good amount bottom end as well. The general view is the stock figures are definitely over inflated

[dr_wilkinson]

All depends on the tester and the dyno set up to be fair. A lot of places get it wrong. A mate had a dynoed 130bhp 4age – yet in a straight line dig I left him for dead with my pathetic 118bhp.

Well I trust my testers and their dyno 100%, unlike the crap that emanates from most RR operators (I know there's one blacktop dyno printout online claiming that 91bhp measured at the wheels equates to 146bhp engine output...) - these guys mostly work on high spec race cars (for example XJRs and Moslers) and do a lot of tuning for the likes of for Noble and SBD. They're also using a TAT dyno, which is about as good as they come...

Wouldn’t make any difference chap, these engines are running OMEX standalone engine management, the stock ECU is in the bin. The guy in question is a Yota tech by the way so knows the engines well and equally also says they never made the power they claimed from factory.

My comments regarding the ECU and speed sensor were aimed at the other 20v AE86's and the totally stock BT you referred to earlier, rather than these two with OMEX ECUs. However, I would expect a well set up ST with aftermarket mgmt to output something in the region of 160bhp. Is the OMEX mgmt triggering the VVT solenoid, or does the engine have aftermarket non-VVT cams?

[JMR_AW11]

Second hand 4 branch - £200
Second hand cams - £300
Air filter - £25
Second hand ECU - no idea, doubt it was expensive
Mapping - again unknown wouldnt have been more than £400

Bargains are great but they can't be had by everyone, also did the guy do all the fitting and mapping himself?

TBH if the OP cant fit a set of cams, manifold, filter etc then he wont be able to swap an engine either so labour would apply for both options. Also all that stuff is readily available in the Corolla world - you can also buy new if you want.

Yeah that's about right!

Let's of course not forget that not everyone has the ability/time/space to fabricate a complete engine replacement, and let's further not forget that everyone's target is not necessarily the FASTEST that the money can buy. Personally, and I've said this a million times, I don't want a 250bhp Mk1, maybe other people do, that's great, but personally I love the 4AGE engine

It's not always about the money everyone! Sometimes people just want 30/40 bhp more than they have now and *don't* actually want to swap their engines over for another one!

Don't forget that for the cost of your Mk1 Turbo transplant fitted by somebody else, you'll be looking at the thick end of £3,000.

You can buy a REALLY REALLY nice MR2 Turbo entire car for that!

Oh - but people WANT a Mk1??? I hear you!

Well - maybe people WANT the 4AGE engine that goes in it too?

I think that sums it up pretty well for me. Some people WANT to tune the existing engine for a bit more power and then enjoy what is already a very enjoyable car/engine combo. I've had a stock mk1 since 1994 and I still enjoy the 4AGE engine every time I drive it.

What's the problem?