[Mk2] [Turbo] Im a little confused.

[mr2turbo99]

Hi Guys,

as above im a little confused. Ive been doing a lot of research into mods just recently and im getting mixed messages as to what to expect.

I understand over the years a car will naturally lose power, however if its serviced and looked after then that loss is minimal. Now, the Rev 1 and 2 turbos were rated at 225bhp new, which is a pretty nice figure. From what ive been reading it can expect to lose around 20-25bhp over the years.

So my question is....were do the mods fit it? Im going on the assumption a reasonably good condition turbo has circa 200bhp (before mods) due to wear, but if we start adding the mods on (estimated bhp figures according to what ive read) this is how it looks to me. Downpipe - 15bhp, Zorst - 5-10bhp, induction - 5bhp, intercooler 10bhp, raise boost 7bhp for every 1psi. Add that all up based on the top figures and the car should be running around 250bhp. Thing is a lot of people are saying that they doubt it would make those kind of figures and some are saying it would just about make stock BHP. So what am i missing? Am i doing the maths wrong?

Thanks

[notroubleclubber]

i wouldnt worry about working out what u would lose over the years!!!

If you are serios about modding and power then the first port of call is a full service and then a rolling road check to see what power its putting out. This will be your base to start with. Then add the mods that you want and then re road it and see how much extra you get!!

SIMPLE!

[GTS GAV]

Hi Guys,

as above im a little confused. Ive been doing a lot of research into mods just recently and im getting mixed messages as to what to expect.

I understand over the years a car will naturally lose power, however if its serviced and looked after then that loss is minimal. Now, the Rev 1 and 2 turbos were rated at 225bhp new, which is a pretty nice figure. From what ive been reading it can expect to lose around 20-25bhp over the years.

So my question is....were do the mods fit it? Im going on the assumption a reasonably good condition turbo has circa 200bhp (before mods) due to wear, but if we start adding the mods on (estimated bhp figures according to what ive read) this is how it looks to me. Downpipe - 15bhp, Zorst - 5-10bhp, induction - 5bhp, intercooler 10bhp, raise boost 7bhp for every 1psi. Add that all up based on the top figures and the car should be running around 250bhp. Thing is a lot of people are saying that they doubt it would make those kind of figures and some are saying it would just about make stock BHP. So what am i missing? Am i doing the maths wrong?

Thanks

your not doing your maths wrong pal there just vauge on there discriptions, yes maybe Downpipe - 15bhp, Zorst - 5-10bhp, induction - 5bhp, intercooler 10bhp but you will only see these bhp increases an bennerfits if you do other sopporting mods i.e ecu,injectors, turbo and so on, if you get my meaning

[mr2turbo99]

I see. Ive currently got a rev 1 with an Apexi induction kit, Downpipe, Mongoose zorst, XS intercooler, and a Gizzmo MS-IBC controller which im going to set to circa 13psi. Id like to think that my car would put out a resonable amount of power with those mods. What do you think? Im reluctant to believe ive need to spend out just to acheive the 225bhp it was when it was new. Also is that stock power measured at the wheels or the fly?

[Phill P]

My rev2 after 16 years and 97000 miles was running at 205 bhp on the rollers,...however only at .5 bar (should be .7)as the actuator was poop.

Mbc now has it up to .90,don't know the numbers but it should be more .

Not sure what to expect as also has Japseed and Apexi,still running cat though.

High milage doesn't always cause low power.

Paul

[mr2turbo99]

was that 205 before or after the mods?

[Phill P]

Before mods,was totaly standard 97000 mile car,was tested at Surrey rolling road who pointed out that was only boosting to .5 bar and reckoned that it was a weak actuator.So fitted a GTS Chris mbc,and disconnected the vsv.

Have read that a rev 1/2 won't really go beyond 250 unless you go the rev3 route,ie head gasket ct20 ecu etc etc.


paul

[Wingers]

i had a rev 1 with fairly basic mods: intake, exhaust, xs power ic, turbo technics turbo & 1bar boost that was running 265bhp.
That would have been even higher but for a broken tvis butterfly.
I wouldn't be suprised to see 250 with the above mods less the turbo...

Once you're into spending that much money though you probably want to start thinking about getting a rev 3 really. Or investing a bit more and going the whole hog.

Wingers

[dantheman]

hmm, according to my internal combustion engines lecturer permanent power loss from engines due to age is negligible. the majority of power loss comes from carbon deposits. and to be honest having taken apart a 94 ford cosworth engine thats done 150k miles it really isnt worn at all visually. hell after that many miles the crankshaft only had 0.7mm of warp to it. small figures like that wont affect engine performance noticably. so as far as i know the only losses come from poor valve seating, carbon deposits on the valves and chamber walls, and maybe piston ring wear.

someone correct me if im wrong....

[mr2turbo99]

I see. Im not planning any further mods. The general feeling is that its not worth it on rev1 and 2s.....I guess the next thing will be a Rev 3 and start the mod process again.

I have read on a few occasions that some combustion engines actually reach a peak power output after XXXX miles.

[bobhatton]

As an engine frees up with lots of miles on it, it can give more power.....................just before it blows up.
There should not be a loss of power in a used engine.

The only reson to have a Rev 3 is if you are not going to do many mods to it. It starts with more power so any thing done to it will give more than a Rev1/2, but if its going to have most things changed on it, say going for 500hp then a Rev1/2 is better base to start with than a Rev3 because of its weak block.

Bob

[mr2turbo99]

I see. Think ill stick with what ive got for now. Id be very happy to see mine make 240bhp with my mods, probably very surprised too haha

[GTS GAV]

As an engine frees up with lots of miles on it, it can give more power.....................just before it blows up.
There should not be a loss of power in a used engine.

The only reson to have a Rev 3 is if you are not going to do many mods to it. It starts with more power so any thing done to it will give more than a Rev1/2, but if its going to have most things changed on it, say going for 500hp then a Rev1/2 is better base to start with than a Rev3 because of its weak block.

Bob

intresting thread, am i right in saying for a big bhp in the 3S-GTE engine i.e 500-600 it would be better off goin for the rev 5 block as iv read thet the cylender walls are 1mm thicker compaired to the rev3?

also any idea why alot of drag mr2 go for the rev3 block but the rev1/2 head? roy ashby has it on his horishima mr2 in the drag sereis,the engine was built for him directly by hks as he kept blowing the wings of there hks stroker kits and so on, they say that roys engine as queted from HKS is unbreakble, cant see this to be 100percent true but hey ho,they decided on the mating of the rev2 head and rev 3 block any ideas why??

i used a rev3 head on a rev2 block the engine didnt last long and snapped a ringland, i put this down to the water chanels etc didnt match up properly as in there slightly diffrent diameaters,so assumed the ringland failure was due to excess heat an strain on the pistons/cylender walls etc would i be right in sayin that?

[bobhatton]

Ring land problems are from detonation and that could have been caused by lack of water flow in the block but you just match the holes in the block and head with the ones in the gasket and it should all work ok
The main cause of detonation is running too much boost for the compression ratio of the engine and octane of the fuel used.

Rev 1 & 2 heads may flow more air because of the port sizes, will know more about that early next year when I get some on a flow bench.

Bob

[GTS GAV]

i thought that might be the case with the rev2 heads any idea why the port might be bigger compaired to the rev3, do you think this due to the diffrence in turbo setup in the revisions?

[bobhatton]

The Rev 1&2 have 8 inlet runners, 4 open at low speed then the others open up at 4500 rpm I believe. This means the ports are bigger in the head to take the 2 runners per cylinder.

Bob