[Mk2] [Turbo] engine mods, engine swap, more power etc etc.....

[Ryan S]

Ok, so I'm about to free up quite a bit of cash through my business come March maybe February, I'm not 100% yet, I do know I want to spend it on the car though, I'm happy with the bodywork but I'd like to get a bit more power from the car, so, do I go for a 5sgte build? or use the 3sgte? I actually did think about a v6 turbo but i think it's just a bit more than i'm willing to spend on the car, I'd like to get the car to run a reliable 400bhp which isn't a massive figure but it's what I'm after, is the 3sgte ok at this level of power? what;s the best way to go about it all?? buy all the parts etc then have them fitted, or do it a bit at a time etc? I'll 100% be getting somebody else to build it from start to finish (i'll even put a "bought not built" sticker on it incase I enter any events). what i don't want is my car being off the road for months at a time, ideally maybe build up another engine outside of the car then have it fitted....or do i just bang some forgies (yes Bob, they will be the correct CR) in my current engine with better turbo, ecu and fuelling???


all advice welcome, i've never done a build or anything before and i'm not even convinced i need to do it in all honesty, but, i will have the spare cash and i would like to get something engine wise. frustratingly i;ve obviously just missed out on Gullzters ready built engine

Just to add to this, I'd be very interested in something ready built that could drop right in

[synXero]

Definitely best way is going to be buying everything you want and having it all prepared before you start swapping anything. Prep in the kitchen and that!

I suppose the other thing you need to do is define a budget which will dictate how expensive a setup you can justify ?

[2mad]

V6 tubby .. gets my vote .. why not push the boundaries.

[Ryan S]

V6 tubby .. gets my vote .. why not push the boundaries.

V6 is deffo out, that would require the car being off the road for too long for fabrication etc, plus turboing it would require too much messing about. if there was a v6 turbo option that dropped right in I would do it, but there isn't one that I'm aware of


Yeah I think I'm gonna have to do a bit of shopping, no idea if I should go 5s or just use my current engine still, budget is around the 5k mark at the moment (for parts) then I'll just pay the labour as i go, so probably around 8k, I will have more (quite a lot more) cash but I'm not sure how much I'm prepared to throw at the car, I think a reliable 400bhp can be achieved well within that budget

[Ryan S]

V6 tubby .. gets my vote .. why not push the boundaries.

V6 is deffo out, that would require the car being off the road for too long for fabrication etc, plus turboing it would require too much messing about. if there was a v6 turbo option that dropped right in I would do it, but there isn't one that I'm aware of


Yeah I think I'm gonna have to do a bit of shopping, no idea if I should go 5s or just use my current engine still, budget is around the 5k mark at the moment (for parts) then I'll just pay the labour as i go, so probably around 8k, I will have more (quite a lot more) cash but I'm not sure how much I'm prepared to throw at the car, I think a reliable 400bhp can be achieved well within that budget

i also want it to be useable power not just a top end figure, i.e. 400bhp between 6-7k rpm is a waste of time, i want as much power as possible all the way through the rev range.

[jimGTS]

why is it a waste of time??

engines are designed to make peak hp near redline.

get something that spools quick, makes and holds 400hp at 6-7k rpm

at 400hp, it is not going to spool like a ct20b. you are also not going to be making 400hp at 5k rpm.
you will have a massive 150hp hit from like 4k-5.5k rpm on a 400hp level build so there will be a huge amount of torque difference coming on boost when making numbers like that.

[bobhatton]

V6 tubby .. gets my vote .. why not push the boundaries.

V6 is deffo out, that would require the car being off the road for too long for fabrication etc, plus turboing it would require too much messing about. if there was a v6 turbo option that dropped right in I would do it, but there isn't one that I'm aware of


Yeah I think I'm gonna have to do a bit of shopping, no idea if I should go 5s or just use my current engine still, budget is around the 5k mark at the moment (for parts) then I'll just pay the labour as i go, so probably around 8k, I will have more (quite a lot more) cash but I'm not sure how much I'm prepared to throw at the car, I think a reliable 400bhp can be achieved well within that budget

i also want it to be useable power not just a top end figure, i.e. 400bhp between 6-7k rpm is a waste of time, i want as much power as possible all the way through the rev range.

The first thing you need to do is come up with your engine design, the fuel you will use, the power you want and at what rpm are a good start.
The 5S will be the best way to go as being a bigger volume it will give better low down power.
Do not buy anything till you know your full design.

[Ryan S]

why is it a waste of time??

engines are designed to make peak hp near redline.

get something that spools quick, makes and holds 400hp at 6-7k rpm

at 400hp, it is not going to spool like a ct20b. you are also not going to be making 400hp at 5k rpm.
you will have a massive 150hp hit from like 4k-5.5k rpm on a 400hp level build so there will be a huge amount of torque difference coming on boost when making numbers like that.

I just want the car to behave as it does now but with (say the car is 300bhp) that extra 25% (or 33%) power across the rev range, I don't want a big turbo producing all it's boost between say 6-7k rpm. I want all the boost at once, Power was maybe the wrong term to use.

[Ryan S]

that's the plan Bob, obviously i'll come straight to you with any advice I need on compression ratios, are the 5s blocks easy enough to get a hold of?? what needs done to the block before I can use it?? I can source one and get the machine work done at my end.

[Martin F]

I have a rev 3 turbo block here, would do it for a good price and you could get it built at your own leisure.
Good figure 400 bhp , I loved it, and depending on your turbo there is no reason you couldn't run it at 400 bhp but have it mapped to 480 bhp for those special occasions, with the right Garrett turbo of course

[jimGTS]

I just want the car to behave as it does now but with (say the car is 300bhp) that extra 25% (or 33%) power across the rev range, I don't want a big turbo producing all it's boost between say 6-7k rpm. I want all the boost at once, Power was maybe the wrong term to use.

first off, a turbo of that size isnt going to produce all its boost at that rpm!

it will still make decent boost at lower rpm, say 500rpm-1000rpm+ past a ct20bs. depending on the size/spec.
so say full boost at 3.5-4k rpm in like 3rd/4th gear. as opposed to 3k rpm.

the car will feel laggier than your setup if you want a turbo that will comfortably make 400hp, ie you will probably need to look at turbos capable of 450+.

this lag and power will mean a sharper boost/torque curve and will feel more laggy.

it will make less torque at lower rpm until the turbo is up to full boost.
it will not drive the same.


for example, my old rev2 at 300hp, and my old rev5 at 400hp.
granted, the turbo i was using was a bit old school, but still a very decent turbo.

[Ryan S]

hmmmm, I see what you're saying, I understand for a higher bhp figure sacrifices have to be made in other areas, I think i'm gonna have to do a heap of research on this before I do anything.

Thanks for the offer Martin but if I was using a 3s I think i'd just use my current engine, Gonna start trying to hunt down a 5s block. No respone from slipping clutch regarding his TD06 either (this is unrelated to this build) so i may get back to you regarding the TD05

EDIT: Just a quick question, which head is used with a 5sgte build?? the mr2 or the camry?? there's a camry head on ebay just now.

[Nic]

I personally wouldn't get too hung on peak power figures, if I was building a fast road MR2 I'd choose a moderately sized modern DBB turbo that gives a good broad torque band. Something like a Garrett GT28RS or GTX28RS should spool quicker than the stock turbo but be good for 350+hp with all the supporting mods. For me it'd be a much nicer everyday car to drive than a big hp MR2 with a narrower useable power band higher up the rev range.

[Ryan S]

I personally wouldn't get too hung on peak power figures, if I was building a fast road MR2 I'd choose a moderately sized modern DBB turbo that gives a good broad torque band. Something like a Garrett GT28RS or GTX28RS should spool quicker than the stock turbo but be good for 350+hp with all the supporting mods. For me it'd be a much nicer everyday car to drive than a big hp MR2 with a narrower useable power band higher up the rev range.

this is what i'm after to be honest, the car will be a daily driver so something fast spooling is what I want, I'm not hung up on 400bhp, I want the car to be as driveable a possible, Actually, i've already said what i want, basically the way it drivvves now but with a bit more grunt. Talking about it now i reckon i could probably get away with throwing in a set of forgies, decent fuelling and a decent ECU.

also, there's a camry on ebay for £800 too.

[bobhatton]

that's the plan Bob, obviously i'll come straight to you with any advice I need on compression ratios, are the 5s blocks easy enough to get a hold of?? what needs done to the block before I can use it?? I can source one and get the machine work done at my end.

No they are not easy to find over here.

No work needs to be done to the block apart from fitting oil squirters
You will need custom 5s/3s pistons and I would also get the correct rods to fit the 5S crank, not turn it down to fit 3S rods

[Nic]

A Garrett GT/GTX28RS would be perfect for what you want then IMO, it'll spool quicker and pull harder with a good broad useable power band.

[bobhatton]

EDIT: Just a quick question, which head is used with a 5sgte build?? the mr2 or the camry?? there's a camry head on ebay just now.

You only use the block and crank from the 5S

[jimGTS]

yep something that size would give the ct20b a kick.


personally, i would get something that size, run it on the car for 6-12months, with the right mods/tuning, a gen3 should handle that fine.

then once your bored of 350hp, get something bigger, then go down the forged route and shoot for 450+.

[bobhatton]

yep something that size would give the ct20b a kick.


personally, i would get something that size, run it on the car for 6-12months, with the right mods/tuning, a gen3 should handle that fine.

then once your bored of 350hp, get something bigger, then go down the forged route and shoot for 450+.

This will do the job

http://www.turbobygarrett.com/turbobyga ... r#GTX2867R

[Shmed]

I have a 5S block and just de-tuned from a GT35 to a GTX3071 and I couldn't be happier.

You can't tell from the pics in the link, but full boost is around 4700RPM with it building from around 3800rpm.

http://www.imoc.co.uk/forums/viewtopic. ... c&start=60

Still makes close to 500HP and is an animal to drive...