New thread. Two tone s - going boost

[Danny78VTR]

I've been back and forth about what to do with my car as my coilpack, alternator and coil wires split all at once, thought of new cars but can't justify to get rid of my two tone..

Been saving for a while and got some ££££ saved up before I started talking.
Looking for a decent set up aiming 250bhp on a gt25 turbo + be box
As it stand I'm trying to build it for under 3500..

If anyone has links to parts for this then hit me up.
As time comes I won't be needing parts on my car so a few breather mods and exhaust etc will be going in the for sale thread.

So I've started pulling the engine apart to get some stronger rods and arp bolts, new pistons and rings in the engine, keep my cams, inlet the same, more than sure I'm going omex with turbo loom
Should be updating this more often as I'm slowly buying parts

[ThrushMotorsport]

250 reliable for under 3.5k - that's pushing it I'd think for a good spec, 1400 atleast for be conversion fully done, then you need internals + arp rod bolts, big ends, mani, dp, oil feed, water feed, dp and management - unsure if you'll make that, but if you can manage on that budget - hats off

I'd look at a ko4 on the tuj4 - quick spool, and you will go faster than a gt28r as no lag on such a small engine

[Danny78VTR]

Obviously I want it reliable but this will be used probably less than 5000miles in a year so it's not a great deal.. Turbo and mani, downpipe and exhaust I'm going new, then looking around to see what pops up, I think it's achievable,
Not keen on the k04 turbos as I'm liking the dp kit allot more so keeping it as dp mani and garrett turbo

[ThrushMotorsport]

The problem is, on a 1.6 is how long does it take a gt28 to spool


I.e you stick a 200 bhp small turbo vs a 240 bhp bigger turbo (gt28), get them both to start at 50 in 3rd, gt28 will more than likely loose, I'd think gt25 would be a better choice, 28 is probably better for 330+ mark, it's a big turbo and far too a big turbo to make it a quick car for a 1.6 due to the lag

Just my 2 cents really, bigger is not always better in some cases

Dp do a mani for kkk turbos, however I don't think they do a downpipe for them

[Danny78VTR]

I can see where your coming from but obviously once I have more savings, there will be more boost and costs going into it but wanna start with something half decent first, no point going gt25 then maxing it next year when I could have a 28 with reasonable boost and then can push it more, understand where your coming from but I've been on this for months now and think its my best option

[MrChris]

Not telling you its wrong and i see where your coming from but i agree with thrush

Remember ross dagley replacing his big turbo with a smaller one and saying its the best move hes ever made, and the power is much more useable day to day

[Rossp]

330 on a gt28 is at its *absolute* limit - and WAY outside the compressors efficiency island. You're introducing nowt but heat up there. It will also make a bar of boost by 3500rpm and be on full boost (24psi is about their limit) within another 500rpm.

The gt28 is a great turbo for midrange power - upto around 300hp and the "lag" really becomes unnoticeable. You just learn to drive with it.

250bhp ATF reliably is easily done on a budget of £3500 if you can do most of the labour yourself. Biggest expense would be turbo itself, pistons, manifold, and ecu/mapping. Don't be fooled into thinking that you MUST have a DP style tubular manifold though - nice as they are, turbo manifolds are very kind to you: they don't really care that much about "equal length" or even so much on primary sizes etc, not until you're looking to extract maximum power.

For a REAL 250bhp the gt28 isn't a bad choice to be honest, and you'll find the figment (t25 flange) easier to come by on manifolds. But, as said above, the gt25 would give you faster spool over the gt28. BUT (and its a big but) when you want more power (and you will) you'll be changing from the gt25 to the 28 anyway...

The turbo of choice (cost vs performance) if you're buying new would probably be a gtx2863r - spools a fraction faster than a 2860 disco potato, but massively outflows it. Good for around 350bhp and very responsive in the transient area of the plot.

Edit to add: I went from a gt3071r to a gt2860rs and yeah - that was the best move I made lol. The 30 was fucking unusable. Nothing. Nothing. Nothing. Nothing. (There goes a cammed vts...). Nothing. EVERYTHING. WHEELSPIN. CHANGE GEAR. WHEELSPIN. Yeah. Sucked. Lol

[smiith]

These photos are mind blowing!

[Rossp]

Oh forgot to add - if you're staying below 300bhp and 7500rpm then don't bother with rods - save your money.

Ecu wise, predator is cheapest route in for aftermarket.

If you've got aftermarket cams in there already, get shot of them and put the standard vts cams back in - will be better for the boosted setup. The inlet from a 708 or ph3 etc works well but there's too much overlap on the exhaust for boosts preference. Standard is better

[Aly]

Originally Posted by smiith

These photos are mind blowing!

[Danny78VTR]

Originally Posted by Ross

Oh forgot to add - if you're staying below 300bhp and 7500rpm then don't bother with rods - save your money.

Ecu wise, predator is cheapest route in for aftermarket.

If you've got aftermarket cams in there already, get shot of them and put the standard vts cams back in - will be better for the boosted setup. The inlet from a 708 or ph3 etc works well but there's too much overlap on the exhaust for boosts preference. Standard is better

Cheers for the massive help! What I needed, as it stand I wanted to do rods but I may stay std internals until I decide to push more power. I'm the long run I will be better with the 28 hence why choice
Last time I looked I don't think they done a 3plug pred? And I only wanted omex as I could do with a new neater loom aswell
My current cams have just been reprofiled

Again thanks for the help!

[Danny78VTR]

Originally Posted by Aly

Dafuqqqq is that ...

[Aly]

Originally Posted by Danny78VTR

Dafuqqqq is that ...

That's smitths 306

[Danny78VTR]

How my car stood before taking it apart



I got rid off my leather Monaco s buckets and put my old gti leathers back in..

[Rossp]

Double headgasket job will see you clearing 200bhp and would be reliable but ideally you'd have pistons and (as a minimum) arp rod bolts. Don't bother with arp head bolts ever IMO.

Low comp pistons and arp bolts will have you at 250-275bhp all day long on a gt28.

Get standard cams back in then.

[Danny78VTR]

Originally Posted by Ross

Double headgasket job will see you clearing 200bhp and would be reliable but ideally you'd have pistons and (as a minimum) arp rod bolts. Don't bother with arp head bolts ever IMO.

Low comp pistons and arp bolts will have you at 250-275bhp all day long on a gt28.

Get standard cams back in then.

Yeah that's what I want, aim for 250 see what happens, only thing I'm unsure will be injectors if/or fuel pump
And that's two hg at what size?
Il try whip some cams up then! Haha

[Rossp]

Yes you'll need injectors and fuel pump. Standard fuel lines are fine. Walbro 255 ideal pump (in tank, use standard in tank swirl pot)

Head gasket thickness will depend on a few things - how much you skim the head when it comes off, what you want your final CR to be, and who's mapping it ultimately! The higher comp the nicer it'll behave off boost and with good mapping will be fine. Higher CR and poor mapping = det/boom though so you pays your moneys, you takes your choice

[Danny78VTR]

Originally Posted by Ross

Yes you'll need injectors and fuel pump. Standard fuel lines are fine. Walbro 255 ideal pump (in tank, use standard in tank swirl pot)

Head gasket thickness will depend on a few things - how much you skim the head when it comes off, what you want your final CR to be, and who's mapping it ultimately! The higher comp the nicer it'll behave off boost and with good mapping will be fine. Higher CR and poor mapping = det/boom though so you pays your moneys, you takes your choice

What engines run suitable injectors I could source? Heard 491cc injectors would be ideal...
What's cr ? Sound like an amateur now! Also I'd say atspeed are known for there work so would say them unless there's nicer mappers out there, don't mind traveling.
Say the heads all good double up on a 0.7mm hg?
I have read allot and seen builds done at 2500-3000 decent ones so I allowed a little more for now

[saxokid100]

Sounds interesting project...

[Rossp]

Iwp069's are a good bet. 490cc or more at higher pressure, fit in standard rail.
Beware of cheap Chinese copies sold at too good to be true prices.
Good injectors those.