Technical Newbie needing guidance...

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Technical Newbie needing guidance...

Renrut

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New to forum here as I've bought a Sei Sporting for trackday fun. I'm trying to work out the best way to get some more horsies out of it for the minimum outlay of £££, a fairly common target. A quick shifty on some online 1/4 mile calcs (yes I know they're finger in the wind) shows that to get to the straight line speed of my last car I'll need around 100bhp.

That means I need to find 45bhp from somewhere :eek:

So looking at it simply I have 3 options to round up those extra horsies:

1) Turbo it. Fag packet gives about a 2.2 pressure ratio (1.2 Bar) at 5500 rpm, thats a (relatively) big turbo and lag will probably be fearsome and I imagine something may give on stock pistons/rods/crank.
2) Rev it. Move the power band up to about 10K rpm. I've seen mention of making the 1108 rev this high and that really sounds appealling, but how much work and is it realistic to do on a budget? Is the crank going to want to go its own way?
3) Do a bit of both. Rev it to say 7500 and turbo it with a PR of about 1.5 (so 0.5 Bar). Obviously sounds like the best solution but it'll also need the most time spent and need the most parts messing with which means more potential for something to go wrong.

I'll be doing as much work as possible myself to save money although I'm a reasonably technical person but I know somethings will be beyond me.

So your thoughts please chaps.
 
Which car has the 1242 16v engine that gives 100hp, isn't it more like 85 or something? (I suck at cars other than the sei ;) ) Or do you mean take that engine and tune it further, N/A?
 
How cheap is cheap?

My 1.4 thread in my sig may be of some use.

Or even 1242 16v it for 100bhp.

Turbo would also do the trick with a 1.2 8v low boost, not sur eon costs for that though.

//edit -- checked the stickies and FAQ's?


Kristian

I'm ambitious = Cheap is £500 for all parts and with me doing all the labour. Can stretch a little but maybe only to £600...
Yes I know its ambitious but I figured if I shop around for bits and use a bit of nouse I'll get there. I was thinking an engine swap might just be possible for that but then how much is a 1.2 16V with everything you need to get it running? Seen on the bay of fleas that 1.2 16Vs go for about £200-300 but thats the bare engine no ancillaries or wiring or ecus. And that'll still be short of my 100bhp target. :(

Hence my thinking of dirty cheap turbo or higher revving being the answers.

In terms of project costs I have spare injectors, fuel rail, throttle (probably way too big), wiring, oil pipes etc lying around already so it's mostly the main items. Turbo route -
2nd hand Turbo: £100?
Thinking maybe Megasquirt: £250
Or get single extra injector driver and injector: £50?
Various piping and exhaust: £100
Decompression plate: £10-20 (if I draw it up myself in CAD it'll be cheap to get laser cut)
Need bigger 2nd hand fuel pump : £20
2nd hand IC: £50?

Or if going the revvy route -
Megasquirt (maybe, maybe not): £250
Fuel pump: £20
Road/Rally Cams: £100? Not sure on this bit
Vernier Pulleys: £100?
intake & exhaust piping: £150

So revvy route looks out of it if I need to go to standalone management. Turbo looks just about feasible.

Would anything more powerful than the 1242 fit and still be under budget? If I go the swap route I'd rather pick an engine that will give me the target power straight out the box so budget goes on the swap not messing with it afterwards.
 
Take the insides out of it, for a start. Don't want to be dragging too much stuff about.

Cams are a lot more than £100, so well outside your budget.

I think you will need to find more than 46 BHP.

They only gave 54 when new, it will have lost a few by now.

Bigger engine route is the most cost effective.

Cheers

SPD
 
Fair enough. I havent really looked into costs for replacing the cams, it was a number plucked from some shop on the net and obviously I'll need to change more than just the cam. But revvy idea although would be cool, isnt gonna happen in budget so I need to forget it. (n)

Interior was gonna come out anyway but then I do like my pies :yum: so not expecting to gain more than 50kg there.

Thinking about engine swaps and hoping to borrow some wisdom from you guys :worship:
what are my 'drop-in' options? And what will fit with a little bit of cutting? Obviously still within the £5-600 budget.






PS Yes I know there is no such thing as 'just dropping it in' :rolleyes:
 
Thinking about engine swaps and hoping to borrow some wisdom from you guys :worship:
what are my 'drop-in' options? And what will fit with a little bit of cutting? Obviously still within the £5-600 budget.






PS Yes I know there is no such thing as 'just dropping it in' :rolleyes:

Click on Kritip's sigs, there are several stories there. I went the revvy route.

Cheers

SPD
 
Got mid 70's out of my 1108 with a mild selection of parts. You're missing the larger TB in your plans. Searching for my dyno thread from a few months ago will pull up my spec.
 
Yeah but I do have a spare throttle sat in my garage. Might be a bit big tho as its from a Toyota 1.6. I'll get it out and measure it.

Just read your spec sheet for that RR run. What does the "McKricth (sp?) Chip" do? I assume its some sort of fixed remap but what is the target engine setup? And how much do they cost?

I think unless I can get the power I want from a straight engine swap with no messing I'd rather go turbo route.

For engine swaps as far as I can tell that means either a 1.6 or a very new 1.4 to get 100+ horsies in factory trim. Can't imagine I'll get a new 1.4 for £500 inc ecu etc and not sure a 1.6 will fit. So unless I go with a bike engine it's gonna be another tubby project which seem to be well documented on here (y)

Speaking of bike engined Cinq/Seis are there many around? I spotted one on ebay a few months back but it looked a bit suspect so I avoided it.


ETA - looked up the Mckritch Chip, its the Micheal Crich rechipped ECU. So I'm guessing thats an EEPROM with a new fuel/ignition map. So maybe its possible to remap the car without needing a standalong ECU...
 
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Go down your local breakers and see if you can find any 1.4 stilos that are on the heap. They should be able to tell you if it runs. and if it doesn't why not. avaid any with front end damge but rear end damage will be ok for engines and ancillaries.

Think if you strip it inside and maybe lower it 30mm, then go for simple engine tuning you might get a few more hp. you could be looking a lot of time/work trying to find big power.
 
For engine swaps as far as I can tell that means either a 1.6 or a very new 1.4 to get 100+ horsies in factory trim. Can't imagine I'll get a new 1.4 for £500 inc ecu etc and not sure a 1.6 will fit. So unless I go with a bike engine it's gonna be another tubby project which seem to be well documented on here (y)

i paid £275 for my 1.4 16v stilo engine, it came with ecu etc - but i had no plans on using it (no body computer, and it has fly by wire throttle - which i binned)
 
Didnt realise they were that cheap. I'll look into it then although that means finding an aftermarket ecu as mine is the SPI so no way is it gonna work right on an MPI engine.
 
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