Budget Tu Turbo

[decoc182 0]

First things first, welcome back summer weather, dont know what its like ur end, but up here in "sunny" wales its perfect weather for working on french cars

 

Ive been gathering bits over the last few months for a budget TU turbo. This is what I have so far

 

1.4 SPI Block (TU3J)

XSI/GTI Head (TU3F big port)

MHI TD04-11g-4 Turbo (off a bmw 525d)

Intercooler from an escort

BE4R gearbox off a picasso

180MM flywheel machined to fit 200mm saxo clutch

R5 gtt solex carb

 

Ive hit a brick wall at the minute. I have heard that when fitting the big port head to the small port block, CR should be lowered. Im not sure how much, and Im not sure how to calculate this???. Im going for this method as I dont want to fork out for low comp stuff, and this project is merely a fun time to see me through summer and a VTS engine

 

Does anyone know how much boost this setup would take before going KABOOOM?

 

Im stuck with fuelling. I can either use the MPI system with the head with ecu, or go backwards, and use the R5 GTT carb and bodge up to an inlet manifold, and bulid something similar to the R5 GTT.

 

Any help would be much appreciated. I know some people have done this before, but I just cant find the details.

[axnutty 10]

Go for a carb head, base model inlet manifold and R5GTT carb. As they all nearly match up with just a bit of fettlingand will be much cheaper than EFi.

 

Dont expect big boost.

 

Google CR calculations theres loads out there.

[johnnyboy666 195 1 Cars]

can you take loads of pictures of the fitting of the gearbox please im curious to see how easy it is

[Sandy 189]

I mapped something similar a few months back. A chap called Lex of Saxo Sports Club. He did a great job and it worked really well. Might be worth contacting him.

[Ajr 0]

Lex' seemed to go very well for a budget conversion!

[decoc182 0]

Ill stick with the MPI head for now and see what CR I have. I would much prefer this method than double H/G etc.

 

Nothing is mounted yet, I have a 1.6 GTI subframe with front suspension etc, 1.6 GTI hubs and driveshafts. Have to move gearpost over and drill holes to mount picasso bearing housing/engine mount. We think we will either use 205 gti gear linkage system or use a 306 bodged system.

 

Many thanks for reccomending Lex's thread. I have to say that looks awesome, good work!!!

 

Still toying with carb however, as said is much cheaper to get setup. I have toyed with using the AX GTI managment to control spark only, and use a reprogrammable eeprom insert or use ODB port mapping (IF POSSIBLE???) to change ignition content

 

Or use dizzy and coil etc from AX /205 TU3S and run old fashioned but sturdy

Edited April 2, 2009 by decoc182

[GeorgeXS 32]

I mapped something similar a few months back. A chap called Lex of Saxo Sports Club. He did a great job and it worked really well. Might be worth contacting him.

 

What kind of power was that putting out?

[brolly 0]

ANY update ?

[omega 82]

not 100 per cent but thought you couldnt use a diesel turbo on a petrol engine

[Lan 24 1 Cars]

not 100 per cent but thought you couldnt use a diesel turbo on a petrol engine

 

there the same thing

[wracing 19]

no they are not, diesel turbo are alot different temps pressures pressure seals in different places.

 

ive been there and all you end up with it blow oil seals......pointless

 

 

james

[Lan 24 1 Cars]

fair dues, ive seen t25s on both didnt realise the difference

Edited July 12, 2009 by Lan

[wracing 19]

the egt of a diesel is a lot lower that petrol the 't25' refers to the frame size, you will find that the a/r ratio on the exaust side is far to restrictive for a petrol.

[Lan 24 1 Cars]

o right, thanks for explaning it

[brolly 0]

any photos of this setup ?

[drmo 5]

My colegues 1.4 8v turbo saxo:

TU3J bottom

TU5JP head

lowered CR to something like 7-8:1

big boost 2.85Bar (cca. 41 psi)

biiiig turbo (I think it is T3 or something mixed up)

315hp on the fly

and really long gearbox (FD 3,44 or something simillar))

http://www.avtomobilizem.com/forum/download.php?id=25468

 

Going for even bigger turbo....

[mr_exe 1]

Any updates on this one? I quite fancy turboing our CJ for a laugh,

[decoc182 0]

TBH I havent gone down the TU route anymore, gone for an xu7jp4.

 

I was wondering, I have the iron block engine / Turbo and IC which will run low CR with big port multipoint head. If anyones got some bits spare, whos up for building a silly powered tu3 turbo and then trying to blow it up??

[Sandy 189]

Lex's was running pretty high CR and about 10 psi IIRC. It was about 170-180bhp, which we were pleased with, but gave 40mpg average too, which was nice. He did hit problems eventually.

[Tom Fenton 1,526]

Out of interest, running a homebrew turbo, what problems did he encounter?

 

Mine is fast approaching 4000miles now, and all "seems" well.

[Sandy 189]

I think he thought it melted a piston, but it didn't, I can't remember exactly I'm afraid. It would have been even better with boost control, remiss of us not to have used it. Every build gets better!

[Tom Fenton 1,526]

No probs, cheers. It is a shame you are so far away, as I'm pondering getting mine re-mapped by someone who knows what they are doing (e.g. not by me) and see if there is more power to be had.

[Sandy 189]

Quite a long way, yes! It would be nice to meet you and see your handy work.