Need More Power

[DVST8R]

Well as I stated previously no camera so unfortunatly no pics. The motor that vw racer has in his link is a 1.9TD but is very close to the same it just has another sensor? attachment on the top of the pump, but my mod list will work for either.

[1985JettaTD]

ok, thank you for all the help, you really know what ur talking about!! one more question thought: on the first post you said that a bad intercooler job would mess everything up. what i want to know is what a bad intercooler would mean. is it the intercooler itself or in install job or both? and what can be done to stop that from happening? thank you  sooooo much!!!!!!!!!!!

[DVST8R]

Sorry let me clarify, a crappy intercooler is what I was refering too.  The charge pipeping if exsesive in size or length can hurt spool up time (ask me how I know  :roll:  but thats about it, however a bad intercooler is worse then none at all. A poor intercooler is one with a large pressure drop, poor effciancy (sp??), and poor flow. If the intercooler your concidering has anyone of those traits move on.

As for sounding like I know what I am talking about a big thanks to all of the contributers to our former forum that is where I learned 90% of what I know about vwtd's and probably 80% of what I know about diesels in general.

[AntonUK]

hi im quite new here, anyway this is an awesome post! far more detailed thank that link.

im just wondering is it possible to put a TDI head on the TD engines?? Iv read somewhere that they are more efficient in terms of temperature of combustion? if it is possible (i maybe sounding dumb without relising), is there any power gains from such a conversion?? Iv just been thinking why the TDi's are 90bhp whereas my TD is 75bhp (93 jetta).

also, how much do the injectors of the TDi compare to the TD. Im looking at injector upgrades as mine are packing in!

cheers for any info!

[fspGTD]

The charge pipeping if exsesive in size or length can hurt spool up time (ask me how I know  :roll:  )

OK: How do you know?    Let's hear it, thanks.

[deepmud]

hi im quite new here, anyway this is an awesome post! far more detailed thank that link.

im just wondering is it possible to put a TDI head on the TD engines?? Iv read somewhere that they are more efficient in terms of temperature of combustion? if it is possible (i maybe sounding dumb without relising), is there any power gains from such a conversion?? Iv just been thinking why the TDi's are 90bhp whereas my TD is 75bhp (93 jetta).

also, how much do the injectors of the TDi compare to the TD. Im looking at injector upgrades as mine are packing in!

cheers for any info!

I am going to say "no". The 1.9IDI uses a pre-combustion chamber, a small "bulb" cast in the head, to inject the fuel and start combustion in - along with this it has flat pistons that come right up to the head. The DI has a combustion chamber cast into the top of the piston, and "directly" injects the fuel into that.
There are DI's with the IDI pumps(EDIT - TDI engines that enthusiasts have fitted with IDI pumps) - the difference being that the IDI pumps are full mechanical (or nearly so) while the TDI is controlled by the computer (other diffences as well, but that's the basics).
So no, can't put a DI head on an IDI motor/block, to my knowledge.

EDIT: my personal knowledge of TDI motors comes from working on FORD 7.3 Powerstroke V-8s(TOTALLY different injection system) but the piston with/chamber cast into it should be similiar - others may know more.

[DVST8R]

Well since you asked, I have gone though 3 versions of my current intercooler charge pipe setup. Version 1. 2" pool hose with 90 elbows routed about the longest way that you can imagine (from beside the alt. under the car across where the front bumper is up by the powersteering res. back towards the fire wall and then finally to the intake) net slightly better egt's then stock and max boost in third gear up 'test hill' (note same hill as I always use using same procedure as I always use to test my new mods) net result max boost of 23 psi @ approx 3900rpm. Next version same as above but using mandreal bent exhuast tubing welded with two silcone conectors for system flex. Net result max boost 23psi @ approx 3600rpm with about the same egt's (in safe area so didn't pay much attention) Third sytem back to pool hose with crappy 90 elbows but, now about a foot longer hot side and about 6 feet shorter cold side. Net result max boost of 23 psi @ approx 3200 rpm. Fourth version in progress about a foot shorter then 3rd with 2" mandrel bent exhuast tubing. In the mean time version no intercooler back to stock rubber elbow. Net result max boost of 24 psi @ 2900 rpm (and the car feels way quicker through out the rev range) egt's still in the safe area. Now considering leaving it like this till either I get my pump tweaked for alot more fuel, or till I can afford a sperco intercooler.

As for AntonUk, deepmud is correct you cannot swap the head.

As for deepmud the pumps they are swaping are still DI pumps but are fully mechanical, idi pumps do not create the pressure needed to opperate the DI injectors.

[Spike_TDI]

You can't use an IDI pump on a DI. The IDI pump won't make enough pressure to make the DI run/run smoothly.

There are people that have built mech. pumps for DI's. There are a small number of DI's that run a mech. pump and a even smaller number that are available it NA. I built a mech. pump for my TDI using parts from a Land Rover 300TDI, and a VW TDI.

[1985JettaTD]

The real test of an IC's effectiveness is to measure the air temperatures pre-and post-intercooler. If the IC is lowereing the charge air temp, you should be able to increase fueling, resulting in more power and faster boost build. If your car isn't smoking like a steam train going up a grade with the IC out of the loop, then you were't fueling to max anyway...

Ok, i do not have an intercooler in my car right at the momment. i am looking for a good one to put in the car. should i be putting in the intercooler first before i do the injector pump mods:

Ok lets start with the max fuel screw as even with out extra boost these motors can still definatly use extra fuel, so for this mod just break off the coller (either remove completly form pump and then remove or find the seam and pry it off with a well pointed flat blade screw driver . . . . . Note the location of the wheel, mark it, and count any turns for reference. Remember: Star wheel down=less spring resistance=increased fuel delivery rate.

or should i wait till the mods are done before the intercooler goes in? right now i have only played around with the max fuel screew on the front of the pump and it smokes like a semi truck when ever it is put under load. is that enough for the intercooler to give power boost or does it need even more fuel?

and about the egt gauge:

What this didn't cover as I had already covered it during this persons build up are the upfront costs. **These things must be in place b4 any thing you start to mod.

1. ***Exhaust from turbo back at lest 2.25" mandrel bent 2.5" is ideal, 3" is doable but takes alot more fabing.

2. Gauges. egt gauge, boost gauge, are the minimum, if you are going to do the govener mod then add a tach to that.

is this something that i really need for mods like this? i was out shopping for them today and the cheapest one i could find was $180cad. why is it important to know the egt anyway?

thanks!!!

[DVST8R]

I'm not sure if you were responding to me or somebody else. If it was to me then I do realize that, and I am not looking for more power from an intercooler but to keep the intake charge as dense as possible (hopefully resaulting in less power lost) but the primary reson is that wiht the denser cooler air charge the cumbustion will be more complete and therefore cooler and lower egt's (not that ths is yet a concern, but I believe that it will become one once the pump has been moded, espetialy if I go with a big single tubo vs twins, as the time before the big turbo is spooled up will be an area of high egt's and a concern)  However as of right now my fuel is turned up as far as the stock pump will alow my idle is approx 1300rpm with the min idle screw right out of the pump. It still will only smoke upto about 18psi or so depending on rpm range.

If this was diercted to someone else then please ignore :wink:

[DVST8R]

In reply to 1985Jetta TD

What are you running for an exhuast??? This should be your first and foremost place to start, I would not advise playing with the pump untill this has been adressed.

2nd, No you don't have to by an EGT gauge, but how else will you be able to tell if it is too hot and about to damage somthing?  (sorry if I am razing ou abit here, but yes it is definatley worth the 180.00 or how ever much you have to spend on it. The EGT or Exhaust Gas Temp. Gage reads jsut that how hot the exhuast temp is. When you over fuel a diesel motor alot of heat is created quickly the only way to "keep it safe" is to know where is it at, the only way to do this is with an egt gauge. P.s the way to overcome too much fuel is to add boost, this is where you see the power gain is form burning the previously exsecive fuel.

If you put an intercooler on now or after isn't is important as an exhaust and proper gauges so if you can only get two of the three the intercooler can wait. As I stated previously right now as I am building / designing my new charge pipe I am running with out an intercooler and my egt's have yet to even enter the yellow. I contribute this to a very free flowing exhuast (3" mandrel bent) and enough boost to burn all of the fuel.

[1985JettaTD]

ok i get it now, thank you.
i think that i am going to take it in for exhuast next week. i am planning on doing 2.5'' from the turbo back with just a muffler. what kind of muffler sould i use? the poeple at the shop said they would put on a performac one, does one like that help the flow compared to a stock one? what do u people sugest?
btw: this is the first time that the exhuast is being changed on my car, that right baby, 500 000 km and it still has no sign of failing. sorry, i just think that it is sooo sweet that it is still factory exhuast, lol.
thanks again!!!!

[DVST8R]

I am running a dynomax bullet it is out of there race series, it is the best flowing muffler that I have come across, and was only like $70.00 form the local parts store. Don't put a flowmaster on they do not flow well, you are looking for te least resistance possible so something wihtout baffles, something straight through so if you look in one side you can se right out the other, and have them put it as far to the rear of the exhuast as is practical.

Thats amazing I have never had an exhuast last more then about 5yrs. :shock:

[fspGTD]

Thanks, DVST8R, that is interesting - now I want to test bypassing my intercooler vs comparing the results with the intercooler installed.

[BlackTieTD]

i'm still stumped about this whole 2.5, 3" exhaust thing...

what are you guys doing for a downpipe? as far as i know, short of fabricating from scratch, the best you can do is modify a mkIII downpipe, which has an inner diameter of about 2.125".

if anything, i'd rather have the most free-flowing part of the system be the downpipe, rather than have it be the bottleneck.

i've realized the $150 mkIII TD downpipe i bought won't work with my car/turbo without doing more work to it than its worth... so i'm all ears for downpipe options... i would like to go as big as 2.5" but anything bigger will surely bang off of the body or shift linkage in a mkI....

shameless plug: the above mentioned downpipe is for sale. mkIII TD downpipe, k03 or k24 flange (dr. diesel can you clarify i can't even remember anymore), including flex pipe and cat/soot-collector. i'll sell it for what i bought it for or at a loss if i have to.