Hi guys,

I'm looking for a VL36/VL37 turbo for my Fiat 704cc 126 BIS (as a potential project)... if anyone knows the turbine housing AR it would also be greatly appreciated. I'm hoping there may be some lying around from upgrades in peoples garages!

Looking for as cheap as possible really, i'm a little worried that the turbine housing AR may be a little large for the application though and perhaps an RHF3 with smaller turbine housing AR would spool up quicker...

How is the spool on the t-jet and what kind of rpm does it hit max boost? What kind of boost can the turbo hold reliably with a remap? I'm looking for about 1.3 bar at a push.

Also is the VL38 physically bigger as it appears to be an RHF5 based turbo?

I'm hoping I can copy this post to the other T-jet sections of the forum in hopes to grab someones attention.

From my brief knowledge on the subject matter reading around on this forum. The VL36/VL37/VL38 all have the same turbine housings. Only difference is the actual turbine. VL37 being the weakest, VL36 being in the middle and the VL38 being the best (Used in Abarth 500). Unfortunately I don't know the AR as it's really difficult to find info on these RHF3 turbos online. The VL38 is however a RHF3 model but I do see Google also lists it as a RHF5. The turbo usually kicks in with max torque and max boost at 3000rpm. But this will change with a remap. I've seen pressure's of 1.2 Bar coming out of the VL36 so there's a good chance it can handle 1.3 bar. Hope this helped and anyone is free to correct me on something I may have said incorrectly

I thought the order was vl37<vl38<vl36 seeing that the vl38 is used in the abarth .. but on the lower power models 135hp and the vl36 is used on the T-jet 150hp.
According to Fiat the max torque for the t-jet 120/vl37 is at 1750rpm
i can't remember for the t-jet 150.

Pressure will depend on the turbo but also on the amount of air that the engine can consume, how much air it can flow, and rpms.. since you want to install it on the smaller 704 cc.. the turbo should be able to provide you with the pressure... but i have no idea at what rpm ( should be around 4k-5k)

Cheers for the replies guys, looks like it should do the job... just wondering why they flow so much air compared to say a daihatsu ihi rhf3 from a copen which has an ar of around 6.

Now I just need to locate one for a good price.

I think the order should be vl37 <vl38 <vl36 perhaps but only because I'm unsure if it's an RHF3 or 5! .

Have since made a classified wanted ad:

https://www.fiatforum.com/classifieds/showproduct.php?product=32634

Yeah if the VL38 is used on the Abarth it would actually make more sense for it to be VL37<VL36<VL38 because the Abarth as a bigger stock HP. Same with the Alfa Romeo MiTo. It also has the VL38 and is ever so slightly more powerful than the Bravo

VL37 RHF3 = Bravo/500/Grande Punto 120BHP
VL38 RHF5? = Arbarth 500 135bhp (may be a direct replacement but whats the overall size comparison like compared to the others I wonder... this would confirm whether or not it is an RHF3 or RHF5.)
VL36 RHF3 (VL37 with larger internals) = Arbarth Grande Punto 155bhp

I'm also wondering what bearings they appear to have in them... from my research it appears not all RHF3 are ball bearing turbos... and these most likely use journal bearings... however I read one place that the VL36 is just a ball bearing version of the VL37. Will we ever know!? Anyone stripped one down and can confirm whether journal or ball bearing? .

I think this is how it goes...

I'd also like to get down to the answers of all these questions as I'm also curious about such. I always remember the VL38 being referred to (here on the forum) as a RHF3 and the first time that I've ever heard it possibly being a RHF5 came from you.

The turbo cartridge seem to be the same between VL36 and VL38 http://turbocharger.gmc.globalmarke...o-vl36-vl38-turbo-cartridge-chra-4925914.html and they refer to it as the RHF3.

However I do think the VL38 has bigger housing, but maybe not big enough to be considered a RHF5.

Hope someone else can shed light on this topic

The vl38 & vl37 have the same size housing but the vl36 is slightly bigger also the better turbo to buy for the bravo as the boost comes in later than the vl38.

So basically vl38 is better for smaller cars that's why it was designed for the a500 as the boost comes in and dies out earlier. Not to say it isn't i decent turbo as I had one in my grande but the vl36 will make more power.

JackFi said:

The vl38 & vl37 have the same size housing but the vl36 is slightly bigger also the better turbo to buy for the bravo as the boost comes in later than the vl38.

So basically vl38 is better for smaller cars that's why it was designed for the a500 as the boost comes in and dies out earlier. Not to say it isn't i decent turbo as I had one in my grande but the vl36 will make more power.

Click to expand...

The VL36 will make more power... BUT only if there is enough exhaust flow/volume to spin it.
Since the OP wants to put it on a ~700 cc engine ( half of the T-jets) .. I'm afraid it will make that power to high in the rev range to be of any use..that is if the engine will be able/like to rev that high, as it's only a 2valve/cylinder (or am i mistaken??) .

If it was me i would go for the VL37(smallest and maybe cheapest and easiest to find as a lot of people with them want to upgrade) ... and i would only upgrade if the boost at top speed drops off to much (not likely as it holds enough boost in the 1.4 T-jet up 4k rpm)

aurick86 said:

The VL36 will make more power... BUT only if there is enough exhaust flow/volume to spin it.
Since the OP wants to put it on a ~700 cc engine ( half of the T-jets) .. I'm afraid it will make that power to high in the rev range to be of any use..that is if the engine will be able/like to rev that high, as it's only a 2valve/cylinder (or am i mistaken??) .

If it was me i would go for the VL36(smallest and maybe cheapest and easiest to find as a lot of people with them want to upgrade) ... and i would only upgrade if the boost at top speed drops off to much (not likely as it holds enough boost in the 1.4 T-jet up 4k rpm)

Click to expand...

You mean the vl37 at the bottom

JackFi said:

You mean the vl37 at the bottom

Click to expand...

Yes I do!.. edited

Hi aurick86, ty four your input... I came to this conclusion myself a couple of days ago and I have a VL37 on the way and also an IHI RHFVQ38 from japan although a VQ50 trim from a copen would of been more desirable along with some others with ball bearing options. I found much interesting information on upgrades for the t-jet... I'd love a T-jet . Yes it has 2 valves per cylinder. I came across Garretts GT1238SZ/Z/lSZ which also looks like quite a suitable candidate. I'd be looking at GT1446's for the t-jet personally for a good turbo .

If anyone has any VL37's lying around from an upgrade or GT1238's i'd be interested still!

I compiled a spreadsheet of all turbo's i've came across so far and managed to find some illusive compressor maps for a couple of turbo's.

I think if I could find some TD015's I could probably even go twin turbo. lol.

http://www.ingas-eu.org/docs/741.doc - worth a look, as is the whole project (final report here: http://www.ingas-eu.org/docs/INGAS_PROJECT_FINAL_REPORT_31May2012.pdf) . The dodge dart forums over in the US also have some useful information around. Along with italian Alfa sites!

I think a VL37 will spool up and provide power in all the areas I want it though so should be a good candidate... I just like the blow off valve in the compressor housing on the Garrett's as it may run a little in surge and that would help a little.

- that ski-doo certainly spools up the GT1238 pretty damn quickly!

The VL37 I bought from ebay.it arrived today however i'm not entirely happy.

It came split in two and is missing the v-clamp so I need a replacement . There is a locating pin between the compressor and exhaust housings that is missing as to get the proper position when i've found a v-clamp.

When the turbo has been split the the actuator has been left attached to the bracket which links to the exhaust housing wastegate via a shaft protruding from the outside. Instead of being removed on the actuator rod via the circlip it has been broken from the exhaust housing side . Can probably be welded up quickly but not happy .

Also missing loads of studs from the downpipe section of the exhaust housing. .