I am pondering on building a turbo kit for my H22 Crx...but not up front thinking of out back... like the newer corvette turbo kits... ... Thank you... advice/comments?

Since it's mounted out back here are my questions... my goal is only 5-6 psi and about 50 more hp then what I got... T3/T4 turbo

Mounting the turbo out back what kind of electric oil pumps would I need and what is available? 1 or 2 in and out?

What size of oil lines would I need?

I don't think an intercooler is necessary for my psi goal...plus being out back would get cool as the IC pipe ran forward?

Where should I mount the BOV... up front near the TB?

Where should I mount the WG... up front off the header or near the turbo out back?

As far as turbo lag? I don't thing there would be too much considering front mounted turbo and all of it's IC plumbing may be close to the same length?




Modified by ESP.net at 10:05 AM 12/5/2007

 

i been wanting to do that for a few years now

it's gonna be loud i had seen it on a twin turbo f250 and it's loud as hell

 

drawing i did...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ESP.net &raquo;</TD></TR><TR><TD CLASS="quote">drawing i did...

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for the oil line i was thinking about making a oil tank with a pump for the feed line and the return line back to the tank maybe with a oil cooler on the feed

but like how you want to do it and you don't need a intercooler that way with it in the back

 

well. . i really cant tell what ur trying to say on that drawing, maybe its just me you might want to make new one.

but as for turbo lag, its not because of the IC piping, its because the exhaust gasses cool as they travel farther back, and the cooler the exhaust is the worse they are at propelling the turbo and spinning it faster, it takes longer for the turbo to spool because it takes longer for teh hotness to reach it.

 

as far as the turbo lag is concerned, I would assume that there would be more then usual since there is more piping to pressurize. I would also tend to think that regardless of the distance the pressure has to travel, from the back to the front, that it would still maintain an elevated temperature and you could benefit from an intercooler of sorts.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by teg racer 877 &raquo;</TD></TR><TR><TD CLASS="quote">well. . i really cant tell what ur trying to say on that drawing, maybe its just me you might want to make new one.

but as for turbo lag, its not because of the IC piping, its because the exhaust gasses cool as they travel farther back, and the cooler the exhaust is the worse they are at propelling the turbo and spinning it faster, it takes longer for the turbo to spool because it takes longer for teh hotness to reach it.</TD></TR></TABLE>

Makes sense... thanks... then I'd probably be better off choosing a turbo with a lil more power earlier in the RPM range then normal... id like to see full boost around 3k RPM anyone with any turbo spec ideas? and as always a turbo that will do the job on a budget

 

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mattssi &raquo;</TD></TR><TR><TD CLASS="quote">as far as the turbo lag is concerned, I would assume that there would be more then usual since there is more piping to pressurize. I would also tend to think that regardless of the distance the pressure has to travel, from the back to the front, that it would still maintain an elevated temperature and you could benefit from an intercooler of sorts. </TD></TR></TABLE>

agree'd never hurts to add a intercooler cools down temps translates to more power

However my boost goal is like 5-6 psi (stock internals) looking for 50 hp or more with that psi range... the thinking I thought was 5 psi or lower IC isn't a must and it being out back much cooler id think that it would be fine without one

200 whp now so 250 id be happy with somewhere around 200+ ft lbs of torque...

 

something like a gt25 or a t3/t4

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ESP.net &raquo;</TD></TR><TR><TD CLASS="quote">

Makes sense... thanks... then I'd probably be better off choosing a turbo with a lil more power earlier in the RPM range then normal... id like to see full boost around 3k RPM anyone with any turbo spec ideas?</TD></TR></TABLE>

so its an h22, but your only looking for about 250whp.... I think a small t3 t4 would work well.

like 48 ar, 50 trim maybe.

 

Yes JDM H22, SS valves...thats pretty much it...

anything more then 250 whp would be great for 5-6 psi we just dont want a turbo to spool up way late... 3-4k rpm is the goal i think for full boost


Mounting the turbo out back what kind of electric oil pumps would I need and what is available? 1 or 2 in and out?

What size of oil lines would I need? same size and specs as a typical front mounted turbo? or larger since, longer distance?



Modified by ESP.net at 10:57 AM 12/5/2007

 

I have some questions too. Why not do a normal setup and add 100hp instead, due to the larger a/r for the same spool? Building a turbo setup for only 50hp..? People who run remote mounted setups mostly do it for clearance/packaging reasons.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by rorik &raquo;</TD></TR><TR><TD CLASS="quote">I have some questions too. Why not do a normal setup and add 100hp instead, due to the larger a/r for the same spool? Building a turbo setup for only 50hp..? People who run remote mounted setups mostly do it for clearance/packaging reasons.</TD></TR></TABLE>

Good questions... I am pretty **** on how the engine bay would look, yes I could cram a turbo kit in the front (H22 Crx) but i'd rather keep it clean up front and run it out back... I think it would be lil different too not to mention still look NA up front... we can have all the fab. work done in house to make the kit and have it look clean, but I just need some insight on parts and how to go about it...

As far as only 50 whp increase on 5-6 psi that is just me being realistic anything more then that would be great with 3-4K RPM spool up...

I don't think mounting it in the back will loose that much more power as long as the turbo specs are right...

 

I am also curious if an aftermarket oil cooler would work for the turbo? Then I wouldn't have to tap into the engine?

If I did tap into the engine and I used an electrical oil pump would there be an issue of starving the engine?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by teg racer 877 &raquo;</TD></TR><TR><TD CLASS="quote">its because the exhaust gasses cool as they travel farther back, and the cooler the exhaust is the worse they are at propelling the turbo and spinning it faster, it takes longer for the turbo to spool because it takes longer for teh hotness to reach it.</TD></TR></TABLE>

Wow, why do people always think that? The VAST MAJORITY of the energy comes from the <U>kinetic energy</U> across the turbine, aka moving gasses through the turbine. If it was the heat and not the overall kinetic energy (mass * velocity), we'd get boost at idle.

They've proven that rear-mounted setups work, and work great. You run a much less restrictive exhaust post-turbo (all of 24" of 3-4" pipe), get to run a manifold thats great for scavenging, and can easily make it dual 2" exhaust if you're concerned about splitting the pulses.

As for what should work, 2-2.5" charge piping, a normal sized intercooler, a 50-57trim t3/t04e, dual &lt;2" or single 2.5" exhaust to turbo, and 38mm WG. BOV can be put anywhere really, but best if close to the turbo. The intercooler will still help, as there won't be enough surface area on the charge pipes to cool down ALL of the intake air. As for the oil, you could run its own oil sysytem w/pump & cooler, or you could feed it with a long tube/hose from the engine, use a normal $70 scavenging pump, and run it back.


BTW someone did a rear-mount turbo CRX recently, and IIRC you wouldn't be able to tell it was rear-mount if you looked at the numbers (spool and whp). They basicly removed the spare tire area and used that space for the turbo/WG/BOV.

BTW2 you will want to make sure you use good gaskets or v-bands on your exhaust, a leak will be a big problem, a little bit moreso than a normal setup.

 

Hmm I wonder how big the cooler would need to be...to be efficient for the turbo...

 

You don't need a pump on the oil feed, just on the return. STS also uses a hobbs switch connected to the pump that alerts you if you lose pressure.

Also, since you are pumping the oil return, you can drain it onto the top of your engine if you like. STS plumbs the oil back through the oil fill cap.

Hobbs switch and oil return pump:



Oil return to the oil cap!

 

I actually have plans to introduce a rear mounted turbo setup for the 4.0L jeeps! The results that I have seen have been very promising.

The kits that I will be making are a peice of cake to build/install and should be just as reliable as a normal turbo setup.

I say go for it!

 

Why would you want to mount the turbo in the rear?...your only boosting an H22, it will fit in the front; seen it done a few times.