8v 2l Twin Charged -my Little Project

[ToonRboy]

Well, the term "sleeper" usually means a mundane looking car that's very quick/fast. The GTV6 looks are anything but mundane. It may not be very quick, but they are fast. Nice story lenus on your experience with the Skyline (Nissan Skyline).

Yes GM has been using the Eaton in a lot of applications that are quiet. However, I might want to point out that they're running .5 BAR or so, rather than a little over 1.3 BAR, as buzzed is planning to do.

Biba - BOV is an acronym for Blowoff valve .

BTW - Can't wait to see this project come to fruition buzzed, it is truly different.

[slyalfa]

I would say there are 2 types of working Blowoff valves . (and (non)working for show type)
one type is a safty or to keep the boost in spec with the rules and you never wnat that type to blow. as it will take a long time to recover.
the 2nd type opens just to keep the turbo from surging when you pop closed the buterflys on a shift. This can save the turbo. A bad surge can kill a turbo. If done right it will also help keep the turbo up to speed, best used with some sort of ant-lag in the ECU (at the expense of valve life). they normaly vent back to the intake or the exhaust so there is no noticable sound. now for show type well they might work IF set up right.
and I like how they have a megaphone on them to even make it louder....

[lenus]

Nissan Skyline..

[5yearplan]

BOV stands for blow-off valve, when the throttle body is closed, it releases the pressure created by the turbo/supercharger into the atmosphere.

[ToonRboy]

Right, right, and right.

The main reason is to prevent stalling (from the surge) of the impellor, and having to reach speed again once throttle is re-applied after a shift. Don't really need 'em on an automatic car ('cept the new drive by wire ones that do pop the throttle on shifts).

The BOV helps the impellor maintain rpm so that one maintains boost more effectively between shifts. Point being, most stock turbo cars don't have one installed and if someone drives up with a BOV whistling dixie, you've kinda' lost your "sleeper" status.

Anyway,

Anything new to report on this build?

[Greg Gordon]

I like the sound of a Bosch blow off valve. It makes a "whoosh" sound you can hear, but it's not loud.

The G.M. Eatons are quiet primarily due to the intake design. The supercharged Cobalt has 12 pounds of boost, and its supercharger is very quiet when off boost. It could certainly be quiet in this application if that was a priority.

Greg
P.S. I will be off this forum for about a week. I hope to see some of you folks in Chicago!

[5yearplan]

I've always wanted to get a louder supercharger, and a quiet exhaust system, I like the sound of the SC whine!

[buzzed]

Update!

engine dismantled, cleaned partially painted and measured up ready for machine shop. I ducked out to a mates place and we machined up the sleeves to accept the orings.

This is a ****ter motor to prove the concept, I'm using 2l twinspark pistons and 8v rods. Once I prove it out, the engine is being put aside and a full house one will be built with the forged internals that just turned up today, plus a Vin sharp mono sleeve, and a girdle I am designing to hold the bearing caps in in the engine!

Engine should be assembled by end of August.

Stay tuned!

[Biba69]

Buzzed, looking good. I googled Vin Sharp and Pace Engineering to see if he/they have a website. Does he? I'm just curious to see what his mono sleeve looks like.

It sounds as if the lower end of the Nord block is going to be quite sturdy!

Biba

Umm, isn't using TS pistons cheating? You'll have to add TSP's to whatever name you come up with.

[James1750]

Quote:

Originally Posted by Biba69 Buzzed, looking good. I googled Vin Sharp and Pace Engineering to see if he/they have a website. Does he? I'm just curious to see what his mono sleeve looks like. It sounds as if the lower end of the Nord block is going to be quite sturdy! Biba Umm, isn't using TS pistons cheating? You'll have to add TSP's to whatever name you come up with.

[buzzed]

Vin would not have picks up yet the his setup as its still early stages of development.

TS pistons are probably less cheating than the forged custom pistons and rods I have for the REAL build. The TS pistons just give me a cheap starting point. Actually I considered machining the tops of the stock pistons as well, reckon that is feasible also.

Everything is now being balanced as we speak, and head is being reco'd also, nothing special mind, I'm not going bigger valves just yet. I want to be in a position where I am not scared to lean on it...I really want to find the limits and then work on the weak areas.

For anyone interested, the internals are painted to reduce corrosion and also to improve oil return to the sump, apparently it does help (probably bugger all...but hey, it looks good).

[GTV-GR]

I'm not a great fan on the paint issue. If that thing chips is off to the oil pump.

[ToonRboy]

I thought maybe the paint leprechaun had struck!

'course I didn't want to state the obvious - it could'ave been a red teflon coating or something...

More than chipping, it'll get dissolved into your oil, in vinyl-like bits and clog up your oil pump strainer (to say the least).

Quote:

...painted to reduce corrosion and also to improve oil return to the sump, apparently it does help (probably bugger all...but hey, it looks good).

[buzzed]

My engine builder has been doing this for 30 years to Lambo's without issue, it's no ordinary paint and does not chip or disolve. It just stays put and sends oil back to the sump a poofteenth quicker. Personally I reckon it looks good too.

It certainly makes it easy to keep clean during the build.

Anyhow, stay tuned, it's all happening quite quickly now. The engine should be reassembled quict quickly, then there will be a delay after that for a bit while I move house.

cheers
Mike

[Duk]

Quote:

Originally Posted by buzzed Personally I reckon it looks good too.