Engine Build Thread

[kpjc4eva]

Originally Posted by Chuck33079

A larger displacement motor will spool any turbo quicker. As far as it being for low end power and no top end, that's up for debate. I would think that cam profiles, any head work, and turbo sizing would be more of a factor in determining the shape of the curve. You'll definitely make more power down low, but I don't think we've seen enough stroked VQ37s to determine if they die off up top.

If I'm remembering correctly the stroker kit from GTM shortens your revolutions. So if you bought a stroker kit, for example and my understanding, and managed to stuff a 71mm turbo down I think its going to need more time to spool up, right? So our cars are what 7300rpm? If its full boost at 6500 hundred and the stroker kit knocks out the revolutions to 7000 rpm, what exactly is the point of a stroker kit? The 71mm turbo will never be fully used. I don't know but thats my understanding of a stroker.

Boring out would increase the revolutions. I see that MORE beneficial. IF IM UNDERSTANDING THIS. Again, I could be talking about of my ***.

[Chuck33079]

Spool isn't necessary a function of rpm. It's a function of exhaust gas volume and velocity. Higher rpm would provide more exhaust gas, as does greater displacement.

[kpjc4eva]

Originally Posted by Chuck33079

Spool isn't necessary a function of rpm. It's a function of exhaust gas volume and velocity. Higher rpm would provide more exhaust gas, as does greater displacement.

right.
so the revolutions are important. the more the higher volumes of gas and so forth as you stated.

but you going to tx2k13? see your from houston.

[Chuck33079]

A larger displacement engine will spool up a large turbo at a lower rpm than a smaller one. All things being equal, you'd end up at a similar peak power, with the larger engine producing more area under the curve. Also, unless you've chosen a turbo way too large, it's not hitting full boost at redline. You're more likely to see full boost between 3500 and 4500 rpm depending on turbo size.

[bullitt5897]

Originally Posted by elliotty

I think there have been a few GTM customer vehicles with the stroker motors as well. I am mostly interested in how that would affect torque and turbo spool. I am guessing I might need to upgrade the GT28s to something larger to really utilize the increased displacement. Any thoughts?

DIGItonium - I think you could manage heat well with an upgraded radiator, which for reliability reasons, I would probably want to do if building the motor.

Being one of the stroker kit owners:

The larger displacement increases the exhaust gas flow. What you have to take into consideration is what turbo or SC'er is the correct size for the displacement. I am running two GTX35R turbos on the 4.5L and it has a similar spool response as the GT28's did on the stock motor. check the video below at 53 secs in you will see my low boost setting on the stock intake manifold. This should give you an idea of what a proper sized turbo to displacement should look like.


With the stroker kits if you go 4.2L you will not have to sleeve the block. However, with the 4.5L you do and this comes with the expense of much more HEAT!!! We had to go with a full race radiator to make it manageable. I still have to talk to Sam to see if there is a way to save my A/C on my build. I believe he removed the A/C compressor so I will need to find a way to squeeze that bugger back in between the cooling mods.

A 4.2L you could get away with the CSF radiator and I highly recommend it! Great Product and Great Customer Service!!!

[DIGItonium]

Originally Posted by elliotty

DIGItonium - I think you could manage heat well with an upgraded radiator, which for reliability reasons, I would probably want to do if building the motor.

Yea, part of the upgrade is the CSF radiator. I didn't list it since I'm primarily focused on the engine.

Those who built their motors, anyone got away with reusing the VVEL portion? I think I read it least one person did it without any issues. I was actually thinking about building the block and reusing/upgrading my heads.

@Mike, any word on the lower manifold adapter? My plenum is still boxed up in the garage.

[elperuano]

Originally Posted by Bullitt@UAMotorsports

Being one of the stroker kit owners:

The larger displacement increases the exhaust gas flow. What you have to take into consideration is what turbo or SC'er is the correct size for the displacement. I am running two GTX35R turbos on the 4.5L and it has a similar spool response as the GT28's did on the stock motor. check the video below at 53 secs in you will see my low boost setting on the stock intake manifold. This should give you an idea of what a proper sized turbo to displacement should look like.


With the stroker kits if you go 4.2L you will not have to sleeve the block. However, with the 4.5L you do and this comes with the expense of much more HEAT!!! We had to go with a full race radiator to make it manageable. I still have to talk to Sam to see if there is a way to save my A/C on my build. I believe he removed the A/C compressor so I will need to find a way to squeeze that bugger back in between the cooling mods.

A 4.2L you could get away with the CSF radiator and I highly recommend it! Great Product and Great Customer Service!!!

What was the upside of goin 4.5? More low end torque and power?

[Nixlimited]

Originally Posted by Bullitt@UAMotorsports

With the stroker kits if you go 4.2L you will not have to sleeve the block. However, with the 4.5L you do and this comes with the expense of much more HEAT!!! We had to go with a full race radiator to make it manageable. I still have to talk to Sam to see if there is a way to save my A/C on my build. I believe he removed the A/C compressor so I will need to find a way to squeeze that bugger back in between the cooling mods.

A 4.2L you could get away with the CSF radiator and I highly recommend it! Great Product and Great Customer Service!!!

Why does sleeveing the block create so much additional heat? Do you think it was worth it to add the additional .3L given the heat issues that come with it?

[Mr.Squeeze]

Originally Posted by DIGItonium

Yea, part of the upgrade is the CSF radiator. I didn't list it since I'm primarily focused on the engine.

Those who built their motors, anyone got away with reusing the VVEL portion? I think I read it least one person did it without any issues. I was actually thinking about building the block and reusing/upgrading my heads.

@Mike, any word on the lower manifold adapter? My plenum is still boxed up in the garage.

8000 miles on my built engine and I didn't replace VVEL .

I have a couple of things to add for now I'm down in Florida at the PRI show .

No need for nismo oil pump stock is fine .
There is a Haltec unit coming out for the 370 I just saw it
CP does not make pistons for the 370 it will have to be custom set .

[elperuano]

Originally Posted by Mr.Squeeze

8000 miles on my built engine and I didn't replace VVEL .

I have a couple of things to add for now I'm down in Florida at the PRI show .

No need for nismo oil pump stock is fine .
There is a Haltec unit coming out for the 370 I just saw it
CP does not make pistons for the 370 it will have to be custom set .

What part of Florida r u in now, and more importantly are u here with that built monster?? Lol

[Chuck33079]

Originally Posted by Nixlimited

Why does sleeveing the block create so much additional heat? Do you think it was worth it to add the additional .3L given the heat issues that come with it?

Usually it's the combination of the thicker iron cylinder lining trapping more heat and the lining protruding further into the water jacket around the cylinder bore.

[bullitt5897]

Originally Posted by DIGItonium

Yea, part of the upgrade is the CSF radiator. I didn't list it since I'm primarily focused on the engine.

Those who built their motors, anyone got away with reusing the VVEL portion? I think I read it least one person did it without any issues. I was actually thinking about building the block and reusing/upgrading my heads.

@Mike, any word on the lower manifold adapter? My plenum is still boxed up in the garage.

Call SAM... I know he has the production unit in hand... the first one is being installed as we speak.

Mike

[bullitt5897]

Originally Posted by elperuano

What was the upside of goin 4.5? More low end torque and power?

Going to the 4.5L allowed me the displacement that I needed to reach my goals and beyond... Like they say there is no replacement for displacement! lol

[bullitt5897]

Originally Posted by Nixlimited

Why does sleeveing the block create so much additional heat? Do you think it was worth it to add the additional .3L given the heat issues that come with it?

Its not that sleeving the block alone adds more heat its a combination of factors that have attributed to the additional heat. Remember I am keeping the high RPM redline with alot more mass being rotated in my engine. The material that used to act as a heat sink behind the cylinder walls is no longer there... Larger moving parts with a greater surface area along with less material in the block will result in a hotter engine.

[bullitt5897]

Originally Posted by Chuck33079

Usually it's the combination of the thicker iron cylinder lining trapping more heat and the lining protruding further into the water jacket around the cylinder bore.

another good answer.