20v Blacktop 7AG class project

[Esenpai]

Hello fellow clubbers!

I'm an auto tech student and I'm taking a automotive engine engineering class.
As part of the class we are to design or build and I've been having trouble sourcing engine design information on the web.
I'm the only person in the class doing a Japanese motor everyone else is like FUUU YEAH V8s!
I wanted to do something different and probably picked the most difficult of all the engines to do my project on within my class.
if it turns out I can't get enough info on the 7A block then I'll be doing just a plain blacktop 20v 4AG.

I'm looking for stock numbers on both engines and then will be adding aftermarket pistons and things to it after I get stock numbering.
Once my project is done I'll post up all my finding and info to the forums for future reference of anyone that needs them.

So far this is the info I have about the hybrid engine. Please feel free to correct me if I'm wrong Everything I have here was taken from the interwebz and I don't know how correct it is..

4A & 7A Stock bore 81mm (3.18in)
7A Stock Stroke: 85.5mm (3.36in)
Clearance volume: 0.3mm?(don't know if this is correct)
Blacktop Chamber Volume: 37.8cc
7A Deck height:206mm
Gasket thickness(using TRD headgasket: 0.8 uncompressed to 0.6 compressed

Info that I'm not sure is correct or true to stock figures:
Piston Dome: 4.7 (wasn't given a unit of measurement source 86garage)
Piston Height: 30.5mm (1.2in)
Comp Height: 30.5mm (1.2in)

Info I need:
Stock Blacktop Piston top volume:
Stock Blacktop Piston Valve Relief:
7A Crevice Volume:
7A Chamfer Volume:

If I could get the blacktop crevice and chamfer volumes too that would be great.

Right now we are trying to calculate C/R and piston speed.

Any other info that you think may be beneficial to me if you're willing to share it would be greatly appreciated.

Thanks guys and girls.

:thumbsup:

[Esenpai]

No help? Don't we have any crazy engine builders who can spare some stock specs?

[ae86-20v-black]

http://www.s-86.com/technical_articles.php

i hope that help you for info in the 20v engine!!!. my car is 4age 20v blacktop engine.

[yoshimitsuspeed]

http://mr2oc.com/showthread.php?t=206960

http://mr2oc.com/showthread.php?t=355537

http://mr2oc.com/showthread.php?t=462191

http://mr2oc.com/showthread.php?t=454795

http://www.mr2.com/forums/mk1-engine-ta ... iming.html

http://www.mr2.com/forums/mk1-engine-ta ... ction.html

[Esenpai]

Looks like I'll be signing up for mr2.com

thank you my good sirs!

[oldeskewltoy]

the metal head gaskets do not compress further then their listing... .8mm is .8mm when compressed, while .5mm is .5mm when compressed.

I STRONGLY recommend you use a piston stop when determining TDC....... EVERYTHING else is less accurate

Please explain further chamfer volume, crevice volume is the area between the piston and the cylinder wall, down to the first ring. You will need to know the OD for your pistons(once expanded) and your cylinder, and finally measure down from the deck.

Speaking about deck*, 4A deck is .015" - deck = measurement from edge of piston to top surface of block

[Esenpai]

the metal head gaskets do not compress further then their listing... .8mm is .8mm when compressed, while .5mm is .5mm when compressed.

I STRONGLY recommend you use a piston stop when determining TDC....... EVERYTHING else is less accurate

Please explain further chamfer volume, crevice volume is the area between the piston and the cylinder wall, down to the first ring. You will need to know the OD for your pistons(once expanded) and your cylinder, and finally measure down from the deck.

Speaking about deck*, 4A deck is .015" - deck = measurement from edge of piston to top surface of block

Curious why people say they compress then. That was something I didn't know thanks for that.

This is actually an all n paper project. I wont start building the engine for quite awhile.
I'm just currently trying to gather info on the two engines to make the theoretical design of the engine. or you could just say im designing the engine on paper.
Isn't there a set spec range for chamfer and crevice volume of toyota engines with stock everything?

do you by any chance know the 7A deck? since Im going to be using a 7A block for my project I know its more then the 4A. though when I build the actual engine I will be decking down to the 4A spec. but for now I'm just trying to get the stock specs as that is was the professor is asking of us now.