M20 e to i head swap questions

[kendogg]

OK, guys, I have to do some kinda presentation on something performace related for my street legal performance class at school, and it can't be something out of the course book, so I figured what a perfect topic! Is there any other place for good info besides strictlyeta.net? I plan on using that as a major resource for my project. Basically, I need a 10 minute or so presentation, I decided to do powerpoint. What a way to bore all those old chevy and rice burner kids, with our awesome bavarian torque monsters, lmfao.

[kendogg]

Also, if anybody can help me out, and give me any kind of sound files, of like, an e30 revving, or anything, ti'd be greatly appreciated, since I wanna add those into my powerpoint for some pizzaz (sp?), lol. I'd love to show you guys what I have now, but, this won't let me upload a powerpoint file.

[ironman502]

No sound clips, but here's a short video of a high powered e30 that I found at school. Hopefully the link works; I can't test it here at home since we have dialup .

http://www.hv.ssf.scout.se/~anders/r...llmangorla.mpg

[MR 325]

www.strictlyeta.net should have plenty of info for you

[kendogg]

OK, guys, I have to do some kinda presentation on something performace related for my street legal performance class at school, and it can't be something out of the course book, so I figured what a perfect topic! Is there any other place for good info besides strictlyeta.net? I plan on using that as a major resource for my project. Basically, I need a 10 minute or so presentation, I decided to do powerpoint. What a way to bore all those old chevy and rice burner kids, with our awesome bavarian torque monsters, lmfao.

thanks!

[hotghias]

r3vlimited has some exhaust sound clips.

[kendogg]

r3vlimited has some exhaust sound clips.

Thanks. I'll check that out. from what I'm reading, it sounds almost simpler, adn cheaper, to just buy an i car, and put the eta crank and rods in.

[hotghias]

correct. it would be easier and cheaper to start with an i, but it's not just swapping rods and crank. you'd have to swap or machine the pistons, too. and you may not need to swap rods.

[kendogg]

correct. it would be easier and cheaper to start with an i, but it's not just swapping rods and crank. you'd have to swap or machine the pistons, too. and you may not need to swap rods.

Why would you need to change pistons? Isn't that why you's swap rods instead?

[kendogg]

has anybody here done this, and dyno'd they're car afterwards? I have all the procedure, and everything, etc. I just need some results to post in my presentation. I've got specs on both the e and i engines, parts list, basic instructions, does anybody else ahve any suggestions for me? I think I'm gonna piost a small bimmer video on the last slide, too, to piss off more of the ricers and rednecks, too.

[driftZ31]

ive done it .... make sure you shave the head all the way down ... take it to a machine shop. it cost me about 75 bucks to have them do it and it took 3 days. Also look into a 524td crank. its cast so its alot stronger than the e or i crank. i never got my car on the dyno but the gains are very noticible!

[uberpanzer]

OK, the eta crank is fine UNLESS you plan on going with forced induction later.

kendogg, you don't seem to have gone through ALL of Fred's site yet. He has the reasons spelled out as to why you need the parts he lists. The pistons are different in the two motors, and so are the comb. chambers. There are also pistons out there lke the ones from Metric Mechanic that have cut-outs in the tops of the pistons so if your timing belt ever goes (usually a big fear of most INFORMED M20 owners), the valves won't bash themselves to death (or the death of the rocker arms) on the pistons. Basically, custom pistons are the way to go to help in a couple of different areas (timing belt mishap, compression ratio, re-use of rods).

Fred has a dyno sheet on the 9th page of his e-to-i write-up, but he wasn't happy with the motor at the time and has since tweaked it a bit more.

BTW, it is actually best to start with the '88 325. This is the Super Eta that has the 'i' head and pistons already, the eta block and crank, but it lacks the 'i' cam and valve springs. It could also use some computer tweaking. Oh, one other good thing about it if you are buying the whole car instead of just a motor....the metal bumpers can be directly swapped for plastic ones with no mods/molding needed....'88 being the only year for this.

[kendogg]

[QUOTE=uberpanzer]OK, the eta crank is fine UNLESS you plan on going with forced induction later.

kendogg, you don't seem to have gone through ALL of Fred's site yet. He has the reasons spelled out as to why you need the parts he lists. The pistons are different in the two motors, and so are the comb. chambers. There are also pistons out there lke the ones from Metric Mechanic that have cut-outs in the tops of the pistons so if your timing belt ever goes (usually a big fear of most INFORMED M20 owners), the valves won't bash themselves to death (or the death of the rocker arms) on the pistons. Basically, custom pistons are the way to go to help in a couple of different areas (timing belt mishap, compression ratio, re-use of rods).

Fred has a dyno sheet on the 9th page of his e-to-i write-up, but he wasn't happy with the motor at the time and has since tweaked it a bit more.

BTW, it is actually best to start with the '88 325. This is the Super Eta that has the 'i' head and pistons already, the eta block and crank, but it lacks the 'i' cam and valve springs. It could also use some computer tweaking. Oh, one other good thing about it if you are buying the whole car instead of just a motor....the metal bumpers can be directly swapped for plastic ones with no mods/molding needed....'88 being the only year for this.[/QUOTEWell,

I read most of the site, and yes, I knew that the 524td crank was better, as you said, because it is forged. I understand why he listed the parts, and I understand what can be done with the motor to make it better to start with. I'm just trying to put together a pretty basic less than 8 minute presentation for my class, thast all. But, in theory, if your going to go FI, don't you want a lower compression anyways, meaning, that if you could set it up so as the pistons are never close enough to the valves to ever be a problem (not sure if that can be done, not too sure of exact specs of valve lift/piston heighth). Am I right? Or, is there a limit where too little compression is bad.