SOHC with DOHC internal compression ?

oh3moparneon · Post by **oh3moparneon** » Fri Apr 29, 2011 6:45 pm

Ok so, I was reading the sohc build up in the stickied threads and it talks about using dohc bottom end parts to raise compression. Can I use srt pistons and rods then? I was told by a friend that I cant because it will increase the rod stroke and hit the valves and head. Is this true? Or can I use these to raise compression?

ZeroChad · Post by **ZeroChad** » Fri Apr 29, 2011 8:09 pm

SRT pistons have a different pin height, so they aren't compatible. Your 1gn DOHC pistons and rods will work, netting you around 10.5:1 SCR.

oh3moparneon · Post by **oh3moparneon** » Fri Apr 29, 2011 8:25 pm

Ok that answers my question thanks

Viper_DNA · Post by **Viper_DNA** » Sat Apr 30, 2011 10:43 pm

so if there like a trick to this or something
or will the parts fit like if they were stock ones but better... reason why im asking is because i dont know anything about cars but if this is possible and the parts will fit like stock with out modifications i think i will be interested in this...ill would buy all the pieces apart and take the car to a local shop and have them rebuilt it and tell then this are all stock parts or do ya think they would notice or would they have to do any special modifications on order to do this?

how much faster should my car get? cuz right now im getting beat by every single car in the street for real...all stock hondas and automatic cars everything..its very sad thats why im considering on putting $$$ into my engine

im also considering on doing head work
getting my stock head polish and putting magnum springs with comp 400 cam ..i havent yet decided on the valves and rockers yet...any recomendations?

what yr should i look into for 1st gen dohc pistons and rods? to put in my 2000 dodge neon? and would this parts have to be stock or can i order this same part but after market like eagle rods and je pistonds?

are dodge neons fast?..lolz cuz mine aint so if i dump in a bunch on money will it be fast or would i be wasting my money?

any info will help..thank ya!

NiteHawk · Post by **NiteHawk** » Sun May 01, 2011 2:17 am

wow...how to answer that last post......................

ok, SOHC motors with DOHC internals have a higher compression because of the difference in the head... the combustion chamber is different between the 2, with the SOHC having the tighter chamber.

for instance...i rebuilt a motor for my car using 9.0:1 DOHC pistons, which will yeild me right about 9.4:1 using an SOHC head.

eagle rods and JE pistons is a better option hands down...they can handle abuse much better than stock internals.

Unfortunately, you wont get 10.5:1 out of stock DOHC compression pistons in an SOHC...maybe closer to 10:1 is more reaslistic.

if you dont have a magnum head, dont bother with headwork because the non mag head doesn't have much room to be opened up. find a GOOD magnum head and have that worked instead...

neons are not fast...lets face it, it's a 4cylinder economy car...they can be made to be not so slow though, lol..

if you want to be fast, i hope you have deep pockets kiddo...cause you're gonna need it...i've invested over $12k into my turbo setup and i'm only looking at 400-450 at the wheels...

oh yeah...and raising compression, you're going to have to run higher octane fuel.....hope you can afford 91+

oh3moparneon · Post by **oh3moparneon** » Sun May 01, 2011 5:07 pm

I run 93 anyways in mine and Im starting to think about doing the 2.0 turbo build that I got the 2.4 dohc for again. I was told alot by esteinmaier with what I need to do to run it and run it right, so idk. I know I need new rods but have been told that the stock pistons will hold up just fine. So I just have to figure out what I want.

esteinmaier · Post by **esteinmaier** » Sun May 01, 2011 7:35 pm

Stock rods and pistons both do pretty well, but all it takes is a flash of lean fuel or advanced timing to turn them into trash.

oh3moparneon · Post by **oh3moparneon** » Sun May 01, 2011 7:49 pm

So I mean unless the tune I would get from duster doesn't flux at all I would be ok on stock sxt rods and pistons

NiteHawk · Post by **NiteHawk** » Mon May 02, 2011 10:24 pm

within reason, yes... if you want to go past 250-300 i would recommend internals... erick has seen stock motors put down 300 IIRC, but at that point, i consider that a risk, because like erick said, all it takes is it going lean or a hair too much timing and you're going to be replacing the motor...

and now that i re-read my previous post.....my numbers are a bit off... i bought 8.6:1 dohc pistons which are 9.0:1 in an SOHC and I had the head milled .030" to bring it up to 9.4:1

stock DOHC pistons in an SOHC would yield about 9.7:1 +/- a point or two.....

oh3moparneon · Post by **oh3moparneon** » Mon May 02, 2011 11:05 pm

Honestly I want to run stock hp at about 230... I dont wanna be the fastest just stock srt, I know I will want more once Im there but I will cross that bridge when I come to it. So the stock internals can hold for that much at 10-12 psi.