engine conversion

[titan2175]

I have a 93 dodge stealth SOHC and am looking to convert the egnine to DOHC. What are some things i have to do to convert it, where can I get them, any idea or help would be greatly appreciated.

Thanks

[Stealthee]

You need DOHC power steering lines, DOHC ac compressor, the altenator I think is different. Then you will need a DOHC ecu and wiring harness. There are a couple write ups out there that will tell you everything you need to know, just got to find them.

[Linebckr49]

Originally Posted by titan2175

I have a 93 dodge stealth SOHC and am looking to convert the egnine to DOHC. What are some things i have to do to convert it

well someone correct me if i'm wrong, but i'm not entirely sure that you can convert a SOHC engine to a DOHC engine. The conversion you are speaking of regards the obvious head switch. Now it might be as simple as switch the heads, but i'm not sure about the intake plenum and other sorts of things. As Stealthee said, some of the engine accesories (AC, alt, pwr steering) will be different. But the basic premise behind the conversion is that you want the power of DUAL overhead camshafts, as opposed to just the SINGLE overhead camshaft atop each set of heads. So obviously, you will need the DOHC heads from a DOHC engine.

As to the specifics, search the FAQ and www.3si.org also has an abundance of material. But before doing the switch/conversion, you might consider just selling your car and getting a VR4, the ultimate upgrade!

[Stealthee]

You cant just swap the heads. The blocks them selves have a different casting. Besides even if just swapping te heads is possible you HAVE to change teh pisotns because they are not clearanced for 4 valve heads. I have a halfway torn down SOHC motor in my garage right now and the clearances are totally different. SO by the time you tore the motor apart and swapped pistons, rods(because DOHC's have forged rods), crank(DOHC's also have a forged crank), and reassembled it, swapped in the DOHC upper and lower plenum it just wouldnt be worth that much hassle, hence why you need a complete DOHC motor. There are several people who have succesfully completed the swap. There are a few who have swapped to DOHC-TT from a SOHC. A 3si member close to me is starting that exact conversion this weekend and they will be taping. If you decide on the swap, be prepared. Make sure you have all teh parts necesary and the know how of what you are undertaking.

[jdridah]

hey stealthee, u said that the DOHC engine had forged piston rods and crank right? are u talking about only the TT? or even the SL? and if so.. what about the Piston heads? are they forged to? hmm do you think its safe to put a small turbo on a stock DOHC? im thinking 5-6lbs?a

[Stealthee]

the crank and rods were forged in all DOHC's. The piston were always cast. A stock 10:1 DOHC can handle boost just fine but if you are swapping from a SOHC your best bet is to buy a whole TT motor and accessories. A single turbo is 100% custom where as people who already have a DOHC can just swap on stock TT parts.

[jdridah]

yeah i have a stock DOHC.. and if i can sqeeze 5-7lbs of boost into it without any worries.. than im gonna look into doing it... hmm what kinda HP gain would u guess from 7lbs of boost? ( on the DOHC) just a guess?

[GritMaster]

between 50 an 70.