rebuilding my 420a questions

Brian O Conner · May 9, 2011

I am rebuilding a Eclipse 420a. I bought it with a blown head gasket as a project car. My buddy and I took the engine out & apart this is what we found. T3/T4 turbo, Turbonetics intercooler with a cool air intake, custom welded headers and exhaust, It was bored over 0.40, had JE forged pistons, Eagle rods, Eagle crank, Arp head bolts,resurfaced head, Apexi SAFC II, Short shifter, Fidanza aluminum flywheel, aftermark rotors & a suspension cant identify. So far I bought Crower stage 2 turbogrind cams, took the head with parts to the local machine shop. Parts checked okay. Had him order BC Titanium valve springs with recaps, SBI lifters, SBI rockers, SBI guides, Pep valves, cometic head gasket, SBI locks, main bearings. Things I am going to get Fidanza Camgears, MSD wires & coilpack, NGK spark plugs, 490cc Accel injecters, walbro fuel p, Airtex water pump, Mellin high volume oilpump, OBX intake mani, Act Race 6 pad clutch, Carbon fiber hood, take off catalac converter, 94 gas with octane booster, Brad Penn performance oil with zinc. question #1 The machine shop checked all the parts but the turbo should I get that checked out somewhere the reason for this is because he doesnt do turbos. question #2 is 490cc injecters good, too lean or to rich for 20 psi of boost. Question #3 could I use a small shot of nitrous or will I need to O-ring my head. Question #4 I am getting it engine dynoed but what hp will I expect to see with 20psi of boost and all of those mods if stock is 145hp. Question #5 stock rpm redline is 6800 what should I expect to see if it is finished. Question #6 stock 1/4 times are 16.2. With toyo tires and good shifting what could I get. Seriously thank you for helping me awnser these questions. Just looking for friends who are into cars and guns. Also anyone from Indiana please add me.

2gProjectCar · May 9, 2011

Question 1: Start by checking the turbo for shaft play (movement up and down, left to right) if there is any I would go ahead and have it rebuilt. Also spin the shaft by hand and listen for any scraping/scratching coming from the inside, this would mean a rebuild might be needed too. You wouldn't want to dump a bunch of money into the motor just to blow a turbo seal and mess everything up do ya?

Question 2: Looking at what mods you have, I'm 99% sure that 490's will cause you to run really lean at that high of boost pressure unless you have a near perfect tune. I'd personally go somewhere in the 750-1000cc range. As long as you have something to tune with, to big of injectors won't hurt and they leave room to support future upgrades.

Question 3: To be honest, I don't know much about nitrous so i can't answer that one. I'm sure someone on this site can though.

Question 4: Many people ask this question and they all get the same answer. It's hard, if not impossible, to give an accurate hp estimate because there are so many variables that factor into it such as the turbo size and how decent the tune is. But if I had to guess, I'd say you'll get around 375 whp, and that's a low guess.

Question 5: This is another question that's hard to guess. But I'd say if all track conditions are perfect and you have The Stig driving probably somewhere between a low-12 to mid-13

And on a side note, something you might want to check is the exhaust size. If the exhaust is to small then you'll create to much back pressure on the motor that will rob you of power.

Any wisemen disagree with these answers?

Josh97eclipse · May 12, 2011

Good luck finding the obx intake manifold. If you find one let me know

cimotorsports has them but there out of stock right now

WickedBlk95GSX · May 12, 2011

Yeah I was going to say imo when building a 420a cimotorsports.net is the best site to find anything you will need.

Josh97eclipse · May 12, 2011

WickedBlk95GSX said:
Yeah I was going to say imo when building a 420a cimotorsports.net is the best site to find anything you will need.

That is true.....but they SUCK on shipping, they take forever to ship your order. :ohdamn:

Brian O Conner · May 12, 2011

yeah I am a vip member on there site I have spent 2000 dollars. but my review of there site they got the most organized site. have more parts than anyone for those cars. they specialize in the 420a. problem they dont have a legit phone system. they take way to dam long to ship an order. there prices are really dam high except for there melling high volume oil pump for some reason that part was really the cheapest I have ever seen them go.

Josh97eclipse · May 12, 2011

You got that right. Except i bought my melling oil pump at autozone for $96

WickedBlk95GSX · May 13, 2011

Josh97eclipse said:
That is true.....but they SUCK on shipping, they take forever to ship your order.

Yeah that is very true, I only got something from them once and it took like 2 months to get. I was hoping that wasn't normal.

Fotowntalon · May 13, 2011

Josh97eclipse said:
Good luck finding the obx intake manifold. If you find one let me know cimotorsports has them but there out of stock right now

I hope this is a troll/joke... OBX are everywhere, mainly because they are horrid manifolds, very slight upgrade from stock. actually there are a few in the classified section, or about a million on EBay if you want to stick with that route.
I take it back those ones in the classified must of sold anyways there is still some on ebay

dboyle23 · May 13, 2011

If you are going to use an SAFC, then keep your injectors at 680cc max, SAFC's don't work with anything higher.

Also, you'll want some ARP headstuds so you don't blow another headgasket.

bo0st · May 13, 2011

Brian O Conner?? is this the real one? hahaha just kiddin and yeah man with good shifting + some nitrous you can do 12's

Brian O Conner · May 13, 2011

By the way the OBX intake manifold is really dam rare right now. You cant find it on ebay or the other 5 sites I could find it. THe funny thing is I found a member on here that was selling one that lives only 50 miles away so I drove to his house and bought it in person we even played there football team in a state game I could not believe it. Also boost I give you props no one else has recognized my name yet besides you and one other person. As Arp head studs and bolts go I already have those.

Josh97eclipse · May 13, 2011

Fotowntalon said:
I hope this is a troll/joke... OBX are everywhere, mainly because they are horrid manifolds, very slight upgrade from stock. actually there are a few in the classified section, or about a million on EBay if you want to stick with that route.
I take it back those ones in the classified must of sold anyways there is still some on ebay

I have looked on ebay there were none as of last night. I want another one when i get the money.

Fotowntalon · May 13, 2011

1995-1999 ECLIPSE NON-TURBO 2.0L 420A INTAKE MANIFOLD | eBay

Also was it Brian Speilner or something, we didn't realize he was O Connor till his 420a was destroyed

Josh97eclipse · May 13, 2011

Yea but that manifold is not obx and the welds look like pure crap.

Fotowntalon · May 13, 2011

so does OBX's, you just don't have a bigger picture of it 99% of obx is pure crap, they are a knock off company, with horrible quality control. There intake manifold is already prone to cracking, horrible fitment problems. Bullet got one a while back and while he did gain 3whp over stock, it was through some extensive porting on his own accord.

To prove my point, and also something you should read just to help with installation read this.
2GNT.com - OBX_Intake_Install

uscav_scout19d · May 14, 2011

Josh97eclipse said:
I have looked on ebay there were none as of last night. I want another one when i get the money.

RSAperformance has it $149.00
CI Motorsports has it $209.99
ERZ Performance has it $144.99
ERacingzone has it $144.99
All I did was just go to GOOGLE shopping and typed in 420a OBX racing intake manifold.... :thumb:

BigNugg99 · May 14, 2011

i didnt see an upgraded throttle body on your list... i would look into that. there is a page that describes how u can get a junkyard mid 90's jeep 4.0 throttle body and convert it to work on our 420a. they are about 55mm and can be ported. also i would suggest to go the true o' conner route with a full stadalone engine management system... the one usedby alot of 420a owners is megasquirt. they are affordable and provide great control of spark and fuel or u can use it just for fuel (piggyback)

uscav_scout19d · May 14, 2011

BigNugg99 said:
i didnt see an upgraded throttle body on your list... i would look into that. there is a page that describes how u can get a junkyard mid 90's jeep 4.0 throttle body and convert it to work on our 420a. they are about 55mm and can be ported. also i would suggest to go the true o' conner route with a full stadalone engine management system... the one usedby alot of 420a owners is megasquirt. they are affordable and provide great control of spark and fuel or u can use it just for fuel (piggyback)

Or do as I am doing and do Haun Racecraft Portfueler and MSD Dis II with boost retard

but I would try the Jeep TB... come to think of it I need to get one too.... :aha:

BigNugg99 · May 14, 2011

and i ran some numbers for u... at a/f @ 11:1, absolute psi @ 13.94 to compensate for altitude in indiana and filter restrictions etc+20psig, bsfc @ .525, max rpm @ 7200 and other stuff you would be looking at about 358whp. this is just a realistic ballpark given a good tune, average optimum air charge temp etc. at 350hp at 11:1 a/f and other varibales you should use aprox 57.42lb/hr or 557.76cc/min injectors (figured at 80% duty cycle)

Brian O Conner · May 14, 2011

RSAperformance has it $149.00CI Motorsports has it $209.99 ERZ Performance has it $144.99ERacingzone. Scout I give you props you think exactly what I do. but the problem is NONE OF THOSE COMPANIES HAVE THOSE IN STOCK AND ARE NOT ON EBAY SO CALL THEM IF YOU DO NOT BELIEVE ME AND BY THE WAY BEING A VIP MEMBER OF CI. YOU WOULD THINK I WOULD TRY THEM WOULDNT YOU? FOR ANYONE THAT READS THIS THE OBX INTAKE MANIFOLD IS VERY RARE AND FOR THE PRICE OF 145 DOLLARS COMPARED TO THE 4G63 BRANDS OF 500 TO 700 DOLLARS I THINK 10 TO 15 HP IS WORTH IT ON A FULL REBUILD MOST DEFINITELY.

BigNugg99 · May 14, 2011

OK the intake isnt instock any where... that sucks. there is a guy here in MI that claims to be able to get an aftermarket intake that is well built and has a good design for $70-$80 on craigslist. i will look into it and see what the brand is and a link for you. In the mean time i was curias to the statement u made about running 94oct+octane booster. IMHO i wouldnt waste your money on the octane booster in a bottle... i personally have never seen any performance gains from them and have read tests from mags and sites that have put them thru a more scientific trail with poor results. i would suggest looking into running E85 if you have places close that carry it.

bo0st · May 14, 2011

BigNugg99 said:
In the mean time i was curias to the statement u made about running 94oct+octane booster. IMHO i wouldnt waste your money on the octane booster in a bottle... i personally have never seen any performance gains from them and have read tests from mags and sites that have put them thru a more scientific trail with poor results. i would suggest looking into running E85 if you have places close that carry it.

I've seen slight gains when running the NoS octane booster. I'm sure you'd have more gains if you were running race gas or had a turbo/nitrous setup (as compared to my N/A build). Made my car a tid bit faster, I was surprised too! haha

BigNugg99 · May 14, 2011

I thought i noticed a difference in my 12a rotary and it may have helped in my 2.2l turbo mopar running 13psi but i just didnt think it was worth it personally. now that we have E85 i think it would be best to tune for that... some say its comparable to race gas (near 105-108oct) and some say its more like 96-98oct but hey its a hell of a lot cheaper than race gas and better than running premium. its cheaper at the pump but u tend to use about 25-30% more fuel. it cools the air some and helps prevents detination allowing you to pull timing and add boost... thats good stuff... we have to worry about winter blends nearing fall/winter time and adjust our tune thougj OMG

)

Brian O Conner · May 15, 2011

You guys sound really cool. The reason why I dont use E85 is because I am a Hick in Indiana and "We gots no E85 heeeaaaah" but we gots da nine four stuff. LOL

not serious but Am serious about the fact we have no E85. By the way isnt E85 Alcohol from corn. But as the octane booster goes. I am very stingy about anything I see a penny on the ground you bet your @zz I will pick it up. 1hp gain you bet I will take it. but a lot on your guys minds right now is why is this guy building up his internals like it is a small block Chevy. Well my biggest problem is I am a R.E.T.A.R.D when it comes to computers. I have an Apexi SAFC 2. But all I know it controls your fuel to air ratio. But anyways I think I have a stock Ecu but I need to go check. Also how much are megasquirt systems going along. the range of the price. also what is a good ecu to buy.

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