98 4v swap questions

[seths99cobra]

so i found a great deal on a 98 cobra 4v motor that was built by houston performance a few years ago. so heres the thing my cobra is a 99 i want to either put my intake and plenum and put on that motor if it will work or just swap the motor as it is into my car but before i buy it i want to see all the options i can so would that motor wire up to my car with out serious problems? or can you guys shed some light on swapping different things on to each motor. that motor supposedly makes 6xx at the flywheel. yalls inputs would be appreciated thanks

 

[bnmc98]

What heads did they use, B or C? B is the dual port and your manifold will not bolt up. Stock the 98s came with IMRCs too, and used a return style fuel system along with coil packs. You could do it but would take some engineering. Doesn't sound like they used stock parts if its making that much HP. Can you give us a little more specs on the motor?

 

[billfisher]

600hp? has to have FI. what blower does it have? if by some small chance it isnt FI, then it likely does not have that kind of power. it takes a special setup to reach that kind of number. there are only a handful out there. its not a street piece at all if it does.

as far as i know there are NO 600hp b headed motors out there. if it makes 600hp why use a crappy 99+ cobra intake?

 

[seths99cobra]

its fi with the b heads. its a houston performance motor the guy said he has all the papers and wat not. cams are custom grind, dished pistons, crank and everything is aftermarket. the guy said it makes 6xx he said 600 to 650 range says it runs off race fuel. he says it jumps time so he pulled it out before it does any damage. he also said the motor is very unstreetable. but i did some thinkin and another guy on another forum said that i should just sap heads. im put the cams in my heads on the race block and spray the house down. the car is fixin to be a weekend warrior. any other suggestions guys. wen i get ready to buy it and see the papers ill let yall guys know wats reallly up wit it

 

[seths99cobra]

has no blower no turbo no gas on it. maybe its just one in a million wicked ass motors. my car stock is no pig by no means so maybe its just one in a million

 

[fast97gt]

I'm a firm beleiver in using the right parts with the right parts, and will see awesome results. For instance I had a 92 firebird formula from gm it made 248 at wheels stock. I did a cam swap using a custom grind with more duration not much more lift than factory, and 2 degrees less lobe seperation. Dynoed it again and saw 308 at the wheels, people think bigger cams, and all that stuff is suppose to make big power but sometimes it'll hurt it.

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[40oz]

if the motor was built for a blower, it probably has lower compression. If you drop it in without a blower, it'll be a dog, cam or not. You'd be faster with your current set-up.

If the fuel injection parts swap and you are going with a blower and spend some time to get it tuned, it might not be a bad deal. Or it could turn into a huge money pit that never runs right

 

[4tun8]

has no blower no turbo no gas on it. maybe its just one in a million wicked ass motors. my car stock is no pig by no means so maybe its just one in a million

Sorry but without a power adder a mod motor is not making 600hp and still running on gasoline.

 

[seths99cobra]

the guy says the compression is 11. something but its all on paper says it runs on race fuel. so idk till i see the papers but its goin to be a few months before i get it. eventually ill have a 2.1 kb maybe some turbos

 

[fast97gt]

maybe its a big bore block? but i think these engines are capable of more than what people think or know. especially if some one has time, money, and capabilitys (shop and tools) and extra parts to eperiment. man there are so many skeptics out there it aint funny. just like the 15% deduct for power loss in the drive train? i find that hard to find, that means the more power you make the more you lose? i dont think its logical. .15x225=33.75hp loss, now .15x450=67.5hp loss. i dont think so. you'll have the same power loss wether its 225hp stock or 450hp, you have the rotating mass either way.

 

[4tun8]

I'm not a skeptic I'm a realist. Show me a mod motor making 600hp on gasoline with no power adder and prove me wrong.

 

[fast97gt]

welp if all goes as planned jr. here just might, were talking a cobra engine here (NA i know). oh i forgot to mention, look at pro-am like the ones who the rolex races and stuff. there 4v engines and i used to do auto glass for a team here in NC there engines put out 575 at the flywheel and "could do better but rules and guide lines take over" from what the engine builder explained.

 

[4tun8]

And this is on gasoline not methanol? Just curious.

 

[seths99cobra]

the guy told me that it wont run well off of 93 just like some cars wontr run off of 87. to be honest i really dont think it makes 6xx i bet it would be in the 5xx range that would be fine with me. cause im gonna hit it with couple stages of gas 200-300 hit. either way it makes more than 300 to the wheels that i make off the gas

 

[ChillPhatCat]

It sounds like quite a bit of work to get something streetable out of that. I say find another engine.

 

[ChillPhatCat]

just like the 15% deduct for power loss in the drive train? i find that hard to find, that means the more power you make the more you lose? i dont think its logical. .15x225=33.75hp loss, now .15x450=67.5hp loss. i dont think so. you'll have the same power loss wether its 225hp stock or 450hp, you have the rotating mass either way.

When you deal with small amounts of power... say less than 500 hp, power loss is pretty much relative... you'll probably see 16% at 100 hp versus 14% at 500 Hp. Once you get up to 600... 700+ Hp, the percentage model starts become less accurate and it starts getting closer to modelling a fixed power loss.

 

[fast97gt]

When you deal with small amounts of power... say less than 500 hp, power loss is pretty much relative... you'll probably see 16% at 100 hp versus 14% at 500 Hp. Once you get up to 600... 700+ Hp, the percentage model starts become less accurate and it starts getting closer to modelling a fixed power loss.

see thats what im screeming i cant stand it when people try to use this method of power loss, i grew up in old school gear head family when things where realistic, what i mean by that your s**t either kicked a** or you lost. also it was a combined loss of parisetic hp loss and d/t hp loss. and combined together was about 35-45hp depending on if you had a/c or a/t or electric w/p etc. you get the idea. so i think some of these tuners are tryin to bulls**t us by saying youll lose 15% nominal no matter what the hp. then it gets some people cornfused, now because when they pump out 470hp at the wheels they add 15% back to that and think they got like 550hp when its closer to ~500hp~. so thats where im coming from. the only real way to measure hp is on a engine dyno, at the flywheel. then at that i woul only subtract what i know from my hp robbers on my car

 

[ChillPhatCat]

so i think some of these tuners are tryin to bulls**t us by saying youll lose 15% nominal no matter what the hp. then it gets some people cornfused, now because when they pump out 470hp at the wheels they add 15% back to that and think they got like 550hp when its closer to ~500hp~. so thats where im coming from. the only real way to measure hp is on a engine dyno, at the flywheel. then at that i woul only subtract what i know from my hp robbers on my car

Hehe And this drives home the point that RWHp is all that matters (in simplistic terms) when trying to understand the straight line performance of a vehicle. People pushing around imaginary flywheel HP numbers are just trying to impress the car illiterate masses. I understand why manufacturers list the flywheel Hp (bigger numbers are better), however it'd be nice if the standard were what they dyno.

 

[seths99cobra]

well i talked to the guy that built the motor at houston performance and he said that its very likely that that motor is makin over 600 at the flywheel if it was a high compression motor which i was told it was like 11 something. he said if i can get the guys name who ordered the motor originally he can pull the records and tell me what it made on the engine dyno. really to me it dont matter if its making that cause im getting a full built motor for a grand which i priced out that motor to be well over 4k in parts. its just a cheap build till i can afford to build a 5.4 swap with compound boost.

 

[billfisher]

dished pistons do not make 11:1 on a 4v. it takes flat tops. 4cc is stock.