Lost on what to do for next upgrade

Tyler.SC1990

Registered User
So currently on my '90 SC I have a 76mm MAF, a 75mm throttle body, a Magnum powers Inlet plenum, a ported '94/'95 blower, a raised SC top, a 5% OD jackshaft pulley, and a beefy AOD transmission with a shift kit and better plates to top it off. Also, a K&N air filter to fit in my stock air intake box (if that counts).

I'm to the point where I'm not sure about doing something without having to do something else first so I was looking for some input/guidance. I know I'm pushing a lot of air in now and don't want to burn valves or blow a head gasket. I'm looking at 42pound injectors, a 255lph fuel pump, mid length headers with brand new exhaust all the way back, front mount intercooler, aluminum radiator, and a computer chip in there somewhere to make it all fall in sync.

I know that if I upgrade injector size that I am going to need a chip burnt to make it run as it should, I can't do the headers without doing my exhaust all the way back and that's a convienient time to put in a 93+ style gas tank to get a more direct flowing exhaust. It would also be easy to do the fuel pump at the same time. The fuel pump would be useless until I put the bigger injectors in as well I'm guessing. The supercharger is being overheated I'm guessing with the psi that it's pushing that a FMIC seems like it'd be a good idea but with as hot as it runs, choking out the air that the stock radiator gets seems like a bad idea, so it seems like an aluminum radiator would be good to do at the same time.

I know everyone seems to say the exhaust should be done first but with as much as it was going to set me back it was going to probably put all those other items on hold. Any advice on the order I should integrate all of these would be much appreciated.

Thanks everyone.
 
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So currently on my '90 SC I have a 76mm MAF, a 75mm throttle body, a Magnum powers Inlet plenum, a ported '94/'95 blower, a raised SC top, a 5% OD jackshaft pulley, and a beefy AOD transmission with a shift kit and better plates to top it off. Also, a K&N air filter to fit in my stock air intake box (if that counts).

I'm to the point where I'm not sure about doing something without having to do something else first so I was looking for some input/guidance. I know I'm pushing a lot of air in now and don't want to burn valves or blow a head gasket. I'm looking at 42pound injectors, a 255lph fuel pump, mid length headers with brand new exhaust all the way back, front mount intercooler, aluminum radiator, and a computer chip in there somewhere to make it all fall in sync.

I know that if I upgrade injector size that I am going to need a chip burnt to make it run as it should, I can't do the headers without doing my exhaust all the way back and that's a convienient time to put in a 93+ style gas tank to get a more direct flowing exhaust. It would also be easy to do the fuel pump at the same time. The fuel pump would be useless until I put the bigger injectors in as well I'm guessing. The supercharger is being overheated I'm guessing with the psi that it's pushing that a FMIC seems like it'd be a good idea but with as hot as it runs, choking out the air that the stock radiator gets seems like a bad idea, so it seems like an aluminum radiator would be good to do at the same time.

I know everyone seems to say the exhaust should be done first but with as much as it was going to set me back it was going to probably put all those other items on hold. Any advice on the order I should integrate all of these would be much appreciated.

Thanks everyone.
you might be able to just get away with porting the stock exhaust manifold instead of going with headers
 
So currently on my '90 SC I have a 76mm MAF, a 75mm throttle body, a Magnum powers Inlet plenum, a ported '94/'95 blower, a raised SC top, a 5% OD jackshaft pulley, and a beefy AOD transmission with a shift kit and better plates to top it off. Also, a K&N air filter to fit in my stock air intake box (if that counts).

I'm to the point where I'm not sure about doing something without having to do something else first so I was looking for some input/guidance. I know I'm pushing a lot of air in now and don't want to burn valves or blow a head gasket. I'm looking at 42pound injectors, a 255lph fuel pump, mid length headers with brand new exhaust all the way back, front mount intercooler, aluminum radiator, and a computer chip in there somewhere to make it all fall in sync.

I know that if I upgrade injector size that I am going to need a chip burnt to make it run as it should, I can't do the headers without doing my exhaust all the way back and that's a convienient time to put in a 93+ style gas tank to get a more direct flowing exhaust. It would also be easy to do the fuel pump at the same time. The fuel pump would be useless until I put the bigger injectors in as well I'm guessing. The supercharger is being overheated I'm guessing with the psi that it's pushing that a FMIC seems like it'd be a good idea but with as hot as it runs, choking out the air that the stock radiator gets seems like a bad idea, so it seems like an aluminum radiator would be good to do at the same time.

I know everyone seems to say the exhaust should be done first but with as much as it was going to set me back it was going to probably put all those other items on hold. Any advice on the order I should integrate all of these would be much appreciated.

Thanks everyone.

I would hold off on the exhaust and do the fuel system upgrades next. 42# injectors and a 255 hi pressure pump are good choices and as you mentioned you will need some tuning at that point. I suggest contacting David Dalke to burn you a chip to make the 42# injectors work.

David
 
I am in agreement with both comments above. I personally dont think its worth changing the gas tank, its one of those bro-sciences things. Its probably not worth buying the Kooks headers either (if you read enough on the forum you will understand why i say that). porting the manifolds and doing a mandrel systems exhaust would be appropriate for your mods.

you could do the fuel pump at any time (prior) as it shouldnt hurt anything Do the injectors and the chip at the same time, if you need to spread out the money. both jobs are decent sized jobs, so splitting those upgrades up would be smart IMO.

Not sure what "as hot as it runs" is about... however you could upgrade to 180 degree thermostat when you get a chip burned. you would need to do those at the same time because the fan settings should be changed to match the lower temp thermostat in the tune. I personally noticed not difference in my ECT because of having a FMIC, but i did not have problems before that either (ive had a griffin radiator since i started modding my sc.

If it were me i would do...

1. fuel pump upgrade
2. injectors, thermostat, chip upgrades
3. port manifolds
4. upgrade exhaust

use the money you saved not buying the headers to buy a better radiator if you want.
 
These guys are right. Headers are a complete waste of money until at least after you have done ported heads and cam, if even then.

Get a complete dual exhaust kit from Tru Benz for the late model gas tank. At your power level I recommend that you get the dual 2.25" kit. It's not that expensive and it fits stock manifolds.

Upgrade the fuel pump and injectors at the same time. Yes, you'll need a chip for it to work correctly.

The FMIC is not that bad for increasing engine temps if you get/make a kit that fits in front of the AC core instead of between it and the radiator. Then increase your OD from 5% to 10% using a 5% blower pulley. An aluminum radiator in and of itself is not an improvement. It's only an improvement when the one you get has a lot more capacity than stock. Keep that in mind. You'll also need to make sure that you get plenty of airflow no matter which one you get. Some people use universal aftermarket radiators, but sometimes making the stock fan work with them can be a challenge. Aftermarket fans do NOT move as much air as the stock two speed fan, so keep that in mind. A Griffin is expensive, but it's the best and easiest to make fit.

The stock airbox is also a restriction, so go ahead and figure in an aftermarket 3" or 3.5" intake tube and cold air divider with a cone style filter.

The only reasons you'll run any risk of blowing a headgasket is due to an incorrect tune, lack of fuel (you are already WAYYyyyy out of injectors), failing cooling system, and of course the inevitable fact that aluminum heads and iron block engines + forced induction always blow headgaskets no matter the manufacturer. You can take care of the first 3 factors, but the last one is just a fact that you'll have to reconcile in your mind. There is nothing you can do that will prevent eventual headgasket failure.
 
wait WAIT, you have all those mods and stock exhaust ? from what ive been told your going to be at high risk of head gasket failure.
I would for shur go with some dual 2.5in with catless or atleast high flow cats for ur next mod/upgrade. id also take that time to upgrade ur gastank for the better routing and also upgrade ur fuel pump so when the time comes,which is soon ulle have it done. and imo borla mufflers sound the best on v6's..
I wont even do anything to raise my boost above 12psi until I have high flow exhaust or new headgaskets..
 
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Thanks everyone for their input and I have some direction heading forward. In regards to my "running hot" comment I just ment that it gets to the M in "NORM" on the temp gauge before the fan kicks on so when I'm in stop and go traffic I sit close to M. The entire engine was rebuilt with new gaskets, Harmonic balancer, etc 6,000 miles and there is almost nothing mechanically that hasn't been replaced on it since I bought the car 10,000 miles ago minus the rear end. I was planning on putting in a Griffin radiator as I have read good remarks and it looks as though it's about double the size of the stock plastic one.

Thanks again and I have some direction to go now. I'll get ahold of Dave here soon.

Tyler
 
In regards to my "running hot" comment I just ment that it gets to the M in "NORM" on the temp gauge before the fan kicks on so when I'm in stop and go traffic I sit close to M.[/QUOTE said:
At the factory settings the puller fan kicks on at 220 degrees which is right at the M assuming a good temp gauge sending unit. Yes that's still pretty hot but that's the way these car's were setup.
 
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