performance combo?

[fullahotair]

Hello folks, i have bone stock (save a K&N and new 2.25 SS up pipe) 85 GN with 90,000 miles on it. I have been reading just about everything i can find on these cars and have come up with the following mods, and i wanted to sound these off you guys for your experience thoughts. I want at least a low 13/high 12 sec car, and i just don't want to spend money haphazardly, but i am willing to spend what it takes--the first time. This is what i have come up with, in order of which to complete them...

1. walbro 307 fuel pump, adj fp regulater, fp guage, hotwire kit.


2. 86/87 ecm conversion with a thrasher chip, and turbo link. My intent here is tune the car to its peak prior to the mods listed below. Eventually, after the other mods, i would like to progress to a translator + with extender chip and ls1 MAF, once i get a solid running car. Or should i just go directly to the translator. I fear that the tuning capacity of the trans + could be a blessing and a curse?? Your thoughts on this would be greatly appreciated

3. Postons headers, crossover, and downpipe. Should I find a 3" pipe or will a 2.5" suffice??? Are the benefits of the 3" worth it?

4. New valve springs, timing chain, and cold air kit.

5. Eventually porting/polishing the heads and intake

Do you think these mods will push me into the low 13's and high 12's? How about an aftermarket cam?! I don't want to intercool, becuase that would be too easy. Really any advice/input would be greatly appreciated. Thanks in advance.

 

[fullahotair]

oh one more thing... i want to get a bigger turbo. any thoughts on which one. Is it the TA33 that is a direct bolt in? Thanks again.

 

[WFO]

you've done your homework good job,gold star.

i'd say put the ta-33 in as # 2.5.

i'd definitely go with an aftermarket cam(nothing huge 204-214)when you do the springs/timing chain.

the 2.5"dp has gone 117mph on chris wilson's car,so it has performance potential.rumor has it that mease is making 3" dp's for hotairs now,so if you can get one,do it.it'll will go nicely with the poston's headers.

as far as the maf goes,i'd hold off until either your stocker craps out or you're ready for the extender chip.you'll have the hang of tuning these things by then,and the trans+/extender will give you complete control.

once you get some ported heads/intake/cam you'll definitely be able to run solid 12's(with race gas/slicks).you'll probably want to look into alky/propane to run with your pump gas.

what exhaust are you running?

later,sean

 

[fullahotair]

Thanks for the reply...

Right now i have a 2.25 custom exhuast system right now. Do you have a price for the 3" dp?

The thrasher chip has been getting mixed reviews in regards to running an intercooler or not. But i see some people just turn down the fuel pressure to 38 to 39 and seem to be ok. Is there another chip that people prefer over this one!? Where can i contact someone about getting a thrasher chip should i choose too...

Thanks again...

 

[WFO]

i don't think the 3" dp's are officially for sale yet.

i think you should be fine with the thrasher if you turn the fp down a little.that's where that scan tool comes in.

you can get the chips from scott:

Scott231@gnttype.org

Scott231@Juno.com

 

[mycarsucks]

personally I would get a walbro 340 instead. The cost isn't that much more, it has much better potential, and changing an intank pump once is enough for me. I would feel foolish if I had to upgrade later.

 

[fullahotair]

Thanks for all the input guys, i'll let everyone know the progress and the gains i get from this.

 

[cool 84]

I know you don't want to go intercooled and I didn't at first either. But the benefits (20% power increase comes to mind) are too great to overlook. Not only will you make more power but you can get away with "smaller" parts. Like a smaller cam and smaller turbo and still run faster times. My car would also pull to ~5,000rpm with the IC vs 4,500 without.

You should try an IC,TA33, 2.5 or bigger DP, Posten's headers, thrasher, and the fuel mods you mentioned before you go into the motor. I have a feeling you won't be feeling the need to open the motor after that .

 

[cool 84]

Here's something to think about that I just remembered. My friend has a GN1 headed, ported intake, 210-205cam, TA62, 2.5" DP, and fuel mods. He had to get it smogged and pulled every mod off except the cam, turbo, and DP. I'm not sure how much that cam was helping with bone stock heads and intake. We took it to the track one night and on only 19psi it trapped 106mph. That's basically two power producing mods so I think it goes without saying how important the turbo and DP are on a hotair. That's street trim for that car and if it had the correct convertor it could've gone mid 12s.

 

[fullahotair]

What intercooler are you running in your car? Spearco? I hear a lot of people using this or the Ford intercooler.

Do you have any pictures of your setup? i would be interested in seeing them.

Is the TA33 pretty much the concensus for the turbo to upgrade to? John Craig carries these for about 800 bucks if i am not mistaken.

At what point does the 307 pump wheeze out compared to the 340?

 

[fullahotair]

What torque convertors are everyone upgrading too, its one thing i have yet to look into?

 

[mycarsucks]

I'm not sure if there is any reason to go with a 33 if you are going intercooled. I thought, but could be wrong that the only benefit to that turbo was that it would work in the stock location. You could probably get cheaper or equal cost turbo that would be a better performer if you were going with an IC. You dont have many options for an IC right now. If you want a kit all you have is the spearco. Some have used the Ford IC because of its low price, but it is definately not a bolt in item, takes a lot of fabrication, and quite a bit of your time.

I'll try to get some pictures of my setup, but it isn't pretty. I had to get it together fast so I could drive it to a shop and get the bearings replaced. So, one of my tubes is a rusty style and I have a riceboy airfilter because thats all they had at my auto parts store.