500whp is a high goal for the 68HTA. It is possible, as I have heard of it being done. It is just not likely to see those numbers. If you do hit those numbers you are going to be milking the turbo. 500whp is also too much HP for autocross IMO. If you are actually making 400hp on that 68HTA with stock cams that is pretty damn respectable and unheard of in my book.

With that being said, 272's will be good for either set up. You don't have to upgrade the valvetrain either if you don't really want to.

A few things. Which version of the 68hta?

Joe Bucci made just shy of 500whp on the v2 on his 2.3 and is running solid 10s. on e-85 it isn't horribly difficult if you plan your build.

I'd say HKS/DKS 272s, FP2 cams (Comp cams 101102 grind. same thing) I'd stay away from kelford if you want to maintain good spool. or possibly GSC sc2?

I'm on the v1 68hta at 30psi and flowing 51/lbs a min.. which in a perfect world would mean I'm just shy of 510whp on my car (I'm not.. but wouldn't that be nice?) but the flow numbers are real. It's not as difficult as everyone makes it out to be to make solid.. muscle car heart breaking power in these cars, most guys just give up and throw a bigger turbo on before pushing the limits of the td05 turbos.

I wouldn't be surprised if you were very near your goal on a 2.0 and e-85 on a v2 68hta with a good tune assuming you have all the proper supporting mods.. oh and cams Electronic boost control would be a must to maintain boost pressure to redline. on a dynojet of course. mustang dyno would make you cry.

Thanks for the replies! just ordered some HKS 272s. Also I have the v2 68hta and I am playing around with a super short route water to air intercooler setup so I can run some 10.5:1 pistons. Juan Mascorro did 501hp/444tq on high compression and e85 on a drag setup.

605jdm said:

Thanks for the replies! just ordered some HKS 272s. Also I have the v2 68hta and I am playing around with a super short route water to air intercooler setup so I can run some 10.5:1 pistons. Juan Mascorro did 501hp/444tq on high compression and e85 on a drag setup.

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Keep in mind that Juan had virtually every mod known to man and top DSM shop dyno tuning the car.

I believe.. @Kapok6 was running a high comp e-85 motor and can give you some better insight.. I know his opinions but I'll let him speak for himself.

19gsx91 said:

I believe.. @Kapok6 was running a high comp e-85 motor and can give you some better insight.. I know his opinions but I'll let him speak for himself.

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Well you've already spoken for the great Joe Bucci....

From Juan Mascaro:

Boosting performance stage 3 6 bolt short block high compression ratio. Boosting performance stage 3 7 bolt head rebuild. Running on E85 with a 450 and a 255 fuel pumps with 1150 fic injectors. For exhaust manifold evo3 intake manifold, stock 7 bolt throttle body. Car was on ecmlink. ETS short route intercooler kit 24x12x3.5. Kelford 272 cams

I mentioned his horsepower. not his personal takeaway on the turbo

My opinion...fk high comp 4g63. Also, not all 272's are created equal. I've used hks 272 and fp2's/comp, as well as GSC S2. Hks/comp will give you more low end/sooner boost than something like the kelford/GSC S2. Based on what you said you wanted above, I'd personally go with the hks/comp/fp.