97SS0594

why not build an off displacement motor like a 357, or a 381? but ive had decent luck when my 355 was in my Z28, just fed it a butt ton of spray and let her eat but either way your heads are going to be your bottle neck. also ive learned boosted is where its at na is fun but if you want have a fast car that is tolerable on the street you need a power adder, NA is just pointless these days.

IrocSS85

as for the 6.0" rod question, I can vouch that neither are true. my car was extremely driveable. it would start in any weather with the first twist of the key, got 15-16mpg mixed driving and I always let the car warm up for a few min.s before I drove off. NO quirks either while driving down the road. my car did leak oil due to my gutting the valve covers. it would seep out the center bolt holes. so I cant tell you how much oil it burned. but I can say after 4 years of driving, 8K miles no oil residue on the spark plugs and the pistons look very good and pretty clean. usual carbon but thats it. I pulled the heads cause I had cheap single valve springs and one broke last fall so i bent a valve. now Im returning the car to bolt on status for sale. the 6.0" rods are supposed to broaden the power band by raising the torque/HP down low w/o affecting the upper parts of the power band.

OPies57

awesome definitly getting the 6.0s then gonna be awesome feed it lots of nitrous

on the other note
you should be ashamed of yourself i still am iffy about the zr1

OPies57

alright so i had my 383 built fully forged with 6.0 h beams and forged pistons with hellfire rings gapped for nitrous. now im wondering if i need to plum my fuel rails and if the racetronix 42lbd injectors will work with the stock rail or if i need a resistor pack or something. i dont know if stock ones are high or low impedence. im getting my heads and manfold ported and having a custom cam ground for the beast. anybody have any horsepower predictions?

IrocSS85

not till the flow charts and cam specs are given. I'll wait patiently though.

OPies57

what are people putting down with 383s and stock ported heads normally?

IrocSS85

well you dont typically get a whole lot more HP, I think due to the intake being the same. and the heads are typically the same. but you get a lower rpm peak power, and a TON more low end torque as well as a WIDER power band. not really peaky like a 350 with all the same stuff on it.

NightTrain66

383 will make another 15-20 ft lbs of TQ but not any more peak HP. It will make a lil more HP under the curve due to the added compression (if you have the right pistons) and have more HP/TQ at 2000, 2500, 3000, 3500, 4000, 4500, 5000 and 5500 RPM.

A 383 with ported LT1 heads will make peak power at around 5900-6200 RPM (depending on how nice the heads are and how large the cam is) but it will always be about 300 RPM lower than a 355 with the same heads/cam. Same haeds/cam in a 355 would amke the same HP but at 6500 RPM.

Even though the 383 makes peak HP at 6200 RPM, you can still have the HP #'s stay there until 6500 or even 6700-6800 RPM if the cam is larger enough.

383 will usually make a street car faster, especially if theer is not alot of gear/stall. If you have lots of gear/stall and a lighht car, the 355 (if shifted at 6800 RPM or higher) can be even faster since the 383 will be a lil RPM limited. Not everybody wants to spoin there 355 6800 RPM (or higher) and even if so, a cam made for this will not have much low end power so street manors will not be so greata nd you needs lots of gear/stall to make it work.

lots of answers to the question (355 vs 383) but a street car with 3.73 gears and 3600 stall (or less gear/stall) will be better off with the 383 and have more street manors.

The people that use a 383 with stock heads are killing themselves and the $$$ spent towards the 383 should go towards a nice set of heads and corrct cam for there set up and put back on a 355. The car will be faster and more fun to drive than a 383 with a catalog cam and stock heads.

Lloyd

ABA383

Im an A4 with a 383 with LPE/Eric Bradby ported stockers with 2.00/1.56s...the cam is a weenie 226/234 Joe Overton/Erson cam...The car made a whopping 375 rwhp on a calibrated Mustang dyno...However, the times mph in my sig would suggest otherwise...The nice thing about the 383 is the lower rpms needed to have fun...I think one of the reasons why my bottom end has been together for 13 years is that everything is done by 6300 rpm...That and good parts selection...But its nice not to have to run a huge converter and big gears...

--Alan

OPies57

i figured id go with the 383 i could always put heads on it at a later date

OPies57

other then getting bigger injectors and fuel pump do i need to do anything else to my fuel system? adjustable fuel pressure regulator to up the fuel pressure?

NightTrain66

Walbro 255 pump, bigger injectors and good computer tuning will be all you need, Stock MAF and stock fuel pressure regulator will be best.

Lloyd

wrd1972

Bunk. My 355 has 6" Scat forged rods and drivability is outstanding and power is awesome.

<Puck>

I still plan on reusing my cam that did 11's stock cubes again in my 383. It is eerily similar to yours and was very nice in the 350, and I am anxious to see how it performs in a 383. I get a LOT of people saying its way too small for a 383, and I am tempted to go a lot bigger often, but the heads are not that great anyway so I am trying to fight the temptation. Not to mention then I would need more stall and gearing to wake a big cam up.

I love the higher lift/lower duration cams on a nice high compression NA LT1. Driveable combo with power on tap all the time, no bottles or boost tunes to worry about .

If you can afford to do it right, def go 383!

OPies57

sweet and will 42lb injectors be big enough?