Advice for 355

[Not_An_Abba_Fan]

I agree with the above, you would be battling to get 300hp let alone 400. 400rwhp is expensive. I built a 355 not that long ago but kept the standard heads and banana intake. Never got it dyno'd but just by feel, I reckon it was under 300.

The standard computer can handle it, a few people are really good at tuning them. The one I built already had a Haltech. I didn't mind it, but not many people can tune them.

Hydraulic cams aren't that bad. Flat tappet is more of a worry, I munched 2 cams because of issues starting it. Go roller. I read an article on a guy that built a 5.0L in a Mustang and had valve float at anything above 5000rpm. Worked out that the solid lifters were not letting the valves close properly, changed to hydraulic lifters and the damping let it rev cleanly to 8000rpm. Different engine, but interesting to read.

 

[Deuce]

I agree with mr j-man. Get hpe to build it. The owner is very talented and a really good guy. He even helped me build some nice heads for my harley with free advice over the net. What a legend! !

 

[drew852]

im not wasting my money to send my motor away when I got a perfectly knowledgeable and well know engine builder here, no offence intended I just wanted opinions and options on the motor and setup is all, from I can gather the h304 is not a good option? should I go roller? cheers boys

 

[Vs hsv manta]

No offence taken at all

It was only a suggestion as with Pavtek you know what your getting before you start

X amount of dollars, no chance of blowing out in cost and gets a 525 hp engine end of story

And it cost me $350 dollars to send my engine from nth qld to Melbourne and back so was hardly a waist

But it was only a suggestion and first place that come to mind, plenty of good builders around the place to choose from

But as for your Combo honestly your a long way of 400rwhp, your talking about the difference from easy to get 330rwhp to 400rwhp step that requires a mild engine to become wild and big dollars start to come Into it

End of the day what's it for ?? Is it daily street or weekend street or weekend street with sometimes strip use ?? Clearly it's not a full time strip engine

This and $$$ is the major contributing factors that will determine what you end up with, unfortunately N/A street use holden stroker engines on 98 are usually fearly average in today's standards

Very very hard to get a 11.9 second N/A holden engine on 98 to be extremely street friendly as well in a second gen commodore

If you want 400rwhp it will be a $15K motor that will suck fuel like crazy and be a cranky engine

Personally I would go a 383 and grout fill it to the welsh plugs, slap a girdle and ASR sump as there great items for bottom end, work the heads like crazy run the manifold or similar and similar or same cfm throttle you listed and depending on weather you able to adjust your own rockers and wether it's daily or weekend use or not would determine weather I would go a hydrolic or solid cam, either would be a roller

Depending on weather it's daily or weekend use and if e85 is available around your area would determin comp

If you get axcess to e85 and it's weekend use I would go up towards 13:0.1 comp and 400rwhp will be in your pocket possibly with a nice hydrolic cam and still user friendly (possibly)

If not back to mid 11 comp and hydrolic cam will be 330ish rwhp
To gain 400rwhp on 98 would need a big solid cam up In The 250s range with 0.580+ lift high rise manifold and big pipes and will probley rip your T5 or getrag (if that's the manual you have) into multiple peices fearly quickly

I think your heads are the main let down at the moment and that's the only reason your cam choose isn't good at the moment, do head work and it's a good cam but not 400rwhp worthy on 98

One things for certain though if I built a N/A holden stroker it would be 383 and grout filled with a girdle as a base platform to start from

 

[drew852]

I see your point, its gonna be a daily but I want a tough daily, im doin my apprenticeship atm and want something to be proud of, car looks mint as and im selling my skyline to pay the machine shop, I kinda wanna be at around 250-300 rwkw. bottom line I wanna race my bros ve r8 and shut him up lol, but really I want a nice sounding pretty tough streeter, don't really mind if its a bit of a pig to drive. you reckon I should go with the h304 and port the standard heads? upgrade to a dual 2.5 exh over the 3inch, pretty much stuck with the t5 atm but im planning a 6speed down the track

 

[Vs hsv manta]

Yes port the standard heads unless you are planing on 550plus hp the. The alloys are a $2000 jump over the cost of porting cast heads to support the extra power

What your really better of doin is a LS swap

Then you have a chance of shutting him up

A ve r8 will get into the 12s with a exhaust tunes stally or clutch and diff gears and into the 11s with a head and cam package

You will be flat out getting into the 11s full stop

Conversion kits are readily available and straight forward, but a wright off

Chuck a ls2 or 3 (if you can get hands on a wreck )in it then you can shut him up easily

 

[Vs hsv manta]

Have a look at cars on here like deuce, not a abba fan, ssute and countless others

A N/A 355 requires a lot of money to go fast and then it's a very very expensive toy to keep running as well, you will use 14 litres just cruising and 25 if you give it a hard time per 100km

I can shut LS3 of all sorts up but I have $25+k between the radiator and flywheel and then I have a lot of money after the flywheel as well

To give you a idea iv used 25 litres in a solid camed 355 with 7psi in a 50-65 km drive, that's doin 10km warm up 25 km flat out after every corner and cruising 15km return trip, stoped at the servo on way home and it took 25 litres that's nearly $40 for a half hour fun drive

Even me earning good money I wouldn't even come close to been able to afford to drive a cranky fuel guzzler daily

Look at a LS option and if you want to go fast do it once you have a second car to do your daily driving in

 

[mr j-man]

heres an example :blah blah: ....well my engine basically!

I built my own 355
It cost me approx. 12k + new 4500 8" stall converter and a new set off 3.55 diff gears
And all I started with was a bare VS 5.0l block....nothing else.

I had some extensive port work on the heads by HPE which flow a maximum of 282cfm on the intake valve which equates 535hp at a RPM Range of 4,995 to 6,495
for my engine size of 355 CID.

Made 385rwhp and run a best ET of 11.7 @ 118mph due to the 3.55:1 gears in the diff.....its an 11.0 sec motor.. it just needs the 4.11's

I did have a similar cam to the crane 280 which ran the above figures.....but Ive now fitted the crane 288 solid flat tappet cam which will see a better HP number and a higher RPM.
This should get the best out of the heads and intake manifold.

I drive it as much as possible on the street and have embarresd plenty of LS's and XRT's much to their disgust ....yes it is thirsty but I don't care

The difference between a hyd flat tappet and the solid flat tappet is that solid will RPM hell of a lot better and is more of a mongrel cam compared to a Hyd.......and don't believe all that talk about solid cams needing more maintenance with setting valve lash all the time.....its a wives tale.

If you want to go a hyd roller or solid roller cam....expect to pay an extra 2k on top.

But by all means if you have a good engine builder take his advice not ours cause if it turns out to be a turd of an engine you can go and blame him to his face :boxing:

 

[drew852]

Awesome guys I still appreciate your comments, I'm gonna go the h304 cam route and port the heads, what ever hp I get is what it is, I've poured far to much money into this motor alone so I'm gonna run what I got, if I get hp hungry I'll go the charger or turbo route later on, I mean it won't be too far off prep for that when it's running. Once again cheers

 

[Not_An_Abba_Fan]

I used the H304 cam, biggest hydraulic Crane cam you can get. Nice lumpy idle and good torque curve.