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wanted 170 bhp

990 views 22 replies 12 participants last post by  ben k 
#1 ·
i've got a spare engine at the mo and i'm going to build it up to the following spec

skimmed head, by whatever is nessary to make sure it's dead flat
a hotter than sri 130 cam
twin weber 40's (already got them)
more flowing of the cylinder head (spare one)
rebore by 0.5 and new sri pistons of right size
total seal piston rings
sbd oil pump gears and relief valve
lightened flywheel
uprated clutch
balanced pistons,rods,crank
vernier cam wheel
head stud kit (instead of headbolts)
uprated head gasket
and all new seals as needed

will i get the 170 or near it?

it's an 8V engine i've got and i ain't changing it for a 16V
 
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#3 ·
a previous post on here said i could remove the big lump on the inlet side where the valve was to free up the flow and just to trim back the valve guide on the otherside so doing this and making sure as much of the dingle berries from the casting is removed to give good flow and mix charactistics. and before you say it yes i won't go past an 80 grit paper.

should be fun!!!

already stripped the engine down, just the crank and pistons to remove. what colour should i paint it? bearing in mind it's going into a black car at the end and i want it to stand out a bit? not black or silver as i'm getting loads of alloy bits for the bay eventually and don't want to much silver
 
#7 ·
I looked into head stud kits and was warned off. I'm sticking with std bolts, you don't need studs for reasonable NA tuning IMO.

As to power, yes 160-170BHP is a good aiming point. I work on the principle that my 2.0 8v is making 148BHP with a B+ head and std cam. Therefore, carbs allow another 10%, taking me to 165BHP ish, though a higher lift cam might be necessary to liberate that power.

BTW I love the 8v engines. So simple. And effective once derestricted.
 
#9 ·
With the stud kit you would still need to do the multi stage tightening,this is nothing to do with the bolts themseves is to you dont warp the head and get a good seal,if you can change a head its not exactly difficult to do the multi stage tightening,you may aswell,just think how gutted you'd be to find the head gasket leaks and the head was warped.
Whats wrong with the standardbolt setup anyway?
 
#13 ·
The advantage of studs is that you're not turning a big long bolt when you tighten the head. Now if you're running mega boost on a turbo engine this might be an advantage. But for a 170BHP NA engine, don't was the effort.

I was warned off it because the effort it getting it working right would outweigh any advantages. Bolts. Reasonably cheap and entirely predictable.
 
#14 ·
0ddball said:
instead of bolts you get a threaded rod, and nut set, re-useable, and none of this multi stage tightening sequence malarky just one torque setting.
Richard told me about these. He said they could hold the head down tighter as well as less stress was applied to it.

Sounds like a really good idea, expensive though.
 
#15 ·
Mmm sounds quite handy the Oddball, what kind of tensile threaded rod are you using?? That would also really help the risk of stripping the threads in the block, would it not??, i did strip the threads on ma last engine cos the motor factors gave me the wrong bolts!
 
#22 ·
update;


skimmed head, by whatever is nessary to make sure it's dead flat (done)
a hotter than sri 130 cam (kent ast15k cam kit)
twin weber 40's (already got them)
more flowing of the cylinder head (spare one) (well tweaked)
rebore by 0.5 and new sri pistons of right size (87 mm pistons now in)
total seal piston rings (didn't bother not worth the effort in the end)
sbd oil pump gears and relief valve (need a new casing first as i burst the old one)
lightened flywheel (how much can i take off the std one?
uprated clutch (on it's way next month)
balanced pistons,rods,crank (didn't bother as speaking to someone can't mind who said not to bother until i want to rev it past 7k)
vernier cam wheel
head stud kit (instead of headbolts) (went with bolts)
uprated head gasket (std is actually very good)
and all new seals as needed (damn the cost a bit as do the new bolts)
 
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